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/sysproto.h>
106 #include <sys/sysctl.h>
107 #include <sys/persona.h>
108 #include <sys/reason.h>
109 #if SYSV_SHM
110 #include <sys/shm_internal.h> /* shmexec() */
111 #endif
112 #include <sys/ubc_internal.h> /* ubc_map() */
113 #include <sys/spawn.h>
114 #include <sys/spawn_internal.h>
115 #include <sys/process_policy.h>
116 #include <sys/codesign.h>
117 #include <sys/random.h>
118 #include <crypto/sha1.h>
119
120 #include <libkern/libkern.h>
121 #include <libkern/crypto/sha2.h>
122 #include <security/audit/audit.h>
123
124 #include <ipc/ipc_types.h>
125
126 #include <mach/mach_param.h>
127 #include <mach/mach_types.h>
128 #include <mach/port.h>
129 #include <mach/task.h>
130 #include <mach/task_access.h>
131 #include <mach/thread_act.h>
132 #include <mach/vm_map.h>
133 #include <mach/mach_vm.h>
134 #include <mach/vm_param.h>
135 #include <mach_debug/mach_debug_types.h>
136
137 #include <kern/sched_prim.h> /* thread_wakeup() */
138 #include <kern/affinity.h>
139 #include <kern/assert.h>
140 #include <kern/task.h>
141 #include <kern/thread.h>
142 #include <kern/coalition.h>
143 #include <kern/policy_internal.h>
144 #include <kern/kalloc.h>
145 #include <kern/zalloc.h> /* zone_userspace_reboot_checks() */
146
147 #include <os/log.h>
148
149 #if CONFIG_MACF
150 #include <security/mac_framework.h>
151 #include <security/mac_mach_internal.h>
152 #endif
153
154 #if CONFIG_AUDIT
155 #include <bsm/audit_kevents.h>
156 #endif
157
158 #if CONFIG_ARCADE
159 #include <kern/arcade.h>
160 #endif
161
162 #include <vm/vm_map.h>
163 #include <vm/vm_kern.h>
164 #include <vm/vm_protos.h>
165 #include <vm/vm_kern.h>
166 #include <vm/vm_fault.h>
167 #include <vm/vm_pageout.h>
168 #include <vm/pmap.h>
169
170 #include <kdp/kdp_dyld.h>
171
172 #include <machine/machine_routines.h>
173 #include <machine/pal_routines.h>
174
175 #include <pexpert/pexpert.h>
176
177 #if CONFIG_MEMORYSTATUS
178 #include <sys/kern_memorystatus.h>
179 #endif
180
181 #include <IOKit/IOBSD.h>
182 #include <IOKit/IOPlatformExpert.h>
183
184 #include "kern_exec_internal.h"
185
186 extern boolean_t vm_darkwake_mode;
187
188 /* enable crash reports on various exec failures */
189 static TUNABLE(bool, bootarg_execfailurereports, "execfailurecrashes", false);
190
191 #if XNU_TARGET_OS_OSX
192 #if __has_feature(ptrauth_calls)
193 static TUNABLE(bool, bootarg_arm64e_preview_abi, "-arm64e_preview_abi", false);
194 #endif /* __has_feature(ptrauth_calls) */
195
196 #if DEBUG || DEVELOPMENT
197 static TUNABLE(bool, unentitled_ios_sim_launch, "unentitled_ios_sim_launch", false);
198 #endif /* DEBUG || DEVELOPMENT */
199 #endif /* XNU_TARGET_OS_OSX */
200
201 #if CONFIG_DTRACE
202 /* Do not include dtrace.h, it redefines kmem_[alloc/free] */
203 extern void dtrace_proc_exec(proc_t);
204 extern void (*dtrace_proc_waitfor_exec_ptr)(proc_t);
205
206 /*
207 * Since dtrace_proc_waitfor_exec_ptr can be added/removed in dtrace_subr.c,
208 * we will store its value before actually calling it.
209 */
210 static void (*dtrace_proc_waitfor_hook)(proc_t) = NULL;
211
212 #include <sys/dtrace_ptss.h>
213 #endif
214
215 #if __has_feature(ptrauth_calls)
216 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_per_team_id,
217 "vm_shared_region_per_team_id", 1);
218 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_by_entitlement,
219 "vm_shared_region_by_entitlement", 1);
220
221 /* Upon userland request, reslide the shared cache. */
222 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_aslr,
223 "vm_shared_region_reslide_aslr",
224 #if CONFIG_RESLIDE_SHARED_CACHE
225 1
226 #else
227 0
228 #endif /* CONFIG_RESLIDE_SHARED_CACHE */
229 );
230
231 /*
232 * Flag to control what processes should get shared cache randomize resliding
233 * after a fault in the shared cache region:
234 *
235 * 0 - all processes get a new randomized slide
236 * 1 - only platform processes get a new randomized slide
237 */
238 TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_restrict,
239 "vm_shared_region_reslide_restrict", 1);
240
241 #if DEVELOPMENT || DEBUG
242 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_per_team_id,
243 CTLFLAG_RW, &vm_shared_region_per_team_id, 0, "");
244 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_by_entitlement,
245 CTLFLAG_RW, &vm_shared_region_by_entitlement, 0, "");
246 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_restrict,
247 CTLFLAG_RW, &vm_shared_region_reslide_restrict, 0, "");
248 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_aslr,
249 CTLFLAG_RW, &vm_shared_region_reslide_aslr, 0, "");
250 #endif
251 #endif /* __has_feature(ptrauth_calls) */
252
253 #if DEVELOPMENT || DEBUG
254 static TUNABLE(bool, enable_dext_coredumps_on_panic, "dext_panic_coredump", true);
255 #else
256 static TUNABLE(bool, enable_dext_coredumps_on_panic, "dext_panic_coredump", false);
257 #endif
258 extern kern_return_t kern_register_userspace_coredump(task_t task, const char * name);
259 #define USERSPACE_COREDUMP_PANIC_ENTITLEMENT "com.apple.private.enable-coredump-on-panic"
260 #define USERSPACE_COREDUMP_PANIC_SEED_ENTITLEMENT \
261 "com.apple.private.enable-coredump-on-panic-seed-privacy-approved"
262
263 extern void proc_apply_task_networkbg_internal(proc_t, thread_t);
264 extern void task_set_did_exec_flag(task_t task);
265 extern void task_clear_exec_copy_flag(task_t task);
266 proc_t proc_exec_switch_task(proc_t old_proc, proc_t new_proc, task_t old_task,
267 task_t new_task, thread_t new_thread, void **inherit);
268 boolean_t task_is_active(task_t);
269 boolean_t thread_is_active(thread_t thread);
270 void thread_copy_resource_info(thread_t dst_thread, thread_t src_thread);
271 void *ipc_importance_exec_switch_task(task_t old_task, task_t new_task);
272 extern void ipc_importance_release(void *elem);
273 extern boolean_t task_has_watchports(task_t task);
274 extern void task_set_no_smt(task_t task);
275 #if defined(HAS_APPLE_PAC)
276 char *task_get_vm_shared_region_id_and_jop_pid(task_t task, uint64_t *jop_pid);
277 #endif
278 task_t convert_port_to_task(ipc_port_t port);
279
280 /*
281 * Mach things for which prototypes are unavailable from Mach headers
282 */
283 #define IPC_OBJECT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND 0x1
284 void ipc_task_enable(
285 task_t task);
286 void ipc_task_reset(
287 task_t task);
288 void ipc_thread_reset(
289 thread_t thread);
290 kern_return_t ipc_object_copyin(
291 ipc_space_t space,
292 mach_port_name_t name,
293 mach_msg_type_name_t msgt_name,
294 ipc_object_t *objectp,
295 mach_port_context_t context,
296 mach_msg_guard_flags_t *guard_flags,
297 uint32_t kmsg_flags);
298 void ipc_port_release_send(ipc_port_t);
299
300 #if DEVELOPMENT || DEBUG
301 void task_importance_update_owner_info(task_t);
302 #endif
303
304 extern struct savearea *get_user_regs(thread_t);
305
306 __attribute__((noinline)) int __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid);
307
308 #include <kern/thread.h>
309 #include <kern/task.h>
310 #include <kern/ast.h>
311 #include <kern/mach_loader.h>
312 #include <kern/mach_fat.h>
313 #include <mach-o/fat.h>
314 #include <mach-o/loader.h>
315 #include <machine/vmparam.h>
316 #include <sys/imgact.h>
317
318 #include <sys/sdt.h>
319
320
321 /*
322 * EAI_ITERLIMIT The maximum number of times to iterate an image
323 * activator in exec_activate_image() before treating
324 * it as malformed/corrupt.
325 */
326 #define EAI_ITERLIMIT 3
327
328 /*
329 * For #! interpreter parsing
330 */
331 #define IS_WHITESPACE(ch) ((ch == ' ') || (ch == '\t'))
332 #define IS_EOL(ch) ((ch == '#') || (ch == '\n'))
333
334 extern vm_map_t bsd_pageable_map;
335 extern const struct fileops vnops;
336 extern int nextpidversion;
337
338
339 #define USER_ADDR_ALIGN(addr, val) \
340 ( ( (user_addr_t)(addr) + (val) - 1) \
341 & ~((val) - 1) )
342
343 /*
344 * For subsystem root support
345 */
346 #define SPAWN_SUBSYSTEM_ROOT_ENTITLEMENT "com.apple.private.spawn-subsystem-root"
347
348 /*
349 * Allow setting p_crash_behavior to trigger panic on crash
350 */
351 #define SPAWN_SET_PANIC_CRASH_BEHAVIOR "com.apple.private.spawn-panic-crash-behavior"
352
353 /* Platform Code Exec Logging */
354 static int platform_exec_logging = 0;
355
356 SYSCTL_DECL(_security_mac);
357
358 SYSCTL_INT(_security_mac, OID_AUTO, platform_exec_logging, CTLFLAG_RW, &platform_exec_logging, 0,
359 "log cdhashes for all platform binary executions");
360
361 static os_log_t peLog = OS_LOG_DEFAULT;
362
363 struct exec_port_actions {
364 uint32_t portwatch_count;
365 uint32_t registered_count;
366 ipc_port_t *portwatch_array;
367 ipc_port_t *registered_array;
368 };
369
370 struct image_params; /* Forward */
371 static int exec_activate_image(struct image_params *imgp);
372 static int exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp);
373 static int load_return_to_errno(load_return_t lrtn);
374 static int execargs_alloc(struct image_params *imgp);
375 static int execargs_free(struct image_params *imgp);
376 static int exec_check_permissions(struct image_params *imgp);
377 static int exec_extract_strings(struct image_params *imgp);
378 static int exec_add_apple_strings(struct image_params *imgp, const load_result_t *load_result);
379 static int exec_handle_sugid(struct image_params *imgp);
380 static int sugid_scripts = 0;
381 SYSCTL_INT(_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW | CTLFLAG_LOCKED, &sugid_scripts, 0, "");
382 static kern_return_t create_unix_stack(vm_map_t map, load_result_t* load_result, proc_t p);
383 static int copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size);
384 static void exec_resettextvp(proc_t, struct image_params *);
385 static int process_signature(proc_t, struct image_params *);
386 static void exec_prefault_data(proc_t, struct image_params *, load_result_t *);
387 static errno_t exec_handle_port_actions(struct image_params *imgp,
388 struct exec_port_actions *port_actions);
389 static errno_t exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
390 task_role_t psa_darwin_role, struct exec_port_actions *port_actions);
391 static void exec_port_actions_destroy(struct exec_port_actions *port_actions);
392
393 /*
394 * exec_add_user_string
395 *
396 * Add the requested string to the string space area.
397 *
398 * Parameters; struct image_params * image parameter block
399 * user_addr_t string to add to strings area
400 * int segment from which string comes
401 * boolean_t TRUE if string contributes to NCARGS
402 *
403 * Returns: 0 Success
404 * !0 Failure errno from copyinstr()
405 *
406 * Implicit returns:
407 * (imgp->ip_strendp) updated location of next add, if any
408 * (imgp->ip_strspace) updated byte count of space remaining
409 * (imgp->ip_argspace) updated byte count of space in NCARGS
410 */
411 __attribute__((noinline))
412 static int
exec_add_user_string(struct image_params * imgp,user_addr_t str,int seg,boolean_t is_ncargs)413 exec_add_user_string(struct image_params *imgp, user_addr_t str, int seg, boolean_t is_ncargs)
414 {
415 int error = 0;
416
417 do {
418 size_t len = 0;
419 int space;
420
421 if (is_ncargs) {
422 space = imgp->ip_argspace; /* by definition smaller than ip_strspace */
423 } else {
424 space = imgp->ip_strspace;
425 }
426
427 if (space <= 0) {
428 error = E2BIG;
429 break;
430 }
431
432 if (!UIO_SEG_IS_USER_SPACE(seg)) {
433 char *kstr = CAST_DOWN(char *, str); /* SAFE */
434 error = copystr(kstr, imgp->ip_strendp, space, &len);
435 } else {
436 error = copyinstr(str, imgp->ip_strendp, space, &len);
437 }
438
439 imgp->ip_strendp += len;
440 imgp->ip_strspace -= len;
441 if (is_ncargs) {
442 imgp->ip_argspace -= len;
443 }
444 } while (error == ENAMETOOLONG);
445
446 return error;
447 }
448
449 /*
450 * dyld is now passed the executable path as a getenv-like variable
451 * in the same fashion as the stack_guard and malloc_entropy keys.
452 */
453 #define EXECUTABLE_KEY "executable_path="
454
455 /*
456 * exec_save_path
457 *
458 * To support new app package launching for Mac OS X, the dyld needs the
459 * first argument to execve() stored on the user stack.
460 *
461 * Save the executable path name at the bottom of the strings area and set
462 * the argument vector pointer to the location following that to indicate
463 * the start of the argument and environment tuples, setting the remaining
464 * string space count to the size of the string area minus the path length.
465 *
466 * Parameters; struct image_params * image parameter block
467 * char * path used to invoke program
468 * int segment from which path comes
469 *
470 * Returns: int 0 Success
471 * EFAULT Bad address
472 * copy[in]str:EFAULT Bad address
473 * copy[in]str:ENAMETOOLONG Filename too long
474 *
475 * Implicit returns:
476 * (imgp->ip_strings) saved path
477 * (imgp->ip_strspace) space remaining in ip_strings
478 * (imgp->ip_strendp) start of remaining copy area
479 * (imgp->ip_argspace) space remaining of NCARGS
480 * (imgp->ip_applec) Initial applev[0]
481 *
482 * Note: We have to do this before the initial namei() since in the
483 * path contains symbolic links, namei() will overwrite the
484 * original path buffer contents. If the last symbolic link
485 * resolved was a relative pathname, we would lose the original
486 * "path", which could be an absolute pathname. This might be
487 * unacceptable for dyld.
488 */
489 static int
exec_save_path(struct image_params * imgp,user_addr_t path,int seg,const char ** excpath)490 exec_save_path(struct image_params *imgp, user_addr_t path, int seg, const char **excpath)
491 {
492 int error;
493 size_t len;
494 char *kpath;
495
496 // imgp->ip_strings can come out of a cache, so we need to obliterate the
497 // old path.
498 memset(imgp->ip_strings, '\0', strlen(EXECUTABLE_KEY) + MAXPATHLEN);
499
500 len = MIN(MAXPATHLEN, imgp->ip_strspace);
501
502 switch (seg) {
503 case UIO_USERSPACE32:
504 case UIO_USERSPACE64: /* Same for copyin()... */
505 error = copyinstr(path, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
506 break;
507 case UIO_SYSSPACE:
508 kpath = CAST_DOWN(char *, path); /* SAFE */
509 error = copystr(kpath, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
510 break;
511 default:
512 error = EFAULT;
513 break;
514 }
515
516 if (!error) {
517 bcopy(EXECUTABLE_KEY, imgp->ip_strings, strlen(EXECUTABLE_KEY));
518 len += strlen(EXECUTABLE_KEY);
519
520 imgp->ip_strendp += len;
521 imgp->ip_strspace -= len;
522
523 if (excpath) {
524 *excpath = imgp->ip_strings + strlen(EXECUTABLE_KEY);
525 }
526 }
527
528 return error;
529 }
530
531 /*
532 * exec_reset_save_path
533 *
534 * If we detect a shell script, we need to reset the string area
535 * state so that the interpreter can be saved onto the stack.
536 *
537 * Parameters; struct image_params * image parameter block
538 *
539 * Returns: int 0 Success
540 *
541 * Implicit returns:
542 * (imgp->ip_strings) saved path
543 * (imgp->ip_strspace) space remaining in ip_strings
544 * (imgp->ip_strendp) start of remaining copy area
545 * (imgp->ip_argspace) space remaining of NCARGS
546 *
547 */
548 static int
exec_reset_save_path(struct image_params * imgp)549 exec_reset_save_path(struct image_params *imgp)
550 {
551 imgp->ip_strendp = imgp->ip_strings;
552 imgp->ip_argspace = NCARGS;
553 imgp->ip_strspace = (NCARGS + PAGE_SIZE);
554
555 return 0;
556 }
557
558 /*
559 * exec_shell_imgact
560 *
561 * Image activator for interpreter scripts. If the image begins with
562 * the characters "#!", then it is an interpreter script. Verify the
563 * length of the script line indicating the interpreter is not in
564 * excess of the maximum allowed size. If this is the case, then
565 * break out the arguments, if any, which are separated by white
566 * space, and copy them into the argument save area as if they were
567 * provided on the command line before all other arguments. The line
568 * ends when we encounter a comment character ('#') or newline.
569 *
570 * Parameters; struct image_params * image parameter block
571 *
572 * Returns: -1 not an interpreter (keep looking)
573 * -3 Success: interpreter: relookup
574 * >0 Failure: interpreter: error number
575 *
576 * A return value other than -1 indicates subsequent image activators should
577 * not be given the opportunity to attempt to activate the image.
578 */
579 static int
exec_shell_imgact(struct image_params * imgp)580 exec_shell_imgact(struct image_params *imgp)
581 {
582 char *vdata = imgp->ip_vdata;
583 char *ihp;
584 char *line_startp, *line_endp;
585 char *interp;
586
587 /*
588 * Make sure it's a shell script. If we've already redirected
589 * from an interpreted file once, don't do it again.
