xref: /xnu-12377.1.9/bsd/kern/kern_exec.c (revision f6217f891ac0bb64f3d375211650a4c1ff8ca1ea)
1 /*
2  * Copyright (c) 2000-2020 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
29 /*
30  * Mach Operating System
31  * Copyright (c) 1987 Carnegie-Mellon University
32  * All rights reserved.  The CMU software License Agreement specifies
33  * the terms and conditions for use and redistribution.
34  */
35 
36 /*-
37  * Copyright (c) 1982, 1986, 1991, 1993
38  *	The Regents of the University of California.  All rights reserved.
39  * (c) UNIX System Laboratories, Inc.
40  * All or some portions of this file are derived from material licensed
41  * to the University of California by American Telephone and Telegraph
42  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
43  * the permission of UNIX System Laboratories, Inc.
44  *
45  * Redistribution and use in source and binary forms, with or without
46  * modification, are permitted provided that the following conditions
47  * are met:
48  * 1. Redistributions of source code must retain the above copyright
49  *    notice, this list of conditions and the following disclaimer.
50  * 2. Redistributions in binary form must reproduce the above copyright
51  *    notice, this list of conditions and the following disclaimer in the
52  *    documentation and/or other materials provided with the distribution.
53  * 3. All advertising materials mentioning features or use of this software
54  *    must display the following acknowledgement:
55  *	This product includes software developed by the University of
56  *	California, Berkeley and its contributors.
57  * 4. Neither the name of the University nor the names of its contributors
58  *    may be used to endorse or promote products derived from this software
59  *    without specific prior written permission.
60  *
61  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
62  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
63  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
64  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
65  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
66  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
67  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
68  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
69  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
70  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
71  * SUCH DAMAGE.
72  *
73  *	from: @(#)kern_exec.c	8.1 (Berkeley) 6/10/93
74  */
75 /*
76  * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
77  * support for mandatory and extensible security protections.  This notice
78  * is included in support of clause 2.2 (b) of the Apple Public License,
79  * Version 2.0.
80  */
81 #include <machine/reg.h>
82 #include <machine/cpu_capabilities.h>
83 
84 #include <sys/cdefs.h>
85 #include <sys/param.h>
86 #include <sys/systm.h>
87 #include <sys/filedesc.h>
88 #include <sys/kernel.h>
89 #include <sys/proc_internal.h>
90 #include <sys/kauth.h>
91 #include <sys/user.h>
92 #include <sys/socketvar.h>
93 #include <sys/malloc.h>
94 #include <sys/namei.h>
95 #include <sys/mount_internal.h>
96 #include <sys/vnode_internal.h>
97 #include <sys/file_internal.h>
98 #include <sys/stat.h>
99 #include <sys/uio_internal.h>
100 #include <sys/acct.h>
101 #include <sys/exec.h>
102 #include <sys/kdebug.h>
103 #include <sys/signal.h>
104 #include <sys/aio_kern.h>
105 #include <sys/lockdown_mode.h>
106 #include <sys/sysproto.h>
107 #include <sys/sysctl.h>
108 #include <sys/persona.h>
109 #include <sys/reason.h>
110 #if SYSV_SHM
111 #include <sys/shm_internal.h>           /* shmexec() */
112 #endif
113 #include <sys/ubc_internal.h>           /* ubc_map() */
114 #include <sys/spawn.h>
115 #include <sys/spawn_internal.h>
116 #include <sys/process_policy.h>
117 #include <sys/codesign.h>
118 #include <sys/random.h>
119 #include <crypto/sha1.h>
120 
121 #include <libkern/libkern.h>
122 #include <libkern/amfi/amfi.h>
123 #include <libkern/crypto/sha2.h>
124 #include <security/audit/audit.h>
125 
126 #include <ipc/ipc_types.h>
127 
128 #include <mach/mach_param.h>
129 #include <mach/mach_types.h>
130 #include <mach/port.h>
131 #include <mach/task.h>
132 #include <mach/task_access.h>
133 #include <mach/thread_act.h>
134 #include <mach/vm_map.h>
135 #include <mach/mach_vm.h>
136 #include <mach/vm_param.h>
137 #include <mach_debug/mach_debug_types.h>
138 
139 #include <kern/sched_prim.h> /* thread_wakeup() */
140 #include <kern/affinity.h>
141 #include <kern/assert.h>
142 #include <kern/ipc_kobject.h>
143 #include <kern/task.h>
144 #include <kern/thread.h>
145 #include <kern/coalition.h>
146 #include <kern/policy_internal.h>
147 #include <kern/kalloc.h>
148 #include <kern/zalloc.h> /* zone_userspace_reboot_checks() */
149 
150 #include <os/log.h>
151 
152 #if CONFIG_MACF
153 #include <security/mac_framework.h>
154 #include <security/mac_mach_internal.h>
155 #endif
156 
157 #if CONFIG_AUDIT
158 #include <bsm/audit_kevents.h>
159 #endif
160 
161 #if CONFIG_ARCADE
162 #include <kern/arcade.h>
163 #endif
164 
165 #include <vm/vm_map_xnu.h>
166 #include <vm/vm_kern_xnu.h>
167 #include <vm/vm_protos.h>
168 #include <vm/vm_fault.h>
169 #include <vm/vm_pageout_xnu.h>
170 #include <vm/pmap.h>
171 #include <vm/vm_reclaim_xnu.h>
172 
173 #include <kdp/kdp_dyld.h>
174 
175 #include <machine/machine_routines.h>
176 #include <machine/pal_routines.h>
177 
178 #include <pexpert/pexpert.h>
179 #include <pexpert/device_tree.h>
180 
181 #if CONFIG_MEMORYSTATUS
182 #include <sys/kern_memorystatus.h>
183 #endif
184 
185 #include <IOKit/IOBSD.h>
186 #include <IOKit/IOKitKeys.h> /* kIODriverKitEntitlementKey */
187 
188 #include "kern_exec_internal.h"
189 
190 #include <CodeSignature/Entitlements.h>
191 
192 #include <mach/exclaves.h>
193 
194 
195 extern boolean_t vm_darkwake_mode;
196 
197 /* enable crash reports on various exec failures */
198 static TUNABLE(bool, bootarg_execfailurereports, "execfailurecrashes", false);
199 
200 #if XNU_TARGET_OS_OSX
201 #if __has_feature(ptrauth_calls)
202 static TUNABLE(bool, bootarg_arm64e_preview_abi, "-arm64e_preview_abi", false);
203 #endif /* __has_feature(ptrauth_calls) */
204 
205 #if DEBUG || DEVELOPMENT
206 static TUNABLE(bool, unentitled_ios_sim_launch, "unentitled_ios_sim_launch", false);
207 #endif /* DEBUG || DEVELOPMENT */
208 #endif /* XNU_TARGET_OS_OSX */
209 
210 #if DEVELOPMENT || DEBUG
211 os_log_t exec_log_handle = NULL;
212 #define EXEC_LOG(fmt, ...)      \
213 do {    \
214 	if (exec_log_handle) {      \
215 	        os_log_with_type(exec_log_handle, OS_LOG_TYPE_INFO, "exec - %s:%d " fmt, __FUNCTION__, __LINE__, ##__VA_ARGS__);    \
216 	}   \
217 } while (0)
218 #else /* DEVELOPMENT || DEBUG */
219 #define EXEC_LOG(fmt, ...)  do { } while (0)
220 #endif /* DEVELOPMENT || DEBUG */
221 
222 #if CONFIG_DTRACE
223 /* Do not include dtrace.h, it redefines kmem_[alloc/free] */
224 extern void dtrace_proc_exec(proc_t);
225 extern void (*dtrace_proc_waitfor_exec_ptr)(proc_t);
226 
227 /*
228  * Since dtrace_proc_waitfor_exec_ptr can be added/removed in dtrace_subr.c,
229  * we will store its value before actually calling it.
230  */
231 static void (*dtrace_proc_waitfor_hook)(proc_t) = NULL;
232 
233 #include <sys/dtrace_ptss.h>
234 #endif
235 
236 #if __has_feature(ptrauth_calls)
237 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_per_team_id,
238     "vm_shared_region_per_team_id", 1);
239 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_by_entitlement,
240     "vm_shared_region_by_entitlement", 1);
241 
242 /* Upon userland request, reslide the shared cache. */
243 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_aslr,
244     "vm_shared_region_reslide_aslr",
245 #if CONFIG_RESLIDE_SHARED_CACHE
246     1
247 #else
248     0
249 #endif /* CONFIG_RESLIDE_SHARED_CACHE */
250     );
251 
252 /*
253  * Flag to control what processes should get shared cache randomize resliding
254  * after a fault in the shared cache region:
255  *
256  * 0 - all processes get a new randomized slide
257  * 1 - only platform processes get a new randomized slide
258  */
259 TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_restrict,
260     "vm_shared_region_reslide_restrict", 1);
261 
262 #if DEVELOPMENT || DEBUG
263 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_per_team_id,
264     CTLFLAG_RW, &vm_shared_region_per_team_id, 0, "");
265 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_by_entitlement,
266     CTLFLAG_RW, &vm_shared_region_by_entitlement, 0, "");
267 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_restrict,
268     CTLFLAG_RW, &vm_shared_region_reslide_restrict, 0, "");
269 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_aslr,
270     CTLFLAG_RW, &vm_shared_region_reslide_aslr, 0, "");
271 #endif
272 #endif /* __has_feature(ptrauth_calls) */
273 
274 #if DEVELOPMENT || DEBUG
275 static TUNABLE(bool, enable_dext_coredumps_on_panic, "dext_panic_coredump", true);
276 #else
277 static TUNABLE(bool, enable_dext_coredumps_on_panic, "dext_panic_coredump", false);
278 #endif
279 extern kern_return_t kern_register_userspace_coredump(task_t task, const char * name);
280 #define USERSPACE_COREDUMP_PANIC_ENTITLEMENT "com.apple.private.enable-coredump-on-panic"
281 #define USERSPACE_COREDUMP_PANIC_SEED_ENTITLEMENT \
282 	"com.apple.private.enable-coredump-on-panic-seed-privacy-approved"
283 
284 extern void proc_apply_task_networkbg_internal(proc_t, thread_t);
285 extern void task_set_did_exec_flag(task_t task);
286 extern void task_clear_exec_copy_flag(task_t task);
287 proc_t proc_exec_switch_task(proc_t old_proc, proc_t new_proc, task_t old_task,
288     task_t new_task, struct image_params *imgp, void **inherit);
289 boolean_t task_is_active(task_t);
290 boolean_t thread_is_active(thread_t thread);
291 void thread_copy_resource_info(thread_t dst_thread, thread_t src_thread);
292 void *ipc_importance_exec_switch_task(task_t old_task, task_t new_task);
293 extern void ipc_importance_release(void *elem);
294 extern boolean_t task_has_watchports(task_t task);
295 extern void task_set_no_smt(task_t task);
296 #if defined(HAS_APPLE_PAC)
297 char *task_get_vm_shared_region_id_and_jop_pid(task_t task, uint64_t *jop_pid);
298 #endif
299 task_t convert_port_to_task(ipc_port_t port);
300 
301 #if CONFIG_EXCLAVES
302 int task_add_conclave(task_t task, void *vnode, int64_t off, const char *task_conclave_id);
303 kern_return_t task_inherit_conclave(task_t old_task, task_t new_task, void *vnode, int64_t off);
304 #endif /* CONFIG_EXCLAVES */
305 
306 /*
307  * Mach things for which prototypes are unavailable from Mach headers
308  */
309 extern void ipc_task_enable(task_t task);
310 extern void ipc_task_reset(task_t task);
311 extern void ipc_thread_reset(thread_t thread);
312 
313 #if DEVELOPMENT || DEBUG
314 void task_importance_update_owner_info(task_t);
315 #endif
316 
317 extern struct savearea *get_user_regs(thread_t);
318 
319 __attribute__((noinline)) int __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid);
320 
321 #include <kern/thread.h>
322 #include <kern/task.h>
323 #include <kern/ast.h>
324 #include <kern/mach_loader.h>
325 #include <kern/mach_fat.h>
326 #include <mach-o/fat.h>
327 #include <mach-o/loader.h>
328 #include <machine/vmparam.h>
329 #include <sys/imgact.h>
330 
331 #include <sys/sdt.h>
332 
333 
334 /*
335  * EAI_ITERLIMIT	The maximum number of times to iterate an image
336  *			activator in exec_activate_image() before treating
337  *			it as malformed/corrupt.
338  */
339 #define EAI_ITERLIMIT           3
340 
341 /*
342  * For #! interpreter parsing
343  */
344 #define IS_WHITESPACE(ch) ((ch == ' ') || (ch == '\t'))
345 #define IS_EOL(ch) ((ch == '#') || (ch == '\n'))
346 
347 extern vm_map_t bsd_pageable_map;
348 extern const struct fileops vnops;
349 extern int nextpidversion;
350 
351 
352 #define USER_ADDR_ALIGN(addr, val) \
353 	( ( (user_addr_t)(addr) + (val) - 1) \
354 	        & ~((val) - 1) )
355 
356 /*
357  * For subsystem root support
358  */
359 #define SPAWN_SUBSYSTEM_ROOT_ENTITLEMENT "com.apple.private.spawn-subsystem-root"
360 
361 /*
362  * Allow setting p_crash_behavior to trigger panic on crash
363  */
364 #define SPAWN_SET_PANIC_CRASH_BEHAVIOR "com.apple.private.spawn-panic-crash-behavior"
365 
366 /* Platform Code Exec Logging */
367 static int platform_exec_logging = 0;
368 
369 SYSCTL_DECL(_security_mac);
370 
371 SYSCTL_INT(_security_mac, OID_AUTO, platform_exec_logging, CTLFLAG_RW, &platform_exec_logging, 0,
372     "log cdhashes for all platform binary executions");
373 
374 static os_log_t peLog = OS_LOG_DEFAULT;
375 
376 
377 struct exception_port_action_t {
378 	ipc_port_t port;
379 	_ps_port_action_t *port_action;
380 };
381 
382 struct exec_port_actions {
383 	uint32_t exception_port_count;
384 	uint32_t portwatch_count;
385 	uint32_t registered_count;
386 	struct exception_port_action_t *excport_array;
387 	ipc_port_t *portwatch_array;
388 	ipc_port_t registered_array[TASK_PORT_REGISTER_MAX];
389 };
390 
391 struct image_params;    /* Forward */
392 static int exec_activate_image(struct image_params *imgp);
393 static int exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp);
394 static int load_return_to_errno(load_return_t lrtn);
395 static int execargs_alloc(struct image_params *imgp);
396 static int execargs_free(struct image_params *imgp);
397 static int exec_check_permissions(struct image_params *imgp);
398 static int exec_extract_strings(struct image_params *imgp);
399 static int exec_add_apple_strings(struct image_params *imgp, const load_result_t *load_result, task_t task);
400 static int exec_handle_sugid(struct image_params *imgp);
401 static int sugid_scripts = 0;
402 SYSCTL_INT(_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW | CTLFLAG_LOCKED, &sugid_scripts, 0, "");
403 static kern_return_t create_unix_stack(vm_map_t map, load_result_t* load_result, proc_t p);
404 static int copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size);
405 static void exec_resettextvp(proc_t, struct image_params *);
406 static int process_signature(proc_t, struct image_params *);
407 static void exec_prefault_data(proc_t, struct image_params *, load_result_t *);
408 static errno_t exec_handle_port_actions(struct image_params *imgp,
409     struct exec_port_actions *port_actions);
410 static errno_t exec_handle_exception_port_actions(const struct image_params *imgp,
411     const struct exec_port_actions *port_actions);
412 static errno_t exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
413     task_role_t psa_darwin_role, struct exec_port_actions *port_actions);
414 static void exec_port_actions_destroy(struct exec_port_actions *port_actions);
415 
416 /*
417  * exec_add_user_string
418  *
419  * Add the requested string to the string space area.
420  *
421  * Parameters;	struct image_params *		image parameter block
422  *		user_addr_t			string to add to strings area
423  *		int				segment from which string comes
424  *		boolean_t			TRUE if string contributes to NCARGS
425  *
426  * Returns:	0			Success
427  *		!0			Failure errno from copyinstr()
428  *
429  * Implicit returns:
430  *		(imgp->ip_strendp)	updated location of next add, if any
431  *		(imgp->ip_strspace)	updated byte count of space remaining
432  *		(imgp->ip_argspace) updated byte count of space in NCARGS
433  */
434 __attribute__((noinline))
435 static int
exec_add_user_string(struct image_params * imgp,user_addr_t str,int seg,boolean_t is_ncargs)436 exec_add_user_string(struct image_params *imgp, user_addr_t str, int seg, boolean_t is_ncargs)
437 {
438 	int error = 0;
439 
440 	do {
441 		size_t len = 0;
442 		int space;
443 
444 		if (is_ncargs) {
445 			space = imgp->ip_argspace; /* by definition smaller than ip_strspace */
446 		} else {
447 			space = imgp->ip_strspace;
448 		}
449 
450 		if (space <= 0) {
451 			error = E2BIG;
452 			break;
453 		}
454 
455 		if (!UIO_SEG_IS_USER_SPACE(seg)) {
456 			char *kstr = CAST_DOWN(char *, str);     /* SAFE */
457 			error = copystr(kstr, imgp->ip_strendp, space, &len);
458 		} else {
459 			error = copyinstr(str, imgp->ip_strendp, space, &len);
460 		}
461 
462 		imgp->ip_strendp += len;
463 		imgp->ip_strspace -= len;
464 		if (is_ncargs) {
465 			imgp->ip_argspace -= len;
466 		}
467 	} while (error == ENAMETOOLONG);
468 
469 	return error;
470 }
471 
472 /*
473  * dyld is now passed the executable path as a getenv-like variable
474  * in the same fashion as the stack_guard and malloc_entropy keys.
475  */
476 #define EXECUTABLE_KEY "executable_path="
477 
478 /*
479  * exec_save_path
480  *
481  * To support new app package launching for Mac OS X, the dyld needs the
482  * first argument to execve() stored on the user stack.
483  *
484  * Save the executable path name at the bottom of the strings area and set
485  * the argument vector pointer to the location following that to indicate
486  * the start of the argument and environment tuples, setting the remaining
487  * string space count to the size of the string area minus the path length.
488  *
489  * Parameters;	struct image_params *		image parameter block
490  *		char *				path used to invoke program
491  *		int				segment from which path comes
492  *
493  * Returns:	int			0	Success
494  *		EFAULT				Bad address
495  *	copy[in]str:EFAULT			Bad address
496  *	copy[in]str:ENAMETOOLONG		Filename too long
497  *
498  * Implicit returns:
499  *		(imgp->ip_strings)		saved path
500  *		(imgp->ip_strspace)		space remaining in ip_strings
501  *		(imgp->ip_strendp)		start of remaining copy area
502  *		(imgp->ip_argspace)		space remaining of NCARGS
503  *		(imgp->ip_applec)		Initial applev[0]
504  *
505  * Note:	We have to do this before the initial namei() since in the
506  *		path contains symbolic links, namei() will overwrite the
507  *		original path buffer contents.  If the last symbolic link
508  *		resolved was a relative pathname, we would lose the original
509  *		"path", which could be an absolute pathname. This might be
510  *		unacceptable for dyld.
511  */
512 static int
exec_save_path(struct image_params * imgp,user_addr_t path,int seg,const char ** excpath)513 exec_save_path(struct image_params *imgp, user_addr_t path, int seg, const char **excpath)
514 {
515 	int error;
516 	size_t len;
517 	char *kpath;
518 
519 	// imgp->ip_strings can come out of a cache, so we need to obliterate the
520 	// old path.
521 	memset(imgp->ip_strings, '\0', strlen(EXECUTABLE_KEY) + MAXPATHLEN);
522 
523 	len = MIN(MAXPATHLEN, imgp->ip_strspace);
524 
525 	switch (seg) {
526 	case UIO_USERSPACE32:
527 	case UIO_USERSPACE64:   /* Same for copyin()... */
528 		error = copyinstr(path, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
529 		break;
530 	case UIO_SYSSPACE:
531 		kpath = CAST_DOWN(char *, path); /* SAFE */
532 		error = copystr(kpath, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
533 		break;
534 	default:
535 		error = EFAULT;
536 		break;
537 	}
538 
539 	if (!error) {
540 		bcopy(EXECUTABLE_KEY, imgp->ip_strings, strlen(EXECUTABLE_KEY));
541 		len += strlen(EXECUTABLE_KEY);
542 
543 		imgp->ip_strendp += len;
544 		imgp->ip_strspace -= len;
545 
546 		if (excpath) {
547 			*excpath = imgp->ip_strings + strlen(EXECUTABLE_KEY);
548 		}
549 	}
550 
551 	return error;
552 }
553 
554 /*
555  * exec_reset_save_path
556  *
557  * If we detect a shell script, we need to reset the string area
558  * state so that the interpreter can be saved onto the stack.
559  *
560  * Parameters;	struct image_params *		image parameter block
561  *
562  * Returns:	int			0	Success
563  *
564  * Implicit returns:
565  *		(imgp->ip_strings)		saved path
566  *		(imgp->ip_strspace)		space remaining in ip_strings
567  *		(imgp->ip_strendp)		start of remaining copy area
568  *		(imgp->ip_argspace)		space remaining of NCARGS
569  *
570  */
571 static int
exec_reset_save_path(struct image_params * imgp)572 exec_reset_save_path(struct image_params *imgp)
573 {
574 	imgp->ip_strendp = imgp->ip_strings;
575 	imgp->ip_argspace = NCARGS;
576 	imgp->ip_strspace = (NCARGS + PAGE_SIZE);
577 
578 	return 0;
579 }
580 
581 /*
582  * exec_shell_imgact
583  *
584  * Image activator for interpreter scripts.  If the image begins with
585  * the characters "#!", then it is an interpreter script.  Verify the
586  * length of the script line indicating the interpreter is not in
587  * excess of the maximum allowed size.  If this is the case, then
588  * break out the arguments, if any, which are separated by white
589  * space, and copy them into the argument save area as if they were
590  * provided on the command line before all other arguments.  The line
591  * ends when we encounter a comment character ('#') or newline.
592  *
593  * Parameters;	struct image_params *	image parameter block
594  *
595  * Returns:	-1			not an interpreter (keep looking)
596  *		-3			Success: interpreter: relookup
597  *		>0			Failure: interpreter: error number
598  *
599  * A return value other than -1 indicates subsequent image activators should
600  * not be given the opportunity to attempt to activate the image.
601  */
602 static int
exec_shell_imgact(struct image_params * imgp)603 exec_shell_imgact(struct image_params *imgp)
604 {
605 	char *vdata = imgp->ip_vdata;
606 	char *ihp;
607 	char *line_startp, *line_endp;
608 	char *interp;
609 
610 	/*
611 	 * Make sure it's a shell script.  If we've already redirected
612 	 * from an interpreted file once, don't do it again.
613 	 */
614 	if (vdata[0] != '#' ||
615 	    vdata[1] != '!' ||
616 	    (imgp->ip_flags & IMGPF_INTERPRET) != 0) {
617 		return -1;
618 	}
619 
620 	if (imgp->ip_origcputype != 0) {
621 		/* Fat header previously matched, don't allow shell script inside */
622 		return -1;
623 	}
624 
625 	imgp->ip_flags |= IMGPF_INTERPRET;
626 	imgp->ip_interp_sugid_fd = -1;
627 	imgp->ip_interp_buffer[0] = '\0';
628 
629 	/* Check to see if SUGID scripts are permitted.  If they aren't then
630 	 * clear the SUGID bits.
631 	 * imgp->ip_vattr is known to be valid.
632 	 */
633 	if (sugid_scripts == 0) {
634 		imgp->ip_origvattr->va_mode &= ~(VSUID | VSGID);
635 	}
636 
637 	/* Try to find the first non-whitespace character */
638 	for (ihp = &vdata[2]; ihp < &vdata[IMG_SHSIZE]; ihp++) {
639 		if (IS_EOL(*ihp)) {
640 			/* Did not find interpreter, "#!\n" */
641 			return ENOEXEC;
642 		} else if (IS_WHITESPACE(*ihp)) {
643 			/* Whitespace, like "#!    /bin/sh\n", keep going. */
644 		} else {
645 			/* Found start of interpreter */
646 			break;
647 		}
648 	}
649 
650 	if (ihp == &vdata[IMG_SHSIZE]) {
651 		/* All whitespace, like "#!           " */
652 		return ENOEXEC;
653 	}
654 
655 	line_startp = ihp;
656 
657 	/* Try to find the end of the interpreter+args string */
658 	for (; ihp < &vdata[IMG_SHSIZE]; ihp++) {
659 		if (IS_EOL(*ihp)) {
660 			/* Got it */
661 			break;
662 		} else {
663 			/* Still part of interpreter or args */
664 		}
665 	}
666 
667 	if (ihp == &vdata[IMG_SHSIZE]) {
668 		/* A long line, like "#! blah blah blah" without end */
669 		return ENOEXEC;
670 	}
671 
672 	/* Backtrack until we find the last non-whitespace */
673 	while (IS_EOL(*ihp) || IS_WHITESPACE(*ihp)) {
674 		ihp--;
675 	}
676 
677 	/* The character after the last non-whitespace is our logical end of line */
678 	line_endp = ihp + 1;
679 
680 	/*
681 	 * Now we have pointers to the usable part of:
682 	 *
683 	 * "#!  /usr/bin/int first    second   third    \n"
684 	 *      ^ line_startp                       ^ line_endp
685 	 */
686 
687 	/* copy the interpreter name */
688 	interp = imgp->ip_interp_buffer;
689 	for (ihp = line_startp; (ihp < line_endp) && !IS_WHITESPACE(*ihp); ihp++) {
690 		*interp++ = *ihp;
691 	}
692 	*interp = '\0';
693 
694 	exec_reset_save_path(imgp);
695 	exec_save_path(imgp, CAST_USER_ADDR_T(imgp->ip_interp_buffer),
696 	    UIO_SYSSPACE, NULL);
697 
698 	/* Copy the entire interpreter + args for later processing into argv[] */
699 	interp = imgp->ip_interp_buffer;
700 	for (ihp = line_startp; (ihp < line_endp); ihp++) {
701 		*interp++ = *ihp;
702 	}
703 	*interp = '\0';
704 
705 #if CONFIG_SETUID
706 	/*
707 	 * If we have an SUID or SGID script, create a file descriptor
708 	 * from the vnode and pass /dev/fd/%d instead of the actual
709 	 * path name so that the script does not get opened twice
710 	 */
711 	if (imgp->ip_origvattr->va_mode & (VSUID | VSGID)) {
712 		proc_t p;
713 		struct fileproc *fp;
714 		int fd;
715 		int error;
716 
717 		p = vfs_context_proc(imgp->ip_vfs_context);
718 		error = falloc_exec(p, imgp->ip_vfs_context, &fp, &fd);
719 		if (error) {
720 			return error;
721 		}
722 
723 		fp->fp_glob->fg_flag = FREAD;
724 		fp->fp_glob->fg_ops = &vnops;
725 		fp_set_data(fp, imgp->ip_vp);
726 
727 		proc_fdlock(p);
728 		procfdtbl_releasefd(p, fd, NULL);
729 		fp_drop(p, fd, fp, 1);
730 		proc_fdunlock(p);
731 		vnode_ref(imgp->ip_vp);
732 
733 		imgp->ip_interp_sugid_fd = fd;
734 	}
735 #endif /* CONFIG_SETUID */
736 
737 	return -3;
738 }
739 
740 
741 
742 /*
743  * exec_fat_imgact
744  *
745  * Image activator for fat 1.0 binaries.  If the binary is fat, then we
746  * need to select an image from it internally, and make that the image
747  * we are going to attempt to execute.  At present, this consists of
748  * reloading the first page for the image with a first page from the
749  * offset location indicated by the fat header.
750  *
751  * Parameters;	struct image_params *	image parameter block
752  *
753  * Returns:	-1			not a fat binary (keep looking)
754  *		-2			Success: encapsulated binary: reread
755  *		>0			Failure: error number
756  *
757  * Important:	This image activator is byte order neutral.
758  *
759  * Note:	A return value other than -1 indicates subsequent image
760  *		activators should not be given the opportunity to attempt
761  *		to activate the image.
762  *
763  *              If we find an encapsulated binary, we make no assertions
764  *		about its  validity; instead, we leave that up to a rescan
765  *		for an activator to claim it, and, if it is claimed by one,
766  *		that activator is responsible for determining validity.
767  */
768 static int
exec_fat_imgact(struct image_params * imgp)769 exec_fat_imgact(struct image_params *imgp)
770 {
771 	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
772 	kauth_cred_t cred = kauth_cred_proc_ref(p);
773 	struct fat_header *fat_header = (struct fat_header *)imgp->ip_vdata;
774 	struct _posix_spawnattr *psa = NULL;
775 	struct fat_arch fat_arch;
776 	int resid, error;
777 	load_return_t lret;
778 
779 	if (imgp->ip_origcputype != 0) {
780 		/* Fat header previously matched, don't allow another fat file inside */
781 		error = -1; /* not claimed */
782 		goto bad;
783 	}
784 
785 	/* Make sure it's a fat binary */
786 	if (OSSwapBigToHostInt32(fat_header->magic) != FAT_MAGIC) {
787 		error = -1; /* not claimed */
788 		goto bad;
789 	}
790 
791 	/* imgp->ip_vdata has PAGE_SIZE, zerofilled if the file is smaller */
792 	lret = fatfile_validate_fatarches((vm_offset_t)fat_header, PAGE_SIZE,
793 	    (off_t)imgp->ip_vattr->va_data_size);
794 	if (lret != LOAD_SUCCESS) {
795 		error = load_return_to_errno(lret);
796 		goto bad;
797 	}
798 
799 	/* If posix_spawn binprefs exist, respect those prefs. */
800 	psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
801 	if (psa != NULL && psa->psa_binprefs[0] != 0) {
802 		uint32_t pr = 0;
803 
804 		/* Check each preference listed against all arches in header */
805 		for (pr = 0; pr < NBINPREFS; pr++) {
806 			cpu_type_t pref = psa->psa_binprefs[pr];
807 			cpu_type_t subpref = psa->psa_subcpuprefs[pr];
808 
809 			if (pref == 0) {
810 				/* No suitable arch in the pref list */
811 				error = EBADARCH;
812 				goto bad;
813 			}
814 
815 			if (pref == CPU_TYPE_ANY) {
816 				/* Fall through to regular grading */
817 				goto regular_grading;
818 			}
819 
820 			lret = fatfile_getbestarch_for_cputype(pref,
821 			    subpref,
822 			    (vm_offset_t)fat_header,
823 			    PAGE_SIZE,
824 			    imgp,
825 			    &fat_arch);
826 			if (lret == LOAD_SUCCESS) {
827 				goto use_arch;
828 			}
829 		}
830 
831 		/* Requested binary preference was not honored */
832 		error = EBADEXEC;
833 		goto bad;
834 	}
835 
836 regular_grading:
837 	/* Look up our preferred architecture in the fat file. */
838 	lret = fatfile_getbestarch((vm_offset_t)fat_header,
839 	    PAGE_SIZE,
840 	    imgp,
841 	    &fat_arch,
842 	    (p->p_flag & P_AFFINITY) != 0);
843 	if (lret != LOAD_SUCCESS) {
844 		error = load_return_to_errno(lret);
845 		goto bad;
846 	}
847 
848 use_arch:
849 	/* Read the Mach-O header out of fat_arch */
850 	error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata,
851 	    PAGE_SIZE, fat_arch.offset,
852 	    UIO_SYSSPACE, (IO_UNIT | IO_NODELOCKED),
853 	    cred, &resid, p);
854 	if (error) {
855 		if (error == ERESTART) {
856 			error = EINTR;
857 		}
858 		goto bad;
859 	}
860 
861 	if (resid) {
862 		memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
863 	}
864 
865 	/* Success.  Indicate we have identified an encapsulated binary */
866 	error = -2;
867 	imgp->ip_arch_offset = (user_size_t)fat_arch.offset;
868 	imgp->ip_arch_size = (user_size_t)fat_arch.size;
869 	imgp->ip_origcputype = fat_arch.cputype;
870 	imgp->ip_origcpusubtype = fat_arch.cpusubtype;
871 
872 bad:
873 	kauth_cred_unref(&cred);
874 	return error;
875 }
876 
877 static int
activate_exec_state(task_t task,proc_t p,thread_t thread,load_result_t * result)878 activate_exec_state(task_t task, proc_t p, thread_t thread, load_result_t *result)
879 {
880 	int ret;
881 
882 	(void)task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0, false);
883 	task_set_64bit(task, result->is_64bit_addr, result->is_64bit_data);
884 	if (result->is_64bit_addr) {
885 		OSBitOrAtomic(P_LP64, &p->p_flag);
886 		get_bsdthread_info(thread)->uu_flag |= UT_LP64;
887 	} else {
888 		OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag);
889 		get_bsdthread_info(thread)->uu_flag &= ~UT_LP64;
890 	}
891 	task_set_mach_header_address(task, result->mach_header);
892 
893 	ret = thread_state_initialize(thread);
894 	if (ret != KERN_SUCCESS) {
895 		return ret;
896 	}
897 
898 	if (result->threadstate) {
899 		uint32_t *ts = result->threadstate;
900 		uint32_t total_size = (uint32_t)result->threadstate_sz;
901 
902 		while (total_size > 0) {
903 			uint32_t flavor = *ts++;
904 			uint32_t size = *ts++;
905 
906 			ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
907 			if (ret) {
908 				return ret;
909 			}
910 			ts += size;
911 			total_size -= (size + 2) * sizeof(uint32_t);
912 		}
913 	}
914 
915 	thread_setentrypoint(thread, result->entry_point);
916 
917 	return KERN_SUCCESS;
918 }
919 
920 #if (DEVELOPMENT || DEBUG)
921 extern char panic_on_proc_crash[];
922 extern int use_panic_on_proc_crash;
923 
924 extern char panic_on_proc_exit[];
925 extern int use_panic_on_proc_exit;
926 
927 extern char panic_on_proc_spawn_fail[];
928 extern int use_panic_on_proc_spawn_fail;
929 
930 static inline void
set_crash_behavior_from_bootarg(proc_t p)931 set_crash_behavior_from_bootarg(proc_t p)
932 {
933 	if (use_panic_on_proc_crash && strcmp(p->p_comm, panic_on_proc_crash) == 0) {
934 		printf("will panic on proc crash: %s\n", p->p_comm);
935 		p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_CRASH;
936 	}
937 
938 	if (use_panic_on_proc_exit && strcmp(p->p_comm, panic_on_proc_exit) == 0) {
939 		printf("will panic on proc exit: %s\n", p->p_comm);
940 		p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_EXIT;
941 	}
942 
943 	if (use_panic_on_proc_spawn_fail && strcmp(p->p_comm, panic_on_proc_spawn_fail) == 0) {
944 		printf("will panic on proc spawn fail: %s\n", p->p_comm);
945 		p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_SPAWN_FAIL;
946 	}
947 }
948 #endif
949 
950 void
set_proc_name(struct image_params * imgp,proc_t p)951 set_proc_name(struct image_params *imgp, proc_t p)
952 {
953 	uint64_t buflen = imgp->ip_ndp->ni_cnd.cn_namelen;
954 	const int p_name_len = sizeof(p->p_name) - 1;
955 	const int p_comm_len = sizeof(p->p_comm) - 1;
956 
957 	if (buflen > p_name_len) {
958 		buflen = p_name_len;
959 	}
960 
961 	bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_name, buflen);
962 	p->p_name[buflen] = '\0';
963 
964 	if (buflen > p_comm_len) {
965 		static_assert(MAXCOMLEN + 1 == sizeof(p->p_comm));
966 		buflen = p_comm_len;
967 	}
968 
969 	bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_comm, buflen);
970 	p->p_comm[buflen] = '\0';
971 
972 #if (DEVELOPMENT || DEBUG)
973 	/*
974 	 * This happens during image activation, so the crash behavior flags from
975 	 * posix_spawn will have already been set. So we don't have to worry about
976 	 * this being overridden.
977 	 */
978 	set_crash_behavior_from_bootarg(p);
979 #endif
980 }
981 
982 #if __has_feature(ptrauth_calls)
983 /**
984  * Returns a team ID string that may be used to assign a shared region.
985  *
986  * Platform binaries do not have team IDs and will return NULL.  Non-platform
987  * binaries without a team ID will be assigned an artificial team ID of ""
988  * (empty string) so that they will not be assigned to the default shared
989  * region.
990  *
991  * @param imgp image parameter block
992  * @return NULL if this is a platform binary, or an appropriate team ID string
993  *         otherwise
994  */
995 static inline const char *
get_teamid_for_shared_region(struct image_params * imgp)996 get_teamid_for_shared_region(struct image_params *imgp)
997 {
998 	assert(imgp->ip_vp != NULL);
999 
1000 	const char *ret = csvnode_get_teamid(imgp->ip_vp, imgp->ip_arch_offset);
1001 	if (ret) {
1002 		return ret;
1003 	}
1004 
1005 	struct cs_blob *blob = csvnode_get_blob(imgp->ip_vp, imgp->ip_arch_offset);
1006 	if (csblob_get_platform_binary(blob)) {
1007 		return NULL;
1008 	} else {
1009 		static const char *NO_TEAM_ID = "";
1010 		return NO_TEAM_ID;
1011 	}
1012 }
1013 
1014 /**
1015  * Determines whether ptrauth should be enabled for the provided arm64 CPU subtype.
1016  *
1017  * @param cpusubtype Mach-O style CPU subtype
1018  * @return whether the CPU subtype matches arm64e with the current ptrauth ABI
1019  */
1020 static inline bool
arm64_cpusubtype_uses_ptrauth(cpu_subtype_t cpusubtype)1021 arm64_cpusubtype_uses_ptrauth(cpu_subtype_t cpusubtype)
1022 {
1023 	int ptrauth_abi_version = (int)CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(cpusubtype);
1024 	return (cpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
1025 	       (ptrauth_abi_version >= CPU_SUBTYPE_ARM64_PTR_AUTHV0_VERSION &&
1026 	       ptrauth_abi_version <= CPU_SUBTYPE_ARM64_PTR_AUTH_MAX_PREFERRED_VERSION);
1027 }
1028 
1029 #endif /* __has_feature(ptrauth_calls) */
1030 
1031 /**
1032  * Returns whether a type/subtype slice matches the requested
1033  * type/subtype.
1034  *
1035  * @param mask Bits to mask from the requested/tested cpu type
1036  * @param req_cpu Requested cpu type
1037  * @param req_subcpu Requested cpu subtype
1038  * @param test_cpu Tested slice cpu type
1039  * @param test_subcpu Tested slice cpu subtype
1040  */
1041 boolean_t
binary_match(cpu_type_t mask,cpu_type_t req_cpu,cpu_subtype_t req_subcpu,cpu_type_t test_cpu,cpu_subtype_t test_subcpu)1042 binary_match(cpu_type_t mask, cpu_type_t req_cpu,
1043     cpu_subtype_t req_subcpu, cpu_type_t test_cpu,
1044     cpu_subtype_t test_subcpu)
1045 {
1046 	if ((test_cpu & ~mask) != (req_cpu & ~mask)) {
1047 		return FALSE;
1048 	}
1049 
1050 	test_subcpu &= ~CPU_SUBTYPE_MASK;
1051 	req_subcpu  &= ~CPU_SUBTYPE_MASK;
1052 
1053 	if (test_subcpu != req_subcpu && req_subcpu != (CPU_SUBTYPE_ANY & ~CPU_SUBTYPE_MASK)) {
1054 		return FALSE;
1055 	}
1056 
1057 	return TRUE;
1058 }
1059 
1060 
1061 /*
1062  * Check entitlements to see if this is a platform restrictions binary.
1063  * Save this in load_result until later for two purposes:
1064  * 1. We can mark the task at a certain security level once it's been created
1065  * 2. We can propagate which entitlements are present to the apple array
1066  */
1067 static inline void
encode_HR_entitlement(const char * entitlement,hardened_browser_flags_t mask,const struct image_params * imgp,load_result_t * load_result)1068 encode_HR_entitlement(const char *entitlement, hardened_browser_flags_t mask,
1069     const struct image_params *imgp, load_result_t *load_result)
1070 {
1071 	if (IOVnodeHasEntitlement(imgp->ip_vp, (int64_t)imgp->ip_arch_offset, entitlement)) {
1072 		load_result->hardened_browser |= mask;
1073 	}
1074 }
1075 
1076 /*
1077  * If the passed in executable's vnode should use the RSR
1078  * shared region, then this should return TRUE, otherwise, return FALSE.
1079  */
1080 static uint32_t rsr_current_version = 0;
1081 boolean_t (*rsr_check_vnode)(void *vnode) = NULL;
1082 
1083 boolean_t
vnode_is_rsr(vnode_t vp)1084 vnode_is_rsr(vnode_t vp)
1085 {
1086 	if (!(vnode_isreg(vp) && vnode_tag(vp) == VT_APFS)) {
1087 		return FALSE;
1088 	}
1089 
1090 	if (rsr_check_vnode != NULL && rsr_check_vnode((void *)vp)) {
1091 		return TRUE;
1092 	}
1093 	return FALSE;
1094 }
1095 
1096 static struct {
1097 	char *legacy;
1098 	char *security;
1099 } exec_security_mitigation_entitlement[] = {
1100 	/* The following entries must match the enum declaration in kern_exec_internal.h */
1101 	[HARDENED_PROCESS] = {
1102 		"com.apple.developer.hardened-process",
1103 		"com.apple.security.hardened-process"
1104 	},
1105 	[HARDENED_HEAP] = {
1106 		"com.apple.developer.hardened-process.hardened-heap",
1107 		"com.apple.security.hardened-process.hardened-heap"
1108 	},
1109 	[TPRO] = {
1110 		NULL,
1111 		"com.apple.security.hardened-process.dyld-ro",
1112 	},
1113 };
1114 
1115 /*
1116  * Platform Restrictions
1117  *
1118  * This mitigation opts you into the grab bag of various kernel mitigations
1119  * including IPC security restrictions
1120  * The presence of the entitlement opts the binary into the feature.
1121  * The entitlement is an <integer> entitlement containing a version number
1122  * for the platform restrictions you are opting into.
1123  */
1124 #define SPAWN_ENABLE_PLATFORM_RESTRICTIONS "com.apple.security.hardened-process.platform-restrictions"
1125 
1126 /*
1127  * Version number for enhanced security
1128  * Currently stored with 3 bits in `hardened_process_version`
1129  */
1130 #define HARDENED_PROCESS_VERSION "com.apple.security.hardened-process.enhanced-security-version"
1131 
1132 /* See kern_exec_internal.h for the extensive documentation. */
1133 exec_security_err_t
exec_check_security_entitlement(struct image_params * imgp,exec_security_mitigation_entitlement_t entitlement)1134 exec_check_security_entitlement(struct image_params *imgp,
1135     exec_security_mitigation_entitlement_t entitlement)
1136 {
1137 	bool has_legacy_entitlement = false, has_security_entitlement = false;
1138 	assert(exec_security_mitigation_entitlement[entitlement].security != NULL);
1139 
1140 	if (exec_security_mitigation_entitlement[entitlement].legacy != NULL) {
1141 		has_legacy_entitlement =
1142 		    IOVnodeHasEntitlement(imgp->ip_vp, (int64_t)imgp->ip_arch_offset,
1143 		    exec_security_mitigation_entitlement[entitlement].legacy);
1144 	}
1145 
1146 	has_security_entitlement =
1147 	    IOVnodeHasEntitlement(imgp->ip_vp, (int64_t)imgp->ip_arch_offset,
1148 	    exec_security_mitigation_entitlement[entitlement].security);
1149 
1150 	/* If both entitlements are present, this is an invalid configuration. */
1151 	if (has_legacy_entitlement && has_security_entitlement) {
1152 		EXEC_LOG("Binary has both legacy (%s) and security (%s) entitlements\n",
1153 		    exec_security_mitigation_entitlement[entitlement].legacy,
1154 		    exec_security_mitigation_entitlement[entitlement].security);
1155 
1156 		return EXEC_SECURITY_INVALID_CONFIG;
1157 	}
1158 
1159 	if (has_legacy_entitlement || has_security_entitlement) {
1160 		return EXEC_SECURITY_ENTITLED;
1161 	}
1162 
1163 	return EXEC_SECURITY_NOT_ENTITLED;
1164 }
1165 
1166 
1167 /*
1168  * Entitled binaries get hardened_heap
1169  */
1170 static inline errno_t
imgact_setup_hardened_heap(struct image_params * imgp,task_t task)1171 imgact_setup_hardened_heap(struct image_params *imgp, task_t task)
1172 {
1173 	exec_security_err_t ret = exec_check_security_entitlement(imgp, HARDENED_HEAP);
1174 	if (ret == EXEC_SECURITY_ENTITLED) {
1175 		task_set_hardened_heap(task);
1176 	} else {
1177 		task_clear_hardened_heap(task);
1178 	}
1179 	switch (ret) {
1180 	case EXEC_SECURITY_INVALID_CONFIG:
1181 		return EINVAL;
1182 	case EXEC_SECURITY_ENTITLED:
1183 	case EXEC_SECURITY_NOT_ENTITLED:
1184 		return 0;
1185 	}
1186 }
1187 
1188 /*
1189  * Configure the platform restrictions security features on the task
1190  * This must be done before `ipc_task_enable` so that the bits
1191  * can be propogated to the ipc space.
1192  *
1193  * Requires `exectextresetvp` to be called on `task` previously so
1194  * that we can use the `IOTaskGetEntitlement` API
1195  */
1196 static inline void
exec_setup_platform_restrictions(task_t task)1197 exec_setup_platform_restrictions(task_t task)
1198 {
1199 	uint64_t value = 0;
1200 	/* Set platform restrictions version */
1201 	if (task_get_platform_binary(task)) {
1202 		task_set_platform_restrictions_version(task, 2);
1203 	} else if (IOTaskGetIntegerEntitlement(task, SPAWN_ENABLE_PLATFORM_RESTRICTIONS, &value) &&
1204 	    value > 1) {
1205 		task_set_platform_restrictions_version(task, value);
1206 	}
1207 
1208 	/* Set hardened process version*/
1209 	if (IOTaskGetIntegerEntitlement(task, HARDENED_PROCESS_VERSION, &value)) {
1210 		task_set_hardened_process_version(task, value);
1211 	}
1212 }
1213 
1214 
1215 /*
1216  * This routine configures the various runtime mitigations we can apply to a process
1217  * during image activation. This occurs before `imgact_setup_runtime_mitigations`
1218  *
1219  * Returns true on success, false on failure. Failure will be fatal in exec_mach_imgact().
1220  */
1221 static inline errno_t
imgact_setup_runtime_mitigations(struct image_params * imgp,__unused load_result_t * load_result,__unused task_t old_task,task_t new_task,__unused vm_map_t map,__unused proc_t proc)1222 imgact_setup_runtime_mitigations(struct image_params *imgp, __unused load_result_t *load_result,
1223     __unused task_t old_task, task_t new_task, __unused vm_map_t map, __unused proc_t proc)
1224 {
1225 	/*
1226 	 * It's safe to check entitlements anytime after `load_machfile` if you check
1227 	 * based on the vnode in imgp. We must perform this entitlement check
1228 	 * before we start using load_result->hardened_browser further down
1229 	 */
1230 	load_result->hardened_browser = 0;
1231 	encode_HR_entitlement(kCSWebBrowserHostEntitlement, BrowserHostEntitlementMask, imgp, load_result);
1232 	encode_HR_entitlement(kCSWebBrowserGPUEntitlement, BrowserGPUEntitlementMask, imgp, load_result);
1233 	encode_HR_entitlement(kCSWebBrowserNetworkEntitlement, BrowserNetworkEntitlementMask, imgp, load_result);
1234 	encode_HR_entitlement(kCSWebBrowserWebContentEntitlement, BrowserWebContentEntitlementMask, imgp, load_result);
1235 
1236 	if (load_result->hardened_browser) {
1237 		task_set_platform_restrictions_version(new_task, 1);
1238 	}
1239 
1240 	errno_t retval = 0;
1241 
1242 	/*
1243 	 * Hardened-heap enables a set of extra security features in our system memory allocator.
1244 	 */
1245 	if ((retval = imgact_setup_hardened_heap(imgp, new_task)) != 0) {
1246 		EXEC_LOG("Invalid configuration detected for hardened-heap");
1247 		return retval;
1248 	}
1249 
1250 
1251 
1252 
1253 	return retval;
1254 }
1255 
1256 uint32_t
rsr_get_version(void)1257 rsr_get_version(void)
1258 {
1259 	return os_atomic_load(&rsr_current_version, relaxed);
1260 }
1261 
1262 void
rsr_bump_version(void)1263 rsr_bump_version(void)
1264 {
1265 	os_atomic_inc(&rsr_current_version, relaxed);
1266 }
1267 
1268 #if XNU_TARGET_OS_OSX
1269 static int
1270 rsr_version_sysctl SYSCTL_HANDLER_ARGS
1271 {
1272 #pragma unused(arg1, arg2, oidp)
1273 	int value = rsr_get_version();
1274 	int error = SYSCTL_OUT(req, &value, sizeof(int));
1275 	if (error) {
1276 		return error;
1277 	}
1278 
1279 	if (!req->newptr) {
1280 		return 0;
1281 	}
1282 
1283 	error = SYSCTL_IN(req, &value, sizeof(int));
1284 	if (error) {
1285 		return error;
1286 	}
1287 	if (value != 0) {
1288 		rsr_bump_version();
1289 	}
1290 	return 0;
1291 }
1292 
1293 
1294 SYSCTL_PROC(_vm, OID_AUTO, shared_region_control,
1295     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_MASKED,
1296     0, 0, rsr_version_sysctl, "I", "");
1297 #endif /* XNU_TARGET_OS_OSX */
1298 
1299 /*
1300  * exec_mach_imgact
1301  *
1302  * Image activator for mach-o 1.0 binaries.
1303  *
1304  * Parameters;	struct image_params *	image parameter block
1305  *
1306  * Returns:	-1			not a fat binary (keep looking)
1307  *		-2			Success: encapsulated binary: reread
1308  *		>0			Failure: error number
1309  *		EBADARCH		Mach-o binary, but with an unrecognized
1310  *					architecture
1311  *		ENOMEM			No memory for child process after -
1312  *					can only happen after vfork()
1313  *
1314  * Important:	This image activator is NOT byte order neutral.
1315  *
1316  * Note:	A return value other than -1 indicates subsequent image
1317  *		activators should not be given the opportunity to attempt
1318  *		to activate the image.
1319  */
1320 static int
exec_mach_imgact(struct image_params * imgp)1321 exec_mach_imgact(struct image_params *imgp)
1322 {
1323 	struct mach_header *mach_header = (struct mach_header *)imgp->ip_vdata;
1324 	proc_t                  p = vfs_context_proc(imgp->ip_vfs_context);
1325 	int                     error = 0;
1326 	task_t                  task;
1327 	task_t                  new_task = NULL;    /* protected by vfexec */
1328 	thread_t                thread;
1329 	struct uthread          *uthread;
1330 	vm_map_switch_context_t switch_ctx;
1331 	vm_map_t old_map = VM_MAP_NULL;
1332 	vm_map_t map = VM_MAP_NULL;
1333 	load_return_t           lret;
1334 	load_result_t           load_result = {};
1335 	struct _posix_spawnattr *psa = NULL;
1336 	int                     spawn = (imgp->ip_flags & IMGPF_SPAWN);
1337 	const int               vfexec = 0;
1338 	int                     exec = (imgp->ip_flags & IMGPF_EXEC);
1339 	os_reason_t             exec_failure_reason = OS_REASON_NULL;
1340 	boolean_t               reslide = FALSE;
1341 	char *                  userspace_coredump_name = NULL;
1342 
1343 	/*
1344 	 * make sure it's a Mach-O 1.0 or Mach-O 2.0 binary; the difference
1345 	 * is a reserved field on the end, so for the most part, we can
1346 	 * treat them as if they were identical. Reverse-endian Mach-O
1347 	 * binaries are recognized but not compatible.
1348 	 */
1349 	if ((mach_header->magic == MH_CIGAM) ||
1350 	    (mach_header->magic == MH_CIGAM_64)) {
1351 		error = EBADARCH;
1352 		goto bad;
1353 	}
1354 
1355 	if ((mach_header->magic != MH_MAGIC) &&
1356 	    (mach_header->magic != MH_MAGIC_64)) {
1357 		error = -1;
1358 		goto bad;
1359 	}
1360 
1361 	if (mach_header->filetype != MH_EXECUTE) {
1362 		error = -1;
1363 		goto bad;
1364 	}
1365 
1366 	if (imgp->ip_origcputype != 0) {
1367 		/* Fat header previously had an idea about this thin file */
1368 		if (imgp->ip_origcputype != mach_header->cputype ||
1369 		    imgp->ip_origcpusubtype != mach_header->cpusubtype) {
1370 			error = EBADARCH;
1371 			goto bad;
1372 		}
1373 	} else {
1374 		imgp->ip_origcputype = mach_header->cputype;
1375 		imgp->ip_origcpusubtype = mach_header->cpusubtype;
1376 	}
1377 
1378 	task = current_task();
1379 	thread = current_thread();
1380 	uthread = get_bsdthread_info(thread);
1381 
1382 	if ((mach_header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64) {
1383 		imgp->ip_flags |= IMGPF_IS_64BIT_ADDR | IMGPF_IS_64BIT_DATA;
1384 	}
1385 
1386 
1387 	/* If posix_spawn binprefs exist, respect those prefs. */
1388 	psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
1389 	if (psa != NULL && psa->psa_binprefs[0] != 0) {
1390 		int pr = 0;
1391 		for (pr = 0; pr < NBINPREFS; pr++) {
1392 			cpu_type_t pref = psa->psa_binprefs[pr];
1393 			cpu_subtype_t subpref = psa->psa_subcpuprefs[pr];
1394 
1395 			if (pref == 0) {
1396 				/* No suitable arch in the pref list */
1397 				error = EBADARCH;
1398 				goto bad;
1399 			}
1400 
1401 			if (pref == CPU_TYPE_ANY) {
1402 				/* Jump to regular grading */
1403 				goto grade;
1404 			}
1405 
1406 			if (binary_match(CPU_ARCH_MASK, pref, subpref,
1407 			    imgp->ip_origcputype, imgp->ip_origcpusubtype)) {
1408 				goto grade;
1409 			}
1410 		}
1411 		error = EBADARCH;
1412 		goto bad;
1413 	}
1414 grade:
1415 	if (!grade_binary(imgp->ip_origcputype, imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK,
1416 	    imgp->ip_origcpusubtype & CPU_SUBTYPE_MASK, TRUE)) {
1417 		error = EBADARCH;
1418 		goto bad;
1419 	}
1420 
1421 	if (validate_potential_simulator_binary(imgp->ip_origcputype, imgp,
1422 	    imgp->ip_arch_offset, imgp->ip_arch_size) != LOAD_SUCCESS) {
1423 #if __x86_64__
1424 		const char *excpath;
1425 		error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
1426 		os_log_error(OS_LOG_DEFAULT, "Unsupported 32-bit executable: \"%s\"", (error) ? imgp->ip_vp->v_name : excpath);
1427 #endif
1428 		error = EBADARCH;
1429 		goto bad;
1430 	}
1431 
1432 #if defined(HAS_APPLE_PAC)
1433 	assert(mach_header->cputype == CPU_TYPE_ARM64
1434 	    );
1435 
1436 	if ((mach_header->cputype == CPU_TYPE_ARM64 &&
1437 	    arm64_cpusubtype_uses_ptrauth(mach_header->cpusubtype))
1438 	    ) {
1439 		imgp->ip_flags &= ~IMGPF_NOJOP;
1440 	} else {
1441 		imgp->ip_flags |= IMGPF_NOJOP;
1442 	}
1443 #endif
1444 
1445 	/* Copy in arguments/environment from the old process */
1446 	error = exec_extract_strings(imgp);
1447 	if (error) {
1448 		goto bad;
1449 	}
1450 
1451 	AUDIT_ARG(argv, imgp->ip_startargv, imgp->ip_argc,
1452 	    imgp->ip_endargv - imgp->ip_startargv);
1453 	AUDIT_ARG(envv, imgp->ip_endargv, imgp->ip_envc,
1454 	    imgp->ip_endenvv - imgp->ip_endargv);
1455 
1456 	/* reset local idea of thread, uthread, task */
1457 	thread = imgp->ip_new_thread;
1458 	uthread = get_bsdthread_info(thread);
1459 	task = new_task = get_threadtask(thread);
1460 
1461 	/*
1462 	 *	Load the Mach-O file.
1463 	 *
1464 	 * NOTE: An error after this point  indicates we have potentially
1465 	 * destroyed or overwritten some process state while attempting an
1466 	 * execve() following a vfork(), which is an unrecoverable condition.
1467 	 * We send the new process an immediate SIGKILL to avoid it executing
1468 	 * any instructions in the mutated address space. For true spawns,
1469 	 * this is not the case, and "too late" is still not too late to
1470 	 * return an error code to the parent process.
1471 	 */
1472 
1473 	/*
1474 	 * Actually load the image file we previously decided to load.
1475 	 */
1476 	lret = load_machfile(imgp, mach_header, thread, &map, &load_result);
1477 	if (lret != LOAD_SUCCESS) {
1478 		error = load_return_to_errno(lret);
1479 
1480 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1481 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO, 0, 0);
1482 		if (lret == LOAD_BADMACHO_UPX) {
1483 			set_proc_name(imgp, p);
1484 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_UPX);
1485 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1486 		} else {
1487 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1488 
1489 			if (bootarg_execfailurereports) {
1490 				set_proc_name(imgp, p);
1491 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1492 			}
1493 		}
1494 
1495 		exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1496 
1497 		goto badtoolate;
1498 	}
1499 
1500 	assert(imgp->ip_free_map == NULL);
1501 
1502 	/*
1503 	 * ERROR RECOVERY
1504 	 *
1505 	 * load_machfile() returned the new VM map ("map") but we haven't
1506 	 * committed to it yet.
1507 	 * Any error path between here and the point where we commit to using
1508 	 * the new "map" (with swap_task_map()) should deallocate "map".
1509 	 */
1510 
1511 #ifndef KASAN
1512 	/*
1513 	 * Security: zone sanity checks on fresh boot or initproc re-exec.
1514 	 * launchd by design does not tear down its own service port on USR (rdar://72797967),
1515 	 * which means here is the earliest point we can assert on empty service port label zone,
1516 	 * after load_machfile() above terminates old launchd's IPC space.
1517 	 *
1518 	 * Disable on KASAN builds since zone_size_allocated() accounts for elements
1519 	 * under quarantine.
1520 	 */
1521 	if (task_pid(task) == 1) {
1522 		zone_userspace_reboot_checks();
1523 	}
1524 #endif
1525 
1526 	proc_lock(p);
1527 	p->p_cputype = imgp->ip_origcputype;
1528 	p->p_cpusubtype = imgp->ip_origcpusubtype;
1529 	proc_setplatformdata(p, load_result.ip_platform, load_result.lr_min_sdk, load_result.lr_sdk);
1530 
1531 	vm_map_set_size_limit(map, proc_limitgetcur(p, RLIMIT_AS));
1532 	vm_map_set_data_limit(map, proc_limitgetcur(p, RLIMIT_DATA));
1533 	vm_map_set_user_wire_limit(map, (vm_size_t)proc_limitgetcur(p, RLIMIT_MEMLOCK));
1534 
1535 #if XNU_TARGET_OS_OSX
1536 	if (proc_platform(p) == PLATFORM_IOS) {
1537 		assert(vm_map_is_alien(map));
1538 	} else {
1539 		assert(!vm_map_is_alien(map));
1540 	}
1541 #endif /* XNU_TARGET_OS_OSX */
1542 	proc_unlock(p);
1543 
1544 	/*
1545 	 * Setup runtime mitigations.
1546 	 */
1547 	if ((error = imgact_setup_runtime_mitigations(imgp, &load_result, current_task(), new_task, map, p)) != 0) {
1548 		set_proc_name(imgp, p);
1549 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1550 		if (bootarg_execfailurereports) {
1551 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1552 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1553 		}
1554 		/* release new address space since we won't use it */
1555 		imgp->ip_free_map = map;
1556 		map = VM_MAP_NULL;
1557 		goto badtoolate;
1558 	}
1559 
1560 	/*
1561 	 * Set code-signing flags if this binary is signed, or if parent has
1562 	 * requested them on exec.
1563 	 */
1564 	if (load_result.csflags & CS_VALID) {
1565 		imgp->ip_csflags |= load_result.csflags &
1566 		    (CS_VALID | CS_SIGNED | CS_DEV_CODE | CS_LINKER_SIGNED |
1567 		    CS_HARD | CS_KILL | CS_RESTRICT | CS_ENFORCEMENT | CS_REQUIRE_LV |
1568 		    CS_FORCED_LV | CS_ENTITLEMENTS_VALIDATED | CS_NO_UNTRUSTED_HELPERS | CS_RUNTIME |
1569 		    CS_ENTITLEMENT_FLAGS |
1570 		    CS_EXEC_SET_HARD | CS_EXEC_SET_KILL | CS_EXEC_SET_ENFORCEMENT);
1571 	} else {
1572 		imgp->ip_csflags &= ~CS_VALID;
1573 	}
1574 
1575 	if (proc_getcsflags(p) & CS_EXEC_SET_HARD) {
1576 		imgp->ip_csflags |= CS_HARD;
1577 	}
1578 	if (proc_getcsflags(p) & CS_EXEC_SET_KILL) {
1579 		imgp->ip_csflags |= CS_KILL;
1580 	}
1581 	if (proc_getcsflags(p) & CS_EXEC_SET_ENFORCEMENT) {
1582 		imgp->ip_csflags |= CS_ENFORCEMENT;
1583 	}
1584 	if (proc_getcsflags(p) & CS_EXEC_INHERIT_SIP) {
1585 		if (proc_getcsflags(p) & CS_INSTALLER) {
1586 			imgp->ip_csflags |= CS_INSTALLER;
1587 		}
1588 		if (proc_getcsflags(p) & CS_DATAVAULT_CONTROLLER) {
1589 			imgp->ip_csflags |= CS_DATAVAULT_CONTROLLER;
1590 		}
1591 		if (proc_getcsflags(p) & CS_NVRAM_UNRESTRICTED) {
1592 			imgp->ip_csflags |= CS_NVRAM_UNRESTRICTED;
1593 		}
1594 	}
1595 
1596 #if __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX)
1597 	/*
1598 	 * ptrauth version 0 is a preview ABI.  Developers can opt into running
1599 	 * their own arm64e binaries for local testing, with the understanding
1600 	 * that future OSes may break ABI.
1601 	 */
1602 	if ((imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
1603 	    CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(imgp->ip_origcpusubtype) == 0 &&
1604 	    !load_result.platform_binary &&
1605 	    !bootarg_arm64e_preview_abi) {
1606 		static bool logged_once = false;
1607 		set_proc_name(imgp, p);
1608 
1609 		printf("%s: not running binary \"%s\" built against preview arm64e ABI\n", __func__, p->p_name);
1610 		if (!os_atomic_xchg(&logged_once, true, relaxed)) {
1611 			printf("%s: (to allow this, add \"-arm64e_preview_abi\" to boot-args)\n", __func__);
1612 		}
1613 
1614 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1615 		if (bootarg_execfailurereports) {
1616 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1617 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1618 		}
1619 
1620 		/* release new address space since we won't use it */
1621 		imgp->ip_free_map = map;
1622 		map = VM_MAP_NULL;
1623 		goto badtoolate;
1624 	}
1625 
1626 	if ((imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) != CPU_SUBTYPE_ARM64E &&
1627 	    imgp->ip_origcputype == CPU_TYPE_ARM64 &&
1628 	    load_result.platform_binary &&
1629 	    (imgp->ip_flags & IMGPF_DRIVER) != 0) {
1630 		set_proc_name(imgp, p);
1631 		printf("%s: disallowing arm64 platform driverkit binary \"%s\", should be arm64e\n", __func__, p->p_name);
1632 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1633 		if (bootarg_execfailurereports) {
1634 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1635 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1636 		}
1637 
1638 		/* release new address space since we won't use it */
1639 		imgp->ip_free_map = map;
1640 		map = VM_MAP_NULL;
1641 		goto badtoolate;
1642 	}
1643 #endif /* __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX) */
1644 
1645 
1646 
1647 	/*
1648 	 * Set up the shared cache region in the new process.
1649 	 *
1650 	 * Normally there is a single shared region per architecture.
1651 	 * However on systems with Pointer Authentication, we can create
1652 	 * multiple shared caches with the amount of sharing determined
1653 	 * by team-id or entitlement. Inherited shared region IDs are used
1654 	 * for system processes that need to match and be able to inspect
1655 	 * a pre-existing task.
1656 	 */
1657 	int cpu_subtype = 0;     /* all cpu_subtypes use the same shared region */
1658 #if __has_feature(ptrauth_calls)
1659 	char *shared_region_id = NULL;
1660 	size_t len;
1661 	char *base;
1662 	const char *cbase;
1663 #define HARDENED_RUNTIME_CONTENT_ID "C-"
1664 #define TEAM_ID_PREFIX "T-"
1665 #define ENTITLE_PREFIX "E-"
1666 #define SR_PREFIX_LEN  2
1667 #define SR_ENTITLEMENT "com.apple.pac.shared_region_id"
1668 
1669 	if (cpu_type() == CPU_TYPE_ARM64 &&
1670 	    arm64_cpusubtype_uses_ptrauth(p->p_cpusubtype) &&
1671 	    (imgp->ip_flags & IMGPF_NOJOP) == 0) {
1672 		assertf(p->p_cputype == CPU_TYPE_ARM64,
1673 		    "p %p cpu_type() 0x%x p->p_cputype 0x%x p->p_cpusubtype 0x%x",
1674 		    p, cpu_type(), p->p_cputype, p->p_cpusubtype);
1675 
1676 		/*
1677 		 * arm64e uses pointer authentication, so request a separate
1678 		 * shared region for this CPU subtype.
1679 		 */
1680 		cpu_subtype = p->p_cpusubtype & ~CPU_SUBTYPE_MASK;
1681 
1682 		/*
1683 		 * Determine which shared cache to select based on being told,
1684 		 * matching a team-id or matching an entitlement.
1685 		 */
1686 		if (load_result.hardened_browser & BrowserWebContentEntitlementMask) {
1687 			len = sizeof(HARDENED_RUNTIME_CONTENT_ID);
1688 			shared_region_id = kalloc_data(len, Z_WAITOK | Z_NOFAIL);
1689 			strlcpy(shared_region_id, HARDENED_RUNTIME_CONTENT_ID, len);
1690 		} else if (imgp->ip_inherited_shared_region_id) {
1691 			len = strlen(imgp->ip_inherited_shared_region_id);
1692 			shared_region_id = kalloc_data(len + 1, Z_WAITOK | Z_NOFAIL);
1693 			memcpy(shared_region_id, imgp->ip_inherited_shared_region_id, len + 1);
1694 		} else if ((cbase = get_teamid_for_shared_region(imgp)) != NULL) {
1695 			len = strlen(cbase);
1696 			if (vm_shared_region_per_team_id) {
1697 				shared_region_id = kalloc_data(len + SR_PREFIX_LEN + 1,
1698 				    Z_WAITOK | Z_NOFAIL);
1699 				memcpy(shared_region_id, TEAM_ID_PREFIX, SR_PREFIX_LEN);
1700 				memcpy(shared_region_id + SR_PREFIX_LEN, cbase, len + 1);
1701 			}
1702 		} else if ((base = IOVnodeGetEntitlement(imgp->ip_vp,
1703 		    (int64_t)imgp->ip_arch_offset, SR_ENTITLEMENT)) != NULL) {
1704 			len = strlen(base);
1705 			if (vm_shared_region_by_entitlement) {
1706 				shared_region_id = kalloc_data(len + SR_PREFIX_LEN + 1,
1707 				    Z_WAITOK | Z_NOFAIL);
1708 				memcpy(shared_region_id, ENTITLE_PREFIX, SR_PREFIX_LEN);
1709 				memcpy(shared_region_id + SR_PREFIX_LEN, base, len + 1);
1710 			}
1711 			/* Discard the copy of the entitlement */
1712 			kfree_data(base, len + 1);
1713 		}
1714 	}
1715 
1716 	if (imgp->ip_flags & IMGPF_RESLIDE) {
1717 		reslide = TRUE;
1718 	}
1719 
1720 	/* use "" as the default shared_region_id */
1721 	if (shared_region_id == NULL) {
1722 		shared_region_id = kalloc_data(1, Z_WAITOK | Z_ZERO | Z_NOFAIL);
1723 	}
1724 
1725 	/* ensure there's a unique pointer signing key for this shared_region_id */
1726 	shared_region_key_alloc(shared_region_id,
1727 	    imgp->ip_inherited_shared_region_id != NULL, imgp->ip_inherited_jop_pid);
1728 	task_set_shared_region_id(task, shared_region_id);
1729 	shared_region_id = NULL;
1730 #endif /* __has_feature(ptrauth_calls) */
1731 
1732 #if CONFIG_ROSETTA
1733 	if (imgp->ip_flags & IMGPF_ROSETTA) {
1734 		OSBitOrAtomic(P_TRANSLATED, &p->p_flag);
1735 	} else if (p->p_flag & P_TRANSLATED) {
1736 		OSBitAndAtomic(~P_TRANSLATED, &p->p_flag);
1737 	}
1738 #endif
1739 
1740 	int cputype = cpu_type();
1741 
1742 	uint32_t rsr_version = 0;
1743 #if XNU_TARGET_OS_OSX
1744 	if (vnode_is_rsr(imgp->ip_vp)) {
1745 		rsr_version = rsr_get_version();
1746 		os_atomic_or(&p->p_ladvflag, P_RSR, relaxed);
1747 		os_atomic_or(&p->p_vfs_iopolicy, P_VFS_IOPOLICY_ALTLINK, relaxed);
1748 	}
1749 #endif /* XNU_TARGET_OS_OSX */
1750 
1751 	error = vm_map_exec(map, task, load_result.is_64bit_addr,
1752 	    (void *)p->p_fd.fd_rdir, cputype, cpu_subtype, reslide,
1753 	    (imgp->ip_flags & IMGPF_DRIVER) != 0,
1754 	    rsr_version);
1755 
1756 	if (error) {
1757 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1758 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_MAP_EXEC_FAILURE, 0, 0);
1759 
1760 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MAP_EXEC_FAILURE);
1761 		if (bootarg_execfailurereports) {
1762 			set_proc_name(imgp, p);
1763 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1764 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1765 		}
1766 		/* release new address space since we won't use it */
1767 		imgp->ip_free_map = map;
1768 		map = VM_MAP_NULL;
1769 		goto badtoolate;
1770 	}
1771 
1772 	/*
1773 	 * Close file descriptors which specify close-on-exec.
1774 	 */
1775 	fdt_exec(p, vfs_context_ucred(imgp->ip_vfs_context),
1776 	    psa != NULL ? psa->psa_flags : 0, imgp->ip_new_thread, exec);
1777 
1778 	/*
1779 	 * deal with set[ug]id.
1780 	 */
1781 	error = exec_handle_sugid(imgp);
1782 	if (error) {
1783 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1784 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE, 0, 0);
1785 
1786 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE);
1787 		if (bootarg_execfailurereports) {
1788 			set_proc_name(imgp, p);
1789 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1790 		}
1791 
1792 		/* release new address space since we won't use it */
1793 		imgp->ip_free_map = map;
1794 		map = VM_MAP_NULL;
1795 		goto badtoolate;
1796 	}
1797 
1798 	/*
1799 	 * Commit to new map.
1800 	 *
1801 	 * Swap the new map for the old for target task, which consumes
1802 	 * our new map reference but each leaves us responsible for the
1803 	 * old_map reference.  That lets us get off the pmap associated
1804 	 * with it, and then we can release it.
1805 	 *
1806 	 * The map needs to be set on the target task which is different
1807 	 * than current task, thus swap_task_map is used instead of
1808 	 * vm_map_switch.
1809 	 */
1810 	old_map = swap_task_map(task, thread, map);
1811 #if MACH_ASSERT
1812 	/*
1813 	 * Reset the pmap's process info to prevent ledger checks
1814 	 * which might fail due to the ledgers being shared between
1815 	 * the old and new pmaps.
1816 	 */
1817 	vm_map_pmap_set_process(old_map, -1, "<old_map>");
1818 #endif /* MACH_ASSERT */
1819 	imgp->ip_free_map = old_map;
1820 	old_map = NULL;
1821 
1822 	lret = activate_exec_state(task, p, thread, &load_result);
1823 	if (lret != KERN_SUCCESS) {
1824 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1825 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE, 0, 0);
1826 
1827 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE);
1828 		if (bootarg_execfailurereports) {
1829 			set_proc_name(imgp, p);
1830 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1831 		}
1832 
1833 		goto badtoolate;
1834 	}
1835 
1836 	/*
1837 	 * deal with voucher on exec-calling thread.
1838 	 */
1839 	if (imgp->ip_new_thread == NULL) {
1840 		thread_set_mach_voucher(current_thread(), IPC_VOUCHER_NULL);
1841 	}
1842 
1843 	/* Make sure we won't interrupt ourself signalling a partial process */
1844 	if (!vfexec && !spawn && (p->p_lflag & P_LTRACED)) {
1845 		psignal(p, SIGTRAP);
1846 	}
1847 
1848 	if (load_result.unixproc &&
1849 	    create_unix_stack(get_task_map(task),
1850 	    &load_result,
1851 	    p) != KERN_SUCCESS) {
1852 		error = load_return_to_errno(LOAD_NOSPACE);
1853 
1854 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1855 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC, 0, 0);
1856 
1857 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC);
1858 		if (bootarg_execfailurereports) {
1859 			set_proc_name(imgp, p);
1860 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1861 		}
1862 
1863 		goto badtoolate;
1864 	}
1865 
1866 	/*
1867 	 * The load result will have already been munged by AMFI to include the
1868 	 * platform binary flag if boot-args dictated it (AMFI will mark anything
1869 	 * that doesn't go through the upcall path as a platform binary if its
1870 	 * enforcement is disabled).
1871 	 */
1872 	if (load_result.platform_binary) {
1873 		if (cs_debug) {
1874 			printf("setting platform binary on task: pid = %d\n", proc_getpid(p));
1875 		}
1876 
1877 		/*
1878 		 * We must use 'task' here because the proc's task has not yet been
1879 		 * switched to the new one.
1880 		 */
1881 		task_set_platform_binary(task, TRUE);
1882 	} else {
1883 		if (cs_debug) {
1884 			printf("clearing platform binary on task: pid = %d\n", proc_getpid(p));
1885 		}
1886 
1887 		task_set_platform_binary(task, FALSE);
1888 	}
1889 
1890 #if XNU_TARGET_OS_OSX
1891 	/* Disable mach hardening for all 1P tasks which load 3P plugins */
1892 	if (imgp->ip_flags & IMGPF_3P_PLUGINS) {
1893 		if (cs_debug) {
1894 			printf("Disabling some mach hardening on task due to 3P plugins: pid = %d\n", proc_getpid(p));
1895 		}
1896 		task_disable_mach_hardening(task);
1897 	}
1898 #if DEVELOPMENT || DEBUG
1899 	/* Disable mach hardening for all tasks if amfi_get_out_of_my_way is set.
1900 	 * Customers will have to turn SIP off to use this boot-arg, and so this is
1901 	 * only needed internally since we disable this feature when SIP is off. */
1902 	if (AMFI_bootarg_disable_mach_hardening) {
1903 		if (cs_debug) {
1904 			printf("Disabling some mach hardening on task due to AMFI boot-args: pid = %d\n", proc_getpid(p));
1905 		}
1906 		task_disable_mach_hardening(task);
1907 	}
1908 #endif /* DEVELOPMENT || DEBUG */
1909 #endif /* XNU_TARGET_OS_OSX */
1910 
1911 	error = exec_add_apple_strings(imgp, &load_result, task);     /* copies out main thread port */
1912 
1913 	if (error) {
1914 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1915 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT, 0, 0);
1916 
1917 		exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT);
1918 		if (bootarg_execfailurereports) {
1919 			set_proc_name(imgp, p);
1920 			exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1921 		}
1922 		goto badtoolate;
1923 	}
1924 
1925 	/* Switch to target task's map to copy out strings */
1926 	switch_ctx = vm_map_switch_to(get_task_map(task));
1927 
1928 	if (load_result.unixproc) {
1929 		user_addr_t     ap;
1930 
1931 		/*
1932 		 * Copy the strings area out into the new process address
1933 		 * space.
1934 		 */
1935 		ap = p->user_stack;
1936 		error = exec_copyout_strings(imgp, &ap);
1937 		if (error) {
1938 			vm_map_switch_back(switch_ctx);
1939 
1940 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1941 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS, 0, 0);
1942 
1943 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS);
1944 			if (bootarg_execfailurereports) {
1945 				set_proc_name(imgp, p);
1946 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1947 			}
1948 			goto badtoolate;
1949 		}
1950 		/* Set the stack */
1951 		thread_setuserstack(thread, ap);
1952 	}
1953 
1954 	if (load_result.dynlinker || load_result.is_rosetta) {
1955 		user_addr_t        ap;
1956 		int                     new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
1957 
1958 		/* Adjust the stack */
1959 		ap = thread_adjuserstack(thread, -new_ptr_size);
1960 		error = copyoutptr(load_result.mach_header, ap, new_ptr_size);
1961 
1962 		if (error) {
1963 			vm_map_switch_back(switch_ctx);
1964 
1965 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1966 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER, 0, 0);
1967 
1968 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER);
1969 			if (bootarg_execfailurereports) {
1970 				set_proc_name(imgp, p);
1971 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1972 			}
1973 			goto badtoolate;
1974 		}
1975 		error = task_set_dyld_info(task, load_result.all_image_info_addr,
1976 		    load_result.all_image_info_size, false);
1977 		if (error) {
1978 			vm_map_switch_back(switch_ctx);
1979 
1980 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1981 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO, 0, 0);
1982 
1983 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO);
1984 			if (bootarg_execfailurereports) {
1985 				set_proc_name(imgp, p);
1986 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1987 			}
1988 			error = EINVAL;
1989 			goto badtoolate;
1990 		}
1991 	} else {
1992 		/*
1993 		 * No dyld or rosetta loaded, set the TF_DYLD_ALL_IMAGE_FINAL bit on task.
1994 		 */
1995 		error = task_set_dyld_info(task, MACH_VM_MIN_ADDRESS,
1996 		    0, true);
1997 		if (error) {
1998 			vm_map_switch_back(switch_ctx);
1999 
2000 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
2001 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO, 0, 0);
2002 
2003 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO);
2004 			if (bootarg_execfailurereports) {
2005 				set_proc_name(imgp, p);
2006 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
2007 			}
2008 			error = EINVAL;
2009 			goto badtoolate;
2010 		}
2011 	}
2012 
2013 #if CONFIG_ROSETTA
2014 	if (load_result.is_rosetta) {
2015 		// Add an fd for the executable file for Rosetta's use
2016 		int main_binary_fd;
2017 		struct fileproc *fp;
2018 
2019 		error = falloc_exec(p, imgp->ip_vfs_context, &fp, &main_binary_fd);
2020 		if (error) {
2021 			vm_map_switch_back(switch_ctx);
2022 
2023 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
2024 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC, 0, 0);
2025 
2026 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC);
2027 			if (bootarg_execfailurereports) {
2028 				set_proc_name(imgp, p);
2029 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
2030 			}
2031 			goto badtoolate;
2032 		}
2033 
2034 		error = VNOP_OPEN(imgp->ip_vp, FREAD, imgp->ip_vfs_context);
2035 		if (error) {
2036 			vm_map_switch_back(switch_ctx);
2037 
2038 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
2039 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC, 0, 0);
2040 
2041 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC);
2042 			if (bootarg_execfailurereports) {
2043 				set_proc_name(imgp, p);
2044 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
2045 			}
2046 			goto cleanup_rosetta_fp;
2047 		}
2048 
2049 		fp->fp_glob->fg_flag = FREAD;
2050 		fp->fp_glob->fg_ops = &vnops;
2051 		fp_set_data(fp, imgp->ip_vp);
2052 
2053 		proc_fdlock(p);
2054 		procfdtbl_releasefd(p, main_binary_fd, NULL);
2055 		fp_drop(p, main_binary_fd, fp, 1);
2056 		proc_fdunlock(p);
2057 
2058 		vnode_ref(imgp->ip_vp);
2059 
2060 		// Pass the dyld load address, main binary fd, and dyld fd on the stack
2061 		uint64_t ap = thread_adjuserstack(thread, -24);
2062 
2063 		error = copyoutptr((user_addr_t)load_result.dynlinker_fd, ap, 8);
2064 		if (error) {
2065 			vm_map_switch_back(switch_ctx);
2066 
2067 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
2068 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
2069 
2070 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
2071 			if (bootarg_execfailurereports) {
2072 				set_proc_name(imgp, p);
2073 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
2074 			}
2075 			goto cleanup_rosetta_fp;
2076 		}
2077 
2078 		error = copyoutptr(load_result.dynlinker_mach_header, ap + 8, 8);
2079 		if (error) {
2080 			vm_map_switch_back(switch_ctx);
2081 
2082 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
2083 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
2084 
2085 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
2086 			if (bootarg_execfailurereports) {
2087 				set_proc_name(imgp, p);
2088 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
2089 			}
2090 			goto cleanup_rosetta_fp;
2091 		}
2092 
2093 		error = copyoutptr((user_addr_t)main_binary_fd, ap + 16, 8);
2094 		if (error) {
2095 			vm_map_switch_back(switch_ctx);
2096 
2097 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
2098 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
2099 
2100 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
2101 			if (bootarg_execfailurereports) {
2102 				set_proc_name(imgp, p);
2103 				exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
2104 			}
2105 			goto cleanup_rosetta_fp;
2106 		}
2107 
2108 cleanup_rosetta_fp:
2109 		if (error) {
2110 			fp_free(p, load_result.dynlinker_fd, load_result.dynlinker_fp);
2111 			fp_free(p, main_binary_fd, fp);
2112 			goto badtoolate;
2113 		}
2114 	}
2115 
2116 #endif
2117 
2118 	/* Avoid immediate VM faults back into kernel */
2119 	exec_prefault_data(p, imgp, &load_result);
2120 
2121 	vm_map_switch_back(switch_ctx);
2122 
2123 	/*
2124 	 * Reset signal state.
2125 	 */
2126 	execsigs(p, thread);
2127 
2128 	/*
2129 	 * need to cancel async IO requests that can be cancelled and wait for those
2130 	 * already active.  MAY BLOCK!
2131 	 */
2132 	_aio_exec( p );
2133 
2134 #if SYSV_SHM
2135 	/* FIXME: Till vmspace inherit is fixed: */
2136 	if (!vfexec && p->vm_shm) {
2137 		shmexec(p);
2138 	}
2139 #endif
2140 #if SYSV_SEM
2141 	/* Clean up the semaphores */
2142 	semexit(p);
2143 #endif
2144 
2145 	/*
2146 	 * Remember file name for accounting.
2147 	 */
2148 	p->p_acflag &= ~AFORK;
2149 
2150 	set_proc_name(imgp, p);
2151 
2152 #if CONFIG_SECLUDED_MEMORY
2153 	if (secluded_for_apps &&
2154 	    load_result.platform_binary) {
2155 		if (strncmp(p->p_name,
2156 		    "Camera",
2157 		    sizeof(p->p_name)) == 0) {
2158 			task_set_could_use_secluded_mem(task, TRUE);
2159 		} else {
2160 			task_set_could_use_secluded_mem(task, FALSE);
2161 		}
2162 		if (strncmp(p->p_name,
2163 		    "mediaserverd",
2164 		    sizeof(p->p_name)) == 0) {
2165 			task_set_could_also_use_secluded_mem(task, TRUE);
2166 		}
2167 		if (strncmp(p->p_name,
2168 		    "cameracaptured",
2169 		    sizeof(p->p_name)) == 0) {
2170 			task_set_could_also_use_secluded_mem(task, TRUE);
2171 		}
2172 	}
2173 #endif /* CONFIG_SECLUDED_MEMORY */
2174 
2175 #if __arm64__
2176 	if (load_result.legacy_footprint) {
2177 		task_set_legacy_footprint(task);
2178 	}
2179 #endif /* __arm64__ */
2180 
2181 	pal_dbg_set_task_name(task);
2182 
2183 #if DEVELOPMENT || DEBUG
2184 	/*
2185 	 * Update the pid an proc name for importance base if any
2186 	 */
2187 	task_importance_update_owner_info(task);
2188 #endif
2189 
2190 	proc_setexecutableuuid(p, &load_result.uuid[0]);
2191 
2192 #if CONFIG_DTRACE
2193 	dtrace_proc_exec(p);
2194 #endif
2195 
2196 	if (kdebug_enable) {
2197 		long args[4] = {};
2198 
2199 		uintptr_t fsid = 0, fileid = 0;
2200 		if (imgp->ip_vattr) {
2201 			uint64_t fsid64 = vnode_get_va_fsid(imgp->ip_vattr);
2202 			fsid   = (uintptr_t)fsid64;
2203 			fileid = (uintptr_t)imgp->ip_vattr->va_fileid;
2204 			// check for (unexpected) overflow and trace zero in that case
2205 			if (fsid != fsid64 || fileid != imgp->ip_vattr->va_fileid) {
2206 				fsid = fileid = 0;
2207 			}
2208 		}
2209 		KERNEL_DEBUG_CONSTANT_IST1(TRACE_DATA_EXEC, proc_getpid(p), fsid, fileid, 0,
2210 		    (uintptr_t)thread_tid(thread));
2211 
2212 		extern void kdebug_proc_name_args(struct proc *proc, long args[static 4]);
2213 		kdebug_proc_name_args(p, args);
2214 		KERNEL_DEBUG_CONSTANT_IST1(TRACE_STRING_EXEC, args[0], args[1],
2215 		    args[2], args[3], (uintptr_t)thread_tid(thread));
2216 	}
2217 
2218 
2219 	/*
2220 	 * If posix_spawned with the START_SUSPENDED flag, stop the
2221 	 * process before it runs.