590 */
591 if (vdata[0] != '#' ||
592 vdata[1] != '!' ||
593 (imgp->ip_flags & IMGPF_INTERPRET) != 0) {
594 return -1;
595 }
596
597 if (imgp->ip_origcputype != 0) {
598 /* Fat header previously matched, don't allow shell script inside */
599 return -1;
600 }
601
602 imgp->ip_flags |= IMGPF_INTERPRET;
603 imgp->ip_interp_sugid_fd = -1;
604 imgp->ip_interp_buffer[0] = '\0';
605
606 /* Check to see if SUGID scripts are permitted. If they aren't then
607 * clear the SUGID bits.
608 * imgp->ip_vattr is known to be valid.
609 */
610 if (sugid_scripts == 0) {
611 imgp->ip_origvattr->va_mode &= ~(VSUID | VSGID);
612 }
613
614 /* Try to find the first non-whitespace character */
615 for (ihp = &vdata[2]; ihp < &vdata[IMG_SHSIZE]; ihp++) {
616 if (IS_EOL(*ihp)) {
617 /* Did not find interpreter, "#!\n" */
618 return ENOEXEC;
619 } else if (IS_WHITESPACE(*ihp)) {
620 /* Whitespace, like "#! /bin/sh\n", keep going. */
621 } else {
622 /* Found start of interpreter */
623 break;
624 }
625 }
626
627 if (ihp == &vdata[IMG_SHSIZE]) {
628 /* All whitespace, like "#! " */
629 return ENOEXEC;
630 }
631
632 line_startp = ihp;
633
634 /* Try to find the end of the interpreter+args string */
635 for (; ihp < &vdata[IMG_SHSIZE]; ihp++) {
636 if (IS_EOL(*ihp)) {
637 /* Got it */
638 break;
639 } else {
640 /* Still part of interpreter or args */
641 }
642 }
643
644 if (ihp == &vdata[IMG_SHSIZE]) {
645 /* A long line, like "#! blah blah blah" without end */
646 return ENOEXEC;
647 }
648
649 /* Backtrack until we find the last non-whitespace */
650 while (IS_EOL(*ihp) || IS_WHITESPACE(*ihp)) {
651 ihp--;
652 }
653
654 /* The character after the last non-whitespace is our logical end of line */
655 line_endp = ihp + 1;
656
657 /*
658 * Now we have pointers to the usable part of:
659 *
660 * "#! /usr/bin/int first second third \n"
661 * ^ line_startp ^ line_endp
662 */
663
664 /* copy the interpreter name */
665 interp = imgp->ip_interp_buffer;
666 for (ihp = line_startp; (ihp < line_endp) && !IS_WHITESPACE(*ihp); ihp++) {
667 *interp++ = *ihp;
668 }
669 *interp = '\0';
670
671 exec_reset_save_path(imgp);
672 exec_save_path(imgp, CAST_USER_ADDR_T(imgp->ip_interp_buffer),
673 UIO_SYSSPACE, NULL);
674
675 /* Copy the entire interpreter + args for later processing into argv[] */
676 interp = imgp->ip_interp_buffer;
677 for (ihp = line_startp; (ihp < line_endp); ihp++) {
678 *interp++ = *ihp;
679 }
680 *interp = '\0';
681
682 #if CONFIG_SETUID
683 /*
684 * If we have an SUID or SGID script, create a file descriptor
685 * from the vnode and pass /dev/fd/%d instead of the actual
686 * path name so that the script does not get opened twice
687 */
688 if (imgp->ip_origvattr->va_mode & (VSUID | VSGID)) {
689 proc_t p;
690 struct fileproc *fp;
691 int fd;
692 int error;
693
694 p = vfs_context_proc(imgp->ip_vfs_context);
695 error = falloc(p, &fp, &fd, imgp->ip_vfs_context);
696 if (error) {
697 return error;
698 }
699
700 fp->fp_glob->fg_flag = FREAD;
701 fp->fp_glob->fg_ops = &vnops;
702 fp_set_data(fp, imgp->ip_vp);
703
704 proc_fdlock(p);
705 procfdtbl_releasefd(p, fd, NULL);
706 fp_drop(p, fd, fp, 1);
707 proc_fdunlock(p);
708 vnode_ref(imgp->ip_vp);
709
710 imgp->ip_interp_sugid_fd = fd;
711 }
712 #endif /* CONFIG_SETUID */
713
714 return -3;
715 }
716
717
718
719 /*
720 * exec_fat_imgact
721 *
722 * Image activator for fat 1.0 binaries. If the binary is fat, then we
723 * need to select an image from it internally, and make that the image
724 * we are going to attempt to execute. At present, this consists of
725 * reloading the first page for the image with a first page from the
726 * offset location indicated by the fat header.
727 *
728 * Parameters; struct image_params * image parameter block
729 *
730 * Returns: -1 not a fat binary (keep looking)
731 * -2 Success: encapsulated binary: reread
732 * >0 Failure: error number
733 *
734 * Important: This image activator is byte order neutral.
735 *
736 * Note: A return value other than -1 indicates subsequent image
737 * activators should not be given the opportunity to attempt
738 * to activate the image.
739 *
740 * If we find an encapsulated binary, we make no assertions
741 * about its validity; instead, we leave that up to a rescan
742 * for an activator to claim it, and, if it is claimed by one,
743 * that activator is responsible for determining validity.
744 */
745 static int
exec_fat_imgact(struct image_params * imgp)746 exec_fat_imgact(struct image_params *imgp)
747 {
748 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
749 kauth_cred_t cred = kauth_cred_proc_ref(p);
750 struct fat_header *fat_header = (struct fat_header *)imgp->ip_vdata;
751 struct _posix_spawnattr *psa = NULL;
752 struct fat_arch fat_arch;
753 int resid, error;
754 load_return_t lret;
755
756 if (imgp->ip_origcputype != 0) {
757 /* Fat header previously matched, don't allow another fat file inside */
758 error = -1; /* not claimed */
759 goto bad;
760 }
761
762 /* Make sure it's a fat binary */
763 if (OSSwapBigToHostInt32(fat_header->magic) != FAT_MAGIC) {
764 error = -1; /* not claimed */
765 goto bad;
766 }
767
768 /* imgp->ip_vdata has PAGE_SIZE, zerofilled if the file is smaller */
769 lret = fatfile_validate_fatarches((vm_offset_t)fat_header, PAGE_SIZE,
770 (off_t)imgp->ip_vattr->va_data_size);
771 if (lret != LOAD_SUCCESS) {
772 error = load_return_to_errno(lret);
773 goto bad;
774 }
775
776 /* If posix_spawn binprefs exist, respect those prefs. */
777 psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
778 if (psa != NULL && psa->psa_binprefs[0] != 0) {
779 uint32_t pr = 0;
780
781 /* Check each preference listed against all arches in header */
782 for (pr = 0; pr < NBINPREFS; pr++) {
783 cpu_type_t pref = psa->psa_binprefs[pr];
784 cpu_type_t subpref = psa->psa_subcpuprefs[pr];
785
786 if (pref == 0) {
787 /* No suitable arch in the pref list */
788 error = EBADARCH;
789 goto bad;
790 }
791
792 if (pref == CPU_TYPE_ANY) {
793 /* Fall through to regular grading */
794 goto regular_grading;
795 }
796
797 lret = fatfile_getbestarch_for_cputype(pref,
798 subpref,
799 (vm_offset_t)fat_header,
800 PAGE_SIZE,
801 imgp,
802 &fat_arch);
803 if (lret == LOAD_SUCCESS) {
804 goto use_arch;
805 }
806 }
807
808 /* Requested binary preference was not honored */
809 error = EBADEXEC;
810 goto bad;
811 }
812
813 regular_grading:
814 /* Look up our preferred architecture in the fat file. */
815 lret = fatfile_getbestarch((vm_offset_t)fat_header,
816 PAGE_SIZE,
817 imgp,
818 &fat_arch,
819 (p->p_flag & P_AFFINITY) != 0);
820 if (lret != LOAD_SUCCESS) {
821 error = load_return_to_errno(lret);
822 goto bad;
823 }
824
825 use_arch:
826 /* Read the Mach-O header out of fat_arch */
827 error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata,
828 PAGE_SIZE, fat_arch.offset,
829 UIO_SYSSPACE, (IO_UNIT | IO_NODELOCKED),
830 cred, &resid, p);
831 if (error) {
832 goto bad;
833 }
834
835 if (resid) {
836 memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
837 }
838
839 /* Success. Indicate we have identified an encapsulated binary */
840 error = -2;
841 imgp->ip_arch_offset = (user_size_t)fat_arch.offset;
842 imgp->ip_arch_size = (user_size_t)fat_arch.size;
843 imgp->ip_origcputype = fat_arch.cputype;
844 imgp->ip_origcpusubtype = fat_arch.cpusubtype;
845
846 bad:
847 kauth_cred_unref(&cred);
848 return error;
849 }
850
851 static int
activate_exec_state(task_t task,proc_t p,thread_t thread,load_result_t * result)852 activate_exec_state(task_t task, proc_t p, thread_t thread, load_result_t *result)
853 {
854 int ret;
855
856 (void)task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0);
857 task_set_64bit(task, result->is_64bit_addr, result->is_64bit_data);
858 if (result->is_64bit_addr) {
859 OSBitOrAtomic(P_LP64, &p->p_flag);
860 get_bsdthread_info(thread)->uu_flag |= UT_LP64;
861 } else {
862 OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag);
863 get_bsdthread_info(thread)->uu_flag &= ~UT_LP64;
864 }
865 task_set_mach_header_address(task, result->mach_header);
866
867 ret = thread_state_initialize(thread);
868 if (ret != KERN_SUCCESS) {
869 return ret;
870 }
871
872 if (result->threadstate) {
873 uint32_t *ts = result->threadstate;
874 uint32_t total_size = (uint32_t)result->threadstate_sz;
875
876 while (total_size > 0) {
877 uint32_t flavor = *ts++;
878 uint32_t size = *ts++;
879
880 ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
881 if (ret) {
882 return ret;
883 }
884 ts += size;
885 total_size -= (size + 2) * sizeof(uint32_t);
886 }
887 }
888
889 thread_setentrypoint(thread, result->entry_point);
890
891 return KERN_SUCCESS;
892 }
893
894 #if (DEVELOPMENT || DEBUG)
895 extern char panic_on_proc_crash[];
896 extern int use_panic_on_proc_crash;
897
898 extern char panic_on_proc_exit[];
899 extern int use_panic_on_proc_exit;
900
901 extern char panic_on_proc_spawn_fail[];
902 extern int use_panic_on_proc_spawn_fail;
903 #endif
904
905 void
set_proc_name(struct image_params * imgp,proc_t p)906 set_proc_name(struct image_params *imgp, proc_t p)
907 {
908 int p_name_len = sizeof(p->p_name) - 1;
909
910 if (imgp->ip_ndp->ni_cnd.cn_namelen > p_name_len) {
911 imgp->ip_ndp->ni_cnd.cn_namelen = p_name_len;
912 }
913
914 bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_name,
915 (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
916 p->p_name[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
917
918 if (imgp->ip_ndp->ni_cnd.cn_namelen > MAXCOMLEN) {
919 imgp->ip_ndp->ni_cnd.cn_namelen = MAXCOMLEN;
920 }
921
922 bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_comm,
923 (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
924 p->p_comm[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
925
926 #if DEVELOPMENT || DEBUG
927 /*
928 * This happens during image activation, so the crash behavior flags from
929 * posix_spawn will have already been set. So we don't have to worry about
930 * this being overridden.
931 */
932 if (use_panic_on_proc_crash && strcmp(p->p_comm, panic_on_proc_crash) == 0) {
933 printf("will panic on proc crash: %s\n", p->p_comm);
934 p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_CRASH;
935 }
936
937 if (use_panic_on_proc_exit && strcmp(p->p_comm, panic_on_proc_exit) == 0) {
938 printf("will panic on proc exit: %s\n", p->p_comm);
939 p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_EXIT;
940 }
941
942 if (use_panic_on_proc_spawn_fail && strcmp(p->p_comm, panic_on_proc_spawn_fail) == 0) {
943 printf("will panic on proc spawn fail: %s\n", p->p_comm);
944 p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_SPAWN_FAIL;
945 }
946 #endif
947 }
948
949 #if __has_feature(ptrauth_calls)
950 /**
951 * Returns a team ID string that may be used to assign a shared region.
952 *
953 * Platform binaries do not have team IDs and will return NULL. Non-platform
954 * binaries without a team ID will be assigned an artificial team ID of ""
955 * (empty string) so that they will not be assigned to the default shared
956 * region.
957 *
958 * @param imgp image parameter block
959 * @return NULL if this is a platform binary, or an appropriate team ID string
960 * otherwise
961 */
962 static inline const char *
get_teamid_for_shared_region(struct image_params * imgp)963 get_teamid_for_shared_region(struct image_params *imgp)
964 {
965 assert(imgp->ip_vp != NULL);
966
967 const char *ret = csvnode_get_teamid(imgp->ip_vp, imgp->ip_arch_offset);
968 if (ret) {
969 return ret;
970 }
971
972 struct cs_blob *blob = csvnode_get_blob(imgp->ip_vp, imgp->ip_arch_offset);
973 if (csblob_get_platform_binary(blob)) {
974 return NULL;
975 } else {
976 static const char *NO_TEAM_ID = "";
977 return NO_TEAM_ID;
978 }
979 }
980
981 /**
982 * Determines whether ptrauth should be enabled for the provided arm64 CPU subtype.
983 *
984 * @param cpusubtype Mach-O style CPU subtype
985 * @return whether the CPU subtype matches arm64e with the current ptrauth ABI
986 */
987 static inline bool
arm64_cpusubtype_uses_ptrauth(cpu_subtype_t cpusubtype)988 arm64_cpusubtype_uses_ptrauth(cpu_subtype_t cpusubtype)
989 {
990 return (cpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
991 CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(cpusubtype) == CPU_SUBTYPE_ARM64_PTR_AUTH_CURRENT_VERSION;
992 }
993
994 #endif /* __has_feature(ptrauth_calls) */
995
996 /**
997 * Returns whether a type/subtype slice matches the requested
998 * type/subtype.
999 *
1000 * @param mask Bits to mask from the requested/tested cpu type
1001 * @param req_cpu Requested cpu type
1002 * @param req_subcpu Requested cpu subtype
1003 * @param test_cpu Tested slice cpu type
1004 * @param test_subcpu Tested slice cpu subtype
1005 */
1006 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)1007 binary_match(cpu_type_t mask, cpu_type_t req_cpu,
1008 cpu_subtype_t req_subcpu, cpu_type_t test_cpu,
1009 cpu_subtype_t test_subcpu)
1010 {
1011 if ((test_cpu & ~mask) != (req_cpu & ~mask)) {
1012 return FALSE;
1013 }
1014
1015 test_subcpu &= ~CPU_SUBTYPE_MASK;
1016 req_subcpu &= ~CPU_SUBTYPE_MASK;
1017
1018 if (test_subcpu != req_subcpu && req_subcpu != (CPU_SUBTYPE_ANY & ~CPU_SUBTYPE_MASK)) {
1019 return FALSE;
1020 }
1021
1022 return TRUE;
1023 }
1024
1025
1026 #define MIN_IOS_TPRO_SDK_VERSION 0x00100000
1027 #define MIN_OSX_TPRO_SDK_VERSION 0x000D0000
1028 #define MIN_TVOS_TPRO_SDK_VERSION 0x000D0000
1029 #define MIN_WATCHOS_TPRO_SDK_VERSION 0x00090000
1030 #define MIN_DRIVERKIT_TPRO_SDK_VERSION 0x00600000
1031
1032 static void
exec_setup_tpro(struct image_params __unused * imgp,load_result_t * load_result)1033 exec_setup_tpro(struct image_params __unused *imgp, load_result_t *load_result)
1034 {
1035 extern boolean_t xprr_tpro_enabled;
1036 uint32_t min_sdk_version = 0;
1037
1038 switch (load_result->ip_platform) {
1039 case PLATFORM_IOS:
1040 case PLATFORM_IOSSIMULATOR:
1041 case PLATFORM_MACCATALYST:
1042 min_sdk_version = MIN_IOS_TPRO_SDK_VERSION;
1043 break;
1044 case PLATFORM_MACOS:
1045 min_sdk_version = MIN_IOS_TPRO_SDK_VERSION;
1046 break;
1047 case PLATFORM_TVOS:
1048 case PLATFORM_TVOSSIMULATOR:
1049 min_sdk_version = MIN_TVOS_TPRO_SDK_VERSION;
1050 break;
1051 case PLATFORM_WATCHOS:
1052 case PLATFORM_WATCHOSSIMULATOR:
1053 min_sdk_version = MIN_WATCHOS_TPRO_SDK_VERSION;
1054 break;
1055 case PLATFORM_DRIVERKIT:
1056 min_sdk_version = MIN_DRIVERKIT_TPRO_SDK_VERSION;
1057 break;
1058 default:
1059 /* TPRO is on by default for newer platforms */
1060 break;
1061 }
1062
1063 }
1064
1065 /*
1066 * If the passed in executable's vnode should use the RSR
1067 * shared region, then this should return TRUE, otherwise, return FALSE.
1068 */
1069 static uint32_t rsr_current_version = 0;
1070 boolean_t (*rsr_check_vnode)(void *vnode) = NULL;
1071
1072 boolean_t
vnode_is_rsr(vnode_t vp)1073 vnode_is_rsr(vnode_t vp)
1074 {
1075 if (!(vnode_isreg(vp) && vnode_tag(vp) == VT_APFS)) {
1076 return FALSE;
1077 }
1078
1079 if (rsr_check_vnode != NULL && rsr_check_vnode((void *)vp)) {
1080 return TRUE;
1081 }
1082 return FALSE;
1083 }
1084
1085
1086 uint32_t
rsr_get_version(void)1087 rsr_get_version(void)
1088 {
1089 return os_atomic_load(&rsr_current_version, relaxed);
1090 }
1091
1092 void
rsr_bump_version(void)1093 rsr_bump_version(void)
1094 {
1095 os_atomic_inc(&rsr_current_version, relaxed);
1096 }
1097
1098 #if XNU_TARGET_OS_OSX
1099 static int
1100 rsr_version_sysctl SYSCTL_HANDLER_ARGS
1101 {
1102 #pragma unused(arg1, arg2, oidp)
1103 int value = rsr_get_version();
1104 int error = SYSCTL_OUT(req, &value, sizeof(int));
1105 if (error) {
1106 return error;
1107 }
1108
1109 if (!req->newptr) {
1110 return 0;
1111 }
1112
1113 error = SYSCTL_IN(req, &value, sizeof(int));
1114 if (error) {
1115 return error;
1116 }
1117 if (value != 0) {
1118 rsr_bump_version();
1119 }
1120 return 0;
1121 }
1122
1123
1124 SYSCTL_PROC(_vm, OID_AUTO, shared_region_control,
1125 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_MASKED,
1126 0, 0, rsr_version_sysctl, "I", "");
1127 #endif /* XNU_TARGET_OS_OSX */
1128
1129 /*
1130 * exec_mach_imgact
1131 *
1132 * Image activator for mach-o 1.0 binaries.