2222 	 */
2223 	if (imgp->ip_px_sa != NULL) {
2224 		psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
2225 		if (psa->psa_flags & POSIX_SPAWN_START_SUSPENDED) {
2226 			proc_lock(p);
2227 			p->p_stat = SSTOP;
2228 			proc_unlock(p);
2229 			(void) task_suspend_internal(task);
2230 		}
2231 	}
2232 
2233 	/*
2234 	 * mark as execed
2235 	 */
2236 	OSBitOrAtomic(P_EXEC, &p->p_flag);
2237 	proc_resetregister(p);
2238 	if (p->p_pptr && (p->p_lflag & P_LPPWAIT)) {
2239 		proc_lock(p);
2240 		p->p_lflag &= ~P_LPPWAIT;
2241 		proc_unlock(p);
2242 		wakeup((caddr_t)p->p_pptr);
2243 	}
2244 
2245 	/*
2246 	 * Set up dext coredumps on kernel panic.
2247 	 * This requires the following:
2248 	 * - dext_panic_coredump=1 boot-arg (enabled by default on DEVELOPMENT, DEBUG and certain Seed builds)
2249 	 * - process must be a driver
2250 	 * - process must have the com.apple.private.enable-coredump-on-panic entitlement, and the
2251 	 *   entitlement has a string value.
2252 	 * - process must have the com.apple.private.enable-coredump-on-panic-seed-privacy-approved
2253 	 *   entitlement (Seed builds only).
2254 	 *
2255 	 * The core dump file name is formatted with the entitlement string value, followed by a hyphen
2256 	 * and the process PID.
2257 	 */
2258 	if (enable_dext_coredumps_on_panic &&
2259 	    (imgp->ip_flags & IMGPF_DRIVER) != 0 &&
2260 	    (userspace_coredump_name = IOVnodeGetEntitlement(imgp->ip_vp,
2261 	    (int64_t)imgp->ip_arch_offset, USERSPACE_COREDUMP_PANIC_ENTITLEMENT)) != NULL) {
2262 		size_t userspace_coredump_name_len = strlen(userspace_coredump_name);
2263 
2264 		char core_name[MACH_CORE_FILEHEADER_NAMELEN];
2265 		/* 16 - NULL char - strlen("-") - maximum of 5 digits for pid */
2266 		snprintf(core_name, MACH_CORE_FILEHEADER_NAMELEN, "%.9s-%d", userspace_coredump_name, proc_getpid(p));
2267 
2268 		kern_register_userspace_coredump(task, core_name);
2269 
2270 		/* Discard the copy of the entitlement */
2271 		kfree_data(userspace_coredump_name, userspace_coredump_name_len + 1);
2272 		userspace_coredump_name = NULL;
2273 	}
2274 
2275 	goto done;
2276 
2277 badtoolate:
2278 	/* Don't allow child process to execute any instructions */
2279 	if (!spawn) {
2280 		{
2281 			assert(exec_failure_reason != OS_REASON_NULL);
2282 			if (bootarg_execfailurereports) {
2283 				set_proc_name(imgp, current_proc());
2284 			}
2285 			psignal_with_reason(current_proc(), SIGKILL, exec_failure_reason);
2286 			exec_failure_reason = OS_REASON_NULL;
2287 
2288 			if (exec) {
2289 				/* Terminate the exec copy task */
2290 				task_terminate_internal(task);
2291 			}
2292 		}
2293 
2294 		/* We can't stop this system call at this point, so just pretend we succeeded */
2295 		error = 0;
2296 	} else {
2297 		os_reason_free(exec_failure_reason);
2298 		exec_failure_reason = OS_REASON_NULL;
2299 	}
2300 
2301 done:
2302 	if (load_result.threadstate) {
2303 		kfree_data(load_result.threadstate, load_result.threadstate_sz);
2304 		load_result.threadstate = NULL;
2305 	}
2306 
2307 bad:
2308 	/* If we hit this, we likely would have leaked an exit reason */
2309 	assert(exec_failure_reason == OS_REASON_NULL);
2310 	return error;
2311 }
2312 
2313 
2314 
2315 
2316 /*
2317  * Our image activator table; this is the table of the image types we are
2318  * capable of loading.  We list them in order of preference to ensure the
2319  * fastest image load speed.
2320  *
2321  * XXX hardcoded, for now; should use linker sets
2322  */
2323 struct execsw {
2324 	int(*const ex_imgact)(struct image_params *);
2325 	const char *ex_name;
2326 }const execsw[] = {
2327 	{ exec_mach_imgact, "Mach-o Binary" },
2328 	{ exec_fat_imgact, "Fat Binary" },
2329 	{ exec_shell_imgact, "Interpreter Script" },
2330 	{ NULL, NULL}
2331 };
2332 
2333 
2334 /*
2335  * exec_activate_image
2336  *
2337  * Description:	Iterate through the available image activators, and activate
2338  *		the image associated with the imgp structure.  We start with
2339  *		the activator for Mach-o binaries followed by that for Fat binaries
2340  *		for Interpreter scripts.
2341  *
2342  * Parameters:	struct image_params *	Image parameter block
2343  *
2344  * Returns:	0			Success
2345  *		ENOEXEC			No activator for image.
2346  *		EBADEXEC		The executable is corrupt/unknown
2347  *	execargs_alloc:EINVAL		Invalid argument
2348  *	execargs_alloc:EACCES		Permission denied
2349  *	execargs_alloc:EINTR		Interrupted function
2350  *	execargs_alloc:ENOMEM		Not enough space
2351  *	exec_save_path:EFAULT		Bad address
2352  *	exec_save_path:ENAMETOOLONG	Filename too long
2353  *	exec_check_permissions:EACCES	Permission denied
2354  *	exec_check_permissions:ENOEXEC	Executable file format error
2355  *	exec_check_permissions:ETXTBSY	Text file busy [misuse of error code]
2356  *	exec_check_permissions:???
2357  *	namei:???
2358  *	vn_rdwr:???			[anything vn_rdwr can return]
2359  *	<ex_imgact>:???			[anything an imgact can return]
2360  *	EDEADLK				Process is being terminated
2361  */
2362 static int
exec_activate_image(struct image_params * imgp)2363 exec_activate_image(struct image_params *imgp)
2364 {
2365 	struct nameidata *ndp = NULL;
2366 	const char *excpath;
2367 	int error;
2368 	int resid;
2369 	int once = 1;   /* save SGUID-ness for interpreted files */
2370 	int i;
2371 	int itercount = 0;
2372 	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2373 
2374 	/*
2375 	 * For exec, the translock needs to be taken on old proc and not
2376 	 * on new shadow proc.
2377 	 */
2378 	if (imgp->ip_flags & IMGPF_EXEC) {
2379 		p = current_proc();
2380 	}
2381 
2382 	error = execargs_alloc(imgp);
2383 	if (error) {
2384 		goto bad_notrans;
2385 	}
2386 
2387 	error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
2388 	if (error) {
2389 		goto bad_notrans;
2390 	}
2391 
2392 	/* Use excpath, which contains the copyin-ed exec path */
2393 	DTRACE_PROC1(exec, uintptr_t, excpath);
2394 
2395 	ndp = kalloc_type(struct nameidata, Z_WAITOK | Z_ZERO | Z_NOFAIL);
2396 
2397 	NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
2398 	    UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
2399 
2400 again:
2401 	error = namei(ndp);
2402 	if (error) {
2403 		if (error == ERESTART) {
2404 			error = EINTR;
2405 		}
2406 		goto bad_notrans;
2407 	}
2408 	imgp->ip_ndp = ndp;     /* successful namei(); call nameidone() later */
2409 	imgp->ip_vp = ndp->ni_vp;       /* if set, need to vnode_put() at some point */
2410 
2411 	/*
2412 	 * Before we start the transition from binary A to binary B, make
2413 	 * sure another thread hasn't started exiting the process.  We grab
2414 	 * the proc lock to check p_lflag initially, and the transition
2415 	 * mechanism ensures that the value doesn't change after we release
2416 	 * the lock.
2417 	 */
2418 	proc_lock(p);
2419 	if (p->p_lflag & P_LEXIT) {
2420 		error = EDEADLK;
2421 		proc_unlock(p);
2422 		goto bad_notrans;
2423 	}
2424 	error = proc_transstart(p, 1, 0);
2425 	proc_unlock(p);
2426 	if (error) {
2427 		goto bad_notrans;
2428 	}
2429 
2430 	error = exec_check_permissions(imgp);
2431 	if (error) {
2432 		goto bad;
2433 	}
2434 
2435 	/* Copy; avoid invocation of an interpreter overwriting the original */
2436 	if (once) {
2437 		once = 0;
2438 		*imgp->ip_origvattr = *imgp->ip_vattr;
2439 	}
2440 
2441 	error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata, PAGE_SIZE, 0,
2442 	    UIO_SYSSPACE, IO_NODELOCKED,
2443 	    vfs_context_ucred(imgp->ip_vfs_context),
2444 	    &resid, vfs_context_proc(imgp->ip_vfs_context));
2445 	if (error) {
2446 		goto bad;
2447 	}
2448 
2449 	if (resid) {
2450 		memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
2451 	}
2452 
2453 encapsulated_binary:
2454 	/* Limit the number of iterations we will attempt on each binary */
2455 	if (++itercount > EAI_ITERLIMIT) {
2456 		error = EBADEXEC;
2457 		goto bad;
2458 	}
2459 	error = -1;
2460 	for (i = 0; error == -1 && execsw[i].ex_imgact != NULL; i++) {
2461 		error = (*execsw[i].ex_imgact)(imgp);
2462 
2463 		switch (error) {
2464 		/* case -1: not claimed: continue */
2465 		case -2:                /* Encapsulated binary, imgp->ip_XXX set for next iteration */
2466 			goto encapsulated_binary;
2467 
2468 		case -3:                /* Interpreter */
2469 #if CONFIG_MACF
2470 			/*
2471 			 * Copy the script label for later use. Note that
2472 			 * the label can be different when the script is
2473 			 * actually read by the interpreter.
2474 			 */
2475 			if (imgp->ip_scriptlabelp) {
2476 				mac_vnode_label_free(imgp->ip_scriptlabelp);
2477 				imgp->ip_scriptlabelp = NULL;
2478 			}
2479 			imgp->ip_scriptlabelp = mac_vnode_label_alloc(NULL);
2480 			if (imgp->ip_scriptlabelp == NULL) {
2481 				error = ENOMEM;
2482 				break;
2483 			}
2484 			mac_vnode_label_copy(mac_vnode_label(imgp->ip_vp),
2485 			    imgp->ip_scriptlabelp);
2486 
2487 			/*
2488 			 * Take a ref of the script vnode for later use.
2489 			 */
2490 			if (imgp->ip_scriptvp) {
2491 				vnode_put(imgp->ip_scriptvp);
2492 				imgp->ip_scriptvp = NULLVP;
2493 			}
2494 			if (vnode_getwithref(imgp->ip_vp) == 0) {
2495 				imgp->ip_scriptvp = imgp->ip_vp;
2496 			}
2497 #endif
2498 
2499 			nameidone(ndp);
2500 
2501 			vnode_put(imgp->ip_vp);
2502 			imgp->ip_vp = NULL;     /* already put */
2503 			imgp->ip_ndp = NULL; /* already nameidone */
2504 
2505 			/* Use excpath, which exec_shell_imgact reset to the interpreter */
2506 			NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF,
2507 			    UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
2508 
2509 			proc_transend(p, 0);
2510 			goto again;
2511 
2512 		default:
2513 			break;
2514 		}
2515 	}
2516 
2517 	if (error == -1) {
2518 		error = ENOEXEC;
2519 	} else if (error == 0) {
2520 		if (imgp->ip_flags & IMGPF_INTERPRET && ndp->ni_vp) {
2521 			AUDIT_ARG(vnpath, ndp->ni_vp, ARG_VNODE2);
2522 		}
2523 
2524 		/*
2525 		 * Call out to allow 3rd party notification of exec.
2526 		 * Ignore result of kauth_authorize_fileop call.
2527 		 */
2528 		if (kauth_authorize_fileop_has_listeners()) {
2529 			kauth_authorize_fileop(vfs_context_ucred(imgp->ip_vfs_context),
2530 			    KAUTH_FILEOP_EXEC,
2531 			    (uintptr_t)ndp->ni_vp, 0);
2532 		}
2533 	}
2534 bad:
2535 	proc_transend(p, 0);
2536 
2537 bad_notrans:
2538 	if (imgp->ip_strings) {
2539 		execargs_free(imgp);
2540 	}
2541 	if (imgp->ip_ndp) {
2542 		nameidone(imgp->ip_ndp);
2543 	}
2544 	kfree_type(struct nameidata, ndp);
2545 
2546 	return error;
2547 }
2548 
2549 
2550 /*
2551  * exec_validate_spawnattr_policy
2552  *
2553  * Description: Validates the entitlements required to set the apptype.
2554  *
2555  * Parameters:  int psa_apptype         posix spawn attribute apptype
2556  *
2557  * Returns:     0                       Success
2558  *              EPERM                   Failure
2559  */
2560 static errno_t
exec_validate_spawnattr_policy(int psa_apptype)2561 exec_validate_spawnattr_policy(int psa_apptype)
2562 {
2563 	if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
2564 		int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
2565 		if (proctype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
2566 			if (!IOCurrentTaskHasEntitlement(POSIX_SPAWN_ENTITLEMENT_DRIVER)) {
2567 				return EPERM;
2568 			}
2569 		}
2570 	}
2571 
2572 	return 0;
2573 }
2574 
2575 /*
2576  * exec_handle_spawnattr_policy
2577  *
2578  * Description: Decode and apply the posix_spawn apptype, qos clamp, and watchport ports to the task.
2579  *
2580  * Parameters:  proc_t p                process to apply attributes to
2581  *              int psa_apptype         posix spawn attribute apptype
2582  *
2583  * Returns:     0                       Success
2584  */
2585 static errno_t
exec_handle_spawnattr_policy(proc_t p,thread_t thread,int psa_apptype,uint64_t psa_qos_clamp,task_role_t psa_darwin_role,struct exec_port_actions * port_actions)2586 exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
2587     task_role_t psa_darwin_role, struct exec_port_actions *port_actions)
2588 {
2589 	int apptype     = TASK_APPTYPE_NONE;
2590 	int qos_clamp   = THREAD_QOS_UNSPECIFIED;
2591 	task_role_t role = TASK_UNSPECIFIED;
2592 
2593 	if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
2594 		int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
2595 
2596 		switch (proctype) {
2597 		case POSIX_SPAWN_PROC_TYPE_DAEMON_INTERACTIVE:
2598 			apptype = TASK_APPTYPE_DAEMON_INTERACTIVE;
2599 			break;
2600 		case POSIX_SPAWN_PROC_TYPE_DAEMON_STANDARD:
2601 			apptype = TASK_APPTYPE_DAEMON_STANDARD;
2602 			break;
2603 		case POSIX_SPAWN_PROC_TYPE_DAEMON_ADAPTIVE:
2604 			apptype = TASK_APPTYPE_DAEMON_ADAPTIVE;
2605 			break;
2606 		case POSIX_SPAWN_PROC_TYPE_DAEMON_BACKGROUND:
2607 			apptype = TASK_APPTYPE_DAEMON_BACKGROUND;
2608 			break;
2609 		case POSIX_SPAWN_PROC_TYPE_APP_DEFAULT:
2610 			apptype = TASK_APPTYPE_APP_DEFAULT;
2611 			break;
2612 		case POSIX_SPAWN_PROC_TYPE_APP_NONUI:
2613 			apptype = TASK_APPTYPE_APP_NONUI;
2614 			break;
2615 		case POSIX_SPAWN_PROC_TYPE_DRIVER:
2616 			apptype = TASK_APPTYPE_DRIVER;
2617 			break;
2618 		default:
2619 			apptype = TASK_APPTYPE_NONE;
2620 			/* TODO: Should an invalid value here fail the spawn? */
2621 			break;
2622 		}
2623 	}
2624 
2625 	if (psa_qos_clamp != POSIX_SPAWN_PROC_CLAMP_NONE) {
2626 		switch (psa_qos_clamp) {
2627 		case POSIX_SPAWN_PROC_CLAMP_UTILITY:
2628 			qos_clamp = THREAD_QOS_UTILITY;
2629 			break;
2630 		case POSIX_SPAWN_PROC_CLAMP_BACKGROUND:
2631 			qos_clamp = THREAD_QOS_BACKGROUND;
2632 			break;
2633 		case POSIX_SPAWN_PROC_CLAMP_MAINTENANCE:
2634 			qos_clamp = THREAD_QOS_MAINTENANCE;
2635 			break;
2636 		default:
2637 			qos_clamp = THREAD_QOS_UNSPECIFIED;
2638 			/* TODO: Should an invalid value here fail the spawn? */
2639 			break;
2640 		}
2641 	}
2642 
2643 	if (psa_darwin_role != PRIO_DARWIN_ROLE_DEFAULT) {
2644 		proc_darwin_role_to_task_role(psa_darwin_role, &role);
2645 	}
2646 
2647 	if (apptype != TASK_APPTYPE_NONE ||
2648 	    qos_clamp != THREAD_QOS_UNSPECIFIED ||
2649 	    role != TASK_UNSPECIFIED ||
2650 	    port_actions->portwatch_count) {
2651 		proc_set_task_spawnpolicy(proc_task(p), thread, apptype, qos_clamp, role,
2652 		    port_actions->portwatch_array, port_actions->portwatch_count);
2653 	}
2654 
2655 	if (port_actions->registered_count) {
2656 		if (_kernelrpc_mach_ports_register3(proc_task(p),
2657 		    port_actions->registered_array[0],
2658 		    port_actions->registered_array[1],
2659 		    port_actions->registered_array[2])) {
2660 			return EINVAL;
2661 		}
2662 		/* mach_ports_register() consumed the array */
2663 		bzero(port_actions->registered_array,
2664 		    sizeof(port_actions->registered_array));
2665 		port_actions->registered_count = 0;
2666 	}
2667 
2668 	return 0;
2669 }
2670 
2671 static void
exec_port_actions_destroy(struct exec_port_actions * port_actions)2672 exec_port_actions_destroy(struct exec_port_actions *port_actions)
2673 {
2674 	if (port_actions->excport_array) {
2675 		for (uint32_t i = 0; i < port_actions->exception_port_count; i++) {
2676 			ipc_port_t port = NULL;
2677 			if ((port = port_actions->excport_array[i].port) != NULL) {
2678 				ipc_port_release_send(port);
2679 			}
2680 		}
2681 		kfree_type(struct exception_port_action_t, port_actions->exception_port_count,
2682 		    port_actions->excport_array);
2683 	}
2684 
2685 	if (port_actions->portwatch_array) {
2686 		for (uint32_t i = 0; i < port_actions->portwatch_count; i++) {
2687 			ipc_port_t port = NULL;
2688 			if ((port = port_actions->portwatch_array[i]) != NULL) {
2689 				ipc_port_release_send(port);
2690 			}
2691 		}
2692 		kfree_type(ipc_port_t, port_actions->portwatch_count,
2693 		    port_actions->portwatch_array);
2694 	}
2695 
2696 	for (uint32_t i = 0; i < port_actions->registered_count; i++) {
2697 		ipc_port_t port = NULL;
2698 		if ((port = port_actions->registered_array[i]) != NULL) {
2699 			ipc_port_release_send(port);
2700 		}
2701 	}
2702 }
2703 
2704 /*
2705  * exec_handle_port_actions
2706  *
2707  * Description:	Go through the _posix_port_actions_t contents,
2708  *              calling task_set_special_port, task_set_exception_ports
2709  *              and/or audit_session_spawnjoin for the current task.
2710  *
2711  * Parameters:	struct image_params *	Image parameter block
2712  *
2713  * Returns:	0			Success
2714  *              EINVAL			Failure
2715  *              ENOTSUP			Illegal posix_spawn attr flag was set
2716  */
2717 static errno_t
exec_handle_port_actions(struct image_params * imgp,struct exec_port_actions * actions)2718 exec_handle_port_actions(struct image_params *imgp,
2719     struct exec_port_actions *actions)
2720 {
2721 	_posix_spawn_port_actions_t pacts = imgp->ip_px_spa;
2722 #if CONFIG_AUDIT
2723 	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2724 #endif
2725 	_ps_port_action_t *act = NULL;
2726 	task_t task = get_threadtask(imgp->ip_new_thread);
2727 	ipc_port_t port = NULL;
2728 	errno_t ret = 0;
2729 	int i = 0, portwatch_i = 0, registered_i = 0, excport_i = 0;
2730 	kern_return_t kr;
2731 	boolean_t task_has_watchport_boost = task_has_watchports(current_task());
2732 	boolean_t in_exec = (imgp->ip_flags & IMGPF_EXEC);
2733 	int ptrauth_task_port_count = 0;
2734 
2735 	for (i = 0; i < pacts->pspa_count; i++) {
2736 		act = &pacts->pspa_actions[i];
2737 
2738 		switch (act->port_type) {
2739 		case PSPA_SPECIAL:
2740 #if CONFIG_AUDIT
2741 		case PSPA_AU_SESSION:
2742 #endif
2743 			break;
2744 		case PSPA_EXCEPTION:
2745 			if (++actions->exception_port_count > TASK_MAX_EXCEPTION_PORT_COUNT) {
2746 				ret = EINVAL;
2747 				goto done;
2748 			}
2749 			break;
2750 		case PSPA_IMP_WATCHPORTS:
2751 			if (++actions->portwatch_count > TASK_MAX_WATCHPORT_COUNT) {
2752 				ret = EINVAL;
2753 				goto done;
2754 			}
2755 			break;
2756 		case PSPA_REGISTERED_PORTS:
2757 			if (++actions->registered_count > TASK_PORT_REGISTER_MAX) {
2758 				ret = EINVAL;
2759 				goto done;
2760 			}
2761 			break;
2762 		case PSPA_PTRAUTH_TASK_PORT:
2763 			if (++ptrauth_task_port_count > 1) {
2764 				ret = EINVAL;
2765 				goto done;
2766 			}
2767 			break;
2768 		default:
2769 			ret = EINVAL;
2770 			goto done;
2771 		}
2772 	}
2773 
2774 	if (actions->exception_port_count) {
2775 		actions->excport_array = kalloc_type(struct exception_port_action_t,
2776 		    actions->exception_port_count, Z_WAITOK | Z_ZERO);
2777 
2778 		if (actions->excport_array == NULL) {
2779 			ret = ENOMEM;
2780 			goto done;
2781 		}
2782 	}
2783 	if (actions->portwatch_count) {
2784 		if (in_exec && task_has_watchport_boost) {
2785 			ret = EINVAL;
2786 			goto done;
2787 		}
2788 		actions->portwatch_array = kalloc_type(ipc_port_t,
2789 		    actions->portwatch_count, Z_WAITOK | Z_ZERO);
2790 		if (actions->portwatch_array == NULL) {
2791 			ret = ENOMEM;
2792 			goto done;
2793 		}
2794 	}
2795 
2796 	for (i = 0; i < pacts->pspa_count; i++) {
2797 		act = &pacts->pspa_actions[i];
2798 
2799 		if (MACH_PORT_VALID(act->new_port)) {
2800 			kr = ipc_typed_port_copyin_send(get_task_ipcspace(current_task()),
2801 			    act->new_port, IOT_ANY, &port);
2802 
2803 			if (kr != KERN_SUCCESS) {
2804 				ret = EINVAL;
2805 				goto done;
2806 			}
2807 		} else {
2808 			/* it's NULL or DEAD */
2809 			port = CAST_MACH_NAME_TO_PORT(act->new_port);
2810 		}
2811 
2812 		switch (act->port_type) {
2813 		case PSPA_SPECIAL:
2814 			kr = task_set_special_port(task, act->which, port);
2815 
2816 			if (kr != KERN_SUCCESS) {
2817 				ret = EINVAL;
2818 			}
2819 			break;
2820 
2821 #if CONFIG_AUDIT
2822 		case PSPA_AU_SESSION:
2823 			ret = audit_session_spawnjoin(p, port);
2824 			if (ret) {
2825 				/* audit_session_spawnjoin() has already dropped the reference in case of error. */
2826 				goto done;
2827 			}
2828 
2829 			break;
2830 #endif
2831 		case PSPA_EXCEPTION:
2832 			assert(excport_i < actions->exception_port_count);
2833 			/* hold on to this till end of spawn */
2834 			actions->excport_array[excport_i].port_action = act;
2835 			actions->excport_array[excport_i].port = port;
2836 			excport_i++;
2837 			break;
2838 		case PSPA_IMP_WATCHPORTS:
2839 			assert(portwatch_i < actions->portwatch_count);
2840 			/* hold on to this till end of spawn */
2841 			actions->portwatch_array[portwatch_i++] = port;
2842 			break;
2843 		case PSPA_REGISTERED_PORTS:
2844 			assert(registered_i < actions->registered_count);
2845 			/* hold on to this till end of spawn */
2846 			actions->registered_array[registered_i++] = port;
2847 			break;
2848 
2849 		case PSPA_PTRAUTH_TASK_PORT:
2850 #if (DEVELOPMENT || DEBUG)
2851 #if defined(HAS_APPLE_PAC)
2852 			{
2853 				task_t ptr_auth_task = convert_port_to_task(port);
2854 
2855 				if (ptr_auth_task == TASK_NULL) {
2856 					ret = EINVAL;
2857 					break;
2858 				}
2859 
2860 				imgp->ip_inherited_shared_region_id =
2861 				    task_get_vm_shared_region_id_and_jop_pid(ptr_auth_task,
2862 				    &imgp->ip_inherited_jop_pid);
2863 
2864 				/* Deallocate task ref returned by convert_port_to_task */
2865 				task_deallocate(ptr_auth_task);
2866 			}
2867 #endif /* HAS_APPLE_PAC */
2868 #endif /* (DEVELOPMENT || DEBUG) */
2869 
2870 			/* consume the port right in case of success */
2871 			ipc_port_release_send(port);
2872 			break;
2873 		default:
2874 			ret = EINVAL;
2875 			break;
2876 		}
2877 
2878 		if (ret) {
2879 			/* action failed, so release port resources */
2880 			ipc_port_release_send(port);
2881 			break;
2882 		}
2883 	}
2884 
2885 done:
2886 	if (0 != ret) {
2887 		DTRACE_PROC1(spawn__port__failure, mach_port_name_t, act->new_port);
2888 	}
2889 	return ret;
2890 }
2891 
2892 
2893 /*
2894  * exec_handle_exception_port_actions
2895  *
2896  * Description:	Go through the saved exception ports in exec_port_actions,
2897  *              calling task_set_exception_ports for the current Task.
2898  *              This must happen after image activation, and after exec_resettextvp()
2899  *				because task_set_exception_ports checks the `TF_PLATFORM` bit and entitlements.
2900  *
2901  * Parameters:	struct image_params *		Image parameter block
2902  *                              struct exec_port_actions *  Saved Port Actions
2903  *
2904  * Returns:	0			Success
2905  *              EINVAL			task_set_exception_ports failed
2906  */
2907 static errno_t
exec_handle_exception_port_actions(const struct image_params * imgp,const struct exec_port_actions * actions)2908 exec_handle_exception_port_actions(const struct image_params *imgp,
2909     const struct exec_port_actions *actions)
2910 {
2911 	task_t task = get_threadtask(imgp->ip_new_thread);
2912 
2913 	for (int i = 0; i < actions->exception_port_count; i++) {
2914 		ipc_port_t port = actions->excport_array[i].port;
2915 		_ps_port_action_t *act = actions->excport_array[i].port_action;
2916 		assert(act != NULL);
2917 		kern_return_t kr = task_set_exception_ports(task, act->mask, port,
2918 		    act->behavior, act->flavor);
2919 		if (kr != KERN_SUCCESS) {
2920 			DTRACE_PROC1(spawn__exception__port__failure, mach_port_name_t, act->new_port);
2921 			return EINVAL;
2922 		}
2923 		actions->excport_array[i].port = NULL;
2924 	}
2925 
2926 	return 0;
2927 }
2928 
2929 
2930 /*
2931  * exec_handle_file_actions
2932  *
2933  * Description:	Go through the _posix_file_actions_t contents applying the
2934  *		open, close, and dup2 operations to the open file table for
2935  *		the current process.
2936  *
2937  * Parameters:	struct image_params *	Image parameter block
2938  *
2939  * Returns:	0			Success
2940  *		???
2941  *
2942  * Note:	Actions are applied in the order specified, with the credential
2943  *		of the parent process.  This is done to permit the parent
2944  *		process to utilize POSIX_SPAWN_RESETIDS to drop privilege in
2945  *		the child following operations the child may in fact not be
2946  *		normally permitted to perform.
2947  */
2948 static int
exec_handle_file_actions(struct image_params * imgp,short psa_flags)2949 exec_handle_file_actions(struct image_params *imgp, short psa_flags)
2950 {
2951 	int error = 0;
2952 	int action;
2953 	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2954 	kauth_cred_t p_cred = vfs_context_ucred(imgp->ip_vfs_context);
2955 	_posix_spawn_file_actions_t px_sfap = imgp->ip_px_sfa;
2956 	int ival[2];            /* dummy retval for system calls) */
2957 #if CONFIG_AUDIT
2958 	struct uthread *uthread = current_uthread();
2959 #endif
2960 
2961 	for (action = 0; action < px_sfap->psfa_act_count; action++) {
2962 		_psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
2963 
2964 		switch (psfa->psfaa_type) {
2965 		case PSFA_OPEN: {
2966 			/*
2967 			 * Open is different, in that it requires the use of
2968 			 * a path argument, which is normally copied in from
2969 			 * user space; because of this, we have to support an
2970 			 * open from kernel space that passes an address space
2971 			 * context of UIO_SYSSPACE, and casts the address
2972 			 * argument to a user_addr_t.
2973 			 */
2974 			struct vnode_attr *vap;
2975 			struct nameidata *ndp;
2976 			int mode = psfa->psfaa_openargs.psfao_mode;
2977 			int origfd;
2978 			struct {
2979 				struct vnode_attr va;
2980 				struct nameidata nd;
2981 			} *__open_data;
2982 
2983 			__open_data = kalloc_type(typeof(*__open_data), Z_WAITOK | Z_ZERO);
2984 			if (__open_data == NULL) {
2985 				error = ENOMEM;
2986 				break;
2987 			}
2988 
2989 			vap = &__open_data->va;
2990 			ndp = &__open_data->nd;
2991 
2992 			VATTR_INIT(vap);
2993 			/* Mask off all but regular access permissions */
2994 			mode = ((mode & ~p->p_fd.fd_cmask) & ALLPERMS) & ~S_ISTXT;
2995 			VATTR_SET(vap, va_mode, mode & ACCESSPERMS);
2996 
2997 			AUDIT_SUBCALL_ENTER(OPEN, p, uthread);
2998 
2999 			NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
3000 			    CAST_USER_ADDR_T(psfa->psfaa_openargs.psfao_path),
3001 			    imgp->ip_vfs_context);
3002 
3003 			error = open1(imgp->ip_vfs_context, ndp,
3004 			    psfa->psfaa_openargs.psfao_oflag,
3005 			    vap, NULL, NULL, &origfd, AUTH_OPEN_NOAUTHFD);
3006 
3007 			kfree_type(typeof(*__open_data), __open_data);
3008 
3009 			AUDIT_SUBCALL_EXIT(uthread, error);
3010 
3011 			/*
3012 			 * If there's an error, or we get the right fd by
3013 			 * accident, then drop out here.  This is easier than
3014 			 * reworking all the open code to preallocate fd
3015 			 * slots, and internally taking one as an argument.
3016 			 */
3017 			if (error || origfd == psfa->psfaa_filedes) {
3018 				break;
3019 			}
3020 
3021 			/*
3022 			 * If we didn't fall out from an error, we ended up
3023 			 * with the wrong fd; so now we've got to try to dup2
3024 			 * it to the right one.
3025 			 */
3026 			AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
3027 			error = dup2(p, p_cred, origfd, psfa->psfaa_filedes, ival);
3028 			AUDIT_SUBCALL_EXIT(uthread, error);
3029 			if (error) {
3030 				break;
3031 			}
3032 
3033 			/*
3034 			 * Finally, close the original fd.
3035 			 */
3036 			AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
3037 			error = close_nocancel(p, p_cred, origfd);
3038 			AUDIT_SUBCALL_EXIT(uthread, error);
3039 		}
3040 		break;
3041 
3042 		case PSFA_DUP2: {
3043 			AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
3044 			error = dup2(p, p_cred, psfa->psfaa_filedes,
3045 			    psfa->psfaa_dup2args.psfad_newfiledes, ival);
3046 			AUDIT_SUBCALL_EXIT(uthread, error);
3047 		}
3048 		break;
3049 
3050 		case PSFA_FILEPORT_DUP2: {
3051 			ipc_port_t port;
3052 			kern_return_t kr;
3053 			int origfd;
3054 
3055 			if (!MACH_PORT_VALID(psfa->psfaa_fileport)) {
3056 				error = EINVAL;
3057 				break;
3058 			}
3059 
3060 			kr = ipc_typed_port_copyin_send(get_task_ipcspace(current_task()),
3061 			    psfa->psfaa_fileport, IKOT_FILEPORT, &port);
3062 
3063 			if (kr != KERN_SUCCESS) {
3064 				error = EINVAL;
3065 				break;
3066 			}
3067 
3068 			error = fileport_makefd(p, port, 0, &origfd);
3069 
3070 			if (IPC_PORT_NULL != port) {
3071 				ipc_typed_port_release_send(port, IKOT_FILEPORT);
3072 			}
3073 
3074 			if (error || origfd == psfa->psfaa_dup2args.psfad_newfiledes) {
3075 				break;
3076 			}
3077 
3078 			AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
3079 			error = dup2(p, p_cred, origfd,
3080 			    psfa->psfaa_dup2args.psfad_newfiledes, ival);
3081 			AUDIT_SUBCALL_EXIT(uthread, error);
3082 			if (error) {
3083 				break;
3084 			}
3085 
3086 			AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
3087 			error = close_nocancel(p, p_cred, origfd);
3088 			AUDIT_SUBCALL_EXIT(uthread, error);
3089 		}
3090 		break;
3091 
3092 		case PSFA_CLOSE: {
3093 			AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
3094 			error = close_nocancel(p, p_cred, psfa->psfaa_filedes);
3095 			AUDIT_SUBCALL_EXIT(uthread, error);
3096 		}
3097 		break;
3098 
3099 		case PSFA_INHERIT: {
3100 			struct fileproc *fp;
3101 
3102 			/*
3103 			 * Check to see if the descriptor exists, and
3104 			 * ensure it's -not- marked as close-on-exec.
3105 			 *
3106 			 * Attempting to "inherit" a guarded fd will
3107 			 * result in a error.
3108 			 */
3109 
3110 			proc_fdlock(p);
3111 			if ((fp = fp_get_noref_locked(p, psfa->psfaa_filedes)) == NULL) {
3112 				error = EBADF;
3113 			} else if (fp->fp_guard_attrs) {
3114 				error = fp_guard_exception(p, psfa->psfaa_filedes,
3115 				    fp, kGUARD_EXC_NOCLOEXEC);
3116 			} else {
3117 				fp->fp_flags &= ~FP_CLOEXEC;
3118 				error = 0;
3119 			}
3120 			proc_fdunlock(p);
3121 		}
3122 		break;
3123 
3124 		case PSFA_CHDIR: {
3125 			/*
3126 			 * Chdir is different, in that it requires the use of
3127 			 * a path argument, which is normally copied in from
3128 			 * user space; because of this, we have to support a
3129 			 * chdir from kernel space that passes an address space
3130 			 * context of UIO_SYSSPACE, and casts the address
3131 			 * argument to a user_addr_t.
3132 			 */
3133 			struct nameidata *nd;
3134 			nd = kalloc_type(struct nameidata,
3135 			    Z_WAITOK | Z_ZERO | Z_NOFAIL);
3136 
3137 			AUDIT_SUBCALL_ENTER(CHDIR, p, uthread);
3138 			NDINIT(nd, LOOKUP, OP_CHDIR, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
3139 			    CAST_USER_ADDR_T(psfa->psfaa_chdirargs.psfac_path),
3140 			    imgp->ip_vfs_context);
3141 
3142 			error = chdir_internal(p, imgp->ip_vfs_context, nd, 0);
3143 			kfree_type(struct nameidata, nd);
3144 			AUDIT_SUBCALL_EXIT(uthread, error);
3145 		}
3146 		break;
3147 
3148 		case PSFA_FCHDIR: {
3149 			AUDIT_SUBCALL_ENTER(FCHDIR, p, uthread);
3150 			error = fchdir(p, imgp->ip_vfs_context,
3151 			    psfa->psfaa_filedes, false);
3152 			AUDIT_SUBCALL_EXIT(uthread, error);
3153 		}
3154 		break;
3155 
3156 		default:
3157 			error = EINVAL;
3158 			break;
3159 		}
3160 
3161 		/* All file actions failures are considered fatal, per POSIX */
3162 
3163 		if (error) {
3164 			if (PSFA_OPEN == psfa->psfaa_type) {
3165 				DTRACE_PROC1(spawn__open__failure, uintptr_t,
3166 				    psfa->psfaa_openargs.psfao_path);
3167 			} else {
3168 				DTRACE_PROC1(spawn__fd__failure, int, psfa->psfaa_filedes);
3169 			}
3170 			break;
3171 		}
3172 	}
3173 
3174 	if (error != 0 || (psa_flags & POSIX_SPAWN_CLOEXEC_DEFAULT) == 0) {
3175 		return error;
3176 	}
3177 
3178 	/*
3179 	 * If POSIX_SPAWN_CLOEXEC_DEFAULT is set, behave (during
3180 	 * this spawn only) as if "close on exec" is the default
3181 	 * disposition of all pre-existing file descriptors.  In this case,
3182 	 * the list of file descriptors mentioned in the file actions
3183 	 * are the only ones that can be inherited, so mark them now.
3184 	 *
3185 	 * The actual closing part comes later, in fdt_exec().
3186 	 */
3187 	proc_fdlock(p);
3188 	for (action = 0; action < px_sfap->psfa_act_count; action++) {
3189 		_psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
3190 		int fd = psfa->psfaa_filedes;
3191 
3192 		switch (psfa->psfaa_type) {
3193 		case PSFA_DUP2:
3194 		case PSFA_FILEPORT_DUP2:
3195 			fd = psfa->psfaa_dup2args.psfad_newfiledes;
3196 			OS_FALLTHROUGH;
3197 		case PSFA_OPEN:
3198 		case PSFA_INHERIT:
3199 			*fdflags(p, fd) |= UF_INHERIT;
3200 			break;
3201 
3202 		case PSFA_CLOSE:
3203 		case PSFA_CHDIR:
3204 		case PSFA_FCHDIR:
3205 			/*
3206 			 * Although PSFA_FCHDIR does have a file descriptor, it is not
3207 			 * *creating* one, thus we do not automatically mark it for
3208 			 * inheritance under POSIX_SPAWN_CLOEXEC_DEFAULT. A client that
3209 			 * wishes it to be inherited should use the PSFA_INHERIT action
3210 			 * explicitly.
3211 			 */
3212 			break;
3213 		}
3214 	}
3215 	proc_fdunlock(p);
3216 
3217 	return 0;
3218 }
3219 
3220 #if CONFIG_MACF
3221 /*
3222  * Check that the extension's data is within the bounds of the
3223  * allocation storing all extensions' data
3224  */
3225 static inline errno_t
exec_spawnattr_validate_policyext_data(const struct ip_px_smpx_s * px_s,const _ps_mac_policy_extension_t * ext)3226 exec_spawnattr_validate_policyext_data(const struct ip_px_smpx_s *px_s,
3227     const _ps_mac_policy_extension_t *ext)
3228 {
3229 	uint64_t dataend;
3230 
3231 	if (__improbable(os_add_overflow(ext->dataoff, ext->datalen, &dataend))) {
3232 		return EOVERFLOW;
3233 	}
3234 	if (__improbable(dataend > px_s->datalen)) {
3235 		return EINVAL;
3236 	}
3237 
3238 	return 0;
3239 }
3240 
3241 /*
3242  * exec_spawnattr_getmacpolicyinfo
3243  */
3244 void *
exec_spawnattr_getmacpolicyinfo(const void * macextensions,const char * policyname,size_t * lenp)3245 exec_spawnattr_getmacpolicyinfo(const void *macextensions, const char *policyname, size_t *lenp)
3246 {
3247 	const struct ip_px_smpx_s *px_s = macextensions;
3248 	const struct _posix_spawn_mac_policy_extensions *psmx = NULL;
3249 	int i;
3250 
3251 	if (px_s == NULL) {
3252 		return NULL;
3253 	}
3254 
3255 	psmx = px_s->array;
3256 	if (psmx == NULL) {
3257 		return NULL;
3258 	}
3259 
3260 	for (i = 0; i < psmx->psmx_count; i++) {
3261 		const _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
3262 		if (strncmp(extension->policyname, policyname, sizeof(extension->policyname)) == 0) {
3263 			if (__improbable(exec_spawnattr_validate_policyext_data(px_s, extension))) {
3264 				panic("invalid mac policy extension data");
3265 			}
3266 			if (lenp != NULL) {
3267 				*lenp = (size_t)extension->datalen;
3268 			}
3269 			return (void *)((uintptr_t)px_s->data + extension->dataoff);
3270 		}
3271 	}
3272 
3273 	if (lenp != NULL) {
3274 		*lenp = 0;
3275 	}
3276 	return NULL;
3277 }
3278 
3279 static int
spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc * px_args,struct ip_px_smpx_s * pxsp)3280 spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc *px_args,
3281     struct ip_px_smpx_s *pxsp)
3282 {
3283 	_posix_spawn_mac_policy_extensions_t psmx = NULL;
3284 	uint8_t *data = NULL;
3285 	uint64_t datalen = 0;
3286 	uint64_t dataoff = 0;
3287 	int error = 0;
3288 
3289 	bzero(pxsp, sizeof(*pxsp));
3290 
3291 	if (px_args->mac_extensions_size < PS_MAC_EXTENSIONS_SIZE(1) ||
3292 	    px_args->mac_extensions_size > PAGE_SIZE) {
3293 		error = EINVAL;
3294 		goto bad;
3295 	}
3296 
3297 	psmx = kalloc_data(px_args->mac_extensions_size, Z_WAITOK);
3298 	if (psmx == NULL) {
3299 		error = ENOMEM;
3300 		goto bad;
3301 	}
3302 
3303 	error = copyin(px_args->mac_extensions, psmx, px_args->mac_extensions_size);
3304 	if (error) {
3305 		goto bad;
3306 	}
3307 
3308 	size_t extsize = PS_MAC_EXTENSIONS_SIZE(psmx->psmx_count);
3309 	if (extsize == 0 || extsize > px_args->mac_extensions_size) {
3310 		error = EINVAL;
3311 		goto bad;
3312 	}
3313 
3314 	for (int i = 0; i < psmx->psmx_count; i++) {
3315 		_ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
3316 		if (extension->datalen == 0 || extension->datalen > PAGE_SIZE) {
3317 			error = EINVAL;
3318 			goto bad;
3319 		}
3320 		if (__improbable(os_add_overflow(datalen, extension->datalen, &datalen))) {
3321 			error = ENOMEM;
3322 			goto bad;
3323 		}
3324 	}
3325 
3326 	data = kalloc_data((vm_size_t)datalen, Z_WAITOK);
3327 	if (data == NULL) {
3328 		error = ENOMEM;
3329 		goto bad;
3330 	}
3331 
3332 	for (int i = 0; i < psmx->psmx_count; i++) {
3333 		_ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
3334 
3335 #if !__LP64__
3336 		if (extension->data > UINT32_MAX) {
3337 			goto bad;
3338 		}
3339 #endif
3340 		error = copyin((user_addr_t)extension->data, &data[dataoff], (size_t)extension->datalen);
3341 		if (error) {
3342 			error = ENOMEM;
3343 			goto bad;
3344 		}
3345 		extension->dataoff = dataoff;
3346 		dataoff += extension->datalen;
3347 	}
3348 
3349 	pxsp->array = psmx;
3350 	pxsp->data = data;
3351 	pxsp->datalen = datalen;
3352 	return 0;
3353 
3354 bad:
3355 	kfree_data(psmx, px_args->mac_extensions_size);
3356 	kfree_data(data, (vm_size_t)datalen);
3357 	return error;
3358 }
3359 #endif /* CONFIG_MACF */
3360 
3361 #if CONFIG_COALITIONS
3362 static inline void
spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES])3363 spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES])
3364 {
3365 	for (int c = 0; c < COALITION_NUM_TYPES; c++) {
3366 		if (coal[c]) {
3367 			coalition_remove_active(coal[c]);
3368 			coalition_release(coal[c]);
3369 		}
3370 	}
3371 }
3372 #endif
3373 
3374 #if CONFIG_PERSONAS
3375 static int
spawn_validate_persona(struct _posix_spawn_persona_info * px_persona)3376 spawn_validate_persona(struct _posix_spawn_persona_info *px_persona)
3377 {
3378 	int error = 0;
3379 	struct persona *persona = NULL;
3380 	kauth_cred_t mycred = kauth_cred_get();
3381 
3382 	if (!IOCurrentTaskHasEntitlement( PERSONA_MGMT_ENTITLEMENT)) {
3383 		return EPERM;
3384 	}
3385 
3386 	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
3387 		if (px_persona->pspi_ngroups > NGROUPS_MAX) {
3388 			return EINVAL;
3389 		}
3390 	}
3391 
3392 	persona = persona_lookup(px_persona->pspi_id);
3393 	if (!persona) {
3394 		return ESRCH;
3395 	}
3396 
3397 	// non-root process should not be allowed to set persona with uid/gid 0
3398 	if (!kauth_cred_issuser(mycred) &&
3399 	    (px_persona->pspi_uid == 0 || px_persona->pspi_gid == 0)) {
3400 		return EPERM;
3401 	}
3402 
3403 	persona_put(persona);
3404 	return error;
3405 }
3406 
3407 static bool
kauth_cred_model_setpersona(kauth_cred_t model,struct _posix_spawn_persona_info * px_persona)3408 kauth_cred_model_setpersona(
3409 	kauth_cred_t            model,
3410 	struct _posix_spawn_persona_info *px_persona)
3411 {
3412 	bool updated = false;
3413 
3414 	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_UID) {
3415 		updated |= kauth_cred_model_setresuid(model,
3416 		    px_persona->pspi_uid,
3417 		    px_persona->pspi_uid,
3418 		    px_persona->pspi_uid,
3419 		    KAUTH_UID_NONE);
3420 	}
3421 
3422 	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GID) {
3423 		updated |= kauth_cred_model_setresgid(model,
3424 		    px_persona->pspi_gid,
3425 		    px_persona->pspi_gid,
3426 		    px_persona->pspi_gid);
3427 	}
3428 
3429 	if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
3430 		updated |= kauth_cred_model_setgroups(model,
3431 		    px_persona->pspi_groups,
3432 		    px_persona->pspi_ngroups,
3433 		    px_persona->pspi_gmuid);
3434 	}
3435 
3436 	return updated;
3437 }
3438 
3439 static int
spawn_persona_adopt(proc_t p,struct _posix_spawn_persona_info * px_persona)3440 spawn_persona_adopt(proc_t p, struct _posix_spawn_persona_info *px_persona)
3441 {
3442 	struct persona *persona = NULL;
3443 
3444 	/*
3445 	 * we want to spawn into the given persona, but we want to override
3446 	 * the kauth with a different UID/GID combo
3447 	 */
3448 	persona = persona_lookup(px_persona->pspi_id);
3449 	if (!persona) {
3450 		return ESRCH;
3451 	}
3452 
3453 	return persona_proc_adopt(p, persona,
3454 	           ^bool (kauth_cred_t parent __unused, kauth_cred_t model) {
3455 		return kauth_cred_model_setpersona(model, px_persona);
3456 	});
3457 }
3458 #endif
3459 
3460 #if __arm64__
3461 #if DEVELOPMENT || DEBUG
3462 TUNABLE(int, legacy_footprint_entitlement_mode, "legacy_footprint_entitlement_mode",
3463     LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE);
3464 
3465 __startup_func
3466 static void
legacy_footprint_entitlement_mode_init(void)3467 legacy_footprint_entitlement_mode_init(void)
3468 {
3469 	/*
3470 	 * legacy_footprint_entitlement_mode specifies the behavior we want associated
3471 	 * with the entitlement. The supported modes are:
3472 	 *
3473 	 * LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE:
3474 	 *	Indicates that we want every process to have the memory accounting
3475 	 *	that is available in iOS 12.0 and beyond.
3476 	 *
3477 	 * LEGACY_FOOTPRINT_ENTITLEMENT_IOS11_ACCT:
3478 	 *	Indicates that for every process that has the 'legacy footprint entitlement',
3479 	 *      we want to give it the old iOS 11.0 accounting behavior which accounted some
3480 	 *	of the process's memory to the kernel.
3481 	 *
3482 	 * LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE:
3483 	 *      Indicates that for every process that has the 'legacy footprint entitlement',
3484 	 *	we want it to have a higher memory limit which will help them acclimate to the
3485 	 *	iOS 12.0 (& beyond) accounting behavior that does the right accounting.
3486 	 *      The bonus added to the system-wide task limit to calculate this higher memory limit
3487 	 *      is available in legacy_footprint_bonus_mb.
3488 	 */
3489 
3490 	if (legacy_footprint_entitlement_mode < LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE ||
3491 	    legacy_footprint_entitlement_mode > LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE) {
3492 		legacy_footprint_entitlement_mode = LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE;
3493 	}
3494 }
3495 STARTUP(TUNABLES, STARTUP_RANK_MIDDLE, legacy_footprint_entitlement_mode_init);
3496 #else
3497 const int legacy_footprint_entitlement_mode = LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE;
3498 #endif
3499 
3500 static inline void
proc_legacy_footprint_entitled(proc_t p,task_t task)3501 proc_legacy_footprint_entitled(proc_t p, task_t task)
3502 {
3503 #pragma unused(p)
3504 	boolean_t legacy_footprint_entitled;
3505 
3506 	switch (legacy_footprint_entitlement_mode) {
3507 	case LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE:
3508 		/* the entitlement is ignored */
3509 		break;
3510 	case LEGACY_FOOTPRINT_ENTITLEMENT_IOS11_ACCT:
3511 		/* the entitlement grants iOS11 legacy accounting */
3512 		legacy_footprint_entitled = memorystatus_task_has_legacy_footprint_entitlement(proc_task(p));
3513 		if (legacy_footprint_entitled) {
3514 			task_set_legacy_footprint(task);
3515 		}
3516 		break;
3517 	case LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE:
3518 		/* the entitlement grants a footprint limit increase */
3519 		legacy_footprint_entitled = memorystatus_task_has_legacy_footprint_entitlement(proc_task(p));
3520 		if (legacy_footprint_entitled) {
3521 			task_set_extra_footprint_limit(task);
3522 		}
3523 		break;
3524 	default:
3525 		break;
3526 	}
3527 }
3528 
3529 static inline void
proc_ios13extended_footprint_entitled(proc_t p,task_t task)3530 proc_ios13extended_footprint_entitled(proc_t p, task_t task)
3531 {
3532 #pragma unused(p)
3533 	boolean_t ios13extended_footprint_entitled;
3534 
3535 	/* the entitlement grants a footprint limit increase */
3536 	ios13extended_footprint_entitled = memorystatus_task_has_ios13extended_footprint_limit(proc_task(p));
3537 	if (ios13extended_footprint_entitled) {
3538 		task_set_ios13extended_footprint_limit(task);
3539 	}
3540 }
3541 
3542 static inline void
proc_increased_memory_limit_entitled(proc_t p,task_t task)3543 proc_increased_memory_limit_entitled(proc_t p, task_t task)
3544 {
3545 	if (memorystatus_task_has_increased_debugging_memory_limit_entitlement(task)) {
3546 		memorystatus_act_on_entitled_developer_task_limit(p);
3547 	} else if (memorystatus_task_has_increased_memory_limit_entitlement(task)) {
3548 		memorystatus_act_on_entitled_task_limit(p);
3549 	}
3550 }
3551 
3552 /*
3553  * Check for any of the various entitlements that permit a higher
3554  * task footprint limit or alternate accounting and apply them.
3555  */
3556 static inline void
proc_footprint_entitlement_hacks(proc_t p,task_t task)3557 proc_footprint_entitlement_hacks(proc_t p, task_t task)
3558 {
3559 	proc_legacy_footprint_entitled(p, task);
3560 	proc_ios13extended_footprint_entitled(p, task);
3561 	proc_increased_memory_limit_entitled(p, task);
3562 }
3563 #endif /* __arm64__ */
3564 
3565 /*
3566  * Processes with certain entitlements are granted a jumbo-size VM map.
3567  */
3568 static inline void
proc_apply_jit_and_vm_policies(struct image_params * imgp,proc_t p,task_t task)3569 proc_apply_jit_and_vm_policies(struct image_params *imgp, proc_t p, task_t task)
3570 {
3571 #if CONFIG_MACF
3572 	bool jit_entitled = false;
3573 #endif /* CONFIG_MACF */
3574 	bool needs_jumbo_va = false;
3575 	bool needs_extra_jumbo_va = false;
3576 	struct _posix_spawnattr *psa = imgp->ip_px_sa;
3577 
3578 #if CONFIG_MACF
3579 	jit_entitled = (mac_proc_check_map_anon(p, proc_ucred_unsafe(p),
3580 	    0, 0, 0, MAP_JIT, NULL) == 0);
3581 	needs_jumbo_va = jit_entitled || IOTaskHasEntitlement(task,
3582 	    "com.apple.developer.kernel.extended-virtual-addressing") ||
3583 	    memorystatus_task_has_increased_memory_limit_entitlement(task) ||
3584 	    memorystatus_task_has_increased_debugging_memory_limit_entitlement(task);
3585 #else
3586 #pragma unused(p)
3587 #endif /* CONFIG_MACF */
3588 
3589 
3590 	if (needs_jumbo_va) {
3591 		vm_map_set_jumbo(get_task_map(task));
3592 	}
3593 
3594 	if (psa && psa->psa_max_addr) {
3595 		vm_map_set_max_addr(get_task_map(task), psa->psa_max_addr, false);
3596 	}
3597 
3598 #if CONFIG_MAP_RANGES
3599 	if ((task_has_hardened_heap(task) ||
3600 	    (task_get_platform_restrictions_version(task) == 1) ||
3601 	    task_get_platform_binary(task)) && !proc_is_simulated(p)) {
3602 		/*
3603 		 * This must be done last as it needs to observe
3604 		 * any kind of VA space growth that was requested.
3605 		 * This is used by the secure allocator, so
3606 		 * must be applied to all platform restrictions binaries
3607 		 */
3608 #if XNU_TARGET_OS_IOS && EXTENDED_USER_VA_SUPPORT
3609 		needs_extra_jumbo_va = IOTaskHasEntitlement(task,
3610 		    "com.apple.kernel.large-file-virtual-addressing");
3611 #endif /* XNU_TARGET_OS_IOS && EXTENDED_USER_VA_SUPPORT */
3612 		vm_map_range_configure(get_task_map(task), needs_extra_jumbo_va);
3613 	}
3614 #else
3615 #pragma unused(needs_extra_jumbo_va)
3616 #endif /* CONFIG_MAP_RANGES */
3617 
3618 #if CONFIG_MACF
3619 	if (jit_entitled) {
3620 		vm_map_set_jit_entitled(get_task_map(task));
3621 
3622 	}
3623 #endif /* CONFIG_MACF */
3624 
3625 #if XNU_TARGET_OS_OSX
3626 	/* TPRO cannot be enforced on binaries that load 3P plugins on macos - rdar://107420220 */
3627 	const bool task_loads_3P_plugins = imgp->ip_flags & IMGPF_3P_PLUGINS;
3628 #endif /* XNU_TARGET_OS_OSX */
3629 
3630 	if (task_has_tpro(task)
3631 #if XNU_TARGET_OS_OSX
3632 	    && !task_loads_3P_plugins
3633 #endif /* XNU_TARGET_OS_OSX */
3634 	    ) {
3635 		/*
3636 		 * Pre-emptively disable TPRO remapping for
3637 		 * platform restrictions binaries (which do not load 3P plugins)
3638 		 */
3639 		vm_map_set_tpro_enforcement(get_task_map(task));
3640 	}
3641 }
3642 
3643 static int
spawn_posix_cred_adopt(proc_t p,struct _posix_spawn_posix_cred_info * px_pcred_info)3644 spawn_posix_cred_adopt(proc_t p,
3645     struct _posix_spawn_posix_cred_info *px_pcred_info)
3646 {
3647 	int error = 0;
3648 
3649 	if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GID) {
3650 		struct setgid_args args = {
3651 			.gid = px_pcred_info->pspci_gid,
3652 		};
3653 		error = setgid(p, &args, NULL);
3654 		if (error) {
3655 			return error;
3656 		}
3657 	}
3658 
3659 	if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
3660 		error = setgroups_internal(p,
3661 		    px_pcred_info->pspci_ngroups,
3662 		    px_pcred_info->pspci_groups,
3663 		    px_pcred_info->pspci_gmuid);
3664 		if (error) {
3665 			return error;
3666 		}
3667 	}
3668 
3669 	if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_UID) {
3670 		struct setuid_args args = {
3671 			.uid = px_pcred_info->pspci_uid,
3672 		};
3673 		error = setuid(p, &args, NULL);
3674 		if (error) {
3675 			return error;
3676 		}
3677 	}
3678 	return 0;
3679 }
3680 
3681 /*
3682  * posix_spawn
3683  *
3684  * Parameters:	uap->pid		Pointer to pid return area
3685  *		uap->fname		File name to exec
3686  *		uap->argp		Argument list
3687  *		uap->envp		Environment list
3688  *
3689  * Returns:	0			Success
3690  *		EINVAL			Invalid argument
3691  *		ENOTSUP			Not supported
3692  *		ENOEXEC			Executable file format error
3693  *	exec_activate_image:EINVAL	Invalid argument
3694  *	exec_activate_image:EACCES	Permission denied
3695  *	exec_activate_image:EINTR	Interrupted function
3696  *	exec_activate_image:ENOMEM	Not enough space
3697  *	exec_activate_image:EFAULT	Bad address
3698  *	exec_activate_image:ENAMETOOLONG	Filename too long
3699  *	exec_activate_image:ENOEXEC	Executable file format error
3700  *	exec_activate_image:ETXTBSY	Text file busy [misuse of error code]
3701  *	exec_activate_image:EAUTH	Image decryption failed
3702  *	exec_activate_image:EBADEXEC	The executable is corrupt/unknown
3703  *	exec_activate_image:???
3704  *	mac_execve_enter:???
3705  *
3706  * TODO:	Expect to need __mac_posix_spawn() at some point...
3707  *		Handle posix_spawnattr_t
3708  *		Handle posix_spawn_file_actions_t
3709  */
3710 int
posix_spawn(proc_t ap,struct posix_spawn_args * uap,int32_t * retval)3711 posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval)
3712 {
3713 	proc_t p = ap;
3714 	user_addr_t pid = uap->pid;
3715 	int ival[2];            /* dummy retval for setpgid() */
3716 	char *subsystem_root_path = NULL;
3717 	struct image_params *imgp = NULL;
3718 	struct vnode_attr *vap = NULL;
3719 	struct vnode_attr *origvap = NULL;
3720 	struct uthread  *uthread = 0;   /* compiler complains if not set to 0*/
3721 	int error, sig;
3722 	int is_64 = IS_64BIT_PROCESS(p);
3723 	struct vfs_context context;
3724 	struct user__posix_spawn_args_desc px_args = {};
3725 	struct _posix_spawnattr px_sa = {};
3726 	_posix_spawn_file_actions_t px_sfap = NULL;
3727 	_posix_spawn_port_actions_t px_spap = NULL;
3728 	struct __kern_sigaction vec;
3729 	boolean_t spawn_no_exec = FALSE;
3730 	boolean_t proc_transit_set = TRUE;
3731 	boolean_t proc_signal_set = TRUE;
3732 	boolean_t exec_done = FALSE;
3733 	os_reason_t exec_failure_reason = NULL;
3734 
3735 	struct exec_port_actions port_actions = { };
3736 	vm_size_t px_sa_offset = offsetof(struct _posix_spawnattr, psa_ports);
3737 	task_t old_task = current_task();
3738 	task_t new_task = NULL;
3739 	boolean_t should_release_proc_ref = FALSE;
3740 	void *inherit = NULL;
3741 	uint8_t crash_behavior = 0;
3742 	uint64_t crash_behavior_deadline = 0;
3743 #if CONFIG_EXCLAVES
3744 	char *task_conclave_id = NULL;
3745 #endif
3746 #if CONFIG_PERSONAS
3747 	struct _posix_spawn_persona_info *px_persona = NULL;
3748 #endif
3749 	struct _posix_spawn_posix_cred_info *px_pcred_info = NULL;
3750 	struct {
3751 		struct image_params imgp;
3752 		struct vnode_attr va;
3753 		struct vnode_attr origva;
3754 	} *__spawn_data;
3755 
3756 	/*
3757 	 * Allocate a big chunk for locals instead of using stack since these
3758 	 * structures are pretty big.
3759 	 */
3760 	__spawn_data = kalloc_type(typeof(*__spawn_data), Z_WAITOK | Z_ZERO);
3761 	if (__spawn_data == NULL) {
3762 		error = ENOMEM;
3763 		goto bad;
3764 	}
3765 	imgp = &__spawn_data->imgp;
3766 	vap = &__spawn_data->va;
3767 	origvap = &__spawn_data->origva;
3768 
3769 	/* Initialize the common data in the image_params structure */
3770 	imgp->ip_user_fname = uap->path;
3771 	imgp->ip_user_argv = uap->argv;
3772 	imgp->ip_user_envv = uap->envp;
3773 	imgp->ip_vattr = vap;
3774 	imgp->ip_origvattr = origvap;
3775 	imgp->ip_vfs_context = &context;
3776 	imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE);
3777 	imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
3778 	imgp->ip_mac_return = 0;
3779 	imgp->ip_px_persona = NULL;
3780 	imgp->ip_px_pcred_info = NULL;
3781 	imgp->ip_cs_error = OS_REASON_NULL;
3782 	imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
3783 	imgp->ip_subsystem_root_path = NULL;
3784 	imgp->ip_inherited_shared_region_id = NULL;
3785 	imgp->ip_inherited_jop_pid = 0;
3786 	uthread_set_exec_data(current_uthread(), imgp);
3787 
3788 	if (uap->adesc != USER_ADDR_NULL) {
3789 		if (is_64) {
3790 			error = copyin(uap->adesc, &px_args, sizeof(px_args));
3791 		} else {
3792 			struct user32__posix_spawn_args_desc px_args32;
3793 
3794 			error = copyin(uap->adesc, &px_args32, sizeof(px_args32));
3795 
3796 			/*
3797 			 * Convert arguments descriptor from external 32 bit
3798 			 * representation to internal 64 bit representation
3799 			 */
3800 			px_args.attr_size = px_args32.attr_size;
3801 			px_args.attrp = CAST_USER_ADDR_T(px_args32.attrp);
3802 			px_args.file_actions_size = px_args32.file_actions_size;
3803 			px_args.file_actions = CAST_USER_ADDR_T(px_args32.file_actions);
3804 			px_args.port_actions_size = px_args32.port_actions_size;
3805 			px_args.port_actions = CAST_USER_ADDR_T(px_args32.port_actions);
3806 			px_args.mac_extensions_size = px_args32.mac_extensions_size;
3807 			px_args.mac_extensions = CAST_USER_ADDR_T(px_args32.mac_extensions);
3808 			px_args.coal_info_size = px_args32.coal_info_size;
3809 			px_args.coal_info = CAST_USER_ADDR_T(px_args32.coal_info);
3810 			px_args.persona_info_size = px_args32.persona_info_size;
3811 			px_args.persona_info = CAST_USER_ADDR_T(px_args32.persona_info);
3812 			px_args.posix_cred_info_size = px_args32.posix_cred_info_size;
3813 			px_args.posix_cred_info = CAST_USER_ADDR_T(px_args32.posix_cred_info);
3814 			px_args.subsystem_root_path_size = px_args32.subsystem_root_path_size;
3815 			px_args.subsystem_root_path = CAST_USER_ADDR_T(px_args32.subsystem_root_path);
3816 			px_args.conclave_id_size = px_args32.conclave_id_size;
3817 			px_args.conclave_id = CAST_USER_ADDR_T(px_args32.conclave_id);
3818 		}
3819 		if (error) {
3820 			goto bad;
3821 		}
3822 
3823 		if (px_args.attr_size != 0) {
3824 			/*
3825 			 * We are not copying the port_actions pointer,
3826 			 * because we already have it from px_args.
3827 			 * This is a bit fragile: <rdar://problem/16427422>
3828 			 */
3829 
3830 			if ((error = copyin(px_args.attrp, &px_sa, px_sa_offset)) != 0) {
3831 				goto bad;
3832 			}
3833 
3834 			imgp->ip_px_sa = &px_sa;
3835 		}
3836 		if (px_args.file_actions_size != 0) {
3837 			/* Limit file_actions to allowed number of open files */
3838 			size_t maxfa_size = PSF_ACTIONS_SIZE(proc_limitgetcur_nofile(p));
3839 
3840 			if (px_args.file_actions_size < PSF_ACTIONS_SIZE(1) ||
3841 			    maxfa_size == 0 || px_args.file_actions_size > maxfa_size) {
3842 				error = EINVAL;
3843 				goto bad;
3844 			}
3845 
3846 			px_sfap = kalloc_data(px_args.file_actions_size, Z_WAITOK);
3847 			if (px_sfap == NULL) {
3848 				error = ENOMEM;
3849 				goto bad;
3850 			}
3851 			imgp->ip_px_sfa = px_sfap;
3852 
3853 			if ((error = copyin(px_args.file_actions, px_sfap,
3854 			    px_args.file_actions_size)) != 0) {
3855 				goto bad;
3856 			}
3857 
3858 			/* Verify that the action count matches the struct size */
3859 			size_t psfsize = PSF_ACTIONS_SIZE(px_sfap->psfa_act_count);
3860 			if (psfsize == 0 || psfsize != px_args.file_actions_size) {
3861 				error = EINVAL;
3862 				goto bad;
3863 			}
3864 		}
3865 		if (px_args.port_actions_size != 0) {
3866 			/* Limit port_actions to one page of data */
3867 			if (px_args.port_actions_size < PS_PORT_ACTIONS_SIZE(1) ||
3868 			    px_args.port_actions_size > PAGE_SIZE) {
3869 				error = EINVAL;
3870 				goto bad;
3871 			}
3872 
3873 			px_spap = kalloc_data(px_args.port_actions_size, Z_WAITOK);
3874 			if (px_spap == NULL) {
3875 				error = ENOMEM;
3876 				goto bad;
3877 			}
3878 			imgp->ip_px_spa = px_spap;
3879 
3880 			if ((error = copyin(px_args.port_actions, px_spap,
3881 			    px_args.port_actions_size)) != 0) {
3882 				goto bad;
3883 			}
3884 
3885 			/* Verify that the action count matches the struct size */
3886 			size_t pasize = PS_PORT_ACTIONS_SIZE(px_spap->pspa_count);
3887 			if (pasize == 0 || pasize != px_args.port_actions_size) {
3888 				error = EINVAL;
3889 				goto bad;
3890 			}
3891 		}
3892 #if CONFIG_PERSONAS
3893 		/* copy in the persona info */
3894 		if (px_args.persona_info_size != 0 && px_args.persona_info != 0) {
3895 			/* for now, we need the exact same struct in user space */
3896 			if (px_args.persona_info_size != sizeof(*px_persona)) {
3897 				error = ERANGE;
3898 				goto bad;
3899 			}
3900 
3901 			px_persona = kalloc_data(px_args.persona_info_size, Z_WAITOK);
3902 			if (px_persona == NULL) {
3903 				error = ENOMEM;
3904 				goto bad;
3905 			}
3906 			imgp->ip_px_persona = px_persona;
3907 
3908 			if ((error = copyin(px_args.persona_info, px_persona,
3909 			    px_args.persona_info_size)) != 0) {
3910 				goto bad;
3911 			}
3912 			if ((error = spawn_validate_persona(px_persona)) != 0) {
3913 				goto bad;
3914 			}
3915 		}
3916 #endif
3917 		/* copy in the posix cred info */
3918 		if (px_args.posix_cred_info_size != 0 && px_args.posix_cred_info != 0) {
3919 			/* for now, we need the exact same struct in user space */
3920 			if (px_args.posix_cred_info_size != sizeof(*px_pcred_info)) {
3921 				error = ERANGE;
3922 				goto bad;
3923 			}
3924 
3925 			if (!kauth_cred_issuser(kauth_cred_get())) {
3926 				error = EPERM;
3927 				goto bad;
3928 			}
3929 
3930 			px_pcred_info = kalloc_data(px_args.posix_cred_info_size, Z_WAITOK);
3931 			if (px_pcred_info == NULL) {
3932 				error = ENOMEM;
3933 				goto bad;
3934 			}
3935 			imgp->ip_px_pcred_info = px_pcred_info;
3936 
3937 			if ((error = copyin(px_args.posix_cred_info, px_pcred_info,
3938 			    px_args.posix_cred_info_size)) != 0) {
3939 				goto bad;
3940 			}
3941 
3942 			if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
3943 				if (px_pcred_info->pspci_ngroups > NGROUPS_MAX) {
3944 					error = EINVAL;
3945 					goto bad;
3946 				}
3947 			}
3948 		}
3949 #if CONFIG_MACF
3950 		if (px_args.mac_extensions_size != 0) {
3951 			if ((error = spawn_copyin_macpolicyinfo(&px_args, (struct ip_px_smpx_s *)&imgp->ip_px_smpx)) != 0) {
3952 				goto bad;
3953 			}
3954 		}
3955 #endif /* CONFIG_MACF */
3956 		if ((px_args.subsystem_root_path_size > 0) && (px_args.subsystem_root_path_size <= MAXPATHLEN)) {
3957 			/*
3958 			 * If a valid-looking subsystem root has been
3959 			 * specified...
3960 			 */
3961 			if (IOTaskHasEntitlement(old_task, SPAWN_SUBSYSTEM_ROOT_ENTITLEMENT)) {
3962 				/*
3963 				 * ...AND the parent has the entitlement, copy
3964 				 * the subsystem root path in.
3965 				 */
3966 				subsystem_root_path = zalloc_flags(ZV_NAMEI,
3967 				    Z_WAITOK | Z_ZERO | Z_NOFAIL);
3968 
3969 				if ((error = copyin(px_args.subsystem_root_path, subsystem_root_path, px_args.subsystem_root_path_size))) {
3970 					goto bad;
3971 				}
3972 
3973 				/* Paranoia */
3974 				subsystem_root_path[px_args.subsystem_root_path_size - 1] = 0;
3975 			}
3976 		}
3977 #if CONFIG_EXCLAVES
3978 
3979 		/*
3980 		 * Calling exclaves_boot_wait() ensures that the conclave name
3981 		 * id will only be set when exclaves are actually
3982 		 * supported/enabled. In practice this will never actually block
3983 		 * as by the time this is called the system will have booted to
3984 		 * EXCLAVECORE if it's supported/enabled.
3985 		 */
3986 		if ((px_args.conclave_id_size > 0) && (px_args.conclave_id_size <= MAXCONCLAVENAME) &&
3987 		    (exclaves_boot_wait(EXCLAVES_BOOT_STAGE_EXCLAVECORE) == KERN_SUCCESS)) {
3988 			if (px_args.conclave_id) {
3989 				if (imgp->ip_px_sa != NULL && (px_sa.psa_flags & POSIX_SPAWN_SETEXEC)) {
3990 					/* Conclave id could be set only for true spawn */
3991 					error = EINVAL;
3992 					goto bad;
3993 				}
3994 				task_conclave_id = kalloc_data(MAXCONCLAVENAME,
3995 				    Z_WAITOK | Z_ZERO | Z_NOFAIL);
3996 				if ((error = copyin(px_args.conclave_id, task_conclave_id, MAXCONCLAVENAME))) {
3997 					goto bad;
3998 				}
3999 				task_conclave_id[MAXCONCLAVENAME - 1] = 0;
4000 			}
4001 		}
4002 #endif
4003 	}
4004 
4005 	if (IOTaskHasEntitlement(old_task, SPAWN_SET_PANIC_CRASH_BEHAVIOR)) {
4006 		/* Truncate to uint8_t since we only support 2 flags for now */
4007 		crash_behavior = (uint8_t)px_sa.psa_crash_behavior;
4008 		crash_behavior_deadline = px_sa.psa_crash_behavior_deadline;
4009 	}
4010 
4011 	/* set uthread to parent */
4012 	uthread = current_uthread();
4013 
4014 	/*
4015 	 * <rdar://6640530>; this does not result in a behaviour change
4016 	 * relative to Leopard, so there should not be any existing code
4017 	 * which depends on it.
4018 	 */
4019 
4020 	if (imgp->ip_px_sa != NULL) {
4021 		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4022 		if ((psa->psa_options & PSA_OPTION_PLUGIN_HOST_DISABLE_A_KEYS) == PSA_OPTION_PLUGIN_HOST_DISABLE_A_KEYS) {
4023 			imgp->ip_flags |= IMGPF_PLUGIN_HOST_DISABLE_A_KEYS;
4024 		}
4025 
4026 #if (DEVELOPMENT || DEBUG)
4027 		if ((psa->psa_options & PSA_OPTION_ALT_ROSETTA) == PSA_OPTION_ALT_ROSETTA) {
4028 			imgp->ip_flags |= (IMGPF_ROSETTA | IMGPF_ALT_ROSETTA);
4029 		}
4030 #endif /* (DEVELOPMENT || DEBUG) */
4031 
4032 
4033 		if ((error = exec_validate_spawnattr_policy(psa->psa_apptype)) != 0) {
4034 			goto bad;
4035 		}
4036 	}
4037 
4038 	/*
4039 	 * If we don't have the extension flag that turns "posix_spawn()"
4040 	 * into "execve() with options", then we will be creating a new
4041 	 * process which does not inherit memory from the parent process,
4042 	 * which is one of the most expensive things about using fork()
4043 	 * and execve().
4044 	 */
4045 	if (imgp->ip_px_sa == NULL || !(px_sa.psa_flags & POSIX_SPAWN_SETEXEC)) {
4046 		/* Set the new task's coalition, if it is requested.  */
4047 		coalition_t coal[COALITION_NUM_TYPES] = { COALITION_NULL };
4048 #if CONFIG_COALITIONS
4049 		int i, ncoals;
4050 		kern_return_t kr = KERN_SUCCESS;
4051 		struct _posix_spawn_coalition_info coal_info;
4052 		int coal_role[COALITION_NUM_TYPES];
4053 
4054 		if (imgp->ip_px_sa == NULL || !px_args.coal_info) {
4055 			goto do_fork1;
4056 		}
4057 
4058 		memset(&coal_info, 0, sizeof(coal_info));
4059 
4060 		if (px_args.coal_info_size > sizeof(coal_info)) {
4061 			px_args.coal_info_size = sizeof(coal_info);
4062 		}
4063 		error = copyin(px_args.coal_info,
4064 		    &coal_info, px_args.coal_info_size);
4065 		if (error != 0) {
4066 			goto bad;
4067 		}
4068 
4069 		ncoals = 0;
4070 		for (i = 0; i < COALITION_NUM_TYPES; i++) {
4071 			uint64_t cid = coal_info.psci_info[i].psci_id;
4072 			if (cid != 0) {
4073 				/*
4074 				 * don't allow tasks which are not in a
4075 				 * privileged coalition to spawn processes
4076 				 * into coalitions other than their own
4077 				 */
4078 				if (!task_is_in_privileged_coalition(proc_task(p), i) &&
4079 				    !IOTaskHasEntitlement(proc_task(p), COALITION_SPAWN_ENTITLEMENT)) {
4080 					coal_dbg("ERROR: %d not in privilegd "
4081 					    "coalition of type %d",
4082 					    proc_getpid(p), i);
4083 					spawn_coalitions_release_all(coal);
4084 					error = EPERM;
4085 					goto bad;
4086 				}
4087 
4088 				coal_dbg("searching for coalition id:%llu", cid);
4089 				/*
4090 				 * take a reference and activation on the
4091 				 * coalition to guard against free-while-spawn
4092 				 * races
4093 				 */
4094 				coal[i] = coalition_find_and_activate_by_id(cid);
4095 				if (coal[i] == COALITION_NULL) {
4096 					coal_dbg("could not find coalition id:%llu "
4097 					    "(perhaps it has been terminated or reaped)", cid);
4098 					/*
4099 					 * release any other coalition's we
4100 					 * may have a reference to
4101 					 */
4102 					spawn_coalitions_release_all(coal);
4103 					error = ESRCH;
4104 					goto bad;
4105 				}
4106 				if (coalition_type(coal[i]) != i) {
4107 					coal_dbg("coalition with id:%lld is not of type:%d"
4108 					    " (it's type:%d)", cid, i, coalition_type(coal[i]));
4109 					spawn_coalitions_release_all(coal);
4110 					error = ESRCH;
4111 					goto bad;
4112 				}
4113 				coal_role[i] = coal_info.psci_info[i].psci_role;
4114 				ncoals++;
4115 			}
4116 		}
4117 		if (ncoals < COALITION_NUM_TYPES) {
4118 			/*
4119 			 * If the user is attempting to spawn into a subset of
4120 			 * the known coalition types, then make sure they have
4121 			 * _at_least_ specified a resource coalition. If not,
4122 			 * the following fork1() call will implicitly force an
4123 			 * inheritance from 'p' and won't actually spawn the
4124 			 * new task into the coalitions the user specified.
4125 			 * (also the call to coalitions_set_roles will panic)
4126 			 */
4127 			if (coal[COALITION_TYPE_RESOURCE] == COALITION_NULL) {
4128 				spawn_coalitions_release_all(coal);
4129 				error = EINVAL;
4130 				goto bad;
4131 			}
4132 		}
4133 do_fork1:
4134 #endif /* CONFIG_COALITIONS */
4135 
4136 		/*
4137 		 * note that this will implicitly inherit the
4138 		 * caller's persona (if it exists)
4139 		 */
4140 		error = fork1(p, &imgp->ip_new_thread, PROC_CREATE_SPAWN, coal);
4141 		/* returns a thread and task reference */
4142 
4143 		if (error == 0) {
4144 			new_task = get_threadtask(imgp->ip_new_thread);
4145 		}
4146 #if CONFIG_COALITIONS
4147 		/* set the roles of this task within each given coalition */
4148 		if (error == 0) {
4149 			kr = coalitions_set_roles(coal, new_task, coal_role);
4150 			if (kr != KERN_SUCCESS) {
4151 				error = EINVAL;
4152 			}
4153 			if (kdebug_debugid_enabled(MACHDBG_CODE(DBG_MACH_COALITION,
4154 			    MACH_COALITION_ADOPT))) {
4155 				for (i = 0; i < COALITION_NUM_TYPES; i++) {
4156 					if (coal[i] != COALITION_NULL) {
4157 						/*
4158 						 * On 32-bit targets, uniqueid
4159 						 * will get truncated to 32 bits
4160 						 */
4161 						KDBG_RELEASE(MACHDBG_CODE(
4162 							    DBG_MACH_COALITION,
4163 							    MACH_COALITION_ADOPT),
4164 						    coalition_id(coal[i]),
4165 						    get_task_uniqueid(new_task));
4166 					}
4167 				}
4168 			}
4169 		}
4170 
4171 		/* drop our references and activations - fork1() now holds them */
4172 		spawn_coalitions_release_all(coal);
4173 #endif /* CONFIG_COALITIONS */
4174 		if (error != 0) {
4175 			goto bad;
4176 		}
4177 		imgp->ip_flags |= IMGPF_SPAWN;  /* spawn w/o exec */
4178 		spawn_no_exec = TRUE;           /* used in later tests */
4179 	} else {
4180 		/* Adjust the user proc count */
4181 		(void)chgproccnt(kauth_getruid(), 1);
4182 		/*
4183 		 * For execve case, create a new proc, task and thread
4184 		 * but don't make the proc visible to userland. After
4185 		 * image activation, the new proc would take place of
4186 		 * the old proc in pid hash and other lists that make
4187 		 * the proc visible to the system.
4188 		 */
4189 		imgp->ip_new_thread = cloneproc(old_task, NULL, p, CLONEPROC_EXEC);
4190 
4191 		/* task and thread ref returned by cloneproc */
4192 		if (imgp->ip_new_thread == NULL) {
4193 			(void)chgproccnt(kauth_getruid(), -1);
4194 			error = ENOMEM;
4195 			goto bad;
4196 		}
4197 
4198 		new_task = get_threadtask(imgp->ip_new_thread);
4199 		imgp->ip_flags |= IMGPF_EXEC;
4200 	}
4201 
4202 	p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
4203 
4204 	if (spawn_no_exec) {
4205 		/*
4206 		 * We had to wait until this point before firing the
4207 		 * proc:::create probe, otherwise p would not point to the
4208 		 * child process.
4209 		 */
4210 		DTRACE_PROC1(create, proc_t, p);
4211 	}
4212 	assert(p != NULL);
4213 
4214 	if (subsystem_root_path) {
4215 		/* If a subsystem root was specified, swap it in */
4216 		char * old_subsystem_root_path = p->p_subsystem_root_path;
4217 		p->p_subsystem_root_path = subsystem_root_path;
4218 		subsystem_root_path = old_subsystem_root_path;
4219 	}
4220 
4221 	p->p_crash_behavior = crash_behavior;
4222 	p->p_crash_behavior_deadline = crash_behavior_deadline;
4223 
4224 	p->p_crash_count = px_sa.psa_crash_count;
4225 	p->p_throttle_timeout = px_sa.psa_throttle_timeout;
4226 
4227 	/* We'll need the subsystem root for setting up Apple strings */
4228 	imgp->ip_subsystem_root_path = p->p_subsystem_root_path;
4229 
4230 	context.vc_thread = imgp->ip_new_thread;
4231 	context.vc_ucred = proc_ucred_unsafe(p);  /* in init */
4232 
4233 	/*
4234 	 * Post fdt_fork(), pre exec_handle_sugid() - this is where we want
4235 	 * to handle the file_actions.
4236 	 */
4237 
4238 	/* Has spawn file actions? */
4239 	if (imgp->ip_px_sfa != NULL) {
4240 		/*
4241 		 * The POSIX_SPAWN_CLOEXEC_DEFAULT flag
4242 		 * is handled in exec_handle_file_actions().
4243 		 */
4244 #if CONFIG_AUDIT
4245 		/*
4246 		 * The file actions auditing can overwrite the upath of
4247 		 * AUE_POSIX_SPAWN audit record.  Save the audit record.
4248 		 */
4249 		struct kaudit_record *save_uu_ar = uthread->uu_ar;
4250 		uthread->uu_ar = NULL;
4251 #endif
4252 		error = exec_handle_file_actions(imgp,
4253 		    imgp->ip_px_sa != NULL ? px_sa.psa_flags : 0);
4254 #if CONFIG_AUDIT
4255 		/* Restore the AUE_POSIX_SPAWN audit record. */
4256 		uthread->uu_ar = save_uu_ar;
4257 #endif
4258 		if (error != 0) {
4259 			goto bad;
4260 		}
4261 	}
4262 
4263 	/* Has spawn port actions? */
4264 	if (imgp->ip_px_spa != NULL) {
4265 #if CONFIG_AUDIT
4266 		/*
4267 		 * Do the same for the port actions as we did for the file
4268 		 * actions.  Save the AUE_POSIX_SPAWN audit record.
4269 		 */
4270 		struct kaudit_record *save_uu_ar = uthread->uu_ar;
4271 		uthread->uu_ar = NULL;
4272 #endif
4273 		error = exec_handle_port_actions(imgp, &port_actions);
4274 #if CONFIG_AUDIT
4275 		/* Restore the AUE_POSIX_SPAWN audit record. */
4276 		uthread->uu_ar = save_uu_ar;
4277 #endif
4278 		if (error != 0) {
4279 			goto bad;
4280 		}
4281 	}
4282 
4283 	/* Has spawn attr? */
4284 	if (imgp->ip_px_sa != NULL) {
4285 		/*
4286 		 * Reset UID/GID to parent's RUID/RGID; This works only
4287 		 * because the operation occurs before the call
4288 		 * to exec_handle_sugid() by the image activator called
4289 		 * from exec_activate_image().
4290 		 *
4291 		 * POSIX requires that any setuid/setgid bits on the process
4292 		 * image will take precedence over the spawn attributes
4293 		 * (re)setting them.