1133 *
1134 * Parameters; struct image_params * image parameter block
1135 *
1136 * Returns: -1 not a fat binary (keep looking)
1137 * -2 Success: encapsulated binary: reread
1138 * >0 Failure: error number
1139 * EBADARCH Mach-o binary, but with an unrecognized
1140 * architecture
1141 * ENOMEM No memory for child process after -
1142 * can only happen after vfork()
1143 *
1144 * Important: This image activator is NOT byte order neutral.
1145 *
1146 * Note: A return value other than -1 indicates subsequent image
1147 * activators should not be given the opportunity to attempt
1148 * to activate the image.
1149 */
1150 static int
exec_mach_imgact(struct image_params * imgp)1151 exec_mach_imgact(struct image_params *imgp)
1152 {
1153 struct mach_header *mach_header = (struct mach_header *)imgp->ip_vdata;
1154 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
1155 int error = 0;
1156 task_t task;
1157 task_t new_task = NULL; /* protected by vfexec */
1158 thread_t thread;
1159 struct uthread *uthread;
1160 vm_map_t old_map = VM_MAP_NULL;
1161 vm_map_t map = VM_MAP_NULL;
1162 load_return_t lret;
1163 load_result_t load_result = {};
1164 struct _posix_spawnattr *psa = NULL;
1165 int spawn = (imgp->ip_flags & IMGPF_SPAWN);
1166 const int vfexec = 0;
1167 int exec = (imgp->ip_flags & IMGPF_EXEC);
1168 os_reason_t exec_failure_reason = OS_REASON_NULL;
1169 boolean_t reslide = FALSE;
1170 char * userspace_coredump_name = NULL;
1171
1172 /*
1173 * make sure it's a Mach-O 1.0 or Mach-O 2.0 binary; the difference
1174 * is a reserved field on the end, so for the most part, we can
1175 * treat them as if they were identical. Reverse-endian Mach-O
1176 * binaries are recognized but not compatible.
1177 */
1178 if ((mach_header->magic == MH_CIGAM) ||
1179 (mach_header->magic == MH_CIGAM_64)) {
1180 error = EBADARCH;
1181 goto bad;
1182 }
1183
1184 if ((mach_header->magic != MH_MAGIC) &&
1185 (mach_header->magic != MH_MAGIC_64)) {
1186 error = -1;
1187 goto bad;
1188 }
1189
1190 if (mach_header->filetype != MH_EXECUTE) {
1191 error = -1;
1192 goto bad;
1193 }
1194
1195 if (imgp->ip_origcputype != 0) {
1196 /* Fat header previously had an idea about this thin file */
1197 if (imgp->ip_origcputype != mach_header->cputype ||
1198 imgp->ip_origcpusubtype != mach_header->cpusubtype) {
1199 error = EBADARCH;
1200 goto bad;
1201 }
1202 } else {
1203 imgp->ip_origcputype = mach_header->cputype;
1204 imgp->ip_origcpusubtype = mach_header->cpusubtype;
1205 }
1206
1207 task = current_task();
1208 thread = current_thread();
1209 uthread = get_bsdthread_info(thread);
1210
1211 if ((mach_header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64) {
1212 imgp->ip_flags |= IMGPF_IS_64BIT_ADDR | IMGPF_IS_64BIT_DATA;
1213 }
1214
1215
1216 /* If posix_spawn binprefs exist, respect those prefs. */
1217 psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
1218 if (psa != NULL && psa->psa_binprefs[0] != 0) {
1219 int pr = 0;
1220 for (pr = 0; pr < NBINPREFS; pr++) {
1221 cpu_type_t pref = psa->psa_binprefs[pr];
1222 cpu_subtype_t subpref = psa->psa_subcpuprefs[pr];
1223
1224 if (pref == 0) {
1225 /* No suitable arch in the pref list */
1226 error = EBADARCH;
1227 goto bad;
1228 }
1229
1230 if (pref == CPU_TYPE_ANY) {
1231 /* Jump to regular grading */
1232 goto grade;
1233 }
1234
1235 if (binary_match(CPU_ARCH_MASK, pref, subpref,
1236 imgp->ip_origcputype, imgp->ip_origcpusubtype)) {
1237 goto grade;
1238 }
1239 }
1240 error = EBADARCH;
1241 goto bad;
1242 }
1243 grade:
1244 if (!grade_binary(imgp->ip_origcputype, imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK,
1245 imgp->ip_origcpusubtype & CPU_SUBTYPE_MASK, TRUE)) {
1246 error = EBADARCH;
1247 goto bad;
1248 }
1249
1250 if (validate_potential_simulator_binary(imgp->ip_origcputype, imgp,
1251 imgp->ip_arch_offset, imgp->ip_arch_size) != LOAD_SUCCESS) {
1252 #if __x86_64__
1253 const char *excpath;
1254 error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
1255 os_log_error(OS_LOG_DEFAULT, "Unsupported 32-bit executable: \"%s\"", (error) ? imgp->ip_vp->v_name : excpath);
1256 #endif
1257 error = EBADARCH;
1258 goto bad;
1259 }
1260
1261 #if defined(HAS_APPLE_PAC)
1262 assert(mach_header->cputype == CPU_TYPE_ARM64
1263 );
1264
1265 if ((mach_header->cputype == CPU_TYPE_ARM64 &&
1266 arm64_cpusubtype_uses_ptrauth(mach_header->cpusubtype))
1267 ) {
1268 imgp->ip_flags &= ~IMGPF_NOJOP;
1269 } else {
1270 imgp->ip_flags |= IMGPF_NOJOP;
1271 }
1272 #endif
1273
1274 /* Copy in arguments/environment from the old process */
1275 error = exec_extract_strings(imgp);
1276 if (error) {
1277 goto bad;
1278 }
1279
1280 AUDIT_ARG(argv, imgp->ip_startargv, imgp->ip_argc,
1281 imgp->ip_endargv - imgp->ip_startargv);
1282 AUDIT_ARG(envv, imgp->ip_endargv, imgp->ip_envc,
1283 imgp->ip_endenvv - imgp->ip_endargv);
1284
1285
1286
1287 /* reset local idea of thread, uthread, task */
1288 thread = imgp->ip_new_thread;
1289 uthread = get_bsdthread_info(thread);
1290 task = new_task = get_threadtask(thread);
1291
1292 /*
1293 * Load the Mach-O file.
1294 *
1295 * NOTE: An error after this point indicates we have potentially
1296 * destroyed or overwritten some process state while attempting an
1297 * execve() following a vfork(), which is an unrecoverable condition.
1298 * We send the new process an immediate SIGKILL to avoid it executing
1299 * any instructions in the mutated address space. For true spawns,
1300 * this is not the case, and "too late" is still not too late to
1301 * return an error code to the parent process.
1302 */
1303
1304 /*
1305 * Actually load the image file we previously decided to load.
1306 */
1307 lret = load_machfile(imgp, mach_header, thread, &map, &load_result);
1308 if (lret != LOAD_SUCCESS) {
1309 error = load_return_to_errno(lret);
1310
1311 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1312 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO, 0, 0);
1313 if (lret == LOAD_BADMACHO_UPX) {
1314 set_proc_name(imgp, p);
1315 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_UPX);
1316 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1317 } else {
1318 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1319
1320 if (bootarg_execfailurereports) {
1321 set_proc_name(imgp, p);
1322 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1323 }
1324 }
1325
1326 exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1327
1328 goto badtoolate;
1329 }
1330
1331 /*
1332 * ERROR RECOVERY
1333 *
1334 * load_machfile() returned the new VM map ("map") but we haven't
1335 * committed to it yet.
1336 * Any error path between here and the point where we commit to using
1337 * the new "map" (with swap_task_map()) should deallocate "map".
1338 */
1339
1340 #ifndef KASAN
1341 /*
1342 * Security: zone sanity checks on fresh boot or initproc re-exec.
1343 * launchd by design does not tear down its own service port on USR (rdar://72797967),
1344 * which means here is the earliest point we can assert on empty service port label zone,
1345 * after load_machfile() above terminates old launchd's IPC space.
1346 *
1347 * Disable on KASAN builds since zone_size_allocated() accounts for elements
1348 * under quarantine.
1349 */
1350 if (task_pid(task) == 1) {
1351 zone_userspace_reboot_checks();
1352 }
1353 #endif
1354
1355 proc_lock(p);
1356 p->p_cputype = imgp->ip_origcputype;
1357 p->p_cpusubtype = imgp->ip_origcpusubtype;
1358 proc_setplatformdata(p, load_result.ip_platform, load_result.lr_min_sdk, load_result.lr_sdk);
1359 exec_setup_tpro(imgp, &load_result);
1360
1361 vm_map_set_size_limit(map, proc_limitgetcur(p, RLIMIT_AS));
1362 vm_map_set_data_limit(map, proc_limitgetcur(p, RLIMIT_DATA));
1363 vm_map_set_user_wire_limit(map, (vm_size_t)proc_limitgetcur(p, RLIMIT_MEMLOCK));
1364 #if XNU_TARGET_OS_OSX
1365 if (proc_platform(p) == PLATFORM_IOS) {
1366 assert(vm_map_is_alien(map));
1367 } else {
1368 assert(!vm_map_is_alien(map));
1369 }
1370 #endif /* XNU_TARGET_OS_OSX */
1371 proc_unlock(p);
1372
1373 /*
1374 * Set code-signing flags if this binary is signed, or if parent has
1375 * requested them on exec.
1376 */
1377 if (load_result.csflags & CS_VALID) {
1378 imgp->ip_csflags |= load_result.csflags &
1379 (CS_VALID | CS_SIGNED | CS_DEV_CODE | CS_LINKER_SIGNED |
1380 CS_HARD | CS_KILL | CS_RESTRICT | CS_ENFORCEMENT | CS_REQUIRE_LV |
1381 CS_FORCED_LV | CS_ENTITLEMENTS_VALIDATED | CS_NO_UNTRUSTED_HELPERS | CS_RUNTIME |
1382 CS_ENTITLEMENT_FLAGS |
1383 CS_EXEC_SET_HARD | CS_EXEC_SET_KILL | CS_EXEC_SET_ENFORCEMENT);
1384 } else {
1385 imgp->ip_csflags &= ~CS_VALID;
1386 }
1387
1388 if (proc_getcsflags(p) & CS_EXEC_SET_HARD) {
1389 imgp->ip_csflags |= CS_HARD;
1390 }
1391 if (proc_getcsflags(p) & CS_EXEC_SET_KILL) {
1392 imgp->ip_csflags |= CS_KILL;
1393 }
1394 if (proc_getcsflags(p) & CS_EXEC_SET_ENFORCEMENT) {
1395 imgp->ip_csflags |= CS_ENFORCEMENT;
1396 }
1397 if (proc_getcsflags(p) & CS_EXEC_INHERIT_SIP) {
1398 if (proc_getcsflags(p) & CS_INSTALLER) {
1399 imgp->ip_csflags |= CS_INSTALLER;
1400 }
1401 if (proc_getcsflags(p) & CS_DATAVAULT_CONTROLLER) {
1402 imgp->ip_csflags |= CS_DATAVAULT_CONTROLLER;
1403 }
1404 if (proc_getcsflags(p) & CS_NVRAM_UNRESTRICTED) {
1405 imgp->ip_csflags |= CS_NVRAM_UNRESTRICTED;
1406 }
1407 }
1408
1409 #if __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX)
1410 /*
1411 * ptrauth version 0 is a preview ABI. Developers can opt into running
1412 * their own arm64e binaries for local testing, with the understanding
1413 * that future OSes may break ABI.
1414 */
1415 if ((imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
1416 CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(imgp->ip_origcpusubtype) == 0 &&
1417 !load_result.platform_binary &&
1418 !bootarg_arm64e_preview_abi) {
1419 static bool logged_once = false;
1420 set_proc_name(imgp, p);
1421
1422 printf("%s: not running binary \"%s\" built against preview arm64e ABI\n", __func__, p->p_name);
1423 if (!os_atomic_xchg(&logged_once, true, relaxed)) {
1424 printf("%s: (to allow this, add \"-arm64e_preview_abi\" to boot-args)\n", __func__);
1425 }
1426
1427 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1428 if (bootarg_execfailurereports) {
1429 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1430 exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1431 }
1432
1433 /* release new address space since we won't use it */
1434 vm_map_deallocate(map);
1435 map = VM_MAP_NULL;
1436 goto badtoolate;
1437 }
1438
1439 if ((imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) != CPU_SUBTYPE_ARM64E &&
1440 imgp->ip_origcputype == CPU_TYPE_ARM64 &&
1441 load_result.platform_binary &&
1442 (imgp->ip_flags & IMGPF_DRIVER) != 0) {
1443 set_proc_name(imgp, p);
1444 printf("%s: disallowing arm64 platform driverkit binary \"%s\", should be arm64e\n", __func__, p->p_name);
1445 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1446 if (bootarg_execfailurereports) {
1447 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1448 exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1449 }
1450
1451 /* release new address space since we won't use it */
1452 vm_map_deallocate(map);
1453 map = VM_MAP_NULL;
1454 goto badtoolate;
1455 }
1456 #endif /* __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX) */
1457
1458
1459 /*
1460 * Set up the shared cache region in the new process.
1461 *
1462 * Normally there is a single shared region per architecture.
1463 * However on systems with Pointer Authentication, we can create
1464 * multiple shared caches with the amount of sharing determined
1465 * by team-id or entitlement. Inherited shared region IDs are used
1466 * for system processes that need to match and be able to inspect
1467 * a pre-existing task.
1468 */
1469 int cpu_subtype = 0; /* all cpu_subtypes use the same shared region */
1470 #if __has_feature(ptrauth_calls)
1471 char *shared_region_id = NULL;
1472 size_t len;
1473 char *base;
1474 const char *cbase;
1475 #define TEAM_ID_PREFIX "T-"
1476 #define ENTITLE_PREFIX "E-"
1477 #define SR_PREFIX_LEN 2
1478 #define SR_ENTITLEMENT "com.apple.pac.shared_region_id"
1479
1480 if (cpu_type() == CPU_TYPE_ARM64 &&
1481 arm64_cpusubtype_uses_ptrauth(p->p_cpusubtype) &&
1482 (imgp->ip_flags & IMGPF_NOJOP) == 0) {
1483 assertf(p->p_cputype == CPU_TYPE_ARM64,
1484 "p %p cpu_type() 0x%x p->p_cputype 0x%x p->p_cpusubtype 0x%x",
1485 p, cpu_type(), p->p_cputype, p->p_cpusubtype);
1486
1487 /*
1488 * arm64e uses pointer authentication, so request a separate
1489 * shared region for this CPU subtype.
1490 */
1491 cpu_subtype = p->p_cpusubtype & ~CPU_SUBTYPE_MASK;
1492
1493 /*
1494 * Determine which shared cache to select based on being told,
1495 * matching a team-id or matching an entitlement.
1496 */
1497 if (imgp->ip_inherited_shared_region_id) {
1498 len = strlen(imgp->ip_inherited_shared_region_id);
1499 shared_region_id = kalloc_data(len + 1, Z_WAITOK | Z_NOFAIL);
1500 memcpy(shared_region_id, imgp->ip_inherited_shared_region_id, len + 1);
1501 } else if ((cbase = get_teamid_for_shared_region(imgp)) != NULL) {
1502 len = strlen(cbase);
1503 if (vm_shared_region_per_team_id) {
1504 shared_region_id = kalloc_data(len + SR_PREFIX_LEN + 1,
1505 Z_WAITOK | Z_NOFAIL);
1506 memcpy(shared_region_id, TEAM_ID_PREFIX, SR_PREFIX_LEN);
1507 memcpy(shared_region_id + SR_PREFIX_LEN, cbase, len + 1);
1508 }
1509 } else if ((base = IOVnodeGetEntitlement(imgp->ip_vp,
1510 (int64_t)imgp->ip_arch_offset, SR_ENTITLEMENT)) != NULL) {
1511 len = strlen(base);
1512 if (vm_shared_region_by_entitlement) {
1513 shared_region_id = kalloc_data(len + SR_PREFIX_LEN + 1,
1514 Z_WAITOK | Z_NOFAIL);
1515 memcpy(shared_region_id, ENTITLE_PREFIX, SR_PREFIX_LEN);
1516 memcpy(shared_region_id + SR_PREFIX_LEN, base, len + 1);
1517 }
1518 /* Discard the copy of the entitlement */
1519 kfree_data(base, len + 1);
1520 }
1521 }
1522
1523 if (imgp->ip_flags & IMGPF_RESLIDE) {
1524 reslide = TRUE;
1525 }
1526
1527 /* use "" as the default shared_region_id */
1528 if (shared_region_id == NULL) {
1529 shared_region_id = kalloc_data(1, Z_WAITOK | Z_ZERO | Z_NOFAIL);
1530 }
1531
1532 /* ensure there's a unique pointer signing key for this shared_region_id */
1533 shared_region_key_alloc(shared_region_id,
1534 imgp->ip_inherited_shared_region_id != NULL, imgp->ip_inherited_jop_pid);
1535 task_set_shared_region_id(task, shared_region_id);
1536 shared_region_id = NULL;
1537 #endif /* __has_feature(ptrauth_calls) */
1538
1539 #if CONFIG_ROSETTA
1540 if (imgp->ip_flags & IMGPF_ROSETTA) {
1541 OSBitOrAtomic(P_TRANSLATED, &p->p_flag);
1542 } else if (p->p_flag & P_TRANSLATED) {
1543 OSBitAndAtomic(~P_TRANSLATED, &p->p_flag);
1544 }
1545 #endif
1546
1547 int cputype = cpu_type();
1548
1549 uint32_t rsr_version = 0;
1550 #if XNU_TARGET_OS_OSX
1551 if (vnode_is_rsr(imgp->ip_vp)) {
1552 rsr_version = rsr_get_version();
1553 os_atomic_or(&p->p_ladvflag, P_RSR, relaxed);
1554 os_atomic_or(&p->p_vfs_iopolicy, P_VFS_IOPOLICY_ALTLINK, relaxed);
1555 }
1556 #endif /* XNU_TARGET_OS_OSX */
1557
1558 vm_map_exec(map, task, load_result.is_64bit_addr,
1559 (void *)p->p_fd.fd_rdir, cputype, cpu_subtype, reslide,
1560 (imgp->ip_flags & IMGPF_DRIVER) != 0,
1561 rsr_version);
1562
1563 /*
1564 * Close file descriptors which specify close-on-exec.