4294 		 *
4295 		 * Modifications to p_ucred must be guarded using the
4296 		 * proc's ucred lock. This prevents others from accessing
4297 		 * a garbage credential.
4298 		 */
4299 		if (px_sa.psa_flags & POSIX_SPAWN_RESETIDS) {
4300 			kauth_cred_proc_update(p, PROC_SETTOKEN_NONE,
4301 			    ^bool (kauth_cred_t parent __unused, kauth_cred_t model){
4302 				return kauth_cred_model_setuidgid(model,
4303 				kauth_cred_getruid(parent),
4304 				kauth_cred_getrgid(parent));
4305 			});
4306 		}
4307 
4308 		if (imgp->ip_px_pcred_info) {
4309 			if (!spawn_no_exec) {
4310 				error = ENOTSUP;
4311 				goto bad;
4312 			}
4313 
4314 			error = spawn_posix_cred_adopt(p, imgp->ip_px_pcred_info);
4315 			if (error != 0) {
4316 				goto bad;
4317 			}
4318 		}
4319 
4320 #if CONFIG_PERSONAS
4321 		if (imgp->ip_px_persona != NULL) {
4322 			if (!spawn_no_exec) {
4323 				error = ENOTSUP;
4324 				goto bad;
4325 			}
4326 
4327 			/*
4328 			 * If we were asked to spawn a process into a new persona,
4329 			 * do the credential switch now (which may override the UID/GID
4330 			 * inherit done just above). It's important to do this switch
4331 			 * before image activation both for reasons stated above, and
4332 			 * to ensure that the new persona has access to the image/file
4333 			 * being executed.
4334 			 */
4335 			error = spawn_persona_adopt(p, imgp->ip_px_persona);
4336 			if (error != 0) {
4337 				goto bad;
4338 			}
4339 		}
4340 #endif /* CONFIG_PERSONAS */
4341 #if !SECURE_KERNEL
4342 		/*
4343 		 * Disable ASLR for the spawned process.
4344 		 *
4345 		 * But only do so if we are not embedded + RELEASE.
4346 		 * While embedded allows for a boot-arg (-disable_aslr)
4347 		 * to deal with this (which itself is only honored on
4348 		 * DEVELOPMENT or DEBUG builds of xnu), it is often
4349 		 * useful or necessary to disable ASLR on a per-process
4350 		 * basis for unit testing and debugging.
4351 		 */
4352 		if (px_sa.psa_flags & _POSIX_SPAWN_DISABLE_ASLR) {
4353 			OSBitOrAtomic(P_DISABLE_ASLR, &p->p_flag);
4354 		}
4355 #endif /* !SECURE_KERNEL */
4356 
4357 		/* Randomize high bits of ASLR slide */
4358 		if (px_sa.psa_flags & _POSIX_SPAWN_HIGH_BITS_ASLR) {
4359 			imgp->ip_flags |= IMGPF_HIGH_BITS_ASLR;
4360 		}
4361 
4362 #if !SECURE_KERNEL
4363 		/*
4364 		 * Forcibly disallow execution from data pages for the spawned process
4365 		 * even if it would otherwise be permitted by the architecture default.
4366 		 */
4367 		if (px_sa.psa_flags & _POSIX_SPAWN_ALLOW_DATA_EXEC) {
4368 			imgp->ip_flags |= IMGPF_ALLOW_DATA_EXEC;
4369 		}
4370 #endif /* !SECURE_KERNEL */
4371 
4372 #if     __has_feature(ptrauth_calls)
4373 		if (vm_shared_region_reslide_aslr && is_64 && (px_sa.psa_flags & _POSIX_SPAWN_RESLIDE)) {
4374 			imgp->ip_flags |= IMGPF_RESLIDE;
4375 		}
4376 #endif /* __has_feature(ptrauth_calls) */
4377 
4378 		if ((px_sa.psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) ==
4379 		    POSIX_SPAWN_PROC_TYPE_DRIVER) {
4380 			imgp->ip_flags |= IMGPF_DRIVER;
4381 		}
4382 	}
4383 
4384 	/*
4385 	 * Disable ASLR during image activation.  This occurs either if the
4386 	 * _POSIX_SPAWN_DISABLE_ASLR attribute was found above or if
4387 	 * P_DISABLE_ASLR was inherited from the parent process.
4388 	 */
4389 	if (p->p_flag & P_DISABLE_ASLR) {
4390 		imgp->ip_flags |= IMGPF_DISABLE_ASLR;
4391 	}
4392 
4393 	/*
4394 	 * Clear transition flag so we won't hang if exec_activate_image() causes
4395 	 * an automount (and launchd does a proc sysctl to service it).
4396 	 *
4397 	 * <rdar://problem/6848672>, <rdar://problem/5959568>.
4398 	 */
4399 	proc_transend(p, 0);
4400 	proc_transit_set = 0;
4401 
4402 	if (!spawn_no_exec) {
4403 		/*
4404 		 * Clear the signal lock in case of exec, since
4405 		 * image activation uses psignal on child process.
4406 		 */
4407 		proc_signalend(p, 0);
4408 		proc_signal_set = 0;
4409 	}
4410 
4411 #if MAC_SPAWN   /* XXX */
4412 	if (uap->mac_p != USER_ADDR_NULL) {
4413 		error = mac_execve_enter(uap->mac_p, imgp);
4414 		if (error) {
4415 			goto bad;
4416 		}
4417 	}
4418 #endif
4419 	/*
4420 	 * Activate the image.
4421 	 * Warning: If activation failed after point of no return, it returns error
4422 	 * as 0 and pretends the call succeeded.
4423 	 */
4424 	error = exec_activate_image(imgp);
4425 #if defined(HAS_APPLE_PAC)
4426 	const uint8_t disable_user_jop = imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE;
4427 	ml_task_set_jop_pid_from_shared_region(new_task, disable_user_jop);
4428 	ml_task_set_disable_user_jop(new_task, disable_user_jop);
4429 	ml_thread_set_disable_user_jop(imgp->ip_new_thread, disable_user_jop);
4430 	ml_thread_set_jop_pid(imgp->ip_new_thread, new_task);
4431 #endif
4432 
4433 	/*
4434 	 * If you've come here to add support for some new HW feature or some per-process or per-vmmap
4435 	 * or per-pmap flag that needs to be set before the process runs, or are in general lost, here
4436 	 * is some help. This summary was accurate as of Jul 2022. Use git log as needed. This comment
4437 	 * is here to prevent a recurrence of rdar://96307913
4438 	 *
4439 	 * In posix_spawn, following is what happens:
4440 	 * 1. Lots of prep and checking work
4441 	 * 2. Image activation via exec_activate_image(). The new task will get a new pmap here
4442 	 * 3. More prep work. (YOU ARE HERE)
4443 	 * 4. exec_resettextvp() is called
4444 	 * 5. At this point it is safe to check entitlements and code signatures
4445 	 * 6. task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
4446 	 *    The new thread is allowed to run in kernel. It cannot yet get to userland
4447 	 * 7. More things done here. This is your chance to affect the task before it runs in
4448 	 *    userspace
4449 	 * 8. task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
4450 	 *     The new thread is allowed to run in userland
4451 	 */
4452 
4453 	if (error == 0 && !spawn_no_exec) {
4454 		p = proc_exec_switch_task(current_proc(), p, old_task, new_task, imgp, &inherit);
4455 		/* proc ref returned */
4456 		should_release_proc_ref = TRUE;
4457 	}
4458 
4459 	if (error == 0) {
4460 		/* process completed the exec, but may have failed after point of no return */
4461 		exec_done = TRUE;
4462 	}
4463 
4464 #if CONFIG_EXCLAVES
4465 	if (!error && task_conclave_id != NULL) {
4466 		kern_return_t kr;
4467 		kr = task_add_conclave(new_task, imgp->ip_vp, (int64_t)imgp->ip_arch_offset,
4468 		    task_conclave_id);
4469 		if (kr != KERN_SUCCESS) {
4470 			error = EINVAL;
4471 			goto bad;
4472 		}
4473 	}
4474 #endif
4475 
4476 	if (!error && imgp->ip_px_sa != NULL) {
4477 		thread_t child_thread = imgp->ip_new_thread;
4478 		uthread_t child_uthread = get_bsdthread_info(child_thread);
4479 
4480 		/*
4481 		 * Because of POSIX_SPAWN_SETEXEC, we need to handle this after image
4482 		 * activation, else when image activation fails (before the point of no
4483 		 * return) would leave the parent process in a modified state.
4484 		 */
4485 		if (px_sa.psa_flags & POSIX_SPAWN_SETPGROUP) {
4486 			struct setpgid_args spga;
4487 			spga.pid = proc_getpid(p);
4488 			spga.pgid = px_sa.psa_pgroup;
4489 			/*
4490 			 * Effectively, call setpgid() system call; works
4491 			 * because there are no pointer arguments.
4492 			 */
4493 			if ((error = setpgid(p, &spga, ival)) != 0) {
4494 				goto bad_px_sa;
4495 			}
4496 		}
4497 
4498 		if (px_sa.psa_flags & POSIX_SPAWN_SETSID) {
4499 			error = setsid_internal(p);
4500 			if (error != 0) {
4501 				goto bad_px_sa;
4502 			}
4503 		}
4504 
4505 		/*
4506 		 * If we have a spawn attr, and it contains signal related flags,
4507 		 * the we need to process them in the "context" of the new child
4508 		 * process, so we have to process it following image activation,
4509 		 * prior to making the thread runnable in user space.  This is
4510 		 * necessitated by some signal information being per-thread rather
4511 		 * than per-process, and we don't have the new allocation in hand
4512 		 * until after the image is activated.
4513 		 */
4514 
4515 		/*
4516 		 * Mask a list of signals, instead of them being unmasked, if
4517 		 * they were unmasked in the parent; note that some signals
4518 		 * are not maskable.
4519 		 */
4520 		if (px_sa.psa_flags & POSIX_SPAWN_SETSIGMASK) {
4521 			child_uthread->uu_sigmask = (px_sa.psa_sigmask & ~sigcantmask);
4522 		}
4523 		/*
4524 		 * Default a list of signals instead of ignoring them, if
4525 		 * they were ignored in the parent.  Note that we pass
4526 		 * spawn_no_exec to setsigvec() to indicate that we called
4527 		 * fork1() and therefore do not need to call proc_signalstart()
4528 		 * internally.
4529 		 */
4530 		if (px_sa.psa_flags & POSIX_SPAWN_SETSIGDEF) {
4531 			vec.sa_handler = SIG_DFL;
4532 			vec.sa_tramp = 0;
4533 			vec.sa_mask = 0;
4534 			vec.sa_flags = 0;
4535 			for (sig = 1; sig < NSIG; sig++) {
4536 				if (px_sa.psa_sigdefault & (1 << (sig - 1))) {
4537 					error = setsigvec(p, child_thread, sig, &vec, spawn_no_exec);
4538 				}
4539 			}
4540 		}
4541 
4542 		/*
4543 		 * Activate the CPU usage monitor, if requested. This is done via a task-wide, per-thread CPU
4544 		 * usage limit, which will generate a resource exceeded exception if any one thread exceeds the
4545 		 * limit.
4546 		 *
4547 		 * Userland gives us interval in seconds, and the kernel SPI expects nanoseconds.
4548 		 */
4549 		if ((px_sa.psa_cpumonitor_percent != 0) && (px_sa.psa_cpumonitor_percent < UINT8_MAX)) {
4550 			/*
4551 			 * Always treat a CPU monitor activation coming from spawn as entitled. Requiring
4552 			 * an entitlement to configure the monitor a certain way seems silly, since
4553 			 * whomever is turning it on could just as easily choose not to do so.
4554 			 */
4555 			error = proc_set_task_ruse_cpu(proc_task(p),
4556 			    TASK_POLICY_RESOURCE_ATTRIBUTE_NOTIFY_EXC,
4557 			    (uint8_t)px_sa.psa_cpumonitor_percent,
4558 			    px_sa.psa_cpumonitor_interval * NSEC_PER_SEC,
4559 			    0, TRUE);
4560 		}
4561 
4562 
4563 		if (px_pcred_info &&
4564 		    (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_LOGIN)) {
4565 			/*
4566 			 * setlogin() must happen after setsid()
4567 			 */
4568 			setlogin_internal(p, px_pcred_info->pspci_login);
4569 		}
4570 
4571 bad_px_sa:
4572 		if (error != 0) {
4573 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
4574 			    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_PSATTR, 0, 0);
4575 			exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_PSATTR);
4576 		}
4577 	}
4578 
4579 bad:
4580 
4581 	if (error == 0) {
4582 		/* reset delay idle sleep status if set */
4583 #if CONFIG_DELAY_IDLE_SLEEP
4584 		if ((p->p_flag & P_DELAYIDLESLEEP) == P_DELAYIDLESLEEP) {
4585 			OSBitAndAtomic(~((uint32_t)P_DELAYIDLESLEEP), &p->p_flag);
4586 		}
4587 #endif /* CONFIG_DELAY_IDLE_SLEEP */
4588 		/* upon  successful spawn, re/set the proc control state */
4589 		if (imgp->ip_px_sa != NULL) {
4590 			switch (px_sa.psa_pcontrol) {
4591 			case POSIX_SPAWN_PCONTROL_THROTTLE:
4592 				p->p_pcaction = P_PCTHROTTLE;
4593 				break;
4594 			case POSIX_SPAWN_PCONTROL_SUSPEND:
4595 				p->p_pcaction = P_PCSUSP;
4596 				break;
4597 			case POSIX_SPAWN_PCONTROL_KILL:
4598 				p->p_pcaction = P_PCKILL;
4599 				break;
4600 			case POSIX_SPAWN_PCONTROL_NONE:
4601 			default:
4602 				p->p_pcaction = 0;
4603 				break;
4604 			}
4605 			;
4606 		}
4607 		exec_resettextvp(p, imgp);
4608 
4609 		vm_map_setup(get_task_map(new_task), new_task);
4610 
4611 		exec_setup_platform_restrictions(new_task);
4612 
4613 		/*
4614 		 * Set starting EXC_GUARD behavior for task now that platform
4615 		 * and platform restrictions bits are set.
4616 		 */
4617 		task_set_exc_guard_default(new_task,
4618 		    proc_best_name(p),
4619 		    strlen(proc_best_name(p)),
4620 		    proc_is_simulated(p),
4621 		    proc_platform(p),
4622 		    proc_sdk(p));
4623 
4624 		/*
4625 		 * Enable new task IPC access if exec_activate_image() returned an
4626 		 * active task. (Checks active bit in ipc_task_enable() under lock).
4627 		 * Must enable after resettextvp so that task port policies are not evaluated
4628 		 * until the csblob in the textvp is accurately reflected.
4629 		 */
4630 		ipc_task_enable(new_task);
4631 
4632 		/* Set task exception ports now that we can check entitlements */
4633 		if (imgp->ip_px_spa != NULL) {
4634 			error = exec_handle_exception_port_actions(imgp, &port_actions);
4635 		}
4636 
4637 #if CONFIG_MEMORYSTATUS
4638 		/* Set jetsam priority for DriverKit processes */
4639 		if (px_sa.psa_apptype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
4640 			px_sa.psa_priority = JETSAM_PRIORITY_DRIVER_APPLE;
4641 		}
4642 
4643 		/* Has jetsam attributes? */
4644 		if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_SET)) {
4645 			int32_t memlimit_active = px_sa.psa_memlimit_active;
4646 			int32_t memlimit_inactive = px_sa.psa_memlimit_inactive;
4647 
4648 			memstat_priority_options_t priority_options = MEMSTAT_PRIORITY_OPTIONS_NONE;
4649 			if ((px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY)) {
4650 				priority_options |= MEMSTAT_PRIORITY_IS_EFFECTIVE;
4651 			}
4652 			memorystatus_set_priority(p, px_sa.psa_priority, 0,
4653 			    priority_options);
4654 
4655 			memlimit_options_t memlimit_options = MEMLIMIT_OPTIONS_NONE;
4656 			if ((px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_ACTIVE_FATAL)) {
4657 				memlimit_options |= MEMLIMIT_ACTIVE_FATAL;
4658 			}
4659 			if ((px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_INACTIVE_FATAL)) {
4660 				memlimit_options |= MEMLIMIT_INACTIVE_FATAL;
4661 			}
4662 			if (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND) {
4663 				/*
4664 				 * With 2-level high-water-mark support,
4665 				 * POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is no longer relevant,
4666 				 * as background limits are described via the inactive limit
4667 				 * slots. However, if the
4668 				 * POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is passed in, we
4669 				 * attempt to mimic previous behavior by forcing the BG limit
4670 				 * data into the inactive/non-fatal mode and force the active
4671 				 * slots to hold system_wide/fatal mode.
4672 				 */
4673 				memlimit_options |= MEMLIMIT_ACTIVE_FATAL;
4674 				memlimit_options &= ~MEMLIMIT_INACTIVE_FATAL;
4675 				memlimit_active = -1;
4676 			}
4677 			memorystatus_set_memlimits(p, memlimit_active, memlimit_inactive,
4678 			    memlimit_options);
4679 		}
4680 
4681 		/* Has jetsam relaunch behavior? */
4682 		if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK)) {
4683 			/*
4684 			 * Launchd has passed in data indicating the behavior of this process in response to jetsam.
4685 			 * This data would be used by the jetsam subsystem to determine the position and protection
4686 			 * offered to this process on dirty -> clean transitions.
4687 			 */
4688 			int relaunch_flags = P_MEMSTAT_RELAUNCH_UNKNOWN;
4689 			switch (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK) {
4690 			case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_LOW:
4691 				relaunch_flags = P_MEMSTAT_RELAUNCH_LOW;
4692 				break;
4693 			case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MED:
4694 				relaunch_flags = P_MEMSTAT_RELAUNCH_MED;
4695 				break;
4696 			case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_HIGH:
4697 				relaunch_flags = P_MEMSTAT_RELAUNCH_HIGH;
4698 				break;
4699 			default:
4700 				break;
4701 			}
4702 			memorystatus_relaunch_flags_update(p, relaunch_flags);
4703 		}
4704 
4705 #endif /* CONFIG_MEMORYSTATUS */
4706 		if (imgp->ip_px_sa != NULL && px_sa.psa_thread_limit > 0) {
4707 			task_set_thread_limit(new_task, (uint16_t)px_sa.psa_thread_limit);
4708 		}
4709 		if (imgp->ip_px_sa != NULL && px_sa.psa_conclave_mem_limit > 0) {
4710 			task_set_conclave_mem_limit(new_task, px_sa.psa_conclave_mem_limit);
4711 		}
4712 
4713 #if CONFIG_PROC_RESOURCE_LIMITS
4714 		if (imgp->ip_px_sa != NULL && (px_sa.psa_port_soft_limit > 0 || px_sa.psa_port_hard_limit > 0)) {
4715 			task_set_port_space_limits(new_task, (uint32_t)px_sa.psa_port_soft_limit,
4716 			    (uint32_t)px_sa.psa_port_hard_limit);
4717 		}
4718 
4719 		if (imgp->ip_px_sa != NULL && (px_sa.psa_filedesc_soft_limit > 0 || px_sa.psa_filedesc_hard_limit > 0)) {
4720 			proc_set_filedesc_limits(p, (int)px_sa.psa_filedesc_soft_limit,
4721 			    (int)px_sa.psa_filedesc_hard_limit);
4722 		}
4723 		if (imgp->ip_px_sa != NULL && (px_sa.psa_kqworkloop_soft_limit > 0 || px_sa.psa_kqworkloop_hard_limit > 0)) {
4724 			proc_set_kqworkloop_limits(p, (int)px_sa.psa_kqworkloop_soft_limit,
4725 			    (int)px_sa.psa_kqworkloop_hard_limit);
4726 		}
4727 #endif /* CONFIG_PROC_RESOURCE_LIMITS */
4728 
4729 		if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_REALTIME_AUDIO)) {
4730 			task_set_jetsam_realtime_audio(new_task, TRUE);
4731 		}
4732 	}
4733 
4734 
4735 	/*
4736 	 * If we successfully called fork1() or cloneproc, we always need
4737 	 * to do this. This is because we come back from that call with
4738 	 * signals blocked in the child, and we have to unblock them, for exec
4739 	 * case they are unblocked before activation, but for true spawn case
4740 	 * we want to wait until after we've performed any spawn actions.
4741 	 * This has to happen before process_signature(), which uses psignal.
4742 	 */
4743 	if (proc_transit_set) {
4744 		proc_transend(p, 0);
4745 	}
4746 
4747 	/*
4748 	 * Drop the signal lock on the child which was taken on our
4749 	 * behalf by forkproc()/cloneproc() to prevent signals being
4750 	 * received by the child in a partially constructed state.
4751 	 */
4752 	if (proc_signal_set) {
4753 		proc_signalend(p, 0);
4754 	}
4755 
4756 	if (error == 0) {
4757 		/*
4758 		 * We need to initialize the bank context behind the protection of
4759 		 * the proc_trans lock to prevent a race with exit. We can't do this during
4760 		 * exec_activate_image because task_bank_init checks entitlements that
4761 		 * aren't loaded until subsequent calls (including exec_resettextvp).
4762 		 */
4763 		error = proc_transstart(p, 0, 0);
4764 
4765 		if (error == 0) {
4766 			task_bank_init(new_task);
4767 			proc_transend(p, 0);
4768 		}
4769 
4770 #if __arm64__
4771 		proc_footprint_entitlement_hacks(p, new_task);
4772 #endif /* __arm64__ */
4773 
4774 #if XNU_TARGET_OS_OSX
4775 #define SINGLE_JIT_ENTITLEMENT "com.apple.security.cs.single-jit"
4776 		if (IOTaskHasEntitlement(new_task, SINGLE_JIT_ENTITLEMENT)) {
4777 			vm_map_single_jit(get_task_map(new_task));
4778 		}
4779 #endif /* XNU_TARGET_OS_OSX */
4780 
4781 #if __has_feature(ptrauth_calls)
4782 		task_set_pac_exception_fatal_flag(new_task);
4783 #endif /* __has_feature(ptrauth_calls) */
4784 		task_set_jit_flags(new_task);
4785 	}
4786 
4787 	/* Inherit task role from old task to new task for exec */
4788 	if (error == 0 && !spawn_no_exec) {
4789 		proc_inherit_task_role(new_task, old_task);
4790 	}
4791 
4792 #if CONFIG_ARCADE
4793 	if (error == 0) {
4794 		/*
4795 		 * Check to see if we need to trigger an arcade upcall AST now
4796 		 * that the vnode has been reset on the task.
4797 		 */
4798 		arcade_prepare(new_task, imgp->ip_new_thread);
4799 	}
4800 #endif /* CONFIG_ARCADE */
4801 
4802 	if (error == 0) {
4803 		proc_apply_jit_and_vm_policies(imgp, p, new_task);
4804 	}
4805 
4806 	/* Clear the initial wait on the thread before handling spawn policy */
4807 	if (imgp && imgp->ip_new_thread) {
4808 		task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
4809 	}
4810 
4811 	/*
4812 	 * Apply the spawnattr policy, apptype (which primes the task for importance donation),
4813 	 * and bind any portwatch ports to the new task.
4814 	 * This must be done after the exec so that the child's thread is ready,
4815 	 * and after the in transit state has been released, because priority is
4816 	 * dropped here so we need to be prepared for a potentially long preemption interval
4817 	 *
4818 	 * TODO: Consider splitting this up into separate phases
4819 	 */
4820 	if (error == 0 && imgp->ip_px_sa != NULL) {
4821 		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4822 
4823 		error = exec_handle_spawnattr_policy(p, imgp->ip_new_thread, psa->psa_apptype, psa->psa_qos_clamp,
4824 		    psa->psa_darwin_role, &port_actions);
4825 	}
4826 
4827 	/* Transfer the turnstile watchport boost to new task if in exec */
4828 	if (error == 0 && !spawn_no_exec) {
4829 		task_transfer_turnstile_watchports(old_task, new_task, imgp->ip_new_thread);
4830 	}
4831 
4832 	if (error == 0 && imgp->ip_px_sa != NULL) {
4833 		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4834 
4835 		if (psa->psa_no_smt) {
4836 			task_set_no_smt(new_task);
4837 		}
4838 		if (psa->psa_tecs) {
4839 			task_set_tecs(new_task);
4840 		}
4841 	}
4842 
4843 	if (error == 0 && imgp->ip_px_sa != NULL) {
4844 		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4845 
4846 		if (psa->psa_options & PSA_OPTION_DATALESS_IOPOLICY) {
4847 			struct _iopol_param_t iop_param = {
4848 				.iop_scope = IOPOL_SCOPE_PROCESS,
4849 				.iop_iotype = IOPOL_TYPE_VFS_MATERIALIZE_DATALESS_FILES,
4850 				.iop_policy = psa->psa_dataless_iopolicy,
4851 			};
4852 			error = iopolicysys_vfs_materialize_dataless_files(p, IOPOL_CMD_SET, iop_param.iop_scope,
4853 			    iop_param.iop_policy, &iop_param);
4854 		}
4855 	}
4856 
4857 	if (error == 0) {
4858 		/* Apply the main thread qos */
4859 		thread_t main_thread = imgp->ip_new_thread;
4860 		task_set_main_thread_qos(new_task, main_thread);
4861 	}
4862 
4863 	/*
4864 	 * Release any ports we kept around for binding to the new task
4865 	 * We need to release the rights even if the posix_spawn has failed.
4866 	 */
4867 	if (imgp->ip_px_spa != NULL) {
4868 		exec_port_actions_destroy(&port_actions);
4869 	}
4870 
4871 	/*
4872 	 * We have to delay operations which might throw a signal until after
4873 	 * the signals have been unblocked; however, we want that to happen
4874 	 * after exec_resettextvp() so that the textvp is correct when they
4875 	 * fire.
4876 	 */
4877 	if (error == 0) {
4878 		error = process_signature(p, imgp);
4879 
4880 		/*
4881 		 * Pay for our earlier safety; deliver the delayed signals from
4882 		 * the incomplete spawn process now that it's complete.
4883 		 */
4884 		if (imgp != NULL && spawn_no_exec && (p->p_lflag & P_LTRACED)) {
4885 			psignal_vfork(p, proc_task(p), imgp->ip_new_thread, SIGTRAP);
4886 		}
4887 
4888 		if (error == 0 && !spawn_no_exec) {
4889 			extern uint64_t kdp_task_exec_meta_flags(task_t task);
4890 			KDBG(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXEC),
4891 			    proc_getpid(p), kdp_task_exec_meta_flags(proc_task(p)));
4892 		}
4893 	}
4894 
4895 	if (spawn_no_exec) {
4896 		/* flag the 'fork' has occurred */
4897 		proc_knote(p->p_pptr, NOTE_FORK | proc_getpid(p));
4898 	}
4899 
4900 	/* flag exec has occurred, notify only if it has not failed due to FP Key error */
4901 	if (!error && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
4902 		proc_knote(p, NOTE_EXEC);
4903 	}
4904 
4905 	if (imgp != NULL) {
4906 		uthread_set_exec_data(current_uthread(), NULL);
4907 		if (imgp->ip_vp) {
4908 			vnode_put(imgp->ip_vp);
4909 		}
4910 		if (imgp->ip_scriptvp) {
4911 			vnode_put(imgp->ip_scriptvp);
4912 		}
4913 		if (imgp->ip_strings) {
4914 			execargs_free(imgp);
4915 		}
4916 		if (imgp->ip_free_map) {
4917 			/* Free the map after dropping iocount on vnode to avoid deadlock */
4918 			vm_map_deallocate(imgp->ip_free_map);
4919 		}
4920 		kfree_data(imgp->ip_px_sfa,
4921 		    px_args.file_actions_size);
4922 		kfree_data(imgp->ip_px_spa,
4923 		    px_args.port_actions_size);
4924 #if CONFIG_PERSONAS
4925 		kfree_data(imgp->ip_px_persona,
4926 		    px_args.persona_info_size);
4927 #endif
4928 		kfree_data(imgp->ip_px_pcred_info,
4929 		    px_args.posix_cred_info_size);
4930 
4931 		if (subsystem_root_path != NULL) {
4932 			zfree(ZV_NAMEI, subsystem_root_path);
4933 		}
4934 #if CONFIG_MACF
4935 		struct ip_px_smpx_s *px_s = &imgp->ip_px_smpx;
4936 		kfree_data(px_s->array, px_args.mac_extensions_size);
4937 		kfree_data(px_s->data, (vm_size_t)px_s->datalen);
4938 
4939 		if (imgp->ip_execlabelp) {
4940 			mac_cred_label_free(imgp->ip_execlabelp);
4941 			imgp->ip_execlabelp = NULL;
4942 		}
4943 		if (imgp->ip_scriptlabelp) {
4944 			mac_vnode_label_free(imgp->ip_scriptlabelp);
4945 			imgp->ip_scriptlabelp = NULL;
4946 		}
4947 		if (imgp->ip_cs_error != OS_REASON_NULL) {
4948 			os_reason_free(imgp->ip_cs_error);
4949 			imgp->ip_cs_error = OS_REASON_NULL;
4950 		}
4951 		if (imgp->ip_inherited_shared_region_id != NULL) {
4952 			kfree_data(imgp->ip_inherited_shared_region_id,
4953 			    strlen(imgp->ip_inherited_shared_region_id) + 1);
4954 			imgp->ip_inherited_shared_region_id = NULL;
4955 		}
4956 #endif
4957 	}
4958 
4959 #if CONFIG_DTRACE
4960 	if (spawn_no_exec) {
4961 		/*
4962 		 * In the original DTrace reference implementation,
4963 		 * posix_spawn() was a libc routine that just
4964 		 * did vfork(2) then exec(2).  Thus the proc::: probes
4965 		 * are very fork/exec oriented.  The details of this
4966 		 * in-kernel implementation of posix_spawn() is different
4967 		 * (while producing the same process-observable effects)
4968 		 * particularly w.r.t. errors, and which thread/process
4969 		 * is constructing what on behalf of whom.
4970 		 */
4971 		if (error) {
4972 			DTRACE_PROC1(spawn__failure, int, error);
4973 		} else {
4974 			DTRACE_PROC(spawn__success);
4975 			/*
4976 			 * Some DTrace scripts, e.g. newproc.d in
4977 			 * /usr/bin, rely on the the 'exec-success'
4978 			 * probe being fired in the child after the
4979 			 * new process image has been constructed
4980 			 * in order to determine the associated pid.
4981 			 *
4982 			 * So, even though the parent built the image
4983 			 * here, for compatibility, mark the new thread
4984 			 * so 'exec-success' fires on it as it leaves
4985 			 * the kernel.
4986 			 */
4987 			dtrace_thread_didexec(imgp->ip_new_thread);
4988 		}
4989 	} else {
4990 		if (error) {
4991 			DTRACE_PROC1(exec__failure, int, error);
4992 		} else {
4993 			dtrace_thread_didexec(imgp->ip_new_thread);
4994 		}
4995 	}
4996 
4997 	if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
4998 		(*dtrace_proc_waitfor_hook)(p);
4999 	}
5000 #endif
5001 
5002 #if CONFIG_AUDIT
5003 	if (!error && AUDIT_ENABLED() && p) {
5004 		/* Add the CDHash of the new process to the audit record */
5005 		uint8_t *cdhash = cs_get_cdhash(p);
5006 		if (cdhash) {
5007 			AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
5008 		}
5009 	}
5010 #endif
5011 
5012 	/* terminate the new task if exec failed  */
5013 	if (new_task != NULL && task_is_exec_copy(new_task)) {
5014 		task_terminate_internal(new_task);
5015 	}
5016 
5017 	if (exec_failure_reason && !spawn_no_exec) {
5018 		psignal_with_reason(p, SIGKILL, exec_failure_reason);
5019 		exec_failure_reason = NULL;
5020 	}
5021 
5022 	/* Return to both the parent and the child? */
5023 	if (imgp != NULL && spawn_no_exec) {
5024 		/*
5025 		 * If the parent wants the pid, copy it out
5026 		 */
5027 		if (error == 0 && pid != USER_ADDR_NULL) {
5028 			_Static_assert(sizeof(pid_t) == 4, "posix_spawn() assumes a 32-bit pid_t");
5029 			bool aligned = (pid & 3) == 0;
5030 			if (aligned) {
5031 				(void)copyout_atomic32(proc_getpid(p), pid);
5032 			} else {
5033 				(void)suword(pid, proc_getpid(p));
5034 			}
5035 		}
5036 		retval[0] = error;
5037 
5038 		/*
5039 		 * If we had an error, perform an internal reap ; this is
5040 		 * entirely safe, as we have a real process backing us.
5041 		 */
5042 		if (error) {
5043 			proc_list_lock();
5044 			p->p_listflag |= P_LIST_DEADPARENT;
5045 			proc_list_unlock();
5046 			proc_lock(p);
5047 			/* make sure no one else has killed it off... */
5048 			if (p->p_stat != SZOMB && p->exit_thread == NULL) {
5049 				p->exit_thread = current_thread();
5050 				p->p_posix_spawn_failed = true;
5051 				proc_unlock(p);
5052 				exit1(p, 1, (int *)NULL);
5053 			} else {
5054 				/* someone is doing it for us; just skip it */
5055 				proc_unlock(p);
5056 			}
5057 		}
5058 	}
5059 
5060 	/*
5061 	 * Do not terminate the current task, if proc_exec_switch_task did not
5062 	 * switch the tasks, terminating the current task without the switch would
5063 	 * result in loosing the SIGKILL status.
5064 	 */
5065 	if (task_did_exec(old_task)) {
5066 		/* Terminate the current task, since exec will start in new task */
5067 		task_terminate_internal(old_task);
5068 	}
5069 
5070 	/* Release the thread ref returned by cloneproc/fork1 */
5071 	if (imgp != NULL && imgp->ip_new_thread) {
5072 		/* clear the exec complete flag if there is an error before point of no-return */
5073 		uint32_t clearwait_flags = TCRW_CLEAR_FINAL_WAIT;
5074 		if (!spawn_no_exec && !exec_done && error != 0) {
5075 			clearwait_flags |= TCRW_CLEAR_EXEC_COMPLETE;
5076 		}
5077 		/* wake up the new thread */
5078 		task_clear_return_wait(get_threadtask(imgp->ip_new_thread), clearwait_flags);
5079 		thread_deallocate(imgp->ip_new_thread);
5080 		imgp->ip_new_thread = NULL;
5081 	}
5082 
5083 	/* Release the ref returned by cloneproc/fork1 */
5084 	if (new_task) {
5085 		task_deallocate(new_task);
5086 		new_task = NULL;
5087 	}
5088 
5089 	if (should_release_proc_ref) {
5090 		proc_rele(p);
5091 	}
5092 
5093 	kfree_type(typeof(*__spawn_data), __spawn_data);
5094 
5095 	if (inherit != NULL) {
5096 		ipc_importance_release(inherit);
5097 	}
5098 
5099 #if CONFIG_EXCLAVES
5100 	if (task_conclave_id != NULL) {
5101 		kfree_data(task_conclave_id, MAXCONCLAVENAME);
5102 	}
5103 #endif
5104 
5105 	assert(spawn_no_exec || exec_failure_reason == NULL);
5106 	return error;
5107 }
5108 
5109 /*
5110  * proc_exec_switch_task
5111  *
5112  * Parameters:  old_proc		proc before exec
5113  *		new_proc		proc after exec
5114  *		old_task		task before exec
5115  *		new_task		task after exec
5116  *		imgp			image params
5117  *		inherit			resulting importance linkage
5118  *
5119  * Returns: proc.
5120  *
5121  * Note: The function will switch proc in pid hash from old proc to new proc.
5122  * The switch needs to happen after draining all proc refs and inside
5123  * a proc list lock. In the case of failure to switch the proc, which
5124  * might happen if the process received a SIGKILL or jetsam killed it,
5125  * it will make sure that the new tasks terminates. User proc ref returned
5126  * to caller.
5127  *
5128  * This function is called after point of no return, in the case
5129  * failure to switch, it will terminate the new task and swallow the
5130  * error and let the terminated process complete exec and die.
5131  */
5132 proc_t
proc_exec_switch_task(proc_t old_proc,proc_t new_proc,task_t old_task,task_t new_task,struct image_params * imgp,void ** inherit)5133 proc_exec_switch_task(proc_t old_proc, proc_t new_proc, task_t old_task, task_t new_task, struct image_params *imgp, void **inherit)
5134 {
5135 	boolean_t task_active;
5136 	boolean_t proc_active;
5137 	boolean_t thread_active;
5138 	boolean_t reparent_traced_child = FALSE;
5139 	thread_t old_thread = current_thread();
5140 	thread_t new_thread = imgp->ip_new_thread;
5141 
5142 	thread_set_exec_promotion(old_thread);
5143 	old_proc = proc_refdrain_will_exec(old_proc);
5144 
5145 	new_proc = proc_refdrain_will_exec(new_proc);
5146 	/* extra proc ref returned to the caller */
5147 
5148 	assert(get_threadtask(new_thread) == new_task);
5149 	task_active = task_is_active(new_task);
5150 	proc_active = !(old_proc->p_lflag & P_LEXIT);
5151 
5152 	/* Check if the current thread is not aborted due to SIGKILL */
5153 	thread_active = thread_is_active(old_thread);
5154 
5155 	/*
5156 	 * Do not switch the proc if the new task or proc is already terminated
5157 	 * as a result of error in exec past point of no return
5158 	 */
5159 	if (proc_active && task_active && thread_active) {
5160 		uthread_t new_uthread = get_bsdthread_info(new_thread);
5161 		uthread_t old_uthread = current_uthread();
5162 
5163 		/* Clear dispatchqueue and workloop ast offset */
5164 		new_proc->p_dispatchqueue_offset = 0;
5165 		new_proc->p_dispatchqueue_serialno_offset = 0;
5166 		new_proc->p_dispatchqueue_label_offset = 0;
5167 		new_proc->p_return_to_kernel_offset = 0;
5168 		new_proc->p_pthread_wq_quantum_offset = 0;
5169 
5170 		/* If old_proc is session leader, change the leader to new proc */
5171 		session_replace_leader(old_proc, new_proc);
5172 
5173 		proc_lock(old_proc);
5174 
5175 		/* Copy the signal state, dtrace state and set bsd ast on new thread */
5176 		act_set_astbsd(new_thread);
5177 		new_uthread->uu_siglist |= old_uthread->uu_siglist;
5178 		new_uthread->uu_siglist |= old_proc->p_siglist;
5179 		new_uthread->uu_sigwait = old_uthread->uu_sigwait;
5180 		new_uthread->uu_sigmask = old_uthread->uu_sigmask;
5181 		new_uthread->uu_oldmask = old_uthread->uu_oldmask;
5182 		new_uthread->uu_exit_reason = old_uthread->uu_exit_reason;
5183 #if CONFIG_DTRACE
5184 		new_uthread->t_dtrace_sig = old_uthread->t_dtrace_sig;
5185 		new_uthread->t_dtrace_stop = old_uthread->t_dtrace_stop;
5186 		new_uthread->t_dtrace_resumepid = old_uthread->t_dtrace_resumepid;
5187 		assert(new_uthread->t_dtrace_scratch == NULL);
5188 		new_uthread->t_dtrace_scratch = old_uthread->t_dtrace_scratch;
5189 
5190 		old_uthread->t_dtrace_sig = 0;
5191 		old_uthread->t_dtrace_stop = 0;
5192 		old_uthread->t_dtrace_resumepid = 0;
5193 		old_uthread->t_dtrace_scratch = NULL;
5194 #endif
5195 
5196 #if CONFIG_PROC_UDATA_STORAGE
5197 		new_proc->p_user_data = old_proc->p_user_data;
5198 #endif /* CONFIG_PROC_UDATA_STORAGE */
5199 
5200 		/* Copy the resource accounting info */
5201 		thread_copy_resource_info(new_thread, current_thread());
5202 
5203 		/* Clear the exit reason and signal state on old thread */
5204 		old_uthread->uu_exit_reason = NULL;
5205 		old_uthread->uu_siglist = 0;
5206 
5207 		task_set_did_exec_flag(old_task);
5208 		task_clear_exec_copy_flag(new_task);
5209 
5210 		task_copy_fields_for_exec(new_task, old_task);
5211 
5212 		/*
5213 		 * Need to transfer pending watch port boosts to the new task
5214 		 * while still making sure that the old task remains in the
5215 		 * importance linkage. Create an importance linkage from old task
5216 		 * to new task, then switch the task importance base of old task
5217 		 * and new task. After the switch the port watch boost will be
5218 		 * boosting the new task and new task will be donating importance
5219 		 * to old task.
5220 		 */
5221 		*inherit = ipc_importance_exec_switch_task(old_task, new_task);
5222 
5223 		/* Transfer parent's ptrace state to child */
5224 		new_proc->p_lflag &= ~(P_LTRACED | P_LSIGEXC | P_LNOATTACH);
5225 		new_proc->p_lflag |= (old_proc->p_lflag & (P_LTRACED | P_LSIGEXC | P_LNOATTACH));
5226 		new_proc->p_oppid = old_proc->p_oppid;
5227 
5228 		if (old_proc->p_pptr != new_proc->p_pptr) {
5229 			reparent_traced_child = TRUE;
5230 			new_proc->p_lflag |= P_LTRACE_WAIT;
5231 		}
5232 
5233 		proc_unlock(old_proc);
5234 
5235 		/* Update the list of proc knotes */
5236 		proc_transfer_knotes(old_proc, new_proc);
5237 
5238 		/* Update the proc interval timers */
5239 		proc_inherit_itimers(old_proc, new_proc);
5240 
5241 		proc_list_lock();
5242 
5243 		/* Insert the new proc in child list of parent proc */
5244 		p_reparentallchildren(old_proc, new_proc);
5245 
5246 		/* Switch proc in pid hash */
5247 		phash_replace_locked(old_proc, new_proc);
5248 
5249 		/* Transfer the shadow flag to old proc */
5250 		os_atomic_andnot(&new_proc->p_refcount, P_REF_SHADOW, relaxed);
5251 		os_atomic_or(&old_proc->p_refcount, P_REF_SHADOW, relaxed);
5252 
5253 		/* Change init proc if launchd exec */
5254 		if (old_proc == initproc) {
5255 			/* Take the ref on new proc after proc_refwake_did_exec */
5256 			initproc = new_proc;
5257 			/* Drop the proc ref on old proc */
5258 			proc_rele(old_proc);
5259 		}
5260 
5261 		proc_list_unlock();
5262 #if CONFIG_EXCLAVES
5263 		if (task_inherit_conclave(old_task, new_task, imgp->ip_vp,
5264 		    (int64_t)imgp->ip_arch_offset) != KERN_SUCCESS) {
5265 			task_terminate_internal(new_task);
5266 		}
5267 #endif
5268 	} else {
5269 		task_terminate_internal(new_task);
5270 	}
5271 
5272 	proc_refwake_did_exec(new_proc);
5273 	proc_refwake_did_exec(old_proc);
5274 
5275 	/* Take a ref on initproc if it changed */
5276 	if (new_proc == initproc) {
5277 		initproc = proc_ref(new_proc, false);
5278 		assert(initproc != PROC_NULL);
5279 	}
5280 
5281 	thread_clear_exec_promotion(old_thread);
5282 	proc_rele(old_proc);
5283 
5284 	if (reparent_traced_child) {
5285 		proc_t pp = proc_parent(old_proc);
5286 		assert(pp != PROC_NULL);
5287 
5288 		proc_reparentlocked(new_proc, pp, 1, 0);
5289 		proc_rele(pp);
5290 
5291 		proc_lock(new_proc);
5292 		new_proc->p_lflag &= ~P_LTRACE_WAIT;
5293 		proc_unlock(new_proc);
5294 	}
5295 
5296 	return new_proc;
5297 }
5298 
5299 /*
5300  * execve
5301  *
5302  * Parameters:	uap->fname		File name to exec
5303  *		uap->argp		Argument list
5304  *		uap->envp		Environment list
5305  *
5306  * Returns:	0			Success
5307  *	__mac_execve:EINVAL		Invalid argument
5308  *	__mac_execve:ENOTSUP		Invalid argument
5309  *	__mac_execve:EACCES		Permission denied
5310  *	__mac_execve:EINTR		Interrupted function
5311  *	__mac_execve:ENOMEM		Not enough space
5312  *	__mac_execve:EFAULT		Bad address
5313  *	__mac_execve:ENAMETOOLONG	Filename too long
5314  *	__mac_execve:ENOEXEC		Executable file format error
5315  *	__mac_execve:ETXTBSY		Text file busy [misuse of error code]
5316  *	__mac_execve:???