1565 */
1566 fdt_exec(p, psa != NULL ? psa->psa_flags : 0, imgp->ip_new_thread, exec);
1567
1568 /*
1569 * deal with set[ug]id.
1570 */
1571 error = exec_handle_sugid(imgp);
1572 if (error) {
1573 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1574 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE, 0, 0);
1575
1576 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE);
1577 if (bootarg_execfailurereports) {
1578 set_proc_name(imgp, p);
1579 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1580 }
1581
1582 /* release new address space since we won't use it */
1583 vm_map_deallocate(map);
1584 map = VM_MAP_NULL;
1585 goto badtoolate;
1586 }
1587
1588 /*
1589 * Commit to new map.
1590 *
1591 * Swap the new map for the old for target task, which consumes
1592 * our new map reference but each leaves us responsible for the
1593 * old_map reference. That lets us get off the pmap associated
1594 * with it, and then we can release it.
1595 *
1596 * The map needs to be set on the target task which is different
1597 * than current task, thus swap_task_map is used instead of
1598 * vm_map_switch.
1599 */
1600 old_map = swap_task_map(task, thread, map);
1601 #if MACH_ASSERT
1602 /*
1603 * Reset the pmap's process info to prevent ledger checks
1604 * which might fail due to the ledgers being shared between
1605 * the old and new pmaps.
1606 */
1607 vm_map_pmap_set_process(old_map, -1, "<old_map>");
1608 #endif /* MACH_ASSERT */
1609 vm_map_deallocate(old_map);
1610 old_map = NULL;
1611
1612 lret = activate_exec_state(task, p, thread, &load_result);
1613 if (lret != KERN_SUCCESS) {
1614 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1615 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE, 0, 0);
1616
1617 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE);
1618 if (bootarg_execfailurereports) {
1619 set_proc_name(imgp, p);
1620 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1621 }
1622
1623 goto badtoolate;
1624 }
1625
1626 /*
1627 * deal with voucher on exec-calling thread.
1628 */
1629 if (imgp->ip_new_thread == NULL) {
1630 thread_set_mach_voucher(current_thread(), IPC_VOUCHER_NULL);
1631 }
1632
1633 /* Make sure we won't interrupt ourself signalling a partial process */
1634 if (!vfexec && !spawn && (p->p_lflag & P_LTRACED)) {
1635 psignal(p, SIGTRAP);
1636 }
1637
1638 if (load_result.unixproc &&
1639 create_unix_stack(get_task_map(task),
1640 &load_result,
1641 p) != KERN_SUCCESS) {
1642 error = load_return_to_errno(LOAD_NOSPACE);
1643
1644 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1645 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC, 0, 0);
1646
1647 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC);
1648 if (bootarg_execfailurereports) {
1649 set_proc_name(imgp, p);
1650 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1651 }
1652
1653 goto badtoolate;
1654 }
1655
1656 /*
1657 * The load result will have already been munged by AMFI to include the
1658 * platform binary flag if boot-args dictated it (AMFI will mark anything
1659 * that doesn't go through the upcall path as a platform binary if its
1660 * enforcement is disabled).
1661 */
1662 if (load_result.platform_binary) {
1663 if (cs_debug) {
1664 printf("setting platform binary on task: pid = %d\n", proc_getpid(p));
1665 }
1666
1667 /*
1668 * We must use 'task' here because the proc's task has not yet been
1669 * switched to the new one.
1670 */
1671 task_set_platform_binary(task, TRUE);
1672 } else {
1673 if (cs_debug) {
1674 printf("clearing platform binary on task: pid = %d\n", proc_getpid(p));
1675 }
1676
1677 task_set_platform_binary(task, FALSE);
1678 }
1679
1680 /*
1681 * Set starting EXC_GUARD and control port behavior for task now that
1682 * platform is set. Use the name directly from imgp since we haven't
1683 * set_proc_name() yet. Also make control port for the task and main thread
1684 * immovable/pinned based on task's option.
1685 *
1686 * Must happen before main thread port copyout in exc_add_apple_strings.
1687 */
1688 task_set_exc_guard_ctrl_port_default(task, thread,
1689 imgp->ip_ndp->ni_cnd.cn_nameptr,
1690 (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen,
1691 proc_is_simulated(p),
1692 load_result.ip_platform,
1693 load_result.lr_sdk);
1694
1695 error = exec_add_apple_strings(imgp, &load_result); /* copies out main thread port */
1696
1697 if (error) {
1698 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1699 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT, 0, 0);
1700
1701 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT);
1702 if (bootarg_execfailurereports) {
1703 set_proc_name(imgp, p);
1704 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1705 }
1706 goto badtoolate;
1707 }
1708
1709 /* Switch to target task's map to copy out strings */
1710 old_map = vm_map_switch(get_task_map(task));
1711
1712 if (load_result.unixproc) {
1713 user_addr_t ap;
1714
1715 /*
1716 * Copy the strings area out into the new process address
1717 * space.
1718 */
1719 ap = p->user_stack;
1720 error = exec_copyout_strings(imgp, &ap);
1721 if (error) {
1722 vm_map_switch(old_map);
1723
1724 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1725 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS, 0, 0);
1726
1727 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS);
1728 if (bootarg_execfailurereports) {
1729 set_proc_name(imgp, p);
1730 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1731 }
1732 goto badtoolate;
1733 }
1734 /* Set the stack */
1735 thread_setuserstack(thread, ap);
1736 }
1737
1738 if (load_result.dynlinker || load_result.is_rosetta) {
1739 user_addr_t ap;
1740 int new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
1741
1742 /* Adjust the stack */
1743 ap = thread_adjuserstack(thread, -new_ptr_size);
1744 error = copyoutptr(load_result.mach_header, ap, new_ptr_size);
1745
1746 if (error) {
1747 vm_map_switch(old_map);
1748
1749 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1750 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER, 0, 0);
1751
1752 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER);
1753 if (bootarg_execfailurereports) {
1754 set_proc_name(imgp, p);
1755 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1756 }
1757 goto badtoolate;
1758 }
1759 error = task_set_dyld_info(task, load_result.all_image_info_addr,
1760 load_result.all_image_info_size);
1761 if (error) {
1762 vm_map_switch(old_map);
1763
1764 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1765 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO, 0, 0);
1766
1767 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO);
1768 if (bootarg_execfailurereports) {
1769 set_proc_name(imgp, p);
1770 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1771 }
1772 error = EINVAL;
1773 goto badtoolate;
1774 }
1775 }
1776
1777 #if CONFIG_ROSETTA
1778 if (load_result.is_rosetta) {
1779 // Add an fd for the executable file for Rosetta's use
1780 int main_binary_fd;
1781 struct fileproc *fp;
1782
1783 error = falloc(p, &fp, &main_binary_fd, imgp->ip_vfs_context);
1784 if (error) {
1785 vm_map_switch(old_map);
1786
1787 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1788 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC, 0, 0);
1789
1790 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC);
1791 if (bootarg_execfailurereports) {
1792 set_proc_name(imgp, p);
1793 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1794 }
1795 goto badtoolate;
1796 }
1797
1798 error = VNOP_OPEN(imgp->ip_vp, FREAD, imgp->ip_vfs_context);
1799 if (error) {
1800 vm_map_switch(old_map);
1801
1802 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1803 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC, 0, 0);
1804
1805 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC);
1806 if (bootarg_execfailurereports) {
1807 set_proc_name(imgp, p);
1808 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1809 }
1810 goto cleanup_rosetta_fp;
1811 }
1812
1813 fp->fp_glob->fg_flag = FREAD;
1814 fp->fp_glob->fg_ops = &vnops;
1815 fp_set_data(fp, imgp->ip_vp);
1816
1817 proc_fdlock(p);
1818 procfdtbl_releasefd(p, main_binary_fd, NULL);
1819 fp_drop(p, main_binary_fd, fp, 1);
1820 proc_fdunlock(p);
1821
1822 vnode_ref(imgp->ip_vp);
1823
1824 // Pass the dyld load address, main binary fd, and dyld fd on the stack
1825 uint64_t ap = thread_adjuserstack(thread, -24);
1826
1827 error = copyoutptr((user_addr_t)load_result.dynlinker_fd, ap, 8);
1828 if (error) {
1829 vm_map_switch(old_map);
1830
1831 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1832 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
1833
1834 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
1835 if (bootarg_execfailurereports) {
1836 set_proc_name(imgp, p);
1837 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1838 }
1839 goto cleanup_rosetta_fp;
1840 }
1841
1842 error = copyoutptr(load_result.dynlinker_mach_header, ap + 8, 8);
1843 if (error) {
1844 vm_map_switch(old_map);
1845
1846 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1847 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
1848
1849 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
1850 if (bootarg_execfailurereports) {
1851 set_proc_name(imgp, p);
1852 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1853 }
1854 goto cleanup_rosetta_fp;
1855 }
1856
1857 error = copyoutptr((user_addr_t)main_binary_fd, ap + 16, 8);
1858 if (error) {
1859 vm_map_switch(old_map);
1860
1861 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1862 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
1863
1864 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
1865 if (bootarg_execfailurereports) {
1866 set_proc_name(imgp, p);
1867 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1868 }
1869 goto cleanup_rosetta_fp;
1870 }
1871
1872 cleanup_rosetta_fp:
1873 if (error) {
1874 fp_free(p, load_result.dynlinker_fd, load_result.dynlinker_fp);
1875 fp_free(p, main_binary_fd, fp);
1876 goto badtoolate;
1877 }
1878 }
1879
1880 #endif
1881
1882 /* Avoid immediate VM faults back into kernel */
1883 exec_prefault_data(p, imgp, &load_result);
1884
1885 vm_map_switch(old_map);
1886
1887 /*
1888 * Reset signal state.
1889 */
1890 execsigs(p, thread);
1891
1892 /*
1893 * need to cancel async IO requests that can be cancelled and wait for those
1894 * already active. MAY BLOCK!
1895 */
1896 _aio_exec( p );
1897
1898 #if SYSV_SHM
1899 /* FIXME: Till vmspace inherit is fixed: */
1900 if (!vfexec && p->vm_shm) {
1901 shmexec(p);
1902 }
1903 #endif
1904 #if SYSV_SEM
1905 /* Clean up the semaphores */
1906 semexit(p);
1907 #endif
1908
1909 /*
1910 * Remember file name for accounting.
1911 */
1912 p->p_acflag &= ~AFORK;
1913
1914 set_proc_name(imgp, p);
1915
1916 #if CONFIG_SECLUDED_MEMORY
1917 if (secluded_for_apps &&
1918 load_result.platform_binary) {
1919 if (strncmp(p->p_name,
1920 "Camera",
1921 sizeof(p->p_name)) == 0) {
1922 task_set_could_use_secluded_mem(task, TRUE);
1923 } else {
1924 task_set_could_use_secluded_mem(task, FALSE);
1925 }
1926 if (strncmp(p->p_name,
1927 "mediaserverd",
1928 sizeof(p->p_name)) == 0) {
1929 task_set_could_also_use_secluded_mem(task, TRUE);
1930 }
1931 }
1932 #endif /* CONFIG_SECLUDED_MEMORY */
1933
1934 #if __arm64__
1935 if (load_result.legacy_footprint) {
1936 task_set_legacy_footprint(task);
1937 }
1938 #endif /* __arm64__ */
1939
1940 pal_dbg_set_task_name(task);
1941
1942 #if DEVELOPMENT || DEBUG
1943 /*
1944 * Update the pid an proc name for importance base if any
1945 */
1946 task_importance_update_owner_info(task);
1947 #endif
1948
1949 proc_setexecutableuuid(p, &load_result.uuid[0]);
1950
1951 #if CONFIG_DTRACE
1952 dtrace_proc_exec(p);
1953 #endif
1954
1955 if (kdebug_enable) {
1956 long args[4] = {};
1957
1958 uintptr_t fsid = 0, fileid = 0;
1959 if (imgp->ip_vattr) {
1960 uint64_t fsid64 = vnode_get_va_fsid(imgp->ip_vattr);
1961 fsid = (uintptr_t)fsid64;
1962 fileid = (uintptr_t)imgp->ip_vattr->va_fileid;
1963 // check for (unexpected) overflow and trace zero in that case
1964 if (fsid != fsid64 || fileid != imgp->ip_vattr->va_fileid) {
1965 fsid = fileid = 0;
1966 }
1967 }
1968 KERNEL_DEBUG_CONSTANT_IST1(TRACE_DATA_EXEC, proc_getpid(p), fsid, fileid, 0,
1969 (uintptr_t)thread_tid(thread));
1970
1971 extern void kdebug_proc_name_args(struct proc *proc, long args[static 4]);
1972 kdebug_proc_name_args(p, args);
1973 KERNEL_DEBUG_CONSTANT_IST1(TRACE_STRING_EXEC, args[0], args[1],
1974 args[2], args[3], (uintptr_t)thread_tid(thread));
1975 }
1976
1977
1978 /*
1979 * If posix_spawned with the START_SUSPENDED flag, stop the
1980 * process before it runs.
1981 */
1982 if (imgp->ip_px_sa != NULL) {
1983 psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
1984 if (psa->psa_flags & POSIX_SPAWN_START_SUSPENDED) {
1985 proc_lock(p);
1986 p->p_stat = SSTOP;
1987 proc_unlock(p);
1988 (void) task_suspend_internal(task);
1989 }
1990 }
1991
1992 /*
1993 * mark as execed
1994 */
1995 OSBitOrAtomic(P_EXEC, &p->p_flag);
1996 proc_resetregister(p);
1997 if (p->p_pptr && (p->p_lflag & P_LPPWAIT)) {
1998 proc_lock(p);
1999 p->p_lflag &= ~P_LPPWAIT;
2000 proc_unlock(p);
2001 wakeup((caddr_t)p->p_pptr);
2002 }
2003
2004 /*
2005 * Set up dext coredumps on kernel panic.
2006 * This requires the following:
2007 * - dext_panic_coredump=1 boot-arg (enabled by default on DEVELOPMENT, DEBUG and certain Seed builds)
2008 * - process must be a driver
2009 * - process must have the com.apple.private.enable-coredump-on-panic entitlement, and the
2010 * entitlement has a string value.
2011 * - process must have the com.apple.private.enable-coredump-on-panic-seed-privacy-approved
2012 * entitlement (Seed builds only).
2013 *
2014 * The core dump file name is formatted with the entitlement string value, followed by a hyphen
2015 * and the process PID.
2016 */
2017 if (enable_dext_coredumps_on_panic &&
2018 (imgp->ip_flags & IMGPF_DRIVER) != 0 &&
2019 (userspace_coredump_name = IOVnodeGetEntitlement(imgp->ip_vp,
2020 (int64_t)imgp->ip_arch_offset, USERSPACE_COREDUMP_PANIC_ENTITLEMENT)) != NULL) {
2021 size_t userspace_coredump_name_len = strlen(userspace_coredump_name);
2022
2023 char core_name[MACH_CORE_FILEHEADER_NAMELEN];
2024 /* 16 - NULL char - strlen("-") - maximum of 5 digits for pid */
2025 snprintf(core_name, MACH_CORE_FILEHEADER_NAMELEN, "%.9s-%d", userspace_coredump_name, proc_getpid(p));
2026
2027 kern_register_userspace_coredump(task, core_name);
2028
2029 /* Discard the copy of the entitlement */
2030 kfree_data(userspace_coredump_name, userspace_coredump_name_len + 1);
2031 userspace_coredump_name = NULL;
2032 }
2033
2034 goto done;
2035
2036 badtoolate:
2037 /* Don't allow child process to execute any instructions */
2038 if (!spawn) {
2039 {
2040 assert(exec_failure_reason != OS_REASON_NULL);
2041 if (bootarg_execfailurereports) {
2042 set_proc_name(imgp, current_proc());
2043 }
2044 psignal_with_reason(current_proc(), SIGKILL, exec_failure_reason);
2045 exec_failure_reason = OS_REASON_NULL;
2046
2047 if (exec) {
2048 /* Terminate the exec copy task */
2049 task_terminate_internal(task);
2050 }
2051 }
2052
2053 /* We can't stop this system call at this point, so just pretend we succeeded */
2054 error = 0;
2055 } else {
2056 os_reason_free(exec_failure_reason);
2057 exec_failure_reason = OS_REASON_NULL;
2058 }
2059
2060 done:
2061 if (load_result.threadstate) {
2062 kfree_data(load_result.threadstate, load_result.threadstate_sz);
2063 load_result.threadstate = NULL;
2064 }
2065
2066 bad:
2067 /* If we hit this, we likely would have leaked an exit reason */
2068 assert(exec_failure_reason == OS_REASON_NULL);
2069 return error;
2070 }
2071
2072
2073
2074
2075 /*
2076 * Our image activator table; this is the table of the image types we are
2077 * capable of loading. We list them in order of preference to ensure the
2078 * fastest image load speed.
2079 *
2080 * XXX hardcoded, for now; should use linker sets
2081 */
2082 struct execsw {
2083 int(*const ex_imgact)(struct image_params *);
2084 const char *ex_name;
2085 }const execsw[] = {
2086 { exec_mach_imgact, "Mach-o Binary" },
2087 { exec_fat_imgact, "Fat Binary" },
2088 { exec_shell_imgact, "Interpreter Script" },
2089 { NULL, NULL}
2090 };
2091
2092
2093 /*
2094 * exec_activate_image
2095 *
2096 * Description: Iterate through the available image activators, and activate
2097 * the image associated with the imgp structure. We start with
2098 * the activator for Mach-o binaries followed by that for Fat binaries
2099 * for Interpreter scripts.
2100 *
2101 * Parameters: struct image_params * Image parameter block
2102 *
2103 * Returns: 0 Success
2104 * ENOEXEC No activator for image.
2105 * EBADEXEC The executable is corrupt/unknown
2106 * execargs_alloc:EINVAL Invalid argument
2107 * execargs_alloc:EACCES Permission denied
2108 * execargs_alloc:EINTR Interrupted function
2109 * execargs_alloc:ENOMEM Not enough space
2110 * exec_save_path:EFAULT Bad address
2111 * exec_save_path:ENAMETOOLONG Filename too long
2112 * exec_check_permissions:EACCES Permission denied
2113 * exec_check_permissions:ENOEXEC Executable file format error
2114 * exec_check_permissions:ETXTBSY Text file busy [misuse of error code]
2115 * exec_check_permissions:???
2116 * namei:???
2117 * vn_rdwr:??? [anything vn_rdwr can return]
2118 * <ex_imgact>:??? [anything an imgact can return]
2119 * EDEADLK Process is being terminated
2120 */
2121 static int
exec_activate_image(struct image_params * imgp)2122 exec_activate_image(struct image_params *imgp)
2123 {
2124 struct nameidata *ndp = NULL;
2125 const char *excpath;
2126 int error;
2127 int resid;
2128 int once = 1; /* save SGUID-ness for interpreted files */
2129 int i;
2130 int itercount = 0;
2131 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2132
2133 /*
2134 * For exec, the translock needs to be taken on old proc and not
2135 * on new shadow proc.
2136 */
2137 if (imgp->ip_flags & IMGPF_EXEC) {
2138 p = current_proc();
2139 }
2140
2141 error = execargs_alloc(imgp);
2142 if (error) {
2143 goto bad_notrans;
2144 }
2145
2146 error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
2147 if (error) {
2148 goto bad_notrans;
2149 }
2150
2151 /* Use excpath, which contains the copyin-ed exec path */
2152 DTRACE_PROC1(exec, uintptr_t, excpath);
2153
2154 ndp = kalloc_type(struct nameidata, Z_WAITOK | Z_ZERO | Z_NOFAIL);
2155
2156 NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
2157 UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
2158
2159 again:
2160 error = namei(ndp);
2161 if (error) {
2162 if (error == ERESTART) {
2163 error = EINTR;
2164 }
2165 goto bad_notrans;
2166 }
2167 imgp->ip_ndp = ndp; /* successful namei(); call nameidone() later */
2168 imgp->ip_vp = ndp->ni_vp; /* if set, need to vnode_put() at some point */
2169
2170 /*
2171 * Before we start the transition from binary A to binary B, make
2172 * sure another thread hasn't started exiting the process. We grab
2173 * the proc lock to check p_lflag initially, and the transition
2174 * mechanism ensures that the value doesn't change after we release
2175 * the lock.
2176 */
2177 proc_lock(p);
2178 if (p->p_lflag & P_LEXIT) {
2179 error = EDEADLK;
2180 proc_unlock(p);
2181 goto bad_notrans;
2182 }
2183 error = proc_transstart(p, 1, 0);
2184 proc_unlock(p);
2185 if (error) {
2186 goto bad_notrans;
2187 }
2188
2189 error = exec_check_permissions(imgp);
2190 if (error) {
2191 goto bad;
2192 }
2193
2194 /* Copy; avoid invocation of an interpreter overwriting the original */
2195 if (once) {
2196 once = 0;
2197 *imgp->ip_origvattr = *imgp->ip_vattr;
2198 }
2199
2200 error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata, PAGE_SIZE, 0,
2201 UIO_SYSSPACE, IO_NODELOCKED,
2202 vfs_context_ucred(imgp->ip_vfs_context),
2203 &resid, vfs_context_proc(imgp->ip_vfs_context));
2204 if (error) {
2205 goto bad;
2206 }
2207
2208 if (resid) {
2209 memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
2210 }
2211
2212 encapsulated_binary:
2213 /* Limit the number of iterations we will attempt on each binary */
2214 if (++itercount > EAI_ITERLIMIT) {
2215 error = EBADEXEC;
2216 goto bad;
2217 }
2218 error = -1;
2219 for (i = 0; error == -1 && execsw[i].ex_imgact != NULL; i++) {
2220 error = (*execsw[i].ex_imgact)(imgp);
2221
2222 switch (error) {
2223 /* case -1: not claimed: continue */
2224 case -2: /* Encapsulated binary, imgp->ip_XXX set for next iteration */
2225 goto encapsulated_binary;
2226
2227 case -3: /* Interpreter */
2228 #if CONFIG_MACF
2229 /*
2230 * Copy the script label for later use. Note that
2231 * the label can be different when the script is
2232 * actually read by the interpreter.
2233 */
2234 if (imgp->ip_scriptlabelp) {
2235 mac_vnode_label_free(imgp->ip_scriptlabelp);
2236 imgp->ip_scriptlabelp = NULL;
2237 }
2238 imgp->ip_scriptlabelp = mac_vnode_label_alloc(NULL);
2239 if (imgp->ip_scriptlabelp == NULL) {
2240 error = ENOMEM;
2241 break;
2242 }
2243 mac_vnode_label_copy(mac_vnode_label(imgp->ip_vp),
2244 imgp->ip_scriptlabelp);
2245
2246 /*
2247 * Take a ref of the script vnode for later use.
2248 */
2249 if (imgp->ip_scriptvp) {
2250 vnode_put(imgp->ip_scriptvp);
2251 imgp->ip_scriptvp = NULLVP;
2252 }
2253 if (vnode_getwithref(imgp->ip_vp) == 0) {
2254 imgp->ip_scriptvp = imgp->ip_vp;
2255 }
2256 #endif
2257
2258 nameidone(ndp);
2259
2260 vnode_put(imgp->ip_vp);
2261 imgp->ip_vp = NULL; /* already put */
2262 imgp->ip_ndp = NULL; /* already nameidone */
2263
2264 /* Use excpath, which exec_shell_imgact reset to the interpreter */
2265 NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF,
2266 UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
2267
2268 proc_transend(p, 0);
2269 goto again;
2270
2271 default:
2272 break;
2273 }
2274 }
2275
2276 if (error == -1) {
2277 error = ENOEXEC;
2278 } else if (error == 0) {
2279 if (imgp->ip_flags & IMGPF_INTERPRET && ndp->ni_vp) {
2280 AUDIT_ARG(vnpath, ndp->ni_vp, ARG_VNODE2);
2281 }
2282
2283 /*
2284 * Call out to allow 3rd party notification of exec.
2285 * Ignore result of kauth_authorize_fileop call.
2286 */
2287 if (kauth_authorize_fileop_has_listeners()) {
2288 kauth_authorize_fileop(vfs_context_ucred(imgp->ip_vfs_context),
2289 KAUTH_FILEOP_EXEC,
2290 (uintptr_t)ndp->ni_vp, 0);
2291 }
2292 }
2293 bad:
2294 proc_transend(p, 0);
2295
2296 bad_notrans:
2297 if (imgp->ip_strings) {
2298 execargs_free(imgp);
2299 }
2300 if (imgp->ip_ndp) {
2301 nameidone(imgp->ip_ndp);
2302 }
2303 kfree_type(struct nameidata, ndp);
2304
2305 return error;
2306 }
2307
2308 /*
2309 * exec_validate_spawnattr_policy
2310 *
2311 * Description: Validates the entitlements required to set the apptype.
2312 *
2313 * Parameters: int psa_apptype posix spawn attribute apptype
2314 *
2315 * Returns: 0 Success
2316 * EPERM Failure
2317 */
2318 static errno_t
exec_validate_spawnattr_policy(int psa_apptype)2319 exec_validate_spawnattr_policy(int psa_apptype)
2320 {
2321 if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
2322 int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
2323 if (proctype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
2324 if (!IOCurrentTaskHasEntitlement(POSIX_SPAWN_ENTITLEMENT_DRIVER)) {
2325 return EPERM;
2326 }
2327 }
2328 }
2329
2330 return 0;
2331 }
2332
2333 /*
2334 * exec_handle_spawnattr_policy
2335 *
2336 * Description: Decode and apply the posix_spawn apptype, qos clamp, and watchport ports to the task.
2337 *
2338 * Parameters: proc_t p process to apply attributes to
2339 * int psa_apptype posix spawn attribute apptype
2340 *
2341 * Returns: 0 Success
2342 */
2343 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)2344 exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
2345 task_role_t psa_darwin_role, struct exec_port_actions *port_actions)
2346 {
2347 int apptype = TASK_APPTYPE_NONE;
2348 int qos_clamp = THREAD_QOS_UNSPECIFIED;
2349 task_role_t role = TASK_UNSPECIFIED;
2350
2351 if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
2352 int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
2353
2354 switch (proctype) {
2355 case POSIX_SPAWN_PROC_TYPE_DAEMON_INTERACTIVE:
2356 apptype = TASK_APPTYPE_DAEMON_INTERACTIVE;
2357 break;
2358 case POSIX_SPAWN_PROC_TYPE_DAEMON_STANDARD:
2359 apptype = TASK_APPTYPE_DAEMON_STANDARD;
2360 break;
2361 case POSIX_SPAWN_PROC_TYPE_DAEMON_ADAPTIVE:
2362 apptype = TASK_APPTYPE_DAEMON_ADAPTIVE;
2363 break;
2364 case POSIX_SPAWN_PROC_TYPE_DAEMON_BACKGROUND:
2365 apptype = TASK_APPTYPE_DAEMON_BACKGROUND;
2366 break;
2367 case POSIX_SPAWN_PROC_TYPE_APP_DEFAULT:
2368 apptype = TASK_APPTYPE_APP_DEFAULT;
2369 break;
2370 case POSIX_SPAWN_PROC_TYPE_DRIVER:
2371 apptype = TASK_APPTYPE_DRIVER;
2372 break;
2373 default:
2374 apptype = TASK_APPTYPE_NONE;
2375 /* TODO: Should an invalid value here fail the spawn? */
2376 break;
2377 }
2378 }
2379
2380 if (psa_qos_clamp != POSIX_SPAWN_PROC_CLAMP_NONE) {
2381 switch (psa_qos_clamp) {
2382 case POSIX_SPAWN_PROC_CLAMP_UTILITY:
2383 qos_clamp = THREAD_QOS_UTILITY;
2384 break;
2385 case POSIX_SPAWN_PROC_CLAMP_BACKGROUND:
2386 qos_clamp = THREAD_QOS_BACKGROUND;
2387 break;
2388 case POSIX_SPAWN_PROC_CLAMP_MAINTENANCE:
2389 qos_clamp = THREAD_QOS_MAINTENANCE;
2390 break;
2391 default:
2392 qos_clamp = THREAD_QOS_UNSPECIFIED;
2393 /* TODO: Should an invalid value here fail the spawn? */
2394 break;
2395 }
2396 }
2397
2398 if (psa_darwin_role != PRIO_DARWIN_ROLE_DEFAULT) {
2399 proc_darwin_role_to_task_role(psa_darwin_role, &role);
2400 }
2401
2402 if (apptype != TASK_APPTYPE_NONE ||
2403 qos_clamp != THREAD_QOS_UNSPECIFIED ||
2404 role != TASK_UNSPECIFIED ||
2405 port_actions->portwatch_count) {
2406 proc_set_task_spawnpolicy(proc_task(p), thread, apptype, qos_clamp, role,
2407 port_actions->portwatch_array, port_actions->portwatch_count);
2408 }
2409
2410 if (port_actions->registered_count) {
2411 if (mach_ports_register(proc_task(p), port_actions->registered_array,
2412 port_actions->registered_count)) {
2413 return EINVAL;
2414 }
2415 /* mach_ports_register() consumed the array */
2416 port_actions->registered_array = NULL;
2417 port_actions->registered_count = 0;
2418 }
2419
2420 return 0;
2421 }
2422
2423 static void
exec_port_actions_destroy(struct exec_port_actions * port_actions)2424 exec_port_actions_destroy(struct exec_port_actions *port_actions)
2425 {
2426 if (port_actions->portwatch_array) {
2427 for (uint32_t i = 0; i < port_actions->portwatch_count; i++) {
2428 ipc_port_t port = NULL;
2429 if ((port = port_actions->portwatch_array[i]) != NULL) {
2430 ipc_port_release_send(port);
2431 }
2432 }
2433 kfree_type(ipc_port_t, port_actions->portwatch_count,
2434 port_actions->portwatch_array);
2435 }
2436
2437 if (port_actions->registered_array) {
2438 for (uint32_t i = 0; i < port_actions->registered_count; i++) {
2439 ipc_port_t port = NULL;
2440 if ((port = port_actions->registered_array[i]) != NULL) {
2441 ipc_port_release_send(port);
2442 }
2443 }
2444 kfree_type(ipc_port_t, port_actions->registered_count,
2445 port_actions->registered_array);
2446 }
2447 }
2448
2449 /*
2450 * exec_handle_port_actions
2451 *
2452 * Description: Go through the _posix_port_actions_t contents,
2453 * calling task_set_special_port, task_set_exception_ports
2454 * and/or audit_session_spawnjoin for the current task.
2455 *
2456 * Parameters: struct image_params * Image parameter block
2457 *
2458 * Returns: 0 Success
2459 * EINVAL Failure
2460 * ENOTSUP Illegal posix_spawn attr flag was set
2461 */
2462 static errno_t
exec_handle_port_actions(struct image_params * imgp,struct exec_port_actions * actions)2463 exec_handle_port_actions(struct image_params *imgp,
2464 struct exec_port_actions *actions)
2465 {
2466 _posix_spawn_port_actions_t pacts = imgp->ip_px_spa;
2467 #if CONFIG_AUDIT
2468 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2469 #endif
2470 _ps_port_action_t *act = NULL;
2471 task_t task = get_threadtask(imgp->ip_new_thread);
2472 ipc_port_t port = NULL;
2473 errno_t ret = 0;
2474 int i, portwatch_i = 0, registered_i = 0;
2475 kern_return_t kr;
2476 boolean_t task_has_watchport_boost = task_has_watchports(current_task());
2477 boolean_t in_exec = (imgp->ip_flags & IMGPF_EXEC);
2478 int ptrauth_task_port_count = 0;
2479
2480 for (i = 0; i < pacts->pspa_count; i++) {
2481 act = &pacts->pspa_actions[i];
2482
2483 switch (act->port_type) {
2484 case PSPA_SPECIAL:
2485 case PSPA_EXCEPTION:
2486 #if CONFIG_AUDIT
2487 case PSPA_AU_SESSION:
2488 #endif
2489 break;
2490 case PSPA_IMP_WATCHPORTS:
2491 if (++actions->portwatch_count > TASK_MAX_WATCHPORT_COUNT) {
2492 ret = EINVAL;
2493 goto done;
2494 }
2495 break;
2496 case PSPA_REGISTERED_PORTS:
2497 if (++actions->registered_count > TASK_PORT_REGISTER_MAX) {
2498 ret = EINVAL;
2499 goto done;
2500 }
2501 break;
2502 case PSPA_PTRAUTH_TASK_PORT:
2503 if (++ptrauth_task_port_count > 1) {
2504 ret = EINVAL;
2505 goto done;
2506 }
2507 break;
2508 default:
2509 ret = EINVAL;
2510 goto done;
2511 }
2512 }
2513
2514 if (actions->portwatch_count) {
2515 if (in_exec && task_has_watchport_boost) {
2516 ret = EINVAL;
2517 goto done;
2518 }
2519 actions->portwatch_array = kalloc_type(ipc_port_t,
2520 actions->portwatch_count, Z_WAITOK | Z_ZERO);
2521 if (actions->portwatch_array == NULL) {
2522 ret = ENOMEM;
2523 goto done;
2524 }
2525 }
2526
2527 if (actions->registered_count) {
2528 actions->registered_array = kalloc_type(ipc_port_t,
2529 actions->registered_count, Z_WAITOK | Z_ZERO);
2530 if (actions->registered_array == NULL) {
2531 ret = ENOMEM;
2532 goto done;
2533 }
2534 }
2535
2536 for (i = 0; i < pacts->pspa_count; i++) {
2537 act = &pacts->pspa_actions[i];
2538
2539 if (MACH_PORT_VALID(act->new_port)) {
2540 kr = ipc_object_copyin(get_task_ipcspace(current_task()),
2541 act->new_port, MACH_MSG_TYPE_COPY_SEND,
2542 (ipc_object_t *) &port, 0, NULL, IPC_OBJECT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND);
2543
2544 if (kr != KERN_SUCCESS) {
2545 ret = EINVAL;
2546 goto done;
2547 }
2548 } else {
2549 /* it's NULL or DEAD */
2550 port = CAST_MACH_NAME_TO_PORT(act->new_port);
2551 }
2552
2553 switch (act->port_type) {
2554 case PSPA_SPECIAL:
2555 kr = task_set_special_port(task, act->which, port);
2556
2557 if (kr != KERN_SUCCESS) {
2558 ret = EINVAL;
2559 }
2560 break;
2561
2562 case PSPA_EXCEPTION:
2563 kr = task_set_exception_ports(task, act->mask, port,
2564 act->behavior, act->flavor);
2565 if (kr != KERN_SUCCESS) {
2566 ret = EINVAL;
2567 }
2568 break;
2569 #if CONFIG_AUDIT
2570 case PSPA_AU_SESSION:
2571 ret = audit_session_spawnjoin(p, task, port);
2572 if (ret) {
2573 /* audit_session_spawnjoin() has already dropped the reference in case of error. */
2574 goto done;
2575 }
2576
2577 break;
2578 #endif
2579 case PSPA_IMP_WATCHPORTS:
2580 if (actions->portwatch_array) {
2581 /* hold on to this till end of spawn */
2582 actions->portwatch_array[portwatch_i++] = port;
2583 } else {
2584 ipc_port_release_send(port);
2585 }
2586 break;
2587 case PSPA_REGISTERED_PORTS:
2588 /* hold on to this till end of spawn */
2589 actions->registered_array[registered_i++] = port;
2590 break;
2591
2592 case PSPA_PTRAUTH_TASK_PORT:
2593 #if defined(HAS_APPLE_PAC)
2594 {
2595 task_t ptr_auth_task = convert_port_to_task(port);
2596
2597 if (ptr_auth_task == TASK_NULL) {
2598 ret = EINVAL;
2599 break;
2600 }
2601
2602 imgp->ip_inherited_shared_region_id =
2603 task_get_vm_shared_region_id_and_jop_pid(ptr_auth_task,
2604 &imgp->ip_inherited_jop_pid);
2605
2606 /* Deallocate task ref returned by convert_port_to_task */
2607 task_deallocate(ptr_auth_task);
2608 }
2609 #endif /* HAS_APPLE_PAC */
2610
2611 /* consume the port right in case of success */
2612 ipc_port_release_send(port);
2613 break;
2614 default:
2615 ret = EINVAL;
2616 break;
2617 }
2618
2619 if (ret) {
2620 /* action failed, so release port resources */
2621 ipc_port_release_send(port);
2622 break;
2623 }
2624 }
2625
2626 done:
2627 if (0 != ret) {
2628 DTRACE_PROC1(spawn__port__failure, mach_port_name_t, act->new_port);
2629 }
2630 return ret;
2631 }
2632
2633 /*
2634 * exec_handle_file_actions
2635 *
2636 * Description: Go through the _posix_file_actions_t contents applying the
2637 * open, close, and dup2 operations to the open file table for
2638 * the current process.