5317  *
5318  * TODO:	Dynamic linker header address on stack is copied via suword()
5319  */
5320 /* ARGSUSED */
5321 int
execve(proc_t p,struct execve_args * uap,int32_t * retval)5322 execve(proc_t p, struct execve_args *uap, int32_t *retval)
5323 {
5324 	struct __mac_execve_args muap;
5325 	int err;
5326 
5327 	memoryshot(DBG_VM_EXECVE, DBG_FUNC_NONE);
5328 
5329 	muap.fname = uap->fname;
5330 	muap.argp = uap->argp;
5331 	muap.envp = uap->envp;
5332 	muap.mac_p = USER_ADDR_NULL;
5333 	err = __mac_execve(p, &muap, retval);
5334 
5335 	return err;
5336 }
5337 
5338 /*
5339  * __mac_execve
5340  *
5341  * Parameters:	uap->fname		File name to exec
5342  *		uap->argp		Argument list
5343  *		uap->envp		Environment list
5344  *		uap->mac_p		MAC label supplied by caller
5345  *
5346  * Returns:	0			Success
5347  *		EINVAL			Invalid argument
5348  *		ENOTSUP			Not supported
5349  *		ENOEXEC			Executable file format error
5350  *	exec_activate_image:EINVAL	Invalid argument
5351  *	exec_activate_image:EACCES	Permission denied
5352  *	exec_activate_image:EINTR	Interrupted function
5353  *	exec_activate_image:ENOMEM	Not enough space
5354  *	exec_activate_image:EFAULT	Bad address
5355  *	exec_activate_image:ENAMETOOLONG	Filename too long
5356  *	exec_activate_image:ENOEXEC	Executable file format error
5357  *	exec_activate_image:ETXTBSY	Text file busy [misuse of error code]
5358  *	exec_activate_image:EBADEXEC	The executable is corrupt/unknown
5359  *	exec_activate_image:???
5360  *	mac_execve_enter:???
5361  *
5362  * TODO:	Dynamic linker header address on stack is copied via suword()
5363  */
5364 int
__mac_execve(proc_t p,struct __mac_execve_args * uap,int32_t * retval __unused)5365 __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval __unused)
5366 {
5367 	struct image_params *imgp = NULL;
5368 	struct vnode_attr *vap = NULL;
5369 	struct vnode_attr *origvap = NULL;
5370 	int error;
5371 	int is_64 = IS_64BIT_PROCESS(p);
5372 	struct vfs_context context;
5373 	struct uthread  *uthread = NULL;
5374 	task_t old_task = current_task();
5375 	task_t new_task = NULL;
5376 	boolean_t should_release_proc_ref = FALSE;
5377 	boolean_t exec_done = FALSE;
5378 	void *inherit = NULL;
5379 	struct {
5380 		struct image_params imgp;
5381 		struct vnode_attr va;
5382 		struct vnode_attr origva;
5383 	} *__execve_data;
5384 
5385 	/* Allocate a big chunk for locals instead of using stack since these
5386 	 * structures are pretty big.
5387 	 */
5388 	__execve_data = kalloc_type(typeof(*__execve_data), Z_WAITOK | Z_ZERO);
5389 	if (__execve_data == NULL) {
5390 		error = ENOMEM;
5391 		goto exit_with_error;
5392 	}
5393 	imgp = &__execve_data->imgp;
5394 	vap = &__execve_data->va;
5395 	origvap = &__execve_data->origva;
5396 
5397 	/* Initialize the common data in the image_params structure */
5398 	imgp->ip_user_fname = uap->fname;
5399 	imgp->ip_user_argv = uap->argp;
5400 	imgp->ip_user_envv = uap->envp;
5401 	imgp->ip_vattr = vap;
5402 	imgp->ip_origvattr = origvap;
5403 	imgp->ip_vfs_context = &context;
5404 	imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE) | ((p->p_flag & P_DISABLE_ASLR) ? IMGPF_DISABLE_ASLR : IMGPF_NONE);
5405 	imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
5406 	imgp->ip_mac_return = 0;
5407 	imgp->ip_cs_error = OS_REASON_NULL;
5408 	imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
5409 	imgp->ip_subsystem_root_path = NULL;
5410 	uthread_set_exec_data(current_uthread(), imgp);
5411 
5412 #if CONFIG_MACF
5413 	if (uap->mac_p != USER_ADDR_NULL) {
5414 		error = mac_execve_enter(uap->mac_p, imgp);
5415 		if (error) {
5416 			goto exit_with_error;
5417 		}
5418 	}
5419 #endif
5420 	uthread = current_uthread();
5421 	{
5422 		imgp->ip_flags |= IMGPF_EXEC;
5423 
5424 		/* Adjust the user proc count */
5425 		(void)chgproccnt(kauth_getruid(), 1);
5426 		/*
5427 		 * For execve case, create a new proc, task and thread
5428 		 * but don't make the proc visible to userland. After
5429 		 * image activation, the new proc would take place of
5430 		 * the old proc in pid hash and other lists that make
5431 		 * the proc visible to the system.
5432 		 */
5433 		imgp->ip_new_thread = cloneproc(old_task, NULL, p, CLONEPROC_EXEC);
5434 		/* task and thread ref returned by cloneproc */
5435 		if (imgp->ip_new_thread == NULL) {
5436 			(void)chgproccnt(kauth_getruid(), -1);
5437 			error = ENOMEM;
5438 			goto exit_with_error;
5439 		}
5440 
5441 		new_task = get_threadtask(imgp->ip_new_thread);
5442 	}
5443 
5444 
5445 	p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
5446 
5447 	context.vc_thread = imgp->ip_new_thread;
5448 	context.vc_ucred = kauth_cred_proc_ref(p);      /* XXX must NOT be kauth_cred_get() */
5449 
5450 	imgp->ip_subsystem_root_path = p->p_subsystem_root_path;
5451 
5452 	proc_transend(p, 0);
5453 	proc_signalend(p, 0);
5454 
5455 	/*
5456 	 * Activate the image.
5457 	 * Warning: If activation failed after point of no return, it returns error
5458 	 * as 0 and pretends the call succeeded.
5459 	 */
5460 	error = exec_activate_image(imgp);
5461 	/* thread and task ref returned for vfexec case */
5462 
5463 	if (imgp->ip_new_thread != NULL) {
5464 		/*
5465 		 * task reference might be returned by exec_activate_image
5466 		 * for vfexec.
5467 		 */
5468 		new_task = get_threadtask(imgp->ip_new_thread);
5469 #if defined(HAS_APPLE_PAC)
5470 		ml_task_set_disable_user_jop(new_task, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
5471 		ml_thread_set_disable_user_jop(imgp->ip_new_thread, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
5472 #endif
5473 	}
5474 
5475 	if (!error) {
5476 		p = proc_exec_switch_task(current_proc(), p, old_task, new_task, imgp, &inherit);
5477 		/* proc ref returned */
5478 		should_release_proc_ref = TRUE;
5479 	}
5480 
5481 	kauth_cred_unref(&context.vc_ucred);
5482 
5483 	if (!error) {
5484 		exec_done = TRUE;
5485 		assert(imgp->ip_new_thread != NULL);
5486 
5487 		exec_resettextvp(p, imgp);
5488 
5489 		vm_map_setup(get_task_map(new_task), new_task);
5490 
5491 		exec_setup_platform_restrictions(new_task);
5492 
5493 		/*
5494 		 * Set starting EXC_GUARD behavior for task now that platform
5495 		 * and platform restrictions bits are set.
5496 		 */
5497 		task_set_exc_guard_default(new_task,
5498 		    proc_best_name(p),
5499 		    strlen(proc_best_name(p)),
5500 		    proc_is_simulated(p),
5501 		    proc_platform(p),
5502 		    proc_sdk(p));
5503 
5504 		/*
5505 		 * Enable new task IPC access if exec_activate_image() returned an
5506 		 * active task. (Checks active bit in ipc_task_enable() under lock).
5507 		 * Must enable after resettextvp so that task port policies are not evaluated
5508 		 * until the csblob in the textvp is accurately reflected.
5509 		 */
5510 		ipc_task_enable(new_task);
5511 		error = process_signature(p, imgp);
5512 	}
5513 
5514 
5515 #if defined(HAS_APPLE_PAC)
5516 	if (imgp->ip_new_thread && !error) {
5517 		ml_task_set_jop_pid_from_shared_region(new_task, imgp->ip_flags & IMGPF_NOJOP);
5518 		ml_thread_set_jop_pid(imgp->ip_new_thread, new_task);
5519 	}
5520 #endif /* defined(HAS_APPLE_PAC) */
5521 
5522 	/* flag exec has occurred, notify only if it has not failed due to FP Key error */
5523 	if (exec_done && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
5524 		proc_knote(p, NOTE_EXEC);
5525 	}
5526 
5527 	if (imgp->ip_vp != NULLVP) {
5528 		vnode_put(imgp->ip_vp);
5529 	}
5530 	if (imgp->ip_scriptvp != NULLVP) {
5531 		vnode_put(imgp->ip_scriptvp);
5532 	}
5533 	if (imgp->ip_free_map) {
5534 		/* Free the map after dropping iocount on vnode to avoid deadlock */
5535 		vm_map_deallocate(imgp->ip_free_map);
5536 	}
5537 	if (imgp->ip_strings) {
5538 		execargs_free(imgp);
5539 	}
5540 #if CONFIG_MACF
5541 	if (imgp->ip_execlabelp) {
5542 		mac_cred_label_free(imgp->ip_execlabelp);
5543 		imgp->ip_execlabelp = NULL;
5544 	}
5545 	if (imgp->ip_scriptlabelp) {
5546 		mac_vnode_label_free(imgp->ip_scriptlabelp);
5547 		imgp->ip_scriptlabelp = NULL;
5548 	}
5549 #endif
5550 	if (imgp->ip_cs_error != OS_REASON_NULL) {
5551 		os_reason_free(imgp->ip_cs_error);
5552 		imgp->ip_cs_error = OS_REASON_NULL;
5553 	}
5554 
5555 	if (!error) {
5556 		/*
5557 		 * We need to initialize the bank context behind the protection of
5558 		 * the proc_trans lock to prevent a race with exit. We can't do this during
5559 		 * exec_activate_image because task_bank_init checks entitlements that
5560 		 * aren't loaded until subsequent calls (including exec_resettextvp).
5561 		 */
5562 		error = proc_transstart(p, 0, 0);
5563 	}
5564 
5565 	if (!error) {
5566 		task_bank_init(new_task);
5567 		proc_transend(p, 0);
5568 
5569 		// Don't inherit crash behavior across exec, but preserve crash behavior from bootargs
5570 		p->p_crash_behavior = 0;
5571 		p->p_crash_behavior_deadline = 0;
5572 #if (DEVELOPMENT || DEBUG)
5573 		set_crash_behavior_from_bootarg(p);
5574 #endif
5575 
5576 #if __arm64__
5577 		proc_footprint_entitlement_hacks(p, new_task);
5578 #endif /* __arm64__ */
5579 
5580 #if XNU_TARGET_OS_OSX
5581 		if (IOTaskHasEntitlement(new_task, SINGLE_JIT_ENTITLEMENT)) {
5582 			vm_map_single_jit(get_task_map(new_task));
5583 		}
5584 #endif /* XNU_TARGET_OS_OSX */
5585 
5586 		/* Sever any extant thread affinity */
5587 		thread_affinity_exec(current_thread());
5588 
5589 		/* Inherit task role from old task to new task for exec */
5590 		proc_inherit_task_role(new_task, old_task);
5591 
5592 		thread_t main_thread = imgp->ip_new_thread;
5593 
5594 		task_set_main_thread_qos(new_task, main_thread);
5595 
5596 #if __has_feature(ptrauth_calls)
5597 		task_set_pac_exception_fatal_flag(new_task);
5598 #endif /* __has_feature(ptrauth_calls) */
5599 		task_set_jit_flags(new_task);
5600 
5601 #if CONFIG_ARCADE
5602 		/*
5603 		 * Check to see if we need to trigger an arcade upcall AST now
5604 		 * that the vnode has been reset on the task.
5605 		 */
5606 		arcade_prepare(new_task, imgp->ip_new_thread);
5607 #endif /* CONFIG_ARCADE */
5608 
5609 		proc_apply_jit_and_vm_policies(imgp, p, new_task);
5610 
5611 		if (vm_darkwake_mode == TRUE) {
5612 			/*
5613 			 * This process is being launched when the system
5614 			 * is in darkwake. So mark it specially. This will
5615 			 * cause all its pages to be entered in the background Q.
5616 			 */
5617 			task_set_darkwake_mode(new_task, vm_darkwake_mode);
5618 		}
5619 
5620 #if CONFIG_DTRACE
5621 		dtrace_thread_didexec(imgp->ip_new_thread);
5622 
5623 		if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
5624 			(*dtrace_proc_waitfor_hook)(p);
5625 		}
5626 #endif
5627 
5628 #if CONFIG_AUDIT
5629 		if (!error && AUDIT_ENABLED() && p) {
5630 			/* Add the CDHash of the new process to the audit record */
5631 			uint8_t *cdhash = cs_get_cdhash(p);
5632 			if (cdhash) {
5633 				AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
5634 			}
5635 		}
5636 #endif
5637 	} else {
5638 		DTRACE_PROC1(exec__failure, int, error);
5639 	}
5640 
5641 exit_with_error:
5642 
5643 	/* terminate the new task it if exec failed  */
5644 	if (new_task != NULL && task_is_exec_copy(new_task)) {
5645 		task_terminate_internal(new_task);
5646 	}
5647 
5648 	if (imgp != NULL) {
5649 		/* Clear the initial wait on the thread transferring watchports */
5650 		if (imgp->ip_new_thread) {
5651 			task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
5652 		}
5653 
5654 		/* Transfer the watchport boost to new task */
5655 		if (!error) {
5656 			task_transfer_turnstile_watchports(old_task,
5657 			    new_task, imgp->ip_new_thread);
5658 		}
5659 		/*
5660 		 * Do not terminate the current task, if proc_exec_switch_task did not
5661 		 * switch the tasks, terminating the current task without the switch would
5662 		 * result in loosing the SIGKILL status.
5663 		 */
5664 		if (task_did_exec(old_task)) {
5665 			/* Terminate the current task, since exec will start in new task */
5666 			task_terminate_internal(old_task);
5667 		}
5668 
5669 		/* Release the thread ref returned by cloneproc */
5670 		if (imgp->ip_new_thread) {
5671 			/* clear the exec complete flag if there is an error before point of no-return */
5672 			uint32_t clearwait_flags = TCRW_CLEAR_FINAL_WAIT;
5673 			if (!exec_done && error != 0) {
5674 				clearwait_flags |= TCRW_CLEAR_EXEC_COMPLETE;
5675 			}
5676 			/* wake up the new exec thread */
5677 			task_clear_return_wait(get_threadtask(imgp->ip_new_thread), clearwait_flags);
5678 			thread_deallocate(imgp->ip_new_thread);
5679 			imgp->ip_new_thread = NULL;
5680 		}
5681 	}
5682 
5683 	/* Release the ref returned by fork_create_child */
5684 	if (new_task) {
5685 		task_deallocate(new_task);
5686 		new_task = NULL;
5687 	}
5688 
5689 	if (should_release_proc_ref) {
5690 		proc_rele(p);
5691 	}
5692 
5693 	uthread_set_exec_data(current_uthread(), NULL);
5694 	kfree_type(typeof(*__execve_data), __execve_data);
5695 
5696 	if (inherit != NULL) {
5697 		ipc_importance_release(inherit);
5698 	}
5699 
5700 	return error;
5701 }
5702 
5703 
5704 /*
5705  * copyinptr
5706  *
5707  * Description:	Copy a pointer in from user space to a user_addr_t in kernel
5708  *		space, based on 32/64 bitness of the user space
5709  *
5710  * Parameters:	froma			User space address
5711  *		toptr			Address of kernel space user_addr_t
5712  *		ptr_size		4/8, based on 'froma' address space
5713  *
5714  * Returns:	0			Success
5715  *		EFAULT			Bad 'froma'
5716  *
5717  * Implicit returns:
5718  *		*ptr_size		Modified
5719  */
5720 static int
copyinptr(user_addr_t froma,user_addr_t * toptr,int ptr_size)5721 copyinptr(user_addr_t froma, user_addr_t *toptr, int ptr_size)
5722 {
5723 	int error;
5724 
5725 	if (ptr_size == 4) {
5726 		/* 64 bit value containing 32 bit address */
5727 		unsigned int i = 0;
5728 
5729 		error = copyin(froma, &i, 4);
5730 		*toptr = CAST_USER_ADDR_T(i);   /* SAFE */
5731 	} else {
5732 		error = copyin(froma, toptr, 8);
5733 	}
5734 	return error;
5735 }
5736 
5737 
5738 /*
5739  * copyoutptr
5740  *
5741  * Description:	Copy a pointer out from a user_addr_t in kernel space to
5742  *		user space, based on 32/64 bitness of the user space
5743  *
5744  * Parameters:	ua			User space address to copy to
5745  *		ptr			Address of kernel space user_addr_t
5746  *		ptr_size		4/8, based on 'ua' address space
5747  *
5748  * Returns:	0			Success
5749  *		EFAULT			Bad 'ua'
5750  *
5751  */
5752 static int
copyoutptr(user_addr_t ua,user_addr_t ptr,int ptr_size)5753 copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size)
5754 {
5755 	int error;
5756 
5757 	if (ptr_size == 4) {
5758 		/* 64 bit value containing 32 bit address */
5759 		unsigned int i = CAST_DOWN_EXPLICIT(unsigned int, ua);   /* SAFE */
5760 
5761 		error = copyout(&i, ptr, 4);
5762 	} else {
5763 		error = copyout(&ua, ptr, 8);
5764 	}
5765 	return error;
5766 }
5767 
5768 
5769 /*
5770  * exec_copyout_strings
5771  *
5772  * Copy out the strings segment to user space.  The strings segment is put
5773  * on a preinitialized stack frame.
5774  *
5775  * Parameters:	struct image_params *	the image parameter block
5776  *		int *			a pointer to the stack offset variable
5777  *
5778  * Returns:	0			Success
5779  *		!0			Faiure: errno
5780  *
5781  * Implicit returns:
5782  *		(*stackp)		The stack offset, modified
5783  *
5784  * Note:	The strings segment layout is backward, from the beginning
5785  *		of the top of the stack to consume the minimal amount of
5786  *		space possible; the returned stack pointer points to the
5787  *		end of the area consumed (stacks grow downward).
5788  *
5789  *		argc is an int; arg[i] are pointers; env[i] are pointers;
5790  *		the 0's are (void *)NULL's
5791  *
5792  * The stack frame layout is:
5793  *
5794  *      +-------------+ <- p->user_stack
5795  *      |     16b     |
5796  *      +-------------+
5797  *      | STRING AREA |
5798  *      |      :      |
5799  *      |      :      |
5800  *      |      :      |
5801  *      +- -- -- -- --+
5802  *      |  PATH AREA  |
5803  *      +-------------+
5804  *      |      0      |
5805  *      +-------------+
5806  *      |  applev[n]  |
5807  *      +-------------+
5808  *             :
5809  *             :
5810  *      +-------------+
5811  *      |  applev[1]  |
5812  *      +-------------+
5813  *      | exec_path / |
5814  *      |  applev[0]  |
5815  *      +-------------+
5816  *      |      0      |
5817  *      +-------------+
5818  *      |    env[n]   |
5819  *      +-------------+
5820  *             :
5821  *             :
5822  *      +-------------+
5823  *      |    env[0]   |
5824  *      +-------------+
5825  *      |      0      |
5826  *      +-------------+
5827  *      | arg[argc-1] |
5828  *      +-------------+
5829  *             :
5830  *             :
5831  *      +-------------+
5832  *      |    arg[0]   |
5833  *      +-------------+
5834  *      |     argc    |
5835  * sp-> +-------------+
5836  *
5837  * Although technically a part of the STRING AREA, we treat the PATH AREA as
5838  * a separate entity.  This allows us to align the beginning of the PATH AREA
5839  * to a pointer boundary so that the exec_path, env[i], and argv[i] pointers
5840  * which preceed it on the stack are properly aligned.
5841  */
5842 __attribute__((noinline))
5843 static int
exec_copyout_strings(struct image_params * imgp,user_addr_t * stackp)5844 exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp)
5845 {
5846 	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
5847 	int     ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
5848 	int     ptr_area_size;
5849 	void *ptr_buffer_start, *ptr_buffer;
5850 	size_t string_size;
5851 
5852 	user_addr_t     string_area;    /* *argv[], *env[] */
5853 	user_addr_t     ptr_area;       /* argv[], env[], applev[] */
5854 	user_addr_t argc_area;  /* argc */
5855 	user_addr_t     stack;
5856 	int error;
5857 
5858 	unsigned i;
5859 	struct copyout_desc {
5860 		char    *start_string;
5861 		int             count;
5862 #if CONFIG_DTRACE
5863 		user_addr_t     *dtrace_cookie;
5864 #endif
5865 		boolean_t       null_term;
5866 	} descriptors[] = {
5867 		{
5868 			.start_string = imgp->ip_startargv,
5869 			.count = imgp->ip_argc,
5870 #if CONFIG_DTRACE
5871 			.dtrace_cookie = &p->p_dtrace_argv,
5872 #endif
5873 			.null_term = TRUE
5874 		},
5875 		{
5876 			.start_string = imgp->ip_endargv,
5877 			.count = imgp->ip_envc,
5878 #if CONFIG_DTRACE
5879 			.dtrace_cookie = &p->p_dtrace_envp,
5880 #endif
5881 			.null_term = TRUE
5882 		},
5883 		{
5884 			.start_string = imgp->ip_strings,
5885 			.count = 1,
5886 #if CONFIG_DTRACE
5887 			.dtrace_cookie = NULL,
5888 #endif
5889 			.null_term = FALSE
5890 		},
5891 		{
5892 			.start_string = imgp->ip_endenvv,
5893 			.count = imgp->ip_applec - 1, /* exec_path handled above */
5894 #if CONFIG_DTRACE
5895 			.dtrace_cookie = NULL,
5896 #endif
5897 			.null_term = TRUE
5898 		}
5899 	};
5900 
5901 	stack = *stackp;
5902 
5903 	/*
5904 	 * All previous contributors to the string area
5905 	 * should have aligned their sub-area
5906 	 */
5907 	if (imgp->ip_strspace % ptr_size != 0) {
5908 		error = EINVAL;
5909 		goto bad;
5910 	}
5911 
5912 	/* Grow the stack down for the strings we've been building up */
5913 	string_size = imgp->ip_strendp - imgp->ip_strings;
5914 	stack -= string_size;
5915 	string_area = stack;
5916 
5917 	/*
5918 	 * Need room for one pointer for each string, plus
5919 	 * one for the NULLs terminating the argv, envv, and apple areas.
5920 	 */
5921 	ptr_area_size = (imgp->ip_argc + imgp->ip_envc + imgp->ip_applec + 3) * ptr_size;
5922 	stack -= ptr_area_size;
5923 	ptr_area = stack;
5924 
5925 	/* We'll construct all the pointer arrays in our string buffer,
5926 	 * which we already know is aligned properly, and ip_argspace
5927 	 * was used to verify we have enough space.
5928 	 */
5929 	ptr_buffer_start = ptr_buffer = (void *)imgp->ip_strendp;
5930 
5931 	/*
5932 	 * Need room for pointer-aligned argc slot.
5933 	 */
5934 	stack -= ptr_size;
5935 	argc_area = stack;
5936 
5937 	/*
5938 	 * Record the size of the arguments area so that sysctl_procargs()
5939 	 * can return the argument area without having to parse the arguments.
5940 	 */
5941 	proc_lock(p);
5942 	p->p_argc = imgp->ip_argc;
5943 	p->p_argslen = (int)(*stackp - string_area);
5944 	proc_unlock(p);
5945 
5946 	/* Return the initial stack address: the location of argc */
5947 	*stackp = stack;
5948 
5949 	/*
5950 	 * Copy out the entire strings area.
5951 	 */
5952 	error = copyout(imgp->ip_strings, string_area,
5953 	    string_size);
5954 	if (error) {
5955 		goto bad;
5956 	}
5957 
5958 	for (i = 0; i < sizeof(descriptors) / sizeof(descriptors[0]); i++) {
5959 		char *cur_string = descriptors[i].start_string;
5960 		int j;
5961 
5962 #if CONFIG_DTRACE
5963 		if (descriptors[i].dtrace_cookie) {
5964 			proc_lock(p);
5965 			*descriptors[i].dtrace_cookie = ptr_area + ((uintptr_t)ptr_buffer - (uintptr_t)ptr_buffer_start); /* dtrace convenience */
5966 			proc_unlock(p);
5967 		}
5968 #endif /* CONFIG_DTRACE */
5969 
5970 		/*
5971 		 * For each segment (argv, envv, applev), copy as many pointers as requested
5972 		 * to our pointer buffer.
5973 		 */
5974 		for (j = 0; j < descriptors[i].count; j++) {
5975 			user_addr_t cur_address = string_area + (cur_string - imgp->ip_strings);
5976 
5977 			/* Copy out the pointer to the current string. Alignment has been verified  */
5978 			if (ptr_size == 8) {
5979 				*(uint64_t *)ptr_buffer = (uint64_t)cur_address;
5980 			} else {
5981 				*(uint32_t *)ptr_buffer = (uint32_t)cur_address;
5982 			}
5983 
5984 			ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
5985 			cur_string += strlen(cur_string) + 1; /* Only a NUL between strings in the same area */
5986 		}
5987 
5988 		if (descriptors[i].null_term) {
5989 			if (ptr_size == 8) {
5990 				*(uint64_t *)ptr_buffer = 0ULL;
5991 			} else {
5992 				*(uint32_t *)ptr_buffer = 0;
5993 			}
5994 
5995 			ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
5996 		}
5997 	}
5998 
5999 	/*
6000 	 * Copy out all our pointer arrays in bulk.
6001 	 */
6002 	error = copyout(ptr_buffer_start, ptr_area,
6003 	    ptr_area_size);
6004 	if (error) {
6005 		goto bad;
6006 	}
6007 
6008 	/* argc (int32, stored in a ptr_size area) */
6009 	error = copyoutptr((user_addr_t)imgp->ip_argc, argc_area, ptr_size);
6010 	if (error) {
6011 		goto bad;
6012 	}
6013 
6014 bad:
6015 	return error;
6016 }
6017 
6018 
6019 /*
6020  * exec_extract_strings
6021  *
6022  * Copy arguments and environment from user space into work area; we may
6023  * have already copied some early arguments into the work area, and if
6024  * so, any arguments opied in are appended to those already there.
6025  * This function is the primary manipulator of ip_argspace, since
6026  * these are the arguments the client of execve(2) knows about. After
6027  * each argv[]/envv[] string is copied, we charge the string length
6028  * and argv[]/envv[] pointer slot to ip_argspace, so that we can
6029  * full preflight the arg list size.
6030  *
6031  * Parameters:	struct image_params *	the image parameter block
6032  *
6033  * Returns:	0			Success
6034  *		!0			Failure: errno
6035  *
6036  * Implicit returns;
6037  *		(imgp->ip_argc)		Count of arguments, updated
6038  *		(imgp->ip_envc)		Count of environment strings, updated
6039  *		(imgp->ip_argspace)	Count of remaining of NCARGS
6040  *		(imgp->ip_interp_buffer)	Interpreter and args (mutated in place)
6041  *
6042  *
6043  * Note:	The argument and environment vectors are user space pointers
6044  *		to arrays of user space pointers.
6045  */
6046 __attribute__((noinline))
6047 static int
exec_extract_strings(struct image_params * imgp)6048 exec_extract_strings(struct image_params *imgp)
6049 {
6050 	int error = 0;
6051 	int     ptr_size = (imgp->ip_flags & IMGPF_WAS_64BIT_ADDR) ? 8 : 4;
6052 	int new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
6053 	user_addr_t     argv = imgp->ip_user_argv;
6054 	user_addr_t     envv = imgp->ip_user_envv;
6055 
6056 	/*
6057 	 * Adjust space reserved for the path name by however much padding it
6058 	 * needs. Doing this here since we didn't know if this would be a 32-
6059 	 * or 64-bit process back in exec_save_path.
6060 	 */
6061 	while (imgp->ip_strspace % new_ptr_size != 0) {
6062 		*imgp->ip_strendp++ = '\0';
6063 		imgp->ip_strspace--;
6064 		/* imgp->ip_argspace--; not counted towards exec args total */
6065 	}
6066 
6067 	/*
6068 	 * From now on, we start attributing string space to ip_argspace
6069 	 */
6070 	imgp->ip_startargv = imgp->ip_strendp;
6071 	imgp->ip_argc = 0;
6072 
6073 	if ((imgp->ip_flags & IMGPF_INTERPRET) != 0) {
6074 		user_addr_t     arg;
6075 		char *argstart, *ch;
6076 
6077 		/* First, the arguments in the "#!" string are tokenized and extracted. */
6078 		argstart = imgp->ip_interp_buffer;
6079 		while (argstart) {
6080 			ch = argstart;
6081 			while (*ch && !IS_WHITESPACE(*ch)) {
6082 				ch++;
6083 			}
6084 
6085 			if (*ch == '\0') {
6086 				/* last argument, no need to NUL-terminate */
6087 				error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
6088 				argstart = NULL;
6089 			} else {
6090 				/* NUL-terminate */
6091 				*ch = '\0';
6092 				error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
6093 
6094 				/*
6095 				 * Find the next string. We know spaces at the end of the string have already
6096 				 * been stripped.
6097 				 */
6098 				argstart = ch + 1;
6099 				while (IS_WHITESPACE(*argstart)) {
6100 					argstart++;
6101 				}
6102 			}
6103 
6104 			/* Error-check, regardless of whether this is the last interpreter arg or not */
6105 			if (error) {
6106 				goto bad;
6107 			}
6108 			if (imgp->ip_argspace < new_ptr_size) {
6109 				error = E2BIG;
6110 				goto bad;
6111 			}
6112 			imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
6113 			imgp->ip_argc++;
6114 		}
6115 
6116 		if (argv != 0LL) {
6117 			/*
6118 			 * If we are running an interpreter, replace the av[0] that was
6119 			 * passed to execve() with the path name that was
6120 			 * passed to execve() for interpreters which do not use the PATH
6121 			 * to locate their script arguments.
6122 			 */
6123 			error = copyinptr(argv, &arg, ptr_size);
6124 			if (error) {
6125 				goto bad;
6126 			}
6127 			if (arg != 0LL) {
6128 				argv += ptr_size; /* consume without using */
6129 			}
6130 		}
6131 
6132 		if (imgp->ip_interp_sugid_fd != -1) {
6133 			char temp[19]; /* "/dev/fd/" + 10 digits + NUL */
6134 			snprintf(temp, sizeof(temp), "/dev/fd/%d", imgp->ip_interp_sugid_fd);
6135 			error = exec_add_user_string(imgp, CAST_USER_ADDR_T(temp), UIO_SYSSPACE, TRUE);
6136 		} else {
6137 			error = exec_add_user_string(imgp, imgp->ip_user_fname, imgp->ip_seg, TRUE);
6138 		}
6139 
6140 		if (error) {
6141 			goto bad;
6142 		}
6143 		if (imgp->ip_argspace < new_ptr_size) {
6144 			error = E2BIG;
6145 			goto bad;
6146 		}
6147 		imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
6148 		imgp->ip_argc++;
6149 	}
6150 
6151 	while (argv != 0LL) {
6152 		user_addr_t     arg;
6153 
6154 		error = copyinptr(argv, &arg, ptr_size);
6155 		if (error) {
6156 			goto bad;
6157 		}
6158 
6159 		if (arg == 0LL) {
6160 			break;
6161 		}
6162 
6163 		argv += ptr_size;
6164 
6165 		/*
6166 		 * av[n...] = arg[n]
6167 		 */
6168 		error = exec_add_user_string(imgp, arg, imgp->ip_seg, TRUE);
6169 		if (error) {
6170 			goto bad;
6171 		}
6172 		if (imgp->ip_argspace < new_ptr_size) {
6173 			error = E2BIG;
6174 			goto bad;
6175 		}
6176 		imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
6177 		imgp->ip_argc++;
6178 	}
6179 
6180 	/* Save space for argv[] NULL terminator */
6181 	if (imgp->ip_argspace < new_ptr_size) {
6182 		error = E2BIG;
6183 		goto bad;
6184 	}
6185 	imgp->ip_argspace -= new_ptr_size;
6186 
6187 	/* Note where the args ends and env begins. */
6188 	imgp->ip_endargv = imgp->ip_strendp;
6189 	imgp->ip_envc = 0;
6190 
6191 	/* Now, get the environment */
6192 	while (envv != 0LL) {
6193 		user_addr_t     env;
6194 
6195 		error = copyinptr(envv, &env, ptr_size);
6196 		if (error) {
6197 			goto bad;
6198 		}
6199 
6200 		envv += ptr_size;
6201 		if (env == 0LL) {
6202 			break;
6203 		}
6204 		/*
6205 		 * av[n...] = env[n]
6206 		 */
6207 		error = exec_add_user_string(imgp, env, imgp->ip_seg, TRUE);
6208 		if (error) {
6209 			goto bad;
6210 		}
6211 		if (imgp->ip_argspace < new_ptr_size) {
6212 			error = E2BIG;
6213 			goto bad;
6214 		}
6215 		imgp->ip_argspace -= new_ptr_size; /* to hold envv[] entry */
6216 		imgp->ip_envc++;
6217 	}
6218 
6219 	/* Save space for envv[] NULL terminator */
6220 	if (imgp->ip_argspace < new_ptr_size) {
6221 		error = E2BIG;
6222 		goto bad;
6223 	}
6224 	imgp->ip_argspace -= new_ptr_size;
6225 
6226 	/* Align the tail of the combined argv+envv area */
6227 	while (imgp->ip_strspace % new_ptr_size != 0) {
6228 		if (imgp->ip_argspace < 1) {
6229 			error = E2BIG;
6230 			goto bad;
6231 		}
6232 		*imgp->ip_strendp++ = '\0';
6233 		imgp->ip_strspace--;
6234 		imgp->ip_argspace--;
6235 	}
6236 
6237 	/* Note where the envv ends and applev begins. */
6238 	imgp->ip_endenvv = imgp->ip_strendp;
6239 
6240 	/*
6241 	 * From now on, we are no longer charging argument
6242 	 * space to ip_argspace.
6243 	 */
6244 
6245 bad:
6246 	return error;
6247 }
6248 
6249 /*
6250  * Libc has an 8-element array set up for stack guard values.  It only fills
6251  * in one of those entries, and both gcc and llvm seem to use only a single
6252  * 8-byte guard.  Until somebody needs more than an 8-byte guard value, don't
6253  * do the work to construct them.
6254  */
6255 #define GUARD_VALUES 1
6256 #define GUARD_KEY "stack_guard="
6257 
6258 /*
6259  * System malloc needs some entropy when it is initialized.
6260  */
6261 #define ENTROPY_VALUES 2
6262 #define ENTROPY_KEY "malloc_entropy="
6263 
6264 /*
6265  * libplatform needs a random pointer-obfuscation value when it is initialized.
6266  */
6267 #define PTR_MUNGE_VALUES 1
6268 #define PTR_MUNGE_KEY "ptr_munge="
6269 
6270 /*
6271  * System malloc engages nanozone for UIAPP.
6272  */
6273 #define NANO_ENGAGE_KEY "MallocNanoZone=1"
6274 
6275 /*
6276  * Used to pass experiment flags up to libmalloc.
6277  */
6278 #define LIBMALLOC_EXPERIMENT_FACTORS_KEY "MallocExperiment="
6279 
6280 /*
6281  * Passes information about hardened heap/"hardened runtime" entitlements to libsystem/libmalloc
6282  */
6283 #define HARDENED_RUNTIME_KEY "HardenedRuntime="
6284 
6285 #define PFZ_KEY "pfz="
6286 extern user32_addr_t commpage_text32_location;
6287 extern user64_addr_t commpage_text64_location;
6288 
6289 extern uuid_string_t bootsessionuuid_string;
6290 static TUNABLE(uint32_t, exe_boothash_salt, "exe_boothash_salt", 0);
6291 
6292 __startup_func
6293 static void
exe_boothash_salt_generate(void)6294 exe_boothash_salt_generate(void)
6295 {
6296 	if (!PE_parse_boot_argn("exe_boothash_salt", NULL, 0)) {
6297 		read_random(&exe_boothash_salt, sizeof(exe_boothash_salt));
6298 	}
6299 }
6300 STARTUP(EARLY_BOOT, STARTUP_RANK_MIDDLE, exe_boothash_salt_generate);
6301 
6302 
6303 #define MAIN_STACK_VALUES 4
6304 #define MAIN_STACK_KEY "main_stack="
6305 
6306 #define FSID_KEY "executable_file="
6307 #define DYLD_FSID_KEY "dyld_file="
6308 #define CDHASH_KEY "executable_cdhash="
6309 #define DYLD_FLAGS_KEY "dyld_flags="
6310 #define SUBSYSTEM_ROOT_PATH_KEY "subsystem_root_path="
6311 #define APP_BOOT_SESSION_KEY "executable_boothash="
6312 #if __has_feature(ptrauth_calls)
6313 #define PTRAUTH_DISABLED_FLAG "ptrauth_disabled=1"
6314 #define DYLD_ARM64E_ABI_KEY "arm64e_abi="
6315 #endif /* __has_feature(ptrauth_calls) */
6316 #define MAIN_TH_PORT_KEY "th_port="
6317 
6318 #define FSID_MAX_STRING "0x1234567890abcdef,0x1234567890abcdef"
6319 
6320 #define HEX_STR_LEN 18 // 64-bit hex value "0x0123456701234567"
6321 #define HEX_STR_LEN32 10 // 32-bit hex value "0x01234567"
6322 
6323 #if XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES
6324 #define VM_FORCE_4K_PAGES_KEY "vm_force_4k_pages=1"
6325 #endif /* XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES */
6326 
6327 static int
exec_add_entropy_key(struct image_params * imgp,const char * key,int values,boolean_t embedNUL)6328 exec_add_entropy_key(struct image_params *imgp,
6329     const char *key,
6330     int values,
6331     boolean_t embedNUL)
6332 {
6333 	const int limit = 8;
6334 	uint64_t entropy[limit];
6335 	char str[strlen(key) + (HEX_STR_LEN + 1) * limit + 1];
6336 	if (values > limit) {
6337 		values = limit;
6338 	}
6339 
6340 	read_random(entropy, sizeof(entropy[0]) * values);
6341 
6342 	if (embedNUL) {
6343 		entropy[0] &= ~(0xffull << 8);
6344 	}
6345 
6346 	int len = scnprintf(str, sizeof(str), "%s0x%llx", key, entropy[0]);
6347 	size_t remaining = sizeof(str) - len;
6348 	for (int i = 1; i < values && remaining > 0; ++i) {
6349 		size_t start = sizeof(str) - remaining;
6350 		len = scnprintf(&str[start], remaining, ",0x%llx", entropy[i]);
6351 		remaining -= len;
6352 	}
6353 
6354 	return exec_add_user_string(imgp, CAST_USER_ADDR_T(str), UIO_SYSSPACE, FALSE);
6355 }
6356 
6357 /*
6358  * Build up the contents of the apple[] string vector
6359  */
6360 #if (DEVELOPMENT || DEBUG)
6361 extern uint64_t dyld_flags;
6362 #endif
6363 
6364 #if __has_feature(ptrauth_calls)
6365 static inline bool
is_arm64e_running_as_arm64(const struct image_params * imgp)6366 is_arm64e_running_as_arm64(const struct image_params *imgp)
6367 {
6368 	return (imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
6369 	       (imgp->ip_flags & IMGPF_NOJOP);
6370 }
6371 #endif /* __has_feature(ptrauth_calls) */
6372 
6373 _Atomic uint64_t libmalloc_experiment_factors = 0;
6374 
6375 static int
exec_add_apple_strings(struct image_params * imgp,const load_result_t * load_result,task_t task)6376 exec_add_apple_strings(struct image_params *imgp,
6377     const load_result_t *load_result, task_t task)
6378 {
6379 	int error;
6380 	int img_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
6381 	thread_t new_thread;
6382 	ipc_port_t sright;
6383 	uint64_t local_experiment_factors = 0;
6384 
6385 	/* exec_save_path stored the first string */
6386 	imgp->ip_applec = 1;
6387 
6388 	/* adding the pfz string */
6389 	{
6390 		char pfz_string[strlen(PFZ_KEY) + HEX_STR_LEN + 1];
6391 
6392 		if (img_ptr_size == 8) {
6393 			__assert_only size_t ret = snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%llx", commpage_text64_location);
6394 			assert(ret < sizeof(pfz_string));
6395 		} else {
6396 			snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%x", commpage_text32_location);
6397 		}
6398 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(pfz_string), UIO_SYSSPACE, FALSE);
6399 		if (error) {
6400 			printf("Failed to add the pfz string with error %d\n", error);
6401 			goto bad;
6402 		}
6403 		imgp->ip_applec++;
6404 	}
6405 
6406 	/* adding the NANO_ENGAGE_KEY key */
6407 	if (imgp->ip_px_sa) {
6408 		struct _posix_spawnattr* psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
6409 		int proc_flags = psa->psa_flags;
6410 
6411 		if ((proc_flags & _POSIX_SPAWN_NANO_ALLOCATOR) == _POSIX_SPAWN_NANO_ALLOCATOR) {
6412 			const char *nano_string = NANO_ENGAGE_KEY;
6413 			error = exec_add_user_string(imgp, CAST_USER_ADDR_T(nano_string), UIO_SYSSPACE, FALSE);
6414 			if (error) {
6415 				goto bad;
6416 			}
6417 			imgp->ip_applec++;
6418 		}
6419 	}
6420 
6421 	/*
6422 	 * Supply libc with a collection of random values to use when
6423 	 * implementing -fstack-protector.