2639 *
2640 * Parameters: struct image_params * Image parameter block
2641 *
2642 * Returns: 0 Success
2643 * ???
2644 *
2645 * Note: Actions are applied in the order specified, with the credential
2646 * of the parent process. This is done to permit the parent
2647 * process to utilize POSIX_SPAWN_RESETIDS to drop privilege in
2648 * the child following operations the child may in fact not be
2649 * normally permitted to perform.
2650 */
2651 static int
exec_handle_file_actions(struct image_params * imgp,short psa_flags)2652 exec_handle_file_actions(struct image_params *imgp, short psa_flags)
2653 {
2654 int error = 0;
2655 int action;
2656 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2657 _posix_spawn_file_actions_t px_sfap = imgp->ip_px_sfa;
2658 int ival[2]; /* dummy retval for system calls) */
2659 #if CONFIG_AUDIT
2660 struct uthread *uthread = current_uthread();
2661 #endif
2662
2663 for (action = 0; action < px_sfap->psfa_act_count; action++) {
2664 _psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
2665
2666 switch (psfa->psfaa_type) {
2667 case PSFA_OPEN: {
2668 /*
2669 * Open is different, in that it requires the use of
2670 * a path argument, which is normally copied in from
2671 * user space; because of this, we have to support an
2672 * open from kernel space that passes an address space
2673 * context of UIO_SYSSPACE, and casts the address
2674 * argument to a user_addr_t.
2675 */
2676 struct vnode_attr *vap;
2677 struct nameidata *ndp;
2678 int mode = psfa->psfaa_openargs.psfao_mode;
2679 int origfd;
2680 struct {
2681 struct vnode_attr va;
2682 struct nameidata nd;
2683 } *__open_data;
2684
2685 __open_data = kalloc_type(typeof(*__open_data), Z_WAITOK | Z_ZERO);
2686 if (__open_data == NULL) {
2687 error = ENOMEM;
2688 break;
2689 }
2690
2691 vap = &__open_data->va;
2692 ndp = &__open_data->nd;
2693
2694 VATTR_INIT(vap);
2695 /* Mask off all but regular access permissions */
2696 mode = ((mode & ~p->p_fd.fd_cmask) & ALLPERMS) & ~S_ISTXT;
2697 VATTR_SET(vap, va_mode, mode & ACCESSPERMS);
2698
2699 AUDIT_SUBCALL_ENTER(OPEN, p, uthread);
2700
2701 NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
2702 CAST_USER_ADDR_T(psfa->psfaa_openargs.psfao_path),
2703 imgp->ip_vfs_context);
2704
2705 error = open1(imgp->ip_vfs_context, ndp,
2706 psfa->psfaa_openargs.psfao_oflag,
2707 vap, NULL, NULL, &origfd, AUTH_OPEN_NOAUTHFD);
2708
2709 kfree_type(typeof(*__open_data), __open_data);
2710
2711 AUDIT_SUBCALL_EXIT(uthread, error);
2712
2713 /*
2714 * If there's an error, or we get the right fd by
2715 * accident, then drop out here. This is easier than
2716 * reworking all the open code to preallocate fd
2717 * slots, and internally taking one as an argument.
2718 */
2719 if (error || origfd == psfa->psfaa_filedes) {
2720 break;
2721 }
2722
2723 /*
2724 * If we didn't fall out from an error, we ended up
2725 * with the wrong fd; so now we've got to try to dup2
2726 * it to the right one.
2727 */
2728 AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
2729 error = dup2(p, origfd, psfa->psfaa_filedes, ival);
2730 AUDIT_SUBCALL_EXIT(uthread, error);
2731 if (error) {
2732 break;
2733 }
2734
2735 /*
2736 * Finally, close the original fd.
2737 */
2738 AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
2739 error = close_nocancel(p, origfd);
2740 AUDIT_SUBCALL_EXIT(uthread, error);
2741 }
2742 break;
2743
2744 case PSFA_DUP2: {
2745 AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
2746 error = dup2(p, psfa->psfaa_filedes,
2747 psfa->psfaa_dup2args.psfad_newfiledes, ival);
2748 AUDIT_SUBCALL_EXIT(uthread, error);
2749 }
2750 break;
2751
2752 case PSFA_FILEPORT_DUP2: {
2753 ipc_port_t port;
2754 kern_return_t kr;
2755 int origfd;
2756
2757 if (!MACH_PORT_VALID(psfa->psfaa_fileport)) {
2758 error = EINVAL;
2759 break;
2760 }
2761
2762 kr = ipc_object_copyin(get_task_ipcspace(current_task()),
2763 psfa->psfaa_fileport, MACH_MSG_TYPE_COPY_SEND,
2764 (ipc_object_t *) &port, 0, NULL, IPC_OBJECT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND);
2765
2766 if (kr != KERN_SUCCESS) {
2767 error = EINVAL;
2768 break;
2769 }
2770
2771 error = fileport_makefd(p, port, 0, &origfd);
2772
2773 if (IPC_PORT_NULL != port) {
2774 ipc_port_release_send(port);
2775 }
2776
2777 if (error || origfd == psfa->psfaa_dup2args.psfad_newfiledes) {
2778 break;
2779 }
2780
2781 AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
2782 error = dup2(p, origfd,
2783 psfa->psfaa_dup2args.psfad_newfiledes, ival);
2784 AUDIT_SUBCALL_EXIT(uthread, error);
2785 if (error) {
2786 break;
2787 }
2788
2789 AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
2790 error = close_nocancel(p, origfd);
2791 AUDIT_SUBCALL_EXIT(uthread, error);
2792 }
2793 break;
2794
2795 case PSFA_CLOSE: {
2796 AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
2797 error = close_nocancel(p, psfa->psfaa_filedes);
2798 AUDIT_SUBCALL_EXIT(uthread, error);
2799 }
2800 break;
2801
2802 case PSFA_INHERIT: {
2803 struct fileproc *fp;
2804
2805 /*
2806 * Check to see if the descriptor exists, and
2807 * ensure it's -not- marked as close-on-exec.
2808 *
2809 * Attempting to "inherit" a guarded fd will
2810 * result in a error.
2811 */
2812
2813 proc_fdlock(p);
2814 if ((fp = fp_get_noref_locked(p, psfa->psfaa_filedes)) == NULL) {
2815 error = EBADF;
2816 } else if (fp->fp_guard_attrs) {
2817 error = fp_guard_exception(p, psfa->psfaa_filedes,
2818 fp, kGUARD_EXC_NOCLOEXEC);
2819 } else {
2820 fp->fp_flags &= ~FP_CLOEXEC;
2821 error = 0;
2822 }
2823 proc_fdunlock(p);
2824 }
2825 break;
2826
2827 case PSFA_CHDIR: {
2828 /*
2829 * Chdir is different, in that it requires the use of
2830 * a path argument, which is normally copied in from
2831 * user space; because of this, we have to support a
2832 * chdir from kernel space that passes an address space
2833 * context of UIO_SYSSPACE, and casts the address
2834 * argument to a user_addr_t.
2835 */
2836 struct nameidata *nd;
2837 nd = kalloc_type(struct nameidata,
2838 Z_WAITOK | Z_ZERO | Z_NOFAIL);
2839
2840 AUDIT_SUBCALL_ENTER(CHDIR, p, uthread);
2841 NDINIT(nd, LOOKUP, OP_CHDIR, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
2842 CAST_USER_ADDR_T(psfa->psfaa_chdirargs.psfac_path),
2843 imgp->ip_vfs_context);
2844
2845 error = chdir_internal(p, imgp->ip_vfs_context, nd, 0);
2846 kfree_type(struct nameidata, nd);
2847 AUDIT_SUBCALL_EXIT(uthread, error);
2848 }
2849 break;
2850
2851 case PSFA_FCHDIR: {
2852 struct fchdir_args fchdira;
2853
2854 fchdira.fd = psfa->psfaa_filedes;
2855
2856 AUDIT_SUBCALL_ENTER(FCHDIR, p, uthread);
2857 error = fchdir(p, &fchdira, ival);
2858 AUDIT_SUBCALL_EXIT(uthread, error);
2859 }
2860 break;
2861
2862 default:
2863 error = EINVAL;
2864 break;
2865 }
2866
2867 /* All file actions failures are considered fatal, per POSIX */
2868
2869 if (error) {
2870 if (PSFA_OPEN == psfa->psfaa_type) {
2871 DTRACE_PROC1(spawn__open__failure, uintptr_t,
2872 psfa->psfaa_openargs.psfao_path);
2873 } else {
2874 DTRACE_PROC1(spawn__fd__failure, int, psfa->psfaa_filedes);
2875 }
2876 break;
2877 }
2878 }
2879
2880 if (error != 0 || (psa_flags & POSIX_SPAWN_CLOEXEC_DEFAULT) == 0) {
2881 return error;
2882 }
2883
2884 /*
2885 * If POSIX_SPAWN_CLOEXEC_DEFAULT is set, behave (during
2886 * this spawn only) as if "close on exec" is the default
2887 * disposition of all pre-existing file descriptors. In this case,
2888 * the list of file descriptors mentioned in the file actions
2889 * are the only ones that can be inherited, so mark them now.
2890 *
2891 * The actual closing part comes later, in fdt_exec().
2892 */
2893 proc_fdlock(p);
2894 for (action = 0; action < px_sfap->psfa_act_count; action++) {
2895 _psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
2896 int fd = psfa->psfaa_filedes;
2897
2898 switch (psfa->psfaa_type) {
2899 case PSFA_DUP2:
2900 case PSFA_FILEPORT_DUP2:
2901 fd = psfa->psfaa_dup2args.psfad_newfiledes;
2902 OS_FALLTHROUGH;
2903 case PSFA_OPEN:
2904 case PSFA_INHERIT:
2905 *fdflags(p, fd) |= UF_INHERIT;
2906 break;
2907
2908 case PSFA_CLOSE:
2909 case PSFA_CHDIR:
2910 case PSFA_FCHDIR:
2911 /*
2912 * Although PSFA_FCHDIR does have a file descriptor, it is not
2913 * *creating* one, thus we do not automatically mark it for
2914 * inheritance under POSIX_SPAWN_CLOEXEC_DEFAULT. A client that
2915 * wishes it to be inherited should use the PSFA_INHERIT action
2916 * explicitly.
2917 */
2918 break;
2919 }
2920 }
2921 proc_fdunlock(p);
2922
2923 return 0;
2924 }
2925
2926 #if CONFIG_MACF
2927 /*
2928 * Check that the extension's data is within the bounds of the
2929 * allocation storing all extensions' data
2930 */
2931 static inline errno_t
exec_spawnattr_validate_policyext_data(const struct ip_px_smpx_s * px_s,const _ps_mac_policy_extension_t * ext)2932 exec_spawnattr_validate_policyext_data(const struct ip_px_smpx_s *px_s,
2933 const _ps_mac_policy_extension_t *ext)
2934 {
2935 uint64_t dataend;
2936
2937 if (__improbable(os_add_overflow(ext->dataoff, ext->datalen, &dataend))) {
2938 return EOVERFLOW;
2939 }
2940 if (__improbable(dataend > px_s->datalen)) {
2941 return EINVAL;
2942 }
2943
2944 return 0;
2945 }
2946
2947 /*
2948 * exec_spawnattr_getmacpolicyinfo
2949 */
2950 void *
exec_spawnattr_getmacpolicyinfo(const void * macextensions,const char * policyname,size_t * lenp)2951 exec_spawnattr_getmacpolicyinfo(const void *macextensions, const char *policyname, size_t *lenp)
2952 {
2953 const struct ip_px_smpx_s *px_s = macextensions;
2954 const struct _posix_spawn_mac_policy_extensions *psmx = NULL;
2955 int i;
2956
2957 if (px_s == NULL) {
2958 return NULL;
2959 }
2960
2961 psmx = px_s->array;
2962 if (psmx == NULL) {
2963 return NULL;
2964 }
2965
2966 for (i = 0; i < psmx->psmx_count; i++) {
2967 const _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
2968 if (strncmp(extension->policyname, policyname, sizeof(extension->policyname)) == 0) {
2969 if (__improbable(exec_spawnattr_validate_policyext_data(px_s, extension))) {
2970 panic("invalid mac policy extension data");
2971 }
2972 if (lenp != NULL) {
2973 *lenp = (size_t)extension->datalen;
2974 }
2975 return (void *)((uintptr_t)px_s->data + extension->dataoff);
2976 }
2977 }
2978
2979 if (lenp != NULL) {
2980 *lenp = 0;
2981 }
2982 return NULL;
2983 }
2984
2985 static int
spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc * px_args,struct ip_px_smpx_s * pxsp)2986 spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc *px_args,
2987 struct ip_px_smpx_s *pxsp)
2988 {
2989 _posix_spawn_mac_policy_extensions_t psmx = NULL;
2990 uint8_t *data = NULL;
2991 uint64_t datalen = 0;
2992 uint64_t dataoff = 0;
2993 int error = 0;
2994
2995 bzero(pxsp, sizeof(*pxsp));
2996
2997 if (px_args->mac_extensions_size < PS_MAC_EXTENSIONS_SIZE(1) ||
2998 px_args->mac_extensions_size > PAGE_SIZE) {
2999 error = EINVAL;
3000 goto bad;
3001 }
3002
3003 psmx = kalloc_data(px_args->mac_extensions_size, Z_WAITOK);
3004 if (psmx == NULL) {
3005 error = ENOMEM;
3006 goto bad;
3007 }
3008
3009 error = copyin(px_args->mac_extensions, psmx, px_args->mac_extensions_size);
3010 if (error) {
3011 goto bad;
3012 }
3013
3014 size_t extsize = PS_MAC_EXTENSIONS_SIZE(psmx->psmx_count);
3015 if (extsize == 0 || extsize > px_args->mac_extensions_size) {
3016 error = EINVAL;
3017 goto bad;
3018 }
3019
3020 for (int i = 0; i < psmx->psmx_count; i++) {
3021 _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
3022 if (extension->datalen == 0 || extension->datalen > PAGE_SIZE) {
3023 error = EINVAL;
3024 goto bad;
3025 }
3026 if (__improbable(os_add_overflow(datalen, extension->datalen, &datalen))) {
3027 error = ENOMEM;
3028 goto bad;
3029 }
3030 }
3031
3032 data = kalloc_data((vm_size_t)datalen, Z_WAITOK);
3033 if (data == NULL) {
3034 error = ENOMEM;
3035 goto bad;
3036 }
3037
3038 for (int i = 0; i < psmx->psmx_count; i++) {
3039 _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
3040
3041 #if !__LP64__
3042 if (extension->data > UINT32_MAX) {
3043 goto bad;
3044 }
3045 #endif
3046 error = copyin((user_addr_t)extension->data, &data[dataoff], (size_t)extension->datalen);
3047 if (error) {
3048 error = ENOMEM;
3049 goto bad;
3050 }
3051 extension->dataoff = dataoff;
3052 dataoff += extension->datalen;
3053 }
3054
3055 pxsp->array = psmx;
3056 pxsp->data = data;
3057 pxsp->datalen = datalen;
3058 return 0;
3059
3060 bad:
3061 kfree_data(psmx, px_args->mac_extensions_size);
3062 kfree_data(data, (vm_size_t)datalen);
3063 return error;
3064 }
3065 #endif /* CONFIG_MACF */
3066
3067 #if CONFIG_COALITIONS
3068 static inline void
spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES])3069 spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES])
3070 {
3071 for (int c = 0; c < COALITION_NUM_TYPES; c++) {
3072 if (coal[c]) {
3073 coalition_remove_active(coal[c]);
3074 coalition_release(coal[c]);
3075 }
3076 }
3077 }
3078 #endif
3079
3080 #if CONFIG_PERSONAS
3081 static int
spawn_validate_persona(struct _posix_spawn_persona_info * px_persona)3082 spawn_validate_persona(struct _posix_spawn_persona_info *px_persona)
3083 {
3084 int error = 0;
3085 struct persona *persona = NULL;
3086
3087 if (!IOCurrentTaskHasEntitlement( PERSONA_MGMT_ENTITLEMENT)) {
3088 return EPERM;
3089 }
3090
3091 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
3092 if (px_persona->pspi_ngroups > NGROUPS_MAX) {
3093 return EINVAL;
3094 }
3095 }
3096
3097 persona = persona_lookup(px_persona->pspi_id);
3098 if (!persona) {
3099 error = ESRCH;
3100 goto out;
3101 }
3102
3103 out:
3104 if (persona) {
3105 persona_put(persona);
3106 }
3107
3108 return error;
3109 }
3110
3111 static int
spawn_persona_adopt(proc_t p,struct _posix_spawn_persona_info * px_persona)3112 spawn_persona_adopt(proc_t p, struct _posix_spawn_persona_info *px_persona)
3113 {
3114 int ret;
3115 kauth_cred_t cred;
3116 struct persona *persona = NULL;
3117
3118 /*
3119 * we want to spawn into the given persona, but we want to override
3120 * the kauth with a different UID/GID combo
3121 */
3122 persona = persona_lookup(px_persona->pspi_id);
3123 if (!persona) {
3124 return ESRCH;
3125 }
3126
3127 cred = kauth_cred_proc_ref(p);
3128
3129 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_UID) {
3130 cred = kauth_cred_setresuid(cred,
3131 px_persona->pspi_uid,
3132 px_persona->pspi_uid,
3133 px_persona->pspi_uid,
3134 KAUTH_UID_NONE);
3135 }
3136
3137 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GID) {
3138 cred = kauth_cred_setresgid(cred,
3139 px_persona->pspi_gid,
3140 px_persona->pspi_gid,
3141 px_persona->pspi_gid);
3142 }
3143
3144 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
3145 cred = kauth_cred_setgroups(cred,
3146 px_persona->pspi_groups,
3147 px_persona->pspi_ngroups,
3148 px_persona->pspi_gmuid);
3149 }
3150
3151 ret = persona_proc_adopt(p, persona, cred);
3152
3153 kauth_cred_unref(&cred);
3154 persona_put(persona);
3155 return ret;
3156 }
3157 #endif
3158
3159 #if __arm64__
3160 #if DEVELOPMENT || DEBUG
3161 TUNABLE(int, legacy_footprint_entitlement_mode, "legacy_footprint_entitlement_mode",
3162 LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE);
3163
3164 __startup_func
3165 static void
legacy_footprint_entitlement_mode_init(void)3166 legacy_footprint_entitlement_mode_init(void)
3167 {
3168 /*
3169 * legacy_footprint_entitlement_mode specifies the behavior we want associated
3170 * with the entitlement. The supported modes are:
3171 *
3172 * LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE:
3173 * Indicates that we want every process to have the memory accounting
3174 * that is available in iOS 12.0 and beyond.
3175 *
3176 * LEGACY_FOOTPRINT_ENTITLEMENT_IOS11_ACCT:
3177 * Indicates that for every process that has the 'legacy footprint entitlement',
3178 * we want to give it the old iOS 11.0 accounting behavior which accounted some
3179 * of the process's memory to the kernel.
3180 *
3181 * LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE:
3182 * Indicates that for every process that has the 'legacy footprint entitlement',
3183 * we want it to have a higher memory limit which will help them acclimate to the
3184 * iOS 12.0 (& beyond) accounting behavior that does the right accounting.
3185 * The bonus added to the system-wide task limit to calculate this higher memory limit
3186 * is available in legacy_footprint_bonus_mb.
3187 */
3188
3189 if (legacy_footprint_entitlement_mode < LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE ||
3190 legacy_footprint_entitlement_mode > LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE) {
3191 legacy_footprint_entitlement_mode = LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE;
3192 }
3193 }
3194 STARTUP(TUNABLES, STARTUP_RANK_MIDDLE, legacy_footprint_entitlement_mode_init);
3195 #else
3196 const int legacy_footprint_entitlement_mode = LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE;
3197 #endif
3198
3199 static inline void
proc_legacy_footprint_entitled(proc_t p,task_t task)3200 proc_legacy_footprint_entitled(proc_t p, task_t task)
3201 {
3202 #pragma unused(p)
3203 boolean_t legacy_footprint_entitled;
3204
3205 switch (legacy_footprint_entitlement_mode) {
3206 case LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE:
3207 /* the entitlement is ignored */
3208 break;
3209 case LEGACY_FOOTPRINT_ENTITLEMENT_IOS11_ACCT:
3210 /* the entitlement grants iOS11 legacy accounting */
3211 legacy_footprint_entitled = memorystatus_task_has_legacy_footprint_entitlement(proc_task(p));
3212 if (legacy_footprint_entitled) {
3213 task_set_legacy_footprint(task);
3214 }
3215 break;
3216 case LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE:
3217 /* the entitlement grants a footprint limit increase */
3218 legacy_footprint_entitled = memorystatus_task_has_legacy_footprint_entitlement(proc_task(p));
3219 if (legacy_footprint_entitled) {
3220 task_set_extra_footprint_limit(task);
3221 }
3222 break;
3223 default:
3224 break;
3225 }
3226 }
3227
3228 static inline void
proc_ios13extended_footprint_entitled(proc_t p,task_t task)3229 proc_ios13extended_footprint_entitled(proc_t p, task_t task)
3230 {
3231 #pragma unused(p)
3232 boolean_t ios13extended_footprint_entitled;
3233
3234 /* the entitlement grants a footprint limit increase */
3235 ios13extended_footprint_entitled = memorystatus_task_has_ios13extended_footprint_limit(proc_task(p));
3236 if (ios13extended_footprint_entitled) {
3237 task_set_ios13extended_footprint_limit(task);
3238 }
3239 }
3240
3241 static inline void
proc_increased_memory_limit_entitled(proc_t p,task_t task)3242 proc_increased_memory_limit_entitled(proc_t p, task_t task)
3243 {
3244 bool entitled = memorystatus_task_has_increased_memory_limit_entitlement(task);
3245
3246 if (entitled) {
3247 memorystatus_act_on_entitled_task_limit(p);
3248 }
3249 }
3250
3251 /*
3252 * Check for any of the various entitlements that permit a higher
3253 * task footprint limit or alternate accounting and apply them.
3254 */
3255 static inline void
proc_footprint_entitlement_hacks(proc_t p,task_t task)3256 proc_footprint_entitlement_hacks(proc_t p, task_t task)
3257 {
3258 proc_legacy_footprint_entitled(p, task);
3259 proc_ios13extended_footprint_entitled(p, task);
3260 proc_increased_memory_limit_entitled(p, task);
3261 }
3262 #endif /* __arm64__ */
3263
3264 #if CONFIG_MACF
3265 /*
3266 * Processes with certain entitlements are granted a jumbo-size VM map.
3267 */
3268 static inline void
proc_apply_jit_and_jumbo_va_policies(proc_t p,task_t task)3269 proc_apply_jit_and_jumbo_va_policies(proc_t p, task_t task)
3270 {
3271 bool jit_entitled;
3272 jit_entitled = (mac_proc_check_map_anon(p, 0, 0, 0, MAP_JIT, NULL) == 0);
3273 if (jit_entitled || (IOTaskHasEntitlement(task,
3274 "com.apple.developer.kernel.extended-virtual-addressing")) ||
3275 memorystatus_task_has_increased_memory_limit_entitlement(task)) {
3276 vm_map_set_jumbo(get_task_map(task));
3277 if (jit_entitled) {
3278 vm_map_set_jit_entitled(get_task_map(task));
3279
3280 }
3281 }
3282 }
3283 #endif /* CONFIG_MACF */
3284
3285 static inline void
proc_apply_tpro(struct image_params * imgp,task_t task)3286 proc_apply_tpro(struct image_params *imgp, task_t task)
3287 {
3288 #if defined(__arm64e__)
3289 if (imgp->ip_flags & IMGPF_HW_TPRO) {
3290 vm_map_set_tpro(get_task_map(task));
3291 }
3292 #else /* __arm64e__ */
3293 (void)imgp;
3294 (void)task;
3295 #endif /* __arm64e__ */
3296 }
3297
3298 #if CONFIG_MAP_RANGES
3299 /*
3300 * First party processes are opted in to the use of VM heap ranges.
3301 */
3302 static inline void
proc_apply_vm_range_policies(proc_t p __unused,task_t t)3303 proc_apply_vm_range_policies(proc_t p __unused, task_t t)
3304 {
3305 if (task_get_platform_binary(t)) {
3306 vm_map_range_configure(get_task_map(t));
3307 }
3308 }
3309 #endif /* CONFIG_MAP_RANGES */
3310
3311 static int
spawn_posix_cred_adopt(proc_t p,struct _posix_spawn_posix_cred_info * px_pcred_info)3312 spawn_posix_cred_adopt(proc_t p,
3313 struct _posix_spawn_posix_cred_info *px_pcred_info)
3314 {
3315 int error = 0;
3316
3317 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GID) {
3318 struct setgid_args args = {
3319 .gid = px_pcred_info->pspci_gid,
3320 };
3321 error = setgid(p, &args, NULL);
3322 if (error) {
3323 return error;
3324 }
3325 }
3326
3327 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
3328 error = setgroups_internal(p,
3329 px_pcred_info->pspci_ngroups,
3330 px_pcred_info->pspci_groups,
3331 px_pcred_info->pspci_gmuid);
3332 if (error) {
3333 return error;
3334 }
3335 }
3336
3337 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_UID) {
3338 struct setuid_args args = {
3339 .uid = px_pcred_info->pspci_uid,
3340 };
3341 error = setuid(p, &args, NULL);
3342 if (error) {
3343 return error;
3344 }
3345 }
3346 return 0;
3347 }
3348
3349 /*
3350 * posix_spawn
3351 *
3352 * Parameters: uap->pid Pointer to pid return area
3353 * uap->fname File name to exec
3354 * uap->argp Argument list
3355 * uap->envp Environment list
3356 *
3357 * Returns: 0 Success
3358 * EINVAL Invalid argument
3359 * ENOTSUP Not supported
3360 * ENOEXEC Executable file format error
3361 * exec_activate_image:EINVAL Invalid argument
3362 * exec_activate_image:EACCES Permission denied
3363 * exec_activate_image:EINTR Interrupted function
3364 * exec_activate_image:ENOMEM Not enough space
3365 * exec_activate_image:EFAULT Bad address
3366 * exec_activate_image:ENAMETOOLONG Filename too long
3367 * exec_activate_image:ENOEXEC Executable file format error
3368 * exec_activate_image:ETXTBSY Text file busy [misuse of error code]
3369 * exec_activate_image:EAUTH Image decryption failed
3370 * exec_activate_image:EBADEXEC The executable is corrupt/unknown
3371 * exec_activate_image:???
3372 * mac_execve_enter:???
3373 *
3374 * TODO: Expect to need __mac_posix_spawn() at some point...
3375 * Handle posix_spawnattr_t
3376 * Handle posix_spawn_file_actions_t
3377 */
3378 int
posix_spawn(proc_t ap,struct posix_spawn_args * uap,int32_t * retval)3379 posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval)
3380 {
3381 proc_t p = ap;
3382 user_addr_t pid = uap->pid;
3383 int ival[2]; /* dummy retval for setpgid() */
3384 char *subsystem_root_path = NULL;
3385 struct image_params *imgp = NULL;
3386 struct vnode_attr *vap = NULL;
3387 struct vnode_attr *origvap = NULL;
3388 struct uthread *uthread = 0; /* compiler complains if not set to 0*/
3389 int error, sig;
3390 int is_64 = IS_64BIT_PROCESS(p);
3391 struct vfs_context context;
3392 struct user__posix_spawn_args_desc px_args = {};
3393 struct _posix_spawnattr px_sa = {};
3394 _posix_spawn_file_actions_t px_sfap = NULL;
3395 _posix_spawn_port_actions_t px_spap = NULL;
3396 struct __kern_sigaction vec;
3397 boolean_t spawn_no_exec = FALSE;
3398 boolean_t proc_transit_set = TRUE;
3399 boolean_t proc_signal_set = TRUE;
3400 boolean_t exec_done = FALSE;
3401 struct exec_port_actions port_actions = { };
3402 vm_size_t px_sa_offset = offsetof(struct _posix_spawnattr, psa_ports);
3403 task_t old_task = current_task();
3404 task_t new_task = NULL;
3405 boolean_t should_release_proc_ref = FALSE;
3406 void *inherit = NULL;
3407 uint8_t crash_behavior = 0;
3408 uint64_t crash_behavior_deadline = 0;
3409 #if CONFIG_PERSONAS
3410 struct _posix_spawn_persona_info *px_persona = NULL;
3411 #endif
3412 struct _posix_spawn_posix_cred_info *px_pcred_info = NULL;
3413 struct {
3414 struct image_params imgp;
3415 struct vnode_attr va;
3416 struct vnode_attr origva;
3417 } *__spawn_data;
3418
3419 /*
3420 * Allocate a big chunk for locals instead of using stack since these
3421 * structures are pretty big.
3422 */
3423 __spawn_data = kalloc_type(typeof(*__spawn_data), Z_WAITOK | Z_ZERO);
3424 if (__spawn_data == NULL) {
3425 error = ENOMEM;
3426 goto bad;
3427 }
3428 imgp = &__spawn_data->imgp;
3429 vap = &__spawn_data->va;
3430 origvap = &__spawn_data->origva;
3431
3432 /* Initialize the common data in the image_params structure */
3433 imgp->ip_user_fname = uap->path;
3434 imgp->ip_user_argv = uap->argv;
3435 imgp->ip_user_envv = uap->envp;
3436 imgp->ip_vattr = vap;
3437 imgp->ip_origvattr = origvap;
3438 imgp->ip_vfs_context = &context;
3439 imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE);
3440 imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
3441 imgp->ip_mac_return = 0;
3442 imgp->ip_px_persona = NULL;
3443 imgp->ip_px_pcred_info = NULL;
3444 imgp->ip_cs_error = OS_REASON_NULL;
3445 imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
3446 imgp->ip_subsystem_root_path = NULL;
3447 imgp->ip_inherited_shared_region_id = NULL;
3448 imgp->ip_inherited_jop_pid = 0;
3449 uthread_set_exec_data(current_uthread(), imgp);
3450
3451 if (uap->adesc != USER_ADDR_NULL) {
3452 if (is_64) {
3453 error = copyin(uap->adesc, &px_args, sizeof(px_args));
3454 } else {
3455 struct user32__posix_spawn_args_desc px_args32;
3456
3457 error = copyin(uap->adesc, &px_args32, sizeof(px_args32));
3458
3459 /*
3460 * Convert arguments descriptor from external 32 bit
3461 * representation to internal 64 bit representation
3462 */
3463 px_args.attr_size = px_args32.attr_size;
3464 px_args.attrp = CAST_USER_ADDR_T(px_args32.attrp);
3465 px_args.file_actions_size = px_args32.file_actions_size;
3466 px_args.file_actions = CAST_USER_ADDR_T(px_args32.file_actions);
3467 px_args.port_actions_size = px_args32.port_actions_size;
3468 px_args.port_actions = CAST_USER_ADDR_T(px_args32.port_actions);
3469 px_args.mac_extensions_size = px_args32.mac_extensions_size;
3470 px_args.mac_extensions = CAST_USER_ADDR_T(px_args32.mac_extensions);
3471 px_args.coal_info_size = px_args32.coal_info_size;
3472 px_args.coal_info = CAST_USER_ADDR_T(px_args32.coal_info);
3473 px_args.persona_info_size = px_args32.persona_info_size;
3474 px_args.persona_info = CAST_USER_ADDR_T(px_args32.persona_info);
3475 px_args.posix_cred_info_size = px_args32.posix_cred_info_size;
3476 px_args.posix_cred_info = CAST_USER_ADDR_T(px_args32.posix_cred_info);
3477 px_args.subsystem_root_path_size = px_args32.subsystem_root_path_size;
3478 px_args.subsystem_root_path = CAST_USER_ADDR_T(px_args32.subsystem_root_path);
3479 }
3480 if (error) {
3481 goto bad;
3482 }
3483
3484 if (px_args.attr_size != 0) {
3485 /*
3486 * We are not copying the port_actions pointer,
3487 * because we already have it from px_args.
3488 * This is a bit fragile: <rdar://problem/16427422>
3489 */
3490
3491 if ((error = copyin(px_args.attrp, &px_sa, px_sa_offset)) != 0) {
3492 goto bad;
3493 }
3494
3495 imgp->ip_px_sa = &px_sa;
3496 }
3497 if (px_args.file_actions_size != 0) {
3498 /* Limit file_actions to allowed number of open files */
3499 size_t maxfa_size = PSF_ACTIONS_SIZE(proc_limitgetcur_nofile(p));
3500
3501 if (px_args.file_actions_size < PSF_ACTIONS_SIZE(1) ||
3502 maxfa_size == 0 || px_args.file_actions_size > maxfa_size) {
3503 error = EINVAL;
3504 goto bad;
3505 }
3506
3507 px_sfap = kalloc_data(px_args.file_actions_size, Z_WAITOK);
3508 if (px_sfap == NULL) {
3509 error = ENOMEM;
3510 goto bad;
3511 }
3512 imgp->ip_px_sfa = px_sfap;
3513
3514 if ((error = copyin(px_args.file_actions, px_sfap,
3515 px_args.file_actions_size)) != 0) {
3516 goto bad;
3517 }
3518
3519 /* Verify that the action count matches the struct size */
3520 size_t psfsize = PSF_ACTIONS_SIZE(px_sfap->psfa_act_count);
3521 if (psfsize == 0 || psfsize != px_args.file_actions_size) {
3522 error = EINVAL;
3523 goto bad;
3524 }
3525 }
3526 if (px_args.port_actions_size != 0) {
3527 /* Limit port_actions to one page of data */
3528 if (px_args.port_actions_size < PS_PORT_ACTIONS_SIZE(1) ||
3529 px_args.port_actions_size > PAGE_SIZE) {
3530 error = EINVAL;
3531 goto bad;
3532 }
3533
3534 px_spap = kalloc_data(px_args.port_actions_size, Z_WAITOK);
3535 if (px_spap == NULL) {
3536 error = ENOMEM;
3537 goto bad;
3538 }
3539 imgp->ip_px_spa = px_spap;
3540
3541 if ((error = copyin(px_args.port_actions, px_spap,
3542 px_args.port_actions_size)) != 0) {
3543 goto bad;
3544 }
3545
3546 /* Verify that the action count matches the struct size */
3547 size_t pasize = PS_PORT_ACTIONS_SIZE(px_spap->pspa_count);
3548 if (pasize == 0 || pasize != px_args.port_actions_size) {
3549 error = EINVAL;
3550 goto bad;
3551 }
3552 }
3553 #if CONFIG_PERSONAS
3554 /* copy in the persona info */
3555 if (px_args.persona_info_size != 0 && px_args.persona_info != 0) {
3556 /* for now, we need the exact same struct in user space */
3557 if (px_args.persona_info_size != sizeof(*px_persona)) {
3558 error = ERANGE;
3559 goto bad;
3560 }
3561
3562 px_persona = kalloc_data(px_args.persona_info_size, Z_WAITOK);
3563 if (px_persona == NULL) {
3564 error = ENOMEM;
3565 goto bad;
3566 }
3567 imgp->ip_px_persona = px_persona;
3568
3569 if ((error = copyin(px_args.persona_info, px_persona,
3570 px_args.persona_info_size)) != 0) {
3571 goto bad;
3572 }
3573 if ((error = spawn_validate_persona(px_persona)) != 0) {
3574 goto bad;
3575 }
3576 }
3577 #endif
3578 /* copy in the posix cred info */
3579 if (px_args.posix_cred_info_size != 0 && px_args.posix_cred_info != 0) {
3580 /* for now, we need the exact same struct in user space */
3581 if (px_args.posix_cred_info_size != sizeof(*px_pcred_info)) {
3582 error = ERANGE;
3583 goto bad;
3584 }
3585
3586 if (!kauth_cred_issuser(kauth_cred_get())) {
3587 error = EPERM;
3588 goto bad;
3589 }
3590
3591 px_pcred_info = kalloc_data(px_args.posix_cred_info_size, Z_WAITOK);
3592 if (px_pcred_info == NULL) {
3593 error = ENOMEM;
3594 goto bad;
3595 }
3596 imgp->ip_px_pcred_info = px_pcred_info;
3597
3598 if ((error = copyin(px_args.posix_cred_info, px_pcred_info,
3599 px_args.posix_cred_info_size)) != 0) {
3600 goto bad;
3601 }
3602
3603 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
3604 if (px_pcred_info->pspci_ngroups > NGROUPS_MAX) {
3605 error = EINVAL;
3606 goto bad;
3607 }
3608 }
3609 }
3610 #if CONFIG_MACF
3611 if (px_args.mac_extensions_size != 0) {
3612 if ((error = spawn_copyin_macpolicyinfo(&px_args, (struct ip_px_smpx_s *)&imgp->ip_px_smpx)) != 0) {
3613 goto bad;
3614 }
3615 }
3616 #endif /* CONFIG_MACF */
3617 if ((px_args.subsystem_root_path_size > 0) && (px_args.subsystem_root_path_size <= MAXPATHLEN)) {
3618 /*
3619 * If a valid-looking subsystem root has been
3620 * specified...