6424 	 *
6425 	 * (The first random string always contains an embedded NUL so that
6426 	 * __stack_chk_guard also protects against C string vulnerabilities)
6427 	 */
6428 	error = exec_add_entropy_key(imgp, GUARD_KEY, GUARD_VALUES, TRUE);
6429 	if (error) {
6430 		goto bad;
6431 	}
6432 	imgp->ip_applec++;
6433 
6434 	/*
6435 	 * Supply libc with entropy for system malloc.
6436 	 */
6437 	error = exec_add_entropy_key(imgp, ENTROPY_KEY, ENTROPY_VALUES, FALSE);
6438 	if (error) {
6439 		goto bad;
6440 	}
6441 	imgp->ip_applec++;
6442 
6443 	/*
6444 	 * Supply libpthread & libplatform with a random value to use for pointer
6445 	 * obfuscation.
6446 	 */
6447 	error = exec_add_entropy_key(imgp, PTR_MUNGE_KEY, PTR_MUNGE_VALUES, FALSE);
6448 	if (error) {
6449 		goto bad;
6450 	}
6451 	imgp->ip_applec++;
6452 
6453 	/*
6454 	 * Add MAIN_STACK_KEY: Supplies the address and size of the main thread's
6455 	 * stack if it was allocated by the kernel.
6456 	 *
6457 	 * The guard page is not included in this stack size as libpthread
6458 	 * expects to add it back in after receiving this value.
6459 	 */
6460 	if (load_result->unixproc) {
6461 		char stack_string[strlen(MAIN_STACK_KEY) + (HEX_STR_LEN + 1) * MAIN_STACK_VALUES + 1];
6462 		snprintf(stack_string, sizeof(stack_string),
6463 		    MAIN_STACK_KEY "0x%llx,0x%llx,0x%llx,0x%llx",
6464 		    (uint64_t)load_result->user_stack,
6465 		    (uint64_t)load_result->user_stack_size,
6466 		    (uint64_t)load_result->user_stack_alloc,
6467 		    (uint64_t)load_result->user_stack_alloc_size);
6468 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(stack_string), UIO_SYSSPACE, FALSE);
6469 		if (error) {
6470 			goto bad;
6471 		}
6472 		imgp->ip_applec++;
6473 	}
6474 
6475 	if (imgp->ip_vattr) {
6476 		uint64_t fsid    = vnode_get_va_fsid(imgp->ip_vattr);
6477 		uint64_t fsobjid = imgp->ip_vattr->va_fileid;
6478 
6479 		char fsid_string[strlen(FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
6480 		snprintf(fsid_string, sizeof(fsid_string),
6481 		    FSID_KEY "0x%llx,0x%llx", fsid, fsobjid);
6482 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
6483 		if (error) {
6484 			goto bad;
6485 		}
6486 		imgp->ip_applec++;
6487 	}
6488 
6489 	if (imgp->ip_dyld_fsid || imgp->ip_dyld_fsobjid) {
6490 		char fsid_string[strlen(DYLD_FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
6491 		snprintf(fsid_string, sizeof(fsid_string),
6492 		    DYLD_FSID_KEY "0x%llx,0x%llx", imgp->ip_dyld_fsid, imgp->ip_dyld_fsobjid);
6493 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
6494 		if (error) {
6495 			goto bad;
6496 		}
6497 		imgp->ip_applec++;
6498 	}
6499 
6500 	uint8_t cdhash[SHA1_RESULTLEN];
6501 	int cdhash_errror = ubc_cs_getcdhash(imgp->ip_vp, imgp->ip_arch_offset, cdhash, NULL);
6502 	if (cdhash_errror == 0) {
6503 		char hash_string[strlen(CDHASH_KEY) + 2 * SHA1_RESULTLEN + 1];
6504 		strncpy(hash_string, CDHASH_KEY, sizeof(hash_string));
6505 		char *p = hash_string + sizeof(CDHASH_KEY) - 1;
6506 		for (int i = 0; i < SHA1_RESULTLEN; i++) {
6507 			snprintf(p, 3, "%02x", (int) cdhash[i]);
6508 			p += 2;
6509 		}
6510 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(hash_string), UIO_SYSSPACE, FALSE);
6511 		if (error) {
6512 			goto bad;
6513 		}
6514 		imgp->ip_applec++;
6515 
6516 		/* hash together cd-hash and boot-session-uuid */
6517 		uint8_t sha_digest[SHA256_DIGEST_LENGTH];
6518 		SHA256_CTX sha_ctx;
6519 		SHA256_Init(&sha_ctx);
6520 		SHA256_Update(&sha_ctx, &exe_boothash_salt, sizeof(exe_boothash_salt));
6521 		SHA256_Update(&sha_ctx, bootsessionuuid_string, sizeof(bootsessionuuid_string));
6522 		SHA256_Update(&sha_ctx, cdhash, sizeof(cdhash));
6523 		SHA256_Final(sha_digest, &sha_ctx);
6524 		char app_boot_string[strlen(APP_BOOT_SESSION_KEY) + 2 * SHA1_RESULTLEN + 1];
6525 		strncpy(app_boot_string, APP_BOOT_SESSION_KEY, sizeof(app_boot_string));
6526 		char *s = app_boot_string + sizeof(APP_BOOT_SESSION_KEY) - 1;
6527 		for (int i = 0; i < SHA1_RESULTLEN; i++) {
6528 			snprintf(s, 3, "%02x", (int) sha_digest[i]);
6529 			s += 2;
6530 		}
6531 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(app_boot_string), UIO_SYSSPACE, FALSE);
6532 		if (error) {
6533 			goto bad;
6534 		}
6535 		imgp->ip_applec++;
6536 	}
6537 #if (DEVELOPMENT || DEBUG)
6538 	if (dyld_flags) {
6539 		char dyld_flags_string[strlen(DYLD_FLAGS_KEY) + HEX_STR_LEN + 1];
6540 		snprintf(dyld_flags_string, sizeof(dyld_flags_string), DYLD_FLAGS_KEY "0x%llx", dyld_flags);
6541 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_flags_string), UIO_SYSSPACE, FALSE);
6542 		if (error) {
6543 			goto bad;
6544 		}
6545 		imgp->ip_applec++;
6546 	}
6547 #endif
6548 	if (imgp->ip_subsystem_root_path) {
6549 		size_t buffer_len = MAXPATHLEN + strlen(SUBSYSTEM_ROOT_PATH_KEY);
6550 		char subsystem_root_path_string[buffer_len];
6551 		int required_len = snprintf(subsystem_root_path_string, buffer_len, SUBSYSTEM_ROOT_PATH_KEY "%s", imgp->ip_subsystem_root_path);
6552 
6553 		if (((size_t)required_len >= buffer_len) || (required_len < 0)) {
6554 			error = ENAMETOOLONG;
6555 			goto bad;
6556 		}
6557 
6558 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(subsystem_root_path_string), UIO_SYSSPACE, FALSE);
6559 		if (error) {
6560 			goto bad;
6561 		}
6562 
6563 		imgp->ip_applec++;
6564 	}
6565 #if __has_feature(ptrauth_calls)
6566 	if (is_arm64e_running_as_arm64(imgp)) {
6567 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(PTRAUTH_DISABLED_FLAG), UIO_SYSSPACE, FALSE);
6568 		if (error) {
6569 			goto bad;
6570 		}
6571 
6572 		imgp->ip_applec++;
6573 	}
6574 #endif /* __has_feature(ptrauth_calls) */
6575 
6576 
6577 #if __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX)
6578 	{
6579 		char dyld_abi_string[strlen(DYLD_ARM64E_ABI_KEY) + 8];
6580 		strlcpy(dyld_abi_string, DYLD_ARM64E_ABI_KEY, sizeof(dyld_abi_string));
6581 		bool allowAll = bootarg_arm64e_preview_abi;
6582 		strlcat(dyld_abi_string, (allowAll ? "all" : "os"), sizeof(dyld_abi_string));
6583 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_abi_string), UIO_SYSSPACE, FALSE);
6584 		if (error) {
6585 			goto bad;
6586 		}
6587 
6588 		imgp->ip_applec++;
6589 	}
6590 #endif
6591 	/*
6592 	 * Add main thread mach port name
6593 	 * +1 uref on main thread port, this ref will be extracted by libpthread in __pthread_init
6594 	 * and consumed in _bsdthread_terminate. Leaking the main thread port name if not linked
6595 	 * against libpthread.
6596 	 */
6597 	if ((new_thread = imgp->ip_new_thread) != THREAD_NULL) {
6598 		thread_reference(new_thread);
6599 		sright = convert_thread_to_port_immovable(new_thread);
6600 		task_t new_task = get_threadtask(new_thread);
6601 		mach_port_name_t name = ipc_port_copyout_send_pinned(sright, get_task_ipcspace(new_task));
6602 		char port_name_hex_str[strlen(MAIN_TH_PORT_KEY) + HEX_STR_LEN32 + 1];
6603 		snprintf(port_name_hex_str, sizeof(port_name_hex_str), MAIN_TH_PORT_KEY "0x%x", name);
6604 
6605 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(port_name_hex_str), UIO_SYSSPACE, FALSE);
6606 		if (error) {
6607 			goto bad;
6608 		}
6609 		imgp->ip_applec++;
6610 	}
6611 
6612 #if XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES
6613 	if (imgp->ip_px_sa != NULL) {
6614 		struct _posix_spawnattr* psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
6615 		if (psa->psa_flags & _POSIX_SPAWN_FORCE_4K_PAGES) {
6616 			const char *vm_force_4k_string = VM_FORCE_4K_PAGES_KEY;
6617 			error = exec_add_user_string(imgp, CAST_USER_ADDR_T(vm_force_4k_string), UIO_SYSSPACE, FALSE);
6618 			if (error) {
6619 				goto bad;
6620 			}
6621 			imgp->ip_applec++;
6622 		}
6623 	}
6624 #endif /* XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES */
6625 
6626 	/* adding the libmalloc experiment string */
6627 	local_experiment_factors = os_atomic_load_wide(&libmalloc_experiment_factors, relaxed);
6628 	if (__improbable(local_experiment_factors != 0)) {
6629 		char libmalloc_experiment_factors_string[strlen(LIBMALLOC_EXPERIMENT_FACTORS_KEY) + HEX_STR_LEN + 1];
6630 
6631 		snprintf(
6632 			libmalloc_experiment_factors_string,
6633 			sizeof(libmalloc_experiment_factors_string),
6634 			LIBMALLOC_EXPERIMENT_FACTORS_KEY "0x%llx",
6635 			local_experiment_factors);
6636 		error = exec_add_user_string(
6637 			imgp,
6638 			CAST_USER_ADDR_T(libmalloc_experiment_factors_string),
6639 			UIO_SYSSPACE,
6640 			FALSE);
6641 		if (error) {
6642 			printf("Failed to add the libmalloc experiment factors string with error %d\n", error);
6643 			goto bad;
6644 		}
6645 		imgp->ip_applec++;
6646 	}
6647 
6648 	/*
6649 	 * Push down the task security configuration. To reduce confusion when userland parses the information
6650 	 * still push an empty security configuration if nothing is active.
6651 	 */
6652 	{
6653 		#define SECURITY_CONFIG_KEY "security_config="
6654 		char security_config_str[strlen(SECURITY_CONFIG_KEY) + HEX_STR_LEN + 1];
6655 
6656 		snprintf(security_config_str, sizeof(security_config_str),
6657 		    SECURITY_CONFIG_KEY "0x%x", task_get_security_config(task));
6658 
6659 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(security_config_str), UIO_SYSSPACE, FALSE);
6660 		if (error) {
6661 			printf("Failed to add the security config string with error %d\n", error);
6662 			goto bad;
6663 		}
6664 		imgp->ip_applec++;
6665 	}
6666 
6667 
6668 
6669 
6670 	if (load_result->hardened_browser) {
6671 		const size_t HR_STRING_SIZE = sizeof(HARDENED_RUNTIME_KEY) + HR_FLAGS_NUM_NIBBLES + 2 + 1;
6672 		char hardened_runtime[HR_STRING_SIZE];
6673 		snprintf(hardened_runtime, HR_STRING_SIZE, HARDENED_RUNTIME_KEY"0x%x", load_result->hardened_browser);
6674 		error = exec_add_user_string(imgp, CAST_USER_ADDR_T(hardened_runtime), UIO_SYSSPACE, FALSE);
6675 		if (error) {
6676 			printf("Failed to add hardened runtime flag with error %d\n", error);
6677 			goto bad;
6678 		}
6679 		imgp->ip_applec++;
6680 	}
6681 	/* Align the tail of the combined applev area */
6682 	while (imgp->ip_strspace % img_ptr_size != 0) {
6683 		*imgp->ip_strendp++ = '\0';
6684 		imgp->ip_strspace--;
6685 	}
6686 
6687 bad:
6688 	return error;
6689 }
6690 
6691 /*
6692  * exec_check_permissions
6693  *
6694  * Description:	Verify that the file that is being attempted to be executed
6695  *		is in fact allowed to be executed based on it POSIX file
6696  *		permissions and other access control criteria
6697  *
6698  * Parameters:	struct image_params *	the image parameter block
6699  *
6700  * Returns:	0			Success
6701  *		EACCES			Permission denied
6702  *		ENOEXEC			Executable file format error
6703  *		ETXTBSY			Text file busy [misuse of error code]
6704  *	vnode_getattr:???
6705  *	vnode_authorize:???
6706  */
6707 static int
exec_check_permissions(struct image_params * imgp)6708 exec_check_permissions(struct image_params *imgp)
6709 {
6710 	struct vnode *vp = imgp->ip_vp;
6711 	struct vnode_attr *vap = imgp->ip_vattr;
6712 	proc_t p = vfs_context_proc(imgp->ip_vfs_context);
6713 	int error;
6714 	kauth_action_t action;
6715 
6716 	/* Only allow execution of regular files */
6717 	if (!vnode_isreg(vp)) {
6718 		return EACCES;
6719 	}
6720 
6721 	/* Get the file attributes that we will be using here and elsewhere */
6722 	VATTR_INIT(vap);
6723 	VATTR_WANTED(vap, va_uid);
6724 	VATTR_WANTED(vap, va_gid);
6725 	VATTR_WANTED(vap, va_mode);
6726 	VATTR_WANTED(vap, va_fsid);
6727 	VATTR_WANTED(vap, va_fsid64);
6728 	VATTR_WANTED(vap, va_fileid);
6729 	VATTR_WANTED(vap, va_data_size);
6730 	if ((error = vnode_getattr(vp, vap, imgp->ip_vfs_context)) != 0) {
6731 		return error;
6732 	}
6733 
6734 	/*
6735 	 * Ensure that at least one execute bit is on - otherwise root
6736 	 * will always succeed, and we don't want to happen unless the
6737 	 * file really is executable.
6738 	 */
6739 	if (!vfs_authopaque(vnode_mount(vp)) && ((vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)) {
6740 		return EACCES;
6741 	}
6742 
6743 	/* Disallow zero length files */
6744 	if (vap->va_data_size == 0) {
6745 		return ENOEXEC;
6746 	}
6747 
6748 	imgp->ip_arch_offset = (user_size_t)0;
6749 #if __LP64__
6750 	imgp->ip_arch_size = vap->va_data_size;
6751 #else
6752 	if (vap->va_data_size > UINT32_MAX) {
6753 		return ENOEXEC;
6754 	}
6755 	imgp->ip_arch_size = (user_size_t)vap->va_data_size;
6756 #endif
6757 
6758 	/* Disable setuid-ness for traced programs or if MNT_NOSUID */
6759 	if ((vp->v_mount->mnt_flag & MNT_NOSUID) || (p->p_lflag & P_LTRACED)) {
6760 		vap->va_mode &= ~(VSUID | VSGID);
6761 	}
6762 
6763 	/*
6764 	 * Disable _POSIX_SPAWN_ALLOW_DATA_EXEC and _POSIX_SPAWN_DISABLE_ASLR
6765 	 * flags for setuid/setgid binaries.
6766 	 */
6767 	if (vap->va_mode & (VSUID | VSGID)) {
6768 		imgp->ip_flags &= ~(IMGPF_ALLOW_DATA_EXEC | IMGPF_DISABLE_ASLR);
6769 	}
6770 
6771 #if CONFIG_MACF
6772 	error = mac_vnode_check_exec(imgp->ip_vfs_context, vp, imgp);
6773 	if (error) {
6774 		return error;
6775 	}
6776 #endif
6777 
6778 	/* Check for execute permission */
6779 	action = KAUTH_VNODE_EXECUTE;
6780 	/* Traced images must also be readable */
6781 	if (p->p_lflag & P_LTRACED) {
6782 		action |= KAUTH_VNODE_READ_DATA;
6783 	}
6784 	if ((error = vnode_authorize(vp, NULL, action, imgp->ip_vfs_context)) != 0) {
6785 		return error;
6786 	}
6787 
6788 #if 0
6789 	/* Don't let it run if anyone had it open for writing */
6790 	vnode_lock(vp);
6791 	if (vp->v_writecount) {
6792 		panic("going to return ETXTBSY %x", vp);
6793 		vnode_unlock(vp);
6794 		return ETXTBSY;
6795 	}
6796 	vnode_unlock(vp);
6797 #endif
6798 
6799 	/* XXX May want to indicate to underlying FS that vnode is open */
6800 
6801 	return error;
6802 }
6803 
6804 
6805 /*
6806  * exec_handle_sugid
6807  *
6808  * Initially clear the P_SUGID in the process flags; if an SUGID process is
6809  * exec'ing a non-SUGID image, then  this is the point of no return.
6810  *
6811  * If the image being activated is SUGID, then replace the credential with a
6812  * copy, disable tracing (unless the tracing process is root), reset the
6813  * mach task port to revoke it, set the P_SUGID bit,
6814  *
6815  * If the saved user and group ID will be changing, then make sure it happens
6816  * to a new credential, rather than a shared one.
6817  *
6818  * Set the security token (this is probably obsolete, given that the token
6819  * should not technically be separate from the credential itself).
6820  *
6821  * Parameters:	struct image_params *	the image parameter block
6822  *
6823  * Returns:	void			No failure indication
6824  *
6825  * Implicit returns:
6826  *		<process credential>	Potentially modified/replaced
6827  *		<task port>		Potentially revoked
6828  *		<process flags>		P_SUGID bit potentially modified
6829  *		<security token>	Potentially modified
6830  */
6831 __attribute__((noinline))
6832 static int
exec_handle_sugid(struct image_params * imgp)6833 exec_handle_sugid(struct image_params *imgp)
6834 {
6835 	proc_t                  p = vfs_context_proc(imgp->ip_vfs_context);
6836 	kauth_cred_t            cred = vfs_context_ucred(imgp->ip_vfs_context);
6837 	int                     i;
6838 	int                     leave_sugid_clear = 0;
6839 	int                     mac_reset_ipc = 0;
6840 	int                     error = 0;
6841 #if CONFIG_MACF
6842 	int                     mac_transition, disjoint_cred = 0;
6843 	int             label_update_return = 0;
6844 
6845 	/*
6846 	 * Determine whether a call to update the MAC label will result in the
6847 	 * credential changing.
6848 	 *
6849 	 * Note:	MAC policies which do not actually end up modifying
6850 	 *		the label subsequently are strongly encouraged to
6851 	 *		return 0 for this check, since a non-zero answer will
6852 	 *		slow down the exec fast path for normal binaries.
6853 	 */
6854 	mac_transition = mac_cred_check_label_update_execve(
6855 		imgp->ip_vfs_context,
6856 		imgp->ip_vp,
6857 		imgp->ip_arch_offset,
6858 		imgp->ip_scriptvp,
6859 		imgp->ip_scriptlabelp,
6860 		imgp->ip_execlabelp,
6861 		p,
6862 		&imgp->ip_px_smpx);
6863 #endif
6864 
6865 	OSBitAndAtomic(~((uint32_t)P_SUGID), &p->p_flag);
6866 
6867 	/*
6868 	 * Order of the following is important; group checks must go last,
6869 	 * as we use the success of the 'ismember' check combined with the
6870 	 * failure of the explicit match to indicate that we will be setting
6871 	 * the egid of the process even though the new process did not
6872 	 * require VSUID/VSGID bits in order for it to set the new group as
6873 	 * its egid.
6874 	 *
6875 	 * Note:	Technically, by this we are implying a call to
6876 	 *		setegid() in the new process, rather than implying
6877 	 *		it used its VSGID bit to set the effective group,
6878 	 *		even though there is no code in that process to make
6879 	 *		such a call.
6880 	 */
6881 	if (((imgp->ip_origvattr->va_mode & VSUID) != 0 &&
6882 	    kauth_cred_getuid(cred) != imgp->ip_origvattr->va_uid) ||
6883 	    ((imgp->ip_origvattr->va_mode & VSGID) != 0 &&
6884 	    ((kauth_cred_ismember_gid(cred, imgp->ip_origvattr->va_gid, &leave_sugid_clear) || !leave_sugid_clear) ||
6885 	    (kauth_cred_getgid(cred) != imgp->ip_origvattr->va_gid)))) {
6886 #if CONFIG_MACF
6887 /* label for MAC transition and neither VSUID nor VSGID */
6888 handle_mac_transition:
6889 #endif
6890 
6891 #if CONFIG_SETUID
6892 		/*
6893 		 * Replace the credential with a copy of itself if euid or
6894 		 * egid change.
6895 		 *
6896 		 * Note:	setuid binaries will automatically opt out of
6897 		 *		group resolver participation as a side effect
6898 		 *		of this operation.  This is an intentional
6899 		 *		part of the security model, which requires a
6900 		 *		participating credential be established by
6901 		 *		escalating privilege, setting up all other
6902 		 *		aspects of the credential including whether
6903 		 *		or not to participate in external group
6904 		 *		membership resolution, then dropping their
6905 		 *		effective privilege to that of the desired
6906 		 *		final credential state.
6907 		 *
6908 		 * Modifications to p_ucred must be guarded using the
6909 		 * proc's ucred lock. This prevents others from accessing
6910 		 * a garbage credential.
6911 		 */
6912 
6913 		if (imgp->ip_origvattr->va_mode & VSUID) {
6914 			kauth_cred_proc_update(p, PROC_SETTOKEN_NONE,
6915 			    ^bool (kauth_cred_t parent __unused, kauth_cred_t model) {
6916 				return kauth_cred_model_setresuid(model,
6917 				KAUTH_UID_NONE,
6918 				imgp->ip_origvattr->va_uid,
6919 				imgp->ip_origvattr->va_uid,
6920 				KAUTH_UID_NONE);
6921 			});
6922 		}
6923 
6924 		if (imgp->ip_origvattr->va_mode & VSGID) {
6925 			kauth_cred_proc_update(p, PROC_SETTOKEN_NONE,
6926 			    ^bool (kauth_cred_t parent __unused, kauth_cred_t model) {
6927 				return kauth_cred_model_setresgid(model,
6928 				KAUTH_GID_NONE,
6929 				imgp->ip_origvattr->va_gid,
6930 				imgp->ip_origvattr->va_gid);
6931 			});
6932 		}
6933 #endif /* CONFIG_SETUID */
6934 
6935 #if CONFIG_MACF
6936 		/*
6937 		 * If a policy has indicated that it will transition the label,
6938 		 * before making the call into the MAC policies, get a new
6939 		 * duplicate credential, so they can modify it without
6940 		 * modifying any others sharing it.
6941 		 */
6942 		if (mac_transition) {
6943 			/*
6944 			 * This hook may generate upcalls that require
6945 			 * importance donation from the kernel.
6946 			 * (23925818)
6947 			 */
6948 			thread_t thread = current_thread();
6949 			thread_enable_send_importance(thread, TRUE);
6950 			kauth_proc_label_update_execve(p,
6951 			    imgp->ip_vfs_context,
6952 			    imgp->ip_vp,
6953 			    imgp->ip_arch_offset,
6954 			    imgp->ip_scriptvp,
6955 			    imgp->ip_scriptlabelp,
6956 			    imgp->ip_execlabelp,
6957 			    &imgp->ip_csflags,
6958 			    &imgp->ip_px_smpx,
6959 			    &disjoint_cred,                     /* will be non zero if disjoint */
6960 			    &label_update_return);
6961 			thread_enable_send_importance(thread, FALSE);
6962 
6963 			if (disjoint_cred) {
6964 				/*
6965 				 * If updating the MAC label resulted in a
6966 				 * disjoint credential, flag that we need to
6967 				 * set the P_SUGID bit.  This protects
6968 				 * against debuggers being attached by an
6969 				 * insufficiently privileged process onto the
6970 				 * result of a transition to a more privileged
6971 				 * credential.
6972 				 */
6973 				leave_sugid_clear = 0;
6974 			}
6975 
6976 			imgp->ip_mac_return = label_update_return;
6977 		}
6978 
6979 		mac_reset_ipc = mac_proc_check_inherit_ipc_ports(p, p->p_textvp, p->p_textoff, imgp->ip_vp, imgp->ip_arch_offset, imgp->ip_scriptvp);
6980 
6981 #endif  /* CONFIG_MACF */
6982 
6983 		/*
6984 		 * If 'leave_sugid_clear' is non-zero, then we passed the
6985 		 * VSUID and MACF checks, and successfully determined that
6986 		 * the previous cred was a member of the VSGID group, but
6987 		 * that it was not the default at the time of the execve,
6988 		 * and that the post-labelling credential was not disjoint.
6989 		 * So we don't set the P_SUGID or reset mach ports and fds
6990 		 * on the basis of simply running this code.
6991 		 */
6992 		if (mac_reset_ipc || !leave_sugid_clear) {
6993 			/*
6994 			 * Have mach reset the task and thread ports.
6995 			 * We don't want anyone who had the ports before
6996 			 * a setuid exec to be able to access/control the
6997 			 * task/thread after.
6998 			 */
6999 			ipc_task_reset((imgp->ip_new_thread != NULL) ?
7000 			    get_threadtask(imgp->ip_new_thread) : proc_task(p));
7001 			ipc_thread_reset((imgp->ip_new_thread != NULL) ?
7002 			    imgp->ip_new_thread : current_thread());
7003 		}
7004 
7005 		if (!leave_sugid_clear) {
7006 			/*
7007 			 * Flag the process as setuid.
7008 			 */
7009 			OSBitOrAtomic(P_SUGID, &p->p_flag);
7010 
7011 			/*
7012 			 * Radar 2261856; setuid security hole fix
7013 			 * XXX For setuid processes, attempt to ensure that
7014 			 * stdin, stdout, and stderr are already allocated.
7015 			 * We do not want userland to accidentally allocate
7016 			 * descriptors in this range which has implied meaning
7017 			 * to libc.
7018 			 */
7019 			for (i = 0; i < 3; i++) {
7020 				if (fp_get_noref_locked(p, i) != NULL) {
7021 					continue;
7022 				}
7023 
7024 				/*
7025 				 * Do the kernel equivalent of
7026 				 *
7027 				 *      if i == 0
7028 				 *              (void) open("/dev/null", O_RDONLY);
7029 				 *      else
7030 				 *              (void) open("/dev/null", O_WRONLY);
7031 				 */
7032 
7033 				struct fileproc *fp;
7034 				int indx;
7035 				int flag;
7036 				struct nameidata *ndp = NULL;
7037 
7038 				if (i == 0) {
7039 					flag = FREAD;
7040 				} else {
7041 					flag = FWRITE;
7042 				}
7043 
7044 				if ((error = falloc_exec(p, imgp->ip_vfs_context,
7045 				    &fp, &indx)) != 0) {
7046 					continue;
7047 				}
7048 
7049 				ndp = kalloc_type(struct nameidata,
7050 				    Z_WAITOK | Z_ZERO | Z_NOFAIL);
7051 
7052 				NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW, UIO_SYSSPACE,
7053 				    CAST_USER_ADDR_T("/dev/null"),
7054 				    imgp->ip_vfs_context);
7055 
7056 				if ((error = vn_open(ndp, flag, 0)) != 0) {
7057 					fp_free(p, indx, fp);
7058 					kfree_type(struct nameidata, ndp);
7059 					break;
7060 				}
7061 
7062 				struct fileglob *fg = fp->fp_glob;
7063 
7064 				fg->fg_flag = flag;
7065 				fg->fg_ops = &vnops;
7066 				fp_set_data(fp, ndp->ni_vp);
7067 
7068 				vnode_put(ndp->ni_vp);
7069 
7070 				proc_fdlock(p);
7071 				procfdtbl_releasefd(p, indx, NULL);
7072 				fp_drop(p, indx, fp, 1);
7073 				proc_fdunlock(p);
7074 
7075 				kfree_type(struct nameidata, ndp);
7076 			}
7077 		}
7078 	}
7079 #if CONFIG_MACF
7080 	else {
7081 		/*
7082 		 * We are here because we were told that the MAC label will
7083 		 * be transitioned, and the binary is not VSUID or VSGID; to
7084 		 * deal with this case, we could either duplicate a lot of
7085 		 * code, or we can indicate we want to default the P_SUGID
7086 		 * bit clear and jump back up.
7087 		 */
7088 		if (mac_transition) {
7089 			leave_sugid_clear = 1;
7090 			goto handle_mac_transition;
7091 		}
7092 	}
7093 
7094 #endif  /* CONFIG_MACF */
7095 
7096 	/* Update the process' identity version and set the security token.
7097 	 * Also, ensure we always see a modified identity version (rdar://129775819).
7098 	 */
7099 	int previous_pid_version = proc_get_ro(p)->p_idversion;
7100 	int new_pid_version;
7101 	do {
7102 		new_pid_version = OSIncrementAtomic(&nextpidversion);
7103 	} while (new_pid_version == previous_pid_version);
7104 	proc_setpidversion(p, new_pid_version);
7105 	task_set_uniqueid(proc_task(p));
7106 
7107 	/*
7108 	 * Implement the semantic where the effective user and group become
7109 	 * the saved user and group in exec'ed programs.
7110 	 */
7111 	kauth_cred_proc_update(p, PROC_SETTOKEN_ALWAYS,
7112 	    ^bool (kauth_cred_t parent __unused, kauth_cred_t model) {
7113 		posix_cred_t pcred = posix_cred_get(model);
7114 
7115 		if (pcred->cr_svuid == pcred->cr_uid &&
7116 		pcred->cr_svgid == pcred->cr_gid) {
7117 		        return false;
7118 		}
7119 
7120 		pcred->cr_svuid = pcred->cr_uid;
7121 		pcred->cr_svgid = pcred->cr_gid;
7122 		return true;
7123 	});
7124 
7125 	return error;
7126 }
7127 
7128 
7129 /*
7130  * create_unix_stack
7131  *
7132  * Description:	Set the user stack address for the process to the provided
7133  *		address.  If a custom stack was not set as a result of the
7134  *		load process (i.e. as specified by the image file for the
7135  *		executable), then allocate the stack in the provided map and
7136  *		set up appropriate guard pages for enforcing administrative
7137  *		limits on stack growth, if they end up being needed.
7138  *
7139  * Parameters:	p			Process to set stack on
7140  *		load_result		Information from mach-o load commands
7141  *		map			Address map in which to allocate the new stack
7142  *
7143  * Returns:	KERN_SUCCESS		Stack successfully created
7144  *		!KERN_SUCCESS		Mach failure code
7145  */
7146 __attribute__((noinline))
7147 static kern_return_t
create_unix_stack(vm_map_t map,load_result_t * load_result,proc_t p)7148 create_unix_stack(vm_map_t map, load_result_t* load_result,
7149     proc_t p)
7150 {
7151 	mach_vm_size_t          size, prot_size;
7152 	mach_vm_offset_t        addr, prot_addr;
7153 	kern_return_t           kr;
7154 
7155 	mach_vm_address_t       user_stack = load_result->user_stack;
7156 
7157 	proc_lock(p);
7158 	p->user_stack = (uintptr_t)user_stack;
7159 	if (load_result->custom_stack) {
7160 		p->p_lflag |= P_LCUSTOM_STACK;
7161 	}
7162 	proc_unlock(p);
7163 	if (vm_map_page_shift(map) < (int)PAGE_SHIFT) {
7164 		DEBUG4K_LOAD("map %p user_stack 0x%llx custom %d user_stack_alloc_size 0x%llx\n", map, user_stack, load_result->custom_stack, load_result->user_stack_alloc_size);
7165 	}
7166 
7167 	if (load_result->user_stack_alloc_size > 0) {
7168 		/*
7169 		 * Allocate enough space for the maximum stack size we
7170 		 * will ever authorize and an extra page to act as
7171 		 * a guard page for stack overflows. For default stacks,
7172 		 * vm_initial_limit_stack takes care of the extra guard page.
7173 		 * Otherwise we must allocate it ourselves.
7174 		 */
7175 		if (mach_vm_round_page_overflow(load_result->user_stack_alloc_size, &size)) {
7176 			return KERN_INVALID_ARGUMENT;
7177 		}
7178 		addr = vm_map_trunc_page(load_result->user_stack - size,
7179 		    vm_map_page_mask(map));
7180 		kr = mach_vm_allocate_kernel(map, &addr, size,
7181 		    VM_MAP_KERNEL_FLAGS_FIXED(.vm_tag = VM_MEMORY_STACK));
7182 		if (kr != KERN_SUCCESS) {
7183 			// Can't allocate at default location, try anywhere
7184 			addr = 0;
7185 			kr = mach_vm_allocate_kernel(map, &addr, size,
7186 			    VM_MAP_KERNEL_FLAGS_ANYWHERE(.vm_tag = VM_MEMORY_STACK));
7187 			if (kr != KERN_SUCCESS) {
7188 				return kr;
7189 			}
7190 
7191 			user_stack = addr + size;
7192 			load_result->user_stack = (user_addr_t)user_stack;
7193 
7194 			proc_lock(p);
7195 			p->user_stack = (uintptr_t)user_stack;
7196 			proc_unlock(p);
7197 		}
7198 
7199 		load_result->user_stack_alloc = (user_addr_t)addr;
7200 
7201 		/*
7202 		 * And prevent access to what's above the current stack
7203 		 * size limit for this process.
7204 		 */
7205 		if (load_result->user_stack_size == 0) {
7206 			load_result->user_stack_size = proc_limitgetcur(p, RLIMIT_STACK);
7207 			prot_size = vm_map_trunc_page(size - load_result->user_stack_size, vm_map_page_mask(map));
7208 		} else {
7209 			prot_size = PAGE_SIZE;
7210 		}
7211 
7212 		prot_addr = addr;
7213 		kr = mach_vm_protect(map,
7214 		    prot_addr,
7215 		    prot_size,
7216 		    FALSE,
7217 		    VM_PROT_NONE);
7218 		if (kr != KERN_SUCCESS) {
7219 			(void)mach_vm_deallocate(map, addr, size);
7220 			return kr;
7221 		}
7222 	}
7223 
7224 	return KERN_SUCCESS;
7225 }
7226 
7227 #include <sys/reboot.h>
7228 
7229 /*
7230  * load_init_program_at_path
7231  *
7232  * Description:	Load the "init" program; in most cases, this will be "launchd"
7233  *
7234  * Parameters:	p			Process to call execve() to create
7235  *					the "init" program
7236  *		scratch_addr		Page in p, scratch space
7237  *		path			NULL terminated path
7238  *
7239  * Returns:	KERN_SUCCESS		Success
7240  *		!KERN_SUCCESS           See execve/mac_execve for error codes
7241  *
7242  * Notes:	The process that is passed in is the first manufactured
7243  *		process on the system, and gets here via bsd_ast() firing
7244  *		for the first time.  This is done to ensure that bsd_init()
7245  *		has run to completion.
7246  *
7247  *		The address map of the first manufactured process matches the
7248  *		word width of the kernel. Once the self-exec completes, the
7249  *		initproc might be different.
7250  */
7251 static int
load_init_program_at_path(proc_t p,user_addr_t scratch_addr,const char * path)7252 load_init_program_at_path(proc_t p, user_addr_t scratch_addr, const char* path)
7253 {
7254 	int retval[2];
7255 	int error;
7256 	struct execve_args init_exec_args;
7257 	user_addr_t argv0 = USER_ADDR_NULL, argv1 = USER_ADDR_NULL;
7258 
7259 	/*
7260 	 * Validate inputs and pre-conditions
7261 	 */
7262 	assert(p);
7263 	assert(scratch_addr);
7264 	assert(path);
7265 
7266 	/*
7267 	 * Copy out program name.
7268 	 */
7269 	size_t path_length = strlen(path) + 1;
7270 	argv0 = scratch_addr;
7271 	error = copyout(path, argv0, path_length);
7272 	if (error) {
7273 		return error;
7274 	}
7275 
7276 	scratch_addr = USER_ADDR_ALIGN(scratch_addr + path_length, sizeof(user_addr_t));
7277 
7278 	/*
7279 	 * Put out first (and only) argument, similarly.
7280 	 * Assumes everything fits in a page as allocated above.
7281 	 */
7282 	if (boothowto & RB_SINGLE) {
7283 		const char *init_args = "-s";
7284 		size_t init_args_length = strlen(init_args) + 1;
7285 
7286 		argv1 = scratch_addr;
7287 		error = copyout(init_args, argv1, init_args_length);
7288 		if (error) {
7289 			return error;
7290 		}
7291 
7292 		scratch_addr = USER_ADDR_ALIGN(scratch_addr + init_args_length, sizeof(user_addr_t));
7293 	}
7294 
7295 	if (proc_is64bit(p)) {
7296 		user64_addr_t argv64bit[3] = {};
7297 
7298 		argv64bit[0] = argv0;
7299 		argv64bit[1] = argv1;
7300 		argv64bit[2] = USER_ADDR_NULL;
7301 
7302 		error = copyout(argv64bit, scratch_addr, sizeof(argv64bit));
7303 		if (error) {
7304 			return error;
7305 		}
7306 	} else {
7307 		user32_addr_t argv32bit[3] = {};
7308 
7309 		argv32bit[0] = (user32_addr_t)argv0;
7310 		argv32bit[1] = (user32_addr_t)argv1;
7311 		argv32bit[2] = USER_ADDR_NULL;
7312 
7313 		error = copyout(argv32bit, scratch_addr, sizeof(argv32bit));
7314 		if (error) {
7315 			return error;
7316 		}
7317 	}
7318 
7319 	/*
7320 	 * Set up argument block for fake call to execve.
7321 	 */
7322 	init_exec_args.fname = argv0;
7323 	init_exec_args.argp = scratch_addr;
7324 	init_exec_args.envp = USER_ADDR_NULL;
7325 
7326 	/*
7327 	 * So that init task is set with uid,gid 0 token
7328 	 *
7329 	 * The access to the cred is safe:
7330 	 * the proc isn't running yet, it's stable.
7331 	 */
7332 	set_security_token(p, proc_ucred_unsafe(p));
7333 
7334 	return execve(p, &init_exec_args, retval);
7335 }
7336 
7337 static const char * init_programs[] = {
7338 #if DEBUG
7339 	"/usr/appleinternal/sbin/launchd.debug",
7340 #endif
7341 #if DEVELOPMENT || DEBUG
7342 	"/usr/appleinternal/sbin/launchd.development",
7343 #endif
7344 	"/sbin/launchd",
7345 };
7346 
7347 /*
7348  * load_init_program
7349  *
7350  * Description:	Load the "init" program; in most cases, this will be "launchd"
7351  *
7352  * Parameters:	p			Process to call execve() to create
7353  *					the "init" program
7354  *
7355  * Returns:	(void)
7356  *
7357  * Notes:	The process that is passed in is the first manufactured
7358  *		process on the system, and gets here via bsd_ast() firing
7359  *		for the first time.  This is done to ensure that bsd_init()
7360  *		has run to completion.
7361  *
7362  *		In DEBUG & DEVELOPMENT builds, the launchdsuffix boot-arg
7363  *		may be used to select a specific launchd executable. As with
7364  *		the kcsuffix boot-arg, setting launchdsuffix to "" or "release"
7365  *		will force /sbin/launchd to be selected.
7366  *
7367  *              Search order by build:
7368  *
7369  * DEBUG	DEVELOPMENT	RELEASE		PATH
7370  * ----------------------------------------------------------------------------------
7371  * 1		1		NA		/usr/appleinternal/sbin/launchd.$LAUNCHDSUFFIX
7372  * 2		NA		NA		/usr/appleinternal/sbin/launchd.debug
7373  * 3		2		NA		/usr/appleinternal/sbin/launchd.development
7374  * 4		3		1		/sbin/launchd
7375  */
7376 void
load_init_program(proc_t p)7377 load_init_program(proc_t p)
7378 {
7379 	uint32_t i;
7380 	int error;
7381 	vm_map_t map = current_map();
7382 	mach_vm_offset_t scratch_addr = 0;
7383 	mach_vm_size_t map_page_size = vm_map_page_size(map);
7384 
7385 #if DEVELOPMENT || DEBUG
7386 	/* Use the opportunity to initialize exec's debug log stream */
7387 	exec_log_handle = os_log_create("com.apple.xnu.bsd", "exec");
7388 #endif /* DEVELOPMENT || DEBUG */
7389 
7390 	(void) mach_vm_allocate_kernel(map, &scratch_addr, map_page_size,
7391 	    VM_MAP_KERNEL_FLAGS_ANYWHERE());
7392 #if CONFIG_MEMORYSTATUS
7393 	(void) memorystatus_init_at_boot_snapshot();
7394 #endif /* CONFIG_MEMORYSTATUS */
7395 
7396 #if DEBUG || DEVELOPMENT
7397 	/* Check for boot-arg suffix first */
7398 	char launchd_suffix[64];
7399 	if (PE_parse_boot_argn("launchdsuffix", launchd_suffix, sizeof(launchd_suffix))) {
7400 		char launchd_path[128];
7401 		boolean_t is_release_suffix = ((launchd_suffix[0] == 0) ||
7402 		    (strcmp(launchd_suffix, "release") == 0));
7403 
7404 		if (is_release_suffix) {
7405 			printf("load_init_program: attempting to load /sbin/launchd\n");
7406 			error = load_init_program_at_path(p, (user_addr_t)scratch_addr, "/sbin/launchd");
7407 			if (!error) {
7408 				return;
7409 			}
7410 
7411 			panic("Process 1 exec of launchd.release failed, errno %d", error);
7412 		} else {
7413 			strlcpy(launchd_path, "/usr/appleinternal/sbin/launchd.", sizeof(launchd_path));
7414 			strlcat(launchd_path, launchd_suffix, sizeof(launchd_path));
7415 
7416 			printf("load_init_program: attempting to load %s\n", launchd_path);
7417 			error = load_init_program_at_path(p, (user_addr_t)scratch_addr, launchd_path);
7418 			if (!error) {
7419 				return;
7420 			} else if (error != ENOENT) {
7421 				printf("load_init_program: failed loading %s: errno %d\n", launchd_path, error);
7422 			}
7423 		}
7424 	}
7425 #endif
7426 
7427 	error = ENOENT;
7428 	for (i = 0; i < sizeof(init_programs) / sizeof(init_programs[0]); i++) {
7429 		printf("load_init_program: attempting to load %s\n", init_programs[i]);
7430 		error = load_init_program_at_path(p, (user_addr_t)scratch_addr, init_programs[i]);
7431 		if (!error) {
7432 			return;
7433 		} else if (error != ENOENT) {
7434 			printf("load_init_program: failed loading %s: errno %d\n", init_programs[i], error);
7435 		}
7436 	}
7437 
7438 	panic("Process 1 exec of %s failed, errno %d", ((i == 0) ? "<null>" : init_programs[i - 1]), error);
7439 }
7440 
7441 /*
7442  * load_return_to_errno
7443  *
7444  * Description:	Convert a load_return_t (Mach error) to an errno (BSD error)
7445  *
7446  * Parameters:	lrtn			Mach error number
7447  *
7448  * Returns:	(int)			BSD error number
7449  *		0			Success
7450  *		EBADARCH		Bad architecture
7451  *		EBADMACHO		Bad Mach object file
7452  *		ESHLIBVERS		Bad shared library version
7453  *		ENOMEM			Out of memory/resource shortage
7454  *		EACCES			Access denied
7455  *		ENOENT			Entry not found (usually "file does
7456  *					does not exist")
7457  *		EIO			An I/O error occurred
7458  *		EBADEXEC		The executable is corrupt/unknown
7459  */
7460 static int
load_return_to_errno(load_return_t lrtn)7461 load_return_to_errno(load_return_t lrtn)
7462 {
7463 	switch (lrtn) {
7464 	case LOAD_SUCCESS:
7465 		return 0;
7466 	case LOAD_BADARCH:
7467 		return EBADARCH;
7468 	case LOAD_BADMACHO:
7469 	case LOAD_BADMACHO_UPX:
7470 		return EBADMACHO;
7471 	case LOAD_SHLIB:
7472 		return ESHLIBVERS;
7473 	case LOAD_NOSPACE:
7474 	case LOAD_RESOURCE:
7475 		return ENOMEM;
7476 	case LOAD_PROTECT:
7477 		return EACCES;
7478 	case LOAD_ENOENT:
7479 		return ENOENT;
7480 	case LOAD_IOERROR:
7481 		return EIO;
7482 	case LOAD_DECRYPTFAIL:
7483 		return EAUTH;
7484 	case LOAD_FAILURE:
7485 	default:
7486 		return EBADEXEC;
7487 	}
7488 }
7489 
7490 #include <mach/mach_types.h>
7491 #include <mach/vm_prot.h>
7492 #include <mach/semaphore.h>
7493 #include <mach/sync_policy.h>
7494 #include <kern/clock.h>
7495 #include <mach/kern_return.h>
7496 
7497 /*
7498  * execargs_alloc
7499  *
7500  * Description:	Allocate the block of memory used by the execve arguments.
7501  *		At the same time, we allocate a page so that we can read in
7502  *		the first page of the image.
7503  *
7504  * Parameters:	struct image_params *	the image parameter block
7505  *
7506  * Returns:	0			Success
7507  *		EINVAL			Invalid argument
7508  *		EACCES			Permission denied
7509  *		EINTR			Interrupted function
7510  *		ENOMEM			Not enough space
7511  *
7512  * Notes:	This is a temporary allocation into the kernel address space
7513  *		to enable us to copy arguments in from user space.  This is
7514  *		necessitated by not mapping the process calling execve() into
7515  *		the kernel address space during the execve() system call.
7516  *
7517  *		We assemble the argument and environment, etc., into this
7518  *		region before copying it as a single block into the child
7519  *		process address space (at the top or bottom of the stack,
7520  *		depending on which way the stack grows; see the function
7521  *		exec_copyout_strings() for details).
7522  *
7523  *		This ends up with a second (possibly unnecessary) copy compared
7524  *		with assembing the data directly into the child address space,
7525  *		instead, but since we cannot be guaranteed that the parent has
7526  *		not modified its environment, we can't really know that it's
7527  *		really a block there as well.
7528  */
7529 
7530 
7531 static int execargs_waiters = 0;
7532 static LCK_MTX_DECLARE_ATTR(execargs_cache_lock, &proc_lck_grp, &proc_lck_attr);
7533 
7534 static void
execargs_lock_lock(void)7535 execargs_lock_lock(void)
7536 {
7537 	lck_mtx_lock_spin(&execargs_cache_lock);
7538 }
7539 
7540 static void
execargs_lock_unlock(void)7541 execargs_lock_unlock(void)
7542 {
7543 	lck_mtx_unlock(&execargs_cache_lock);
7544 }
7545 
7546 static wait_result_t
execargs_lock_sleep(void)7547 execargs_lock_sleep(void)
7548 {
7549 	return lck_mtx_sleep(&execargs_cache_lock, LCK_SLEEP_DEFAULT, &execargs_free_count, THREAD_INTERRUPTIBLE);
7550 }
7551 
7552 static kern_return_t
execargs_purgeable_allocate(char ** execarg_address)7553 execargs_purgeable_allocate(char **execarg_address)
7554 {
7555 	mach_vm_offset_t addr = 0;
7556 	kern_return_t kr = mach_vm_allocate_kernel(bsd_pageable_map, &addr,
7557 	    BSD_PAGEABLE_SIZE_PER_EXEC,
7558 	    VM_MAP_KERNEL_FLAGS_ANYWHERE(.vmf_purgeable = true));
7559 	*execarg_address = (char *)addr;
7560 	assert(kr == KERN_SUCCESS);
7561 	return kr;
7562 }
7563 
7564 static kern_return_t
execargs_purgeable_reference(void * execarg_address)7565 execargs_purgeable_reference(void *execarg_address)
7566 {
7567 	int state = VM_PURGABLE_NONVOLATILE;
7568 	kern_return_t kr = vm_map_purgable_control(bsd_pageable_map,
7569 	    (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
7570 
7571 	assert(kr == KERN_SUCCESS);
7572 	return kr;
7573 }
7574 
7575 static kern_return_t
execargs_purgeable_volatilize(void * execarg_address)7576 execargs_purgeable_volatilize(void *execarg_address)
7577 {
7578 	int state = VM_PURGABLE_VOLATILE | VM_PURGABLE_ORDERING_OBSOLETE;
7579 	kern_return_t kr;
7580 	kr = vm_map_purgable_control(bsd_pageable_map,
7581 	    (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
7582 
7583 	assert(kr == KERN_SUCCESS);
7584 
7585 	return kr;
7586 }
7587 
7588 static void
execargs_wakeup_waiters(void)7589 execargs_wakeup_waiters(void)
7590 {
7591 	thread_wakeup(&execargs_free_count);
7592 }
7593 
7594 static int
execargs_alloc(struct image_params * imgp)7595 execargs_alloc(struct image_params *imgp)
7596 {
7597 	kern_return_t kret;
7598 	wait_result_t res;
7599 	int i, cache_index = -1;
7600 
7601 	execargs_lock_lock();
7602 
7603 	while (execargs_free_count == 0) {
7604 		execargs_waiters++;
7605 		res = execargs_lock_sleep();
7606 		execargs_waiters--;
7607 		if (res != THREAD_AWAKENED) {
7608 			execargs_lock_unlock();
7609 			return EINTR;
7610 		}
7611 	}
7612 
7613 	execargs_free_count--;
7614 
7615 	for (i = 0; i < execargs_cache_size; i++) {
7616 		vm_offset_t element = execargs_cache[i];
7617 		if (element) {
7618 			cache_index = i;
7619 			imgp->ip_strings = (char *)(execargs_cache[i]);
7620 			execargs_cache[i] = 0;
7621 			break;
7622 		}
7623 	}
7624 
7625 	assert(execargs_free_count >= 0);
7626 
7627 	execargs_lock_unlock();
7628 
7629 	if (cache_index == -1) {
7630 		kret = execargs_purgeable_allocate(&imgp->ip_strings);
7631 	} else {
7632 		kret = execargs_purgeable_reference(imgp->ip_strings);
7633 	}
7634 
7635 	assert(kret == KERN_SUCCESS);
7636 	if (kret != KERN_SUCCESS) {
7637 		return ENOMEM;
7638 	}
7639 
7640 	/* last page used to read in file headers */
7641 	imgp->ip_vdata = imgp->ip_strings + (NCARGS + PAGE_SIZE);
7642 	imgp->ip_strendp = imgp->ip_strings;
7643 	imgp->ip_argspace = NCARGS;
7644 	imgp->ip_strspace = (NCARGS + PAGE_SIZE);
7645 
7646 	return 0;
7647 }
7648 
7649 /*
7650  * execargs_free
7651  *
7652  * Description:	Free the block of memory used by the execve arguments and the
7653  *		first page of the executable by a previous call to the function
7654  *		execargs_alloc().
7655  *
7656  * Parameters:	struct image_params *	the image parameter block
7657  *
7658  * Returns:	0			Success
7659  *		EINVAL			Invalid argument
7660  *		EINTR			Oeration interrupted
7661  */
7662 static int
execargs_free(struct image_params * imgp)7663 execargs_free(struct image_params *imgp)
7664 {
7665 	kern_return_t kret;
7666 	int i;
7667 	boolean_t needs_wakeup = FALSE;
7668 
7669 	kret = execargs_purgeable_volatilize(imgp->ip_strings);
7670 
7671 	execargs_lock_lock();
7672 	execargs_free_count++;
7673 
7674 	for (i = 0; i < execargs_cache_size; i++) {
7675 		vm_offset_t element = execargs_cache[i];
7676 		if (element == 0) {
7677 			execargs_cache[i] = (vm_offset_t) imgp->ip_strings;
7678 			imgp->ip_strings = NULL;
7679 			break;
7680 		}
7681 	}
7682 
7683 	assert(imgp->ip_strings == NULL);
7684 
7685 	if (execargs_waiters > 0) {
7686 		needs_wakeup = TRUE;
7687 	}
7688 
7689 	execargs_lock_unlock();
7690 
7691 	if (needs_wakeup == TRUE) {
7692 		execargs_wakeup_waiters();
7693 	}
7694 
7695 	return kret == KERN_SUCCESS ? 0 : EINVAL;
7696 }
7697 
7698 void
uthread_set_exec_data(struct uthread * uth,struct image_params * imgp)7699 uthread_set_exec_data(struct uthread *uth, struct image_params *imgp)
7700 {
7701 	uth->uu_save.uus_exec_data.imgp = imgp;
7702 }
7703 
7704 size_t
thread_get_current_exec_path(char * path,size_t size)7705 thread_get_current_exec_path(char *path, size_t size)
7706 {
7707 	struct uthread *uth = current_uthread();
7708 	struct image_params *imgp = uth->uu_save.uus_exec_data.imgp;
7709 	size_t string_size = 0;
7710 	char *exec_path;
7711 
7712 	if (path == NULL || imgp == NULL || imgp->ip_strings == NULL) {
7713 		return 0;
7714 	}
7715 
7716 	exec_path = imgp->ip_strings + strlen(EXECUTABLE_KEY);
7717 	string_size = imgp->ip_strendp - exec_path;
7718 	string_size = MIN(MAXPATHLEN, string_size);
7719 	string_size = MIN(size, string_size);
7720 
7721 	string_size = strlcpy(path, exec_path, string_size);
7722 	return string_size;
7723 }
7724 static void
exec_resettextvp(proc_t p,struct image_params * imgp)7725 exec_resettextvp(proc_t p, struct image_params *imgp)
7726 {
7727 	vnode_t vp;
7728 	off_t offset;
7729 	vnode_t tvp  = p->p_textvp;
7730 	int ret;
7731 
7732 	vp = imgp->ip_vp;
7733 	offset = imgp->ip_arch_offset;
7734 
7735 	if (vp == NULLVP) {
7736 		panic("exec_resettextvp: expected valid vp");
7737 	}
7738 
7739 	ret = vnode_ref(vp);
7740 	proc_lock(p);
7741 	if (ret == 0) {
7742 		p->p_textvp = vp;
7743 		p->p_textoff = offset;
7744 	} else {
7745 		p->p_textvp = NULLVP;   /* this is paranoia */
7746 		p->p_textoff = 0;
7747 	}
7748 	proc_unlock(p);
7749 
7750 	if (tvp != NULLVP) {
7751 		if (vnode_getwithref(tvp) == 0) {
7752 			vnode_rele(tvp);
7753 			vnode_put(tvp);
7754 		}
7755 	}
7756 }
7757 
7758 // Includes the 0-byte (therefore "SIZE" instead of "LEN").
7759 static const size_t CS_CDHASH_STRING_SIZE = CS_CDHASH_LEN * 2 + 1;
7760 
7761 static void
cdhash_to_string(char str[CS_CDHASH_STRING_SIZE],uint8_t const * const cdhash)7762 cdhash_to_string(char str[CS_CDHASH_STRING_SIZE], uint8_t const * const cdhash)
7763 {
7764 	static char const nibble[] = "0123456789abcdef";
7765 
7766 	/* Apparently still the safest way to get a hex representation
7767 	 * of binary data.
7768 	 * xnu's printf routines have %*D/%20D in theory, but "not really", see:
7769 	 * <rdar://problem/33328859> confusion around %*D/%nD in printf
7770 	 */
7771 	for (int i = 0; i < CS_CDHASH_LEN; ++i) {
7772 		str[i * 2] = nibble[(cdhash[i] & 0xf0) >> 4];
7773 		str[i * 2 + 1] = nibble[cdhash[i] & 0x0f];
7774 	}
7775 	str[CS_CDHASH_STRING_SIZE - 1] = 0;
7776 }
7777 
7778 /*
7779  * __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__
7780  *
7781  * Description: Waits for the userspace daemon to respond to the request
7782  *              we made. Function declared non inline to be visible in
7783  *		stackshots and spindumps as well as debugging.
7784  */
7785 __attribute__((noinline)) int
__EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port,int32_t new_pid)7786 __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid)
7787 {
7788 	return find_code_signature(task_access_port, new_pid);
7789 }
7790 
7791 /*
7792  * Update signature dependent process state, called by
7793  * process_signature.
7794  */
7795 static int
proc_process_signature(proc_t p,os_reason_t * signature_failure_reason)7796 proc_process_signature(proc_t p, os_reason_t *signature_failure_reason)
7797 {
7798 	int error = 0;
7799 	char const *error_msg = NULL;
7800 
7801 	kern_return_t kr = machine_task_process_signature(proc_get_task_raw(p), proc_platform(p), proc_sdk(p), &error_msg);
7802 
7803 	if (kr != KERN_SUCCESS) {
7804 		error = EINVAL;
7805 
7806 		if (error_msg != NULL) {
7807 			uint32_t error_msg_len = (uint32_t)strlen(error_msg) + 1;
7808 			mach_vm_address_t data_addr = 0;
7809 			int reason_error = 0;
7810 			int kcdata_error = 0;
7811 
7812 			os_reason_t reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
7813 			reason->osr_flags = OS_REASON_FLAG_GENERATE_CRASH_REPORT | OS_REASON_FLAG_CONSISTENT_FAILURE;
7814 
7815 			if ((reason_error = os_reason_alloc_buffer_noblock(reason,
7816 			    kcdata_estimate_required_buffer_size(1, error_msg_len))) == 0 &&
7817 			    (kcdata_error = kcdata_get_memory_addr(&reason->osr_kcd_descriptor,
7818 			    EXIT_REASON_USER_DESC, error_msg_len,
7819 			    &data_addr)) == KERN_SUCCESS) {
7820 				kern_return_t mc_error = kcdata_memcpy(&reason->osr_kcd_descriptor, (mach_vm_address_t)data_addr,
7821 				    error_msg, error_msg_len);
7822 
7823 				if (mc_error != KERN_SUCCESS) {
7824 					printf("process_signature: failed to copy reason string (kcdata_memcpy error: %d)\n",
7825 					    mc_error);
7826 				}
7827 			} else {
7828 				printf("failed to allocate space for reason string (os_reason_alloc_buffer error: %d, kcdata error: %d, length: %u)\n",
7829 				    reason_error, kcdata_error, error_msg_len);
7830 			}
7831 
7832 			assert(*signature_failure_reason == NULL); // shouldn't have gotten so far
7833 			*signature_failure_reason = reason;
7834 		}
7835 	}
7836 	return error;
7837 }
7838 
7839 
7840 #define DT_UNRESTRICTED_SUBSYSTEM_ROOT "unrestricted-subsystem-root"
7841 
7842 static bool
allow_unrestricted_subsystem_root(void)7843 allow_unrestricted_subsystem_root(void)
7844 {
7845 #if !(DEVELOPMENT || DEBUG)
7846 	static bool allow_unrestricted_subsystem_root = false;
7847 	static bool has_been_set = false;
7848 
7849 	if (!has_been_set) {
7850 		DTEntry chosen;
7851 		const uint32_t *value;
7852 		unsigned size;
7853 
7854 		has_been_set = true;
7855 		if (SecureDTLookupEntry(0, "/chosen", &chosen) == kSuccess &&
7856 		    SecureDTGetProperty(chosen, DT_UNRESTRICTED_SUBSYSTEM_ROOT, (const void**)&value, &size) == kSuccess &&
7857 		    value != NULL &&
7858 		    size == sizeof(uint32_t)) {
7859 			allow_unrestricted_subsystem_root = (bool)*value;
7860 		}
7861 	}
7862 
7863 	return allow_unrestricted_subsystem_root;
7864 #else
7865 	return true;
7866 #endif
7867 }
7868 
7869 static int
process_signature(proc_t p,struct image_params * imgp)7870 process_signature(proc_t p, struct image_params *imgp)
7871 {
7872 	mach_port_t port = IPC_PORT_NULL;
7873 	kern_return_t kr = KERN_FAILURE;
7874 	int error = EACCES;
7875 	boolean_t unexpected_failure = FALSE;
7876 	struct cs_blob *csb;
7877 	boolean_t require_success = FALSE;
7878 	int spawn = (imgp->ip_flags & IMGPF_SPAWN);
7879 	const int vfexec = 0;
7880 	os_reason_t signature_failure_reason = OS_REASON_NULL;
7881 
7882 	/*
7883 	 * Override inherited code signing flags with the
7884 	 * ones for the process that is being successfully
7885 	 * loaded
7886 	 */
7887 	proc_lock(p);
7888 	proc_csflags_update(p, imgp->ip_csflags);
7889 	proc_unlock(p);
7890 
7891 	/* Set the switch_protect flag on the map */
7892 	if (proc_getcsflags(p) & (CS_HARD | CS_KILL)) {
7893 		vm_map_switch_protect(get_task_map(proc_task(p)), TRUE);
7894 	}
7895 	/* set the cs_enforced flags in the map */
7896 	if (proc_getcsflags(p) & CS_ENFORCEMENT) {
7897 		vm_map_cs_enforcement_set(get_task_map(proc_task(p)), TRUE);
7898 	} else {
7899 		vm_map_cs_enforcement_set(get_task_map(proc_task(p)), FALSE);
7900 	}
7901 
7902 	/*
7903 	 * image activation may be failed due to policy
7904 	 * which is unexpected but security framework does not
7905 	 * approve of exec, kill and return immediately.
7906 	 */
7907 	if (imgp->ip_mac_return != 0) {
7908 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7909 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY, 0, 0);
7910 		signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
7911 		error = imgp->ip_mac_return;
7912 		unexpected_failure = TRUE;
7913 		goto done;
7914 	}
7915 
7916 	if (imgp->ip_cs_error != OS_REASON_NULL) {
7917 		signature_failure_reason = imgp->ip_cs_error;
7918 		imgp->ip_cs_error = OS_REASON_NULL;
7919 		error = EACCES;
7920 		goto done;
7921 	}
7922 
7923 	/* call the launch constraints hook */
7924 	os_reason_t launch_constraint_reason;
7925 	if ((error = mac_proc_check_launch_constraints(p, imgp, &launch_constraint_reason)) != 0) {
7926 		signature_failure_reason = launch_constraint_reason;
7927 		goto done;
7928 	}
7929 
7930 	/*
7931 	 * Reject when there's subsystem root path set, but the image is restricted, and doesn't require
7932 	 * library validation. This is to avoid subsystem root being used to inject unsigned code
7933 	 */
7934 	if (!allow_unrestricted_subsystem_root()) {
7935 		if ((imgp->ip_csflags & CS_RESTRICT || proc_issetugid(p)) &&
7936 		    !(imgp->ip_csflags & CS_REQUIRE_LV) &&
7937 		    (imgp->ip_subsystem_root_path != NULL)) {
7938 			signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
7939 			error = EACCES;
7940 			goto done;
7941 		}
7942 	}
7943 
7944 #if XNU_TARGET_OS_OSX
7945 	/* Check for platform passed in spawn attr if iOS binary is being spawned */
7946 	if (proc_platform(p) == PLATFORM_IOS) {
7947 		struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
7948 		if (psa == NULL || psa->psa_platform == 0) {
7949 			boolean_t no_sandbox_entitled = FALSE;
7950 #if DEBUG || DEVELOPMENT
7951 			/*
7952 			 * Allow iOS binaries to spawn on internal systems
7953 			 * if no-sandbox entitlement is present of unentitled_ios_sim_launch
7954 			 * boot-arg set to true
7955 			 */
7956 			if (unentitled_ios_sim_launch) {
7957 				no_sandbox_entitled = TRUE;
7958 			} else {
7959 				no_sandbox_entitled = IOVnodeHasEntitlement(imgp->ip_vp,
7960 				    (int64_t)imgp->ip_arch_offset, "com.apple.private.security.no-sandbox");
7961 			}
7962 #endif /* DEBUG || DEVELOPMENT */
7963 			if (!no_sandbox_entitled) {
7964 				signature_failure_reason = os_reason_create(OS_REASON_EXEC,
7965 				    EXEC_EXIT_REASON_WRONG_PLATFORM);
7966 				error = EACCES;
7967 				goto done;
7968 			}
7969 			printf("Allowing spawn of iOS binary %s since it has "
7970 			    "com.apple.private.security.no-sandbox entitlement or unentitled_ios_sim_launch "
7971 			    "boot-arg set to true\n", p->p_name);
7972 		} else if (psa->psa_platform != PLATFORM_IOS) {
7973 			/* Simulator binary spawned with wrong platform */
7974 			signature_failure_reason = os_reason_create(OS_REASON_EXEC,
7975 			    EXEC_EXIT_REASON_WRONG_PLATFORM);
7976 			error = EACCES;
7977 			goto done;
7978 		} else {
7979 			printf("Allowing spawn of iOS binary %s since correct platform was passed in spawn\n",
7980 			    p->p_name);
7981 		}
7982 	}
7983 #endif /* XNU_TARGET_OS_OSX */
7984 
7985 	/* If the code signature came through the image activation path, we skip the
7986 	 * taskgated / externally attached path. */
7987 	if (imgp->ip_csflags & CS_SIGNED) {
7988 		error = 0;
7989 		goto done;
7990 	}
7991 
7992 	/* The rest of the code is for signatures that either already have been externally
7993 	 * attached (likely, but not necessarily by a previous run through the taskgated
7994 	 * path), or that will now be attached by taskgated. */
7995 
7996 	kr = task_get_task_access_port(proc_task(p), &port);
7997 	if (KERN_SUCCESS != kr || !IPC_PORT_VALID(port)) {
7998 		error = 0;
7999 		if (require_success) {
8000 			KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
8001 			    proc_getpid(p), OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT, 0, 0);
8002 			signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT);
8003 			error = EACCES;
8004 		}
8005 		goto done;
8006 	}
8007 
8008 	/*
8009 	 * taskgated returns KERN_SUCCESS if it has completed its work
8010 	 * and the exec should continue, KERN_FAILURE if the exec should
8011 	 * fail, or it may error out with different error code in an
8012 	 * event of mig failure (e.g. process was signalled during the
8013 	 * rpc call, taskgated died, mig server died etc.).
8014 	 */
8015 
8016 	kr = __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(port, proc_getpid(p));
8017 	switch (kr) {
8018 	case KERN_SUCCESS:
8019 		error = 0;
8020 		break;
8021 	case KERN_FAILURE:
8022 		error = EACCES;
8023 
8024 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
8025 		    proc_getpid(p), OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG, 0, 0);
8026 		signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG);
8027 		goto done;
8028 	default:
8029 		error = EACCES;
8030 
8031 		KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
8032 		    proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER, 0, 0);
8033 		signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER);
8034 		unexpected_failure = TRUE;
8035 		goto done;
8036 	}
8037 
8038 	/* Only do this if exec_resettextvp() did not fail */
8039 	if (p->p_textvp != NULLVP) {
8040 		csb = ubc_cs_blob_get(p->p_textvp, -1, -1, p->p_textoff);
8041 
8042 		if (csb != NULL) {
8043 			/* As the enforcement we can do here is very limited, we only allow things that
8044 			 * are the only reason why this code path still exists:
8045 			 * Adhoc signed non-platform binaries without special cs_flags and without any
8046 			 * entitlements (unrestricted ones still pass AMFI). */
8047 			if (
8048 				/* Revalidate the blob if necessary through bumped generation count. */
8049 				(ubc_cs_generation_check(p->p_textvp) == 0 ||
8050 				ubc_cs_blob_revalidate(p->p_textvp, csb, imgp, 0, proc_platform(p)) == 0) &&
8051 				/* Only CS_ADHOC, no CS_KILL, CS_HARD etc. */
8052 				(csb->csb_flags & CS_ALLOWED_MACHO) == CS_ADHOC &&
8053 				/* If it has a CMS blob, it's not adhoc. The CS_ADHOC flag can lie. */
8054 				csblob_find_blob_bytes((const uint8_t *)csb->csb_mem_kaddr, csb->csb_mem_size,
8055 				CSSLOT_SIGNATURESLOT,
8056 				CSMAGIC_BLOBWRAPPER) == NULL &&
8057 				/* It could still be in a trust cache (unlikely with CS_ADHOC), or a magic path. */
8058 				csb->csb_platform_binary == 0 &&
8059 				/* No entitlements, not even unrestricted ones. */
8060 				csb->csb_entitlements_blob == NULL &&
8061 				csb->csb_der_entitlements_blob == NULL) {
8062 				proc_lock(p);
8063 				proc_csflags_set(p, CS_SIGNED | CS_VALID);
8064 				proc_unlock(p);
8065 			} else {
8066 				uint8_t cdhash[CS_CDHASH_LEN];
8067 				char cdhash_string[CS_CDHASH_STRING_SIZE];
8068 				proc_getcdhash(p, cdhash);
8069 				cdhash_to_string(cdhash_string, cdhash);
8070 				printf("ignoring detached code signature on '%s' with cdhash '%s' "
8071 				    "because it is invalid, or not a simple adhoc signature.\n",
8072 				    p->p_name, cdhash_string);
8073 			}
8074 		}
8075 	}
8076 
8077 done:
8078 	if (0 == error) {
8079 		/*
8080 		 * Update the new process's signature-dependent process state.
8081 		 * state.
8082 		 */
8083 
8084 		error = proc_process_signature(p, &signature_failure_reason);
8085 	}
8086 
8087 	if (0 == error) {
8088 		/*
8089 		 * Update the new main thread's signature-dependent thread
8090 		 * state. This was also called when the thread was created,
8091 		 * but for the main thread the signature was not yet attached
8092 		 * at that time.
8093 		 */
8094 		kr = thread_process_signature(imgp->ip_new_thread, proc_get_task_raw(p));
8095 
8096 		if (kr != KERN_SUCCESS) {
8097 			error = EINVAL;
8098 			signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MACHINE_THREAD);
8099 		}
8100 	}
8101 
8102 	if (0 == error) {
8103 		/* The process's code signature related properties are
8104 		 * fully set up, so this is an opportune moment to log
8105 		 * platform binary execution, if desired. */
8106 		if (platform_exec_logging != 0 && csproc_get_platform_binary(p)) {
8107 			uint8_t cdhash[CS_CDHASH_LEN];
8108 			char cdhash_string[CS_CDHASH_STRING_SIZE];
8109 			proc_getcdhash(p, cdhash);
8110 			cdhash_to_string(cdhash_string, cdhash);
8111 
8112 			os_log(peLog, "CS Platform Exec Logging: Executing platform signed binary "
8113 			    "'%s' with cdhash %s\n", p->p_name, cdhash_string);
8114 		}
8115 	} else {
8116 		if (!unexpected_failure) {
8117 			proc_csflags_set(p, CS_KILLED);
8118 		}
8119 		/* make very sure execution fails */
8120 		if (vfexec || spawn) {
8121 			assert(signature_failure_reason != OS_REASON_NULL);
8122 			psignal_vfork_with_reason(p, proc_task(p), imgp->ip_new_thread,
8123 			    SIGKILL, signature_failure_reason);
8124 			signature_failure_reason = OS_REASON_NULL;
8125 			error = 0;
8126 		} else {
8127 			assert(signature_failure_reason != OS_REASON_NULL);
8128 			psignal_with_reason(p, SIGKILL, signature_failure_reason);
8129 			signature_failure_reason = OS_REASON_NULL;
8130 		}
8131 	}
8132 
8133 	if (port != IPC_PORT_NULL) {
8134 		ipc_port_release_send(port);
8135 	}
8136 
8137 	/* If we hit this, we likely would have leaked an exit reason */
8138 	assert(signature_failure_reason == OS_REASON_NULL);
8139 	return error;
8140 }
8141 
8142 /*
8143  * Typically as soon as we start executing this process, the
8144  * first instruction will trigger a VM fault to bring the text
8145  * pages (as executable) into the address space, followed soon
8146  * thereafter by dyld data structures (for dynamic executable).
8147  * To optimize this, as well as improve support for hardware
8148  * debuggers that can only access resident pages present
8149  * in the process' page tables, we prefault some pages if
8150  * possible. Errors are non-fatal.
8151  */
8152 #ifndef PREVENT_CALLER_STACK_USE
8153 #define PREVENT_CALLER_STACK_USE __attribute__((noinline))
8154 #endif
8155 
8156 /*
8157  * Prefaulting dyld data does not work (rdar://76621401)
8158  */
8159 #define FIXED_76621401 0
8160 static void PREVENT_CALLER_STACK_USE
exec_prefault_data(__unused proc_t p,__unused struct image_params * imgp,__unused load_result_t * load_result)8161 exec_prefault_data(
8162 	__unused proc_t p,
8163 	__unused struct image_params *imgp,
8164 	__unused load_result_t *load_result)
8165 {
8166 #if FIXED_76621401
8167 	int ret;
8168 	size_t expected_all_image_infos_size;
8169 #endif /* FIXED_76621401 */
8170 	kern_return_t kr;
8171 
8172 	/*
8173 	 * Prefault executable or dyld entry point.
8174 	 */
8175 	if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
8176 		DEBUG4K_LOAD("entry_point 0x%llx\n", (uint64_t)load_result->entry_point);
8177 	}
8178 	kr = vm_fault(current_map(),
8179 	    vm_map_trunc_page(load_result->entry_point,
8180 	    vm_map_page_mask(current_map())),
8181 	    VM_PROT_READ | VM_PROT_EXECUTE,
8182 	    FALSE, VM_KERN_MEMORY_NONE,
8183 	    THREAD_UNINT, NULL, 0);
8184 	if (kr != KERN_SUCCESS) {
8185 		DEBUG4K_ERROR("map %p va 0x%llx -> 0x%x\n", current_map(), (uint64_t)vm_map_trunc_page(load_result->entry_point, vm_map_page_mask(current_map())), kr);
8186 	}
8187 
8188 #if FIXED_76621401
8189 	if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
8190 		expected_all_image_infos_size = sizeof(struct user64_dyld_all_image_infos);
8191 	} else {
8192 		expected_all_image_infos_size = sizeof(struct user32_dyld_all_image_infos);
8193 	}
8194 
8195 	/* Decode dyld anchor structure from <mach-o/dyld_images.h> */
8196 	if (load_result->dynlinker &&
8197 	    load_result->all_image_info_addr &&
8198 	    load_result->all_image_info_size >= expected_all_image_infos_size) {
8199 		union {
8200 			struct user64_dyld_all_image_infos      infos64;
8201 			struct user32_dyld_all_image_infos      infos32;
8202 		} all_image_infos;
8203 
8204 		/*
8205 		 * Pre-fault to avoid copyin() going through the trap handler
8206 		 * and recovery path.
8207 		 */
8208 		if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
8209 			DEBUG4K_LOAD("all_image_info_addr 0x%llx\n", load_result->all_image_info_addr);
8210 		}
8211 		kr = vm_fault(current_map(),
8212 		    vm_map_trunc_page(load_result->all_image_info_addr,
8213 		    vm_map_page_mask(current_map())),
8214 		    VM_PROT_READ | VM_PROT_WRITE,
8215 		    FALSE, VM_KERN_MEMORY_NONE,
8216 		    THREAD_UNINT, NULL, 0);
8217 		if (kr != KERN_SUCCESS) {
8218 //			printf("%s:%d map %p va 0x%llx -> 0x%x\n", __FUNCTION__, __LINE__, current_map(), vm_map_trunc_page(load_result->all_image_info_addr, vm_map_page_mask(current_map())), kr);
8219 		}
8220 		if ((load_result->all_image_info_addr & PAGE_MASK) + expected_all_image_infos_size > PAGE_SIZE) {
8221 			/* all_image_infos straddles a page */
8222 			kr = vm_fault(current_map(),
8223 			    vm_map_trunc_page(load_result->all_image_info_addr + expected_all_image_infos_size - 1,
8224 			    vm_map_page_mask(current_map())),
8225 			    VM_PROT_READ | VM_PROT_WRITE,
8226 			    FALSE, VM_KERN_MEMORY_NONE,
8227 			    THREAD_UNINT, NULL, 0);
8228 			if (kr != KERN_SUCCESS) {
8229 //				printf("%s:%d map %p va 0x%llx -> 0x%x\n", __FUNCTION__, __LINE__, current_map(), vm_map_trunc_page(load_result->all_image_info_addr + expected_all_image_infos_size -1, vm_map_page_mask(current_map())), kr);
8230 			}
8231 		}
8232 
8233 		if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
8234 			DEBUG4K_LOAD("copyin(0x%llx, 0x%lx)\n", load_result->all_image_info_addr, expected_all_image_infos_size);
8235 		}
8236 		ret = copyin((user_addr_t)load_result->all_image_info_addr,
8237 		    &all_image_infos,
8238 		    expected_all_image_infos_size);
8239 		if (ret == 0 && all_image_infos.infos32.version >= DYLD_ALL_IMAGE_INFOS_ADDRESS_MINIMUM_VERSION) {
8240 			user_addr_t notification_address;
8241 			user_addr_t dyld_image_address;
8242 			user_addr_t dyld_version_address;
8243 			user_addr_t dyld_all_image_infos_address;
8244 			user_addr_t dyld_slide_amount;
8245 
8246 			if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
8247 				notification_address = (user_addr_t)all_image_infos.infos64.notification;
8248 				dyld_image_address = (user_addr_t)all_image_infos.infos64.dyldImageLoadAddress;
8249 				dyld_version_address = (user_addr_t)all_image_infos.infos64.dyldVersion;
8250 				dyld_all_image_infos_address = (user_addr_t)all_image_infos.infos64.dyldAllImageInfosAddress;
8251 			} else {
8252 				notification_address = all_image_infos.infos32.notification;
8253 				dyld_image_address = all_image_infos.infos32.dyldImageLoadAddress;
8254 				dyld_version_address = all_image_infos.infos32.dyldVersion;
8255 				dyld_all_image_infos_address = all_image_infos.infos32.dyldAllImageInfosAddress;
8256 			}
8257 
8258 			/*
8259 			 * dyld statically sets up the all_image_infos in its Mach-O
8260 			 * binary at static link time, with pointers relative to its default
8261 			 * load address. Since ASLR might slide dyld before its first
8262 			 * instruction is executed, "dyld_slide_amount" tells us how far
8263 			 * dyld was loaded compared to its default expected load address.
8264 			 * All other pointers into dyld's image should be adjusted by this
8265 			 * amount. At some point later, dyld will fix up pointers to take
8266 			 * into account the slide, at which point the all_image_infos_address
8267 			 * field in the structure will match the runtime load address, and
8268 			 * "dyld_slide_amount" will be 0, if we were to consult it again.
8269 			 */
8270 
8271 			dyld_slide_amount = (user_addr_t)load_result->all_image_info_addr - dyld_all_image_infos_address;
8272 
8273 #if 0
8274 			kprintf("exec_prefault: 0x%016llx 0x%08x 0x%016llx 0x%016llx 0x%016llx 0x%016llx\n",
8275 			    (uint64_t)load_result->all_image_info_addr,
8276 			    all_image_infos.infos32.version,
8277 			    (uint64_t)notification_address,
8278 			    (uint64_t)dyld_image_address,
8279 			    (uint64_t)dyld_version_address,
8280 			    (uint64_t)dyld_all_image_infos_address);
8281 #endif
8282 
8283 			if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
8284 				DEBUG4K_LOAD("notification_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)notification_address, (uint64_t)dyld_slide_amount);
8285 			}
8286 			kr = vm_fault(current_map(),
8287 			    vm_map_trunc_page(notification_address + dyld_slide_amount,
8288 			    vm_map_page_mask(current_map())),
8289 			    VM_PROT_READ | VM_PROT_EXECUTE,
8290 			    FALSE, VM_KERN_MEMORY_NONE,
8291 			    THREAD_UNINT, NULL, 0);
8292 			if (kr != KERN_SUCCESS) {
8293 //				printf("%s:%d map %p va 0x%llx -> 0x%x\n", __FUNCTION__, __LINE__, current_map(), vm_map_trunc_page(notification_address + dyld_slide_amount, vm_map_page_mask(current_map())), kr);
8294 			}
8295 			if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
8296 				DEBUG4K_LOAD("dyld_image_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)dyld_image_address, (uint64_t)dyld_slide_amount);
8297 			}
8298 			kr = vm_fault(current_map(),
8299 			    vm_map_trunc_page(dyld_image_address + dyld_slide_amount,
8300 			    vm_map_page_mask(current_map())),
8301 			    VM_PROT_READ | VM_PROT_EXECUTE,
8302 			    FALSE, VM_KERN_MEMORY_NONE,
8303 			    THREAD_UNINT, NULL, 0);
8304 			if (kr != KERN_SUCCESS) {
8305 //				printf("%s:%d map %p va 0x%llx -> 0x%x\n", __FUNCTION__, __LINE__, current_map(), vm_map_trunc_page(dyld_image_address + dyld_slide_amount, vm_map_page_mask(current_map())), kr);
8306 			}
8307 			if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
8308 				DEBUG4K_LOAD("dyld_version_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)dyld_version_address, (uint64_t)dyld_slide_amount);
8309 			}
8310 			kr = vm_fault(current_map(),
8311 			    vm_map_trunc_page(dyld_version_address + dyld_slide_amount,
8312 			    vm_map_page_mask(current_map())),
8313 			    VM_PROT_READ,
8314 			    FALSE, VM_KERN_MEMORY_NONE,
8315 			    THREAD_UNINT, NULL, 0);
8316 			if (kr != KERN_SUCCESS) {
8317 //				printf("%s:%d map %p va 0x%llx -> 0x%x\n", __FUNCTION__, __LINE__, current_map(), vm_map_trunc_page(dyld_version_address + dyld_slide_amount, vm_map_page_mask(current_map())), kr);
8318 			}
8319 			if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
8320 				DEBUG4K_LOAD("dyld_all_image_infos_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)dyld_version_address, (uint64_t)dyld_slide_amount);
8321 			}
8322 			kr = vm_fault(current_map(),
8323 			    vm_map_trunc_page(dyld_all_image_infos_address + dyld_slide_amount,
8324 			    vm_map_page_mask(current_map())),
8325 			    VM_PROT_READ | VM_PROT_WRITE,
8326 			    FALSE, VM_KERN_MEMORY_NONE,
8327 			    THREAD_UNINT, NULL, 0);
8328 			if (kr != KERN_SUCCESS) {
8329 //				printf("%s:%d map %p va 0x%llx -> 0x%x\n", __FUNCTION__, __LINE__, current_map(), vm_map_trunc_page(dyld_all_image_infos_address + dyld_slide_amount, vm_map_page_mask(current_map())), kr);
8330 			}
8331 		}
8332 	}
8333 #endif /* FIXED_76621401 */
8334 }
8335 
8336 static int
8337 sysctl_libmalloc_experiments SYSCTL_HANDLER_ARGS
8338 {
8339 #pragma unused(oidp, arg2, req)
8340 	int changed;
8341 	errno_t error;
8342 	uint64_t value = os_atomic_load_wide(&libmalloc_experiment_factors, relaxed);
8343 
8344 	error = sysctl_io_number(req, value, sizeof(value), &value, &changed);
8345 	if (error) {
8346 		return error;
8347 	}
8348 
8349 	if (changed) {
8350 		os_atomic_store_wide(&libmalloc_experiment_factors, value, relaxed);
8351 	}
8352 
8353 	return 0;
8354 }
8355 
8356 EXPERIMENT_FACTOR_LEGACY_PROC(_kern, libmalloc_experiments, CTLTYPE_QUAD | CTLFLAG_RW, 0, 0, &sysctl_libmalloc_experiments, "A", "");
8357 
8358 SYSCTL_NODE(_kern, OID_AUTO, sec_transition,
8359     CTLFLAG_RD | CTLFLAG_LOCKED, 0, "sec_transition");
8360 
8361 #if DEBUG || DEVELOPMENT
8362 static int
sysctl_setup_ensure_pidversion_changes_on_exec(__unused int64_t in,int64_t * out)8363 sysctl_setup_ensure_pidversion_changes_on_exec(__unused int64_t in, int64_t *out)
8364 {
8365 	// Tweak nextpidversion to try to trigger a reuse (unless the exec code is doing the right thing)
8366 	int current_pid_version = proc_get_ro(current_proc())->p_idversion;
8367 	nextpidversion = current_pid_version;
8368 	*out = 0;
8369 	return KERN_SUCCESS;
8370 }
8371 
8372 SYSCTL_TEST_REGISTER(setup_ensure_pidversion_changes_on_exec, sysctl_setup_ensure_pidversion_changes_on_exec);
8373 #endif /* DEBUG || DEVELOPMENT */
8374