3621 */
3622 if (IOTaskHasEntitlement(old_task, SPAWN_SUBSYSTEM_ROOT_ENTITLEMENT)) {
3623 /*
3624 * ...AND the parent has the entitlement, copy
3625 * the subsystem root path in.
3626 */
3627 subsystem_root_path = zalloc_flags(ZV_NAMEI,
3628 Z_WAITOK | Z_ZERO | Z_NOFAIL);
3629
3630 if ((error = copyin(px_args.subsystem_root_path, subsystem_root_path, px_args.subsystem_root_path_size))) {
3631 goto bad;
3632 }
3633
3634 /* Paranoia */
3635 subsystem_root_path[px_args.subsystem_root_path_size - 1] = 0;
3636 }
3637 }
3638 }
3639
3640 if (IOTaskHasEntitlement(old_task, SPAWN_SET_PANIC_CRASH_BEHAVIOR)) {
3641 /* Truncate to uint8_t since we only support 2 flags for now */
3642 crash_behavior = (uint8_t)px_sa.psa_crash_behavior;
3643 crash_behavior_deadline = px_sa.psa_crash_behavior_deadline;
3644 }
3645
3646 /* set uthread to parent */
3647 uthread = current_uthread();
3648
3649 /*
3650 * <rdar://6640530>; this does not result in a behaviour change
3651 * relative to Leopard, so there should not be any existing code
3652 * which depends on it.
3653 */
3654
3655 if (imgp->ip_px_sa != NULL) {
3656 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
3657 if ((psa->psa_options & PSA_OPTION_PLUGIN_HOST_DISABLE_A_KEYS) == PSA_OPTION_PLUGIN_HOST_DISABLE_A_KEYS) {
3658 imgp->ip_flags |= IMGPF_PLUGIN_HOST_DISABLE_A_KEYS;
3659 }
3660 #if (DEVELOPMENT || DEBUG)
3661 if ((psa->psa_options & PSA_OPTION_ALT_ROSETTA) == PSA_OPTION_ALT_ROSETTA) {
3662 imgp->ip_flags |= (IMGPF_ROSETTA | IMGPF_ALT_ROSETTA);
3663 }
3664 #endif
3665
3666 if ((error = exec_validate_spawnattr_policy(psa->psa_apptype)) != 0) {
3667 goto bad;
3668 }
3669 }
3670
3671 /*
3672 * If we don't have the extension flag that turns "posix_spawn()"
3673 * into "execve() with options", then we will be creating a new
3674 * process which does not inherit memory from the parent process,
3675 * which is one of the most expensive things about using fork()
3676 * and execve().
3677 */
3678 if (imgp->ip_px_sa == NULL || !(px_sa.psa_flags & POSIX_SPAWN_SETEXEC)) {
3679 /* Set the new task's coalition, if it is requested. */
3680 coalition_t coal[COALITION_NUM_TYPES] = { COALITION_NULL };
3681 #if CONFIG_COALITIONS
3682 int i, ncoals;
3683 kern_return_t kr = KERN_SUCCESS;
3684 struct _posix_spawn_coalition_info coal_info;
3685 int coal_role[COALITION_NUM_TYPES];
3686
3687 if (imgp->ip_px_sa == NULL || !px_args.coal_info) {
3688 goto do_fork1;
3689 }
3690
3691 memset(&coal_info, 0, sizeof(coal_info));
3692
3693 if (px_args.coal_info_size > sizeof(coal_info)) {
3694 px_args.coal_info_size = sizeof(coal_info);
3695 }
3696 error = copyin(px_args.coal_info,
3697 &coal_info, px_args.coal_info_size);
3698 if (error != 0) {
3699 goto bad;
3700 }
3701
3702 ncoals = 0;
3703 for (i = 0; i < COALITION_NUM_TYPES; i++) {
3704 uint64_t cid = coal_info.psci_info[i].psci_id;
3705 if (cid != 0) {
3706 /*
3707 * don't allow tasks which are not in a
3708 * privileged coalition to spawn processes
3709 * into coalitions other than their own
3710 */
3711 if (!task_is_in_privileged_coalition(proc_task(p), i) &&
3712 !IOTaskHasEntitlement(proc_task(p), COALITION_SPAWN_ENTITLEMENT)) {
3713 coal_dbg("ERROR: %d not in privilegd "
3714 "coalition of type %d",
3715 proc_getpid(p), i);
3716 spawn_coalitions_release_all(coal);
3717 error = EPERM;
3718 goto bad;
3719 }
3720
3721 coal_dbg("searching for coalition id:%llu", cid);
3722 /*
3723 * take a reference and activation on the
3724 * coalition to guard against free-while-spawn
3725 * races
3726 */
3727 coal[i] = coalition_find_and_activate_by_id(cid);
3728 if (coal[i] == COALITION_NULL) {
3729 coal_dbg("could not find coalition id:%llu "
3730 "(perhaps it has been terminated or reaped)", cid);
3731 /*
3732 * release any other coalition's we
3733 * may have a reference to
3734 */
3735 spawn_coalitions_release_all(coal);
3736 error = ESRCH;
3737 goto bad;
3738 }
3739 if (coalition_type(coal[i]) != i) {
3740 coal_dbg("coalition with id:%lld is not of type:%d"
3741 " (it's type:%d)", cid, i, coalition_type(coal[i]));
3742 spawn_coalitions_release_all(coal);
3743 error = ESRCH;
3744 goto bad;
3745 }
3746 coal_role[i] = coal_info.psci_info[i].psci_role;
3747 ncoals++;
3748 }
3749 }
3750 if (ncoals < COALITION_NUM_TYPES) {
3751 /*
3752 * If the user is attempting to spawn into a subset of
3753 * the known coalition types, then make sure they have
3754 * _at_least_ specified a resource coalition. If not,
3755 * the following fork1() call will implicitly force an
3756 * inheritance from 'p' and won't actually spawn the
3757 * new task into the coalitions the user specified.
3758 * (also the call to coalitions_set_roles will panic)
3759 */
3760 if (coal[COALITION_TYPE_RESOURCE] == COALITION_NULL) {
3761 spawn_coalitions_release_all(coal);
3762 error = EINVAL;
3763 goto bad;
3764 }
3765 }
3766 do_fork1:
3767 #endif /* CONFIG_COALITIONS */
3768
3769 /*
3770 * note that this will implicitly inherit the
3771 * caller's persona (if it exists)
3772 */
3773 error = fork1(p, &imgp->ip_new_thread, PROC_CREATE_SPAWN, coal);
3774 /* returns a thread and task reference */
3775
3776 if (error == 0) {
3777 new_task = get_threadtask(imgp->ip_new_thread);
3778 }
3779 #if CONFIG_COALITIONS
3780 /* set the roles of this task within each given coalition */
3781 if (error == 0) {
3782 kr = coalitions_set_roles(coal, new_task, coal_role);
3783 if (kr != KERN_SUCCESS) {
3784 error = EINVAL;
3785 }
3786 if (kdebug_debugid_enabled(MACHDBG_CODE(DBG_MACH_COALITION,
3787 MACH_COALITION_ADOPT))) {
3788 for (i = 0; i < COALITION_NUM_TYPES; i++) {
3789 if (coal[i] != COALITION_NULL) {
3790 /*
3791 * On 32-bit targets, uniqueid
3792 * will get truncated to 32 bits
3793 */
3794 KDBG_RELEASE(MACHDBG_CODE(
3795 DBG_MACH_COALITION,
3796 MACH_COALITION_ADOPT),
3797 coalition_id(coal[i]),
3798 get_task_uniqueid(new_task));
3799 }
3800 }
3801 }
3802 }
3803
3804 /* drop our references and activations - fork1() now holds them */
3805 spawn_coalitions_release_all(coal);
3806 #endif /* CONFIG_COALITIONS */
3807 if (error != 0) {
3808 goto bad;
3809 }
3810 imgp->ip_flags |= IMGPF_SPAWN; /* spawn w/o exec */
3811 spawn_no_exec = TRUE; /* used in later tests */
3812 } else {
3813 /* Adjust the user proc count */
3814 (void)chgproccnt(kauth_getruid(), 1);
3815 /*
3816 * For execve case, create a new proc, task and thread
3817 * but don't make the proc visible to userland. After
3818 * image activation, the new proc would take place of
3819 * the old proc in pid hash and other lists that make
3820 * the proc visible to the system.
3821 */
3822 imgp->ip_new_thread = cloneproc(old_task, NULL, p, CLONEPROC_FLAGS_FOR_EXEC);
3823
3824 /* task and thread ref returned by cloneproc */
3825 if (imgp->ip_new_thread == NULL) {
3826 (void)chgproccnt(kauth_getruid(), -1);
3827 error = ENOMEM;
3828 goto bad;
3829 }
3830
3831 new_task = get_threadtask(imgp->ip_new_thread);
3832 imgp->ip_flags |= IMGPF_EXEC;
3833 }
3834
3835 p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
3836
3837 if (spawn_no_exec) {
3838 /*
3839 * We had to wait until this point before firing the
3840 * proc:::create probe, otherwise p would not point to the
3841 * child process.
3842 */
3843 DTRACE_PROC1(create, proc_t, p);
3844 }
3845 assert(p != NULL);
3846
3847 if (subsystem_root_path) {
3848 /* If a subsystem root was specified, swap it in */
3849 char * old_subsystem_root_path = p->p_subsystem_root_path;
3850 p->p_subsystem_root_path = subsystem_root_path;
3851 subsystem_root_path = old_subsystem_root_path;
3852 }
3853
3854 p->p_crash_behavior = crash_behavior;
3855 p->p_crash_behavior_deadline = crash_behavior_deadline;
3856
3857 p->p_crash_count = px_sa.psa_crash_count;
3858 p->p_throttle_timeout = px_sa.psa_throttle_timeout;
3859
3860 /* We'll need the subsystem root for setting up Apple strings */
3861 imgp->ip_subsystem_root_path = p->p_subsystem_root_path;
3862
3863 context.vc_thread = imgp->ip_new_thread;
3864 context.vc_ucred = proc_ucred(p); /* XXX must NOT be kauth_cred_get() */
3865
3866 /*
3867 * Post fdt_fork(), pre exec_handle_sugid() - this is where we want
3868 * to handle the file_actions.
3869 */
3870
3871 /* Has spawn file actions? */
3872 if (imgp->ip_px_sfa != NULL) {
3873 /*
3874 * The POSIX_SPAWN_CLOEXEC_DEFAULT flag
3875 * is handled in exec_handle_file_actions().
3876 */
3877 #if CONFIG_AUDIT
3878 /*
3879 * The file actions auditing can overwrite the upath of
3880 * AUE_POSIX_SPAWN audit record. Save the audit record.
3881 */
3882 struct kaudit_record *save_uu_ar = uthread->uu_ar;
3883 uthread->uu_ar = NULL;
3884 #endif
3885 error = exec_handle_file_actions(imgp,
3886 imgp->ip_px_sa != NULL ? px_sa.psa_flags : 0);
3887 #if CONFIG_AUDIT
3888 /* Restore the AUE_POSIX_SPAWN audit record. */
3889 uthread->uu_ar = save_uu_ar;
3890 #endif
3891 if (error != 0) {
3892 goto bad;
3893 }
3894 }
3895
3896 /* Has spawn port actions? */
3897 if (imgp->ip_px_spa != NULL) {
3898 #if CONFIG_AUDIT
3899 /*
3900 * Do the same for the port actions as we did for the file
3901 * actions. Save the AUE_POSIX_SPAWN audit record.
3902 */
3903 struct kaudit_record *save_uu_ar = uthread->uu_ar;
3904 uthread->uu_ar = NULL;
3905 #endif
3906 error = exec_handle_port_actions(imgp, &port_actions);
3907 #if CONFIG_AUDIT
3908 /* Restore the AUE_POSIX_SPAWN audit record. */
3909 uthread->uu_ar = save_uu_ar;
3910 #endif
3911 if (error != 0) {
3912 goto bad;
3913 }
3914 }
3915
3916 /* Has spawn attr? */
3917 if (imgp->ip_px_sa != NULL) {
3918 /*
3919 * Reset UID/GID to parent's RUID/RGID; This works only
3920 * because the operation occurs before the call
3921 * to exec_handle_sugid() by the image activator called
3922 * from exec_activate_image().
3923 *
3924 * POSIX requires that any setuid/setgid bits on the process
3925 * image will take precedence over the spawn attributes
3926 * (re)setting them.
3927 *
3928 * Modifications to p_ucred must be guarded using the
3929 * proc's ucred lock. This prevents others from accessing
3930 * a garbage credential.
3931 */
3932 if (px_sa.psa_flags & POSIX_SPAWN_RESETIDS) {
3933 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred){
3934 return kauth_cred_setuidgid(my_cred,
3935 kauth_cred_getruid(my_cred),
3936 kauth_cred_getrgid(my_cred));
3937 });
3938 }
3939
3940 if (imgp->ip_px_pcred_info) {
3941 if (!spawn_no_exec) {
3942 error = ENOTSUP;
3943 goto bad;
3944 }
3945
3946 error = spawn_posix_cred_adopt(p, imgp->ip_px_pcred_info);
3947 if (error != 0) {
3948 goto bad;
3949 }
3950 }
3951
3952 #if CONFIG_PERSONAS
3953 if (imgp->ip_px_persona != NULL) {
3954 if (!spawn_no_exec) {
3955 error = ENOTSUP;
3956 goto bad;
3957 }
3958
3959 /*
3960 * If we were asked to spawn a process into a new persona,
3961 * do the credential switch now (which may override the UID/GID
3962 * inherit done just above). It's important to do this switch
3963 * before image activation both for reasons stated above, and
3964 * to ensure that the new persona has access to the image/file
3965 * being executed.
3966 */
3967 error = spawn_persona_adopt(p, imgp->ip_px_persona);
3968 if (error != 0) {
3969 goto bad;
3970 }
3971 }
3972 #endif /* CONFIG_PERSONAS */
3973 #if !SECURE_KERNEL
3974 /*
3975 * Disable ASLR for the spawned process.
3976 *
3977 * But only do so if we are not embedded + RELEASE.
3978 * While embedded allows for a boot-arg (-disable_aslr)
3979 * to deal with this (which itself is only honored on
3980 * DEVELOPMENT or DEBUG builds of xnu), it is often
3981 * useful or necessary to disable ASLR on a per-process
3982 * basis for unit testing and debugging.
3983 */
3984 if (px_sa.psa_flags & _POSIX_SPAWN_DISABLE_ASLR) {
3985 OSBitOrAtomic(P_DISABLE_ASLR, &p->p_flag);
3986 }
3987 #endif /* !SECURE_KERNEL */
3988
3989 /* Randomize high bits of ASLR slide */
3990 if (px_sa.psa_flags & _POSIX_SPAWN_HIGH_BITS_ASLR) {
3991 imgp->ip_flags |= IMGPF_HIGH_BITS_ASLR;
3992 }
3993
3994 #if !SECURE_KERNEL
3995 /*
3996 * Forcibly disallow execution from data pages for the spawned process
3997 * even if it would otherwise be permitted by the architecture default.
3998 */
3999 if (px_sa.psa_flags & _POSIX_SPAWN_ALLOW_DATA_EXEC) {
4000 imgp->ip_flags |= IMGPF_ALLOW_DATA_EXEC;
4001 }
4002 #endif /* !SECURE_KERNEL */
4003
4004 #if __has_feature(ptrauth_calls)
4005 if (vm_shared_region_reslide_aslr && is_64 && (px_sa.psa_flags & _POSIX_SPAWN_RESLIDE)) {
4006 imgp->ip_flags |= IMGPF_RESLIDE;
4007 }
4008 #endif /* __has_feature(ptrauth_calls) */
4009
4010 if ((px_sa.psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) ==
4011 POSIX_SPAWN_PROC_TYPE_DRIVER) {
4012 imgp->ip_flags |= IMGPF_DRIVER;
4013 }
4014 }
4015
4016 /*
4017 * Disable ASLR during image activation. This occurs either if the
4018 * _POSIX_SPAWN_DISABLE_ASLR attribute was found above or if
4019 * P_DISABLE_ASLR was inherited from the parent process.
4020 */
4021 if (p->p_flag & P_DISABLE_ASLR) {
4022 imgp->ip_flags |= IMGPF_DISABLE_ASLR;
4023 }
4024
4025 /*
4026 * Clear transition flag so we won't hang if exec_activate_image() causes
4027 * an automount (and launchd does a proc sysctl to service it).
4028 *
4029 * <rdar://problem/6848672>, <rdar://problem/5959568>.
4030 */
4031 proc_transend(p, 0);
4032 proc_transit_set = 0;
4033
4034 if (!spawn_no_exec) {
4035 /*
4036 * Clear the signal lock in case of exec, since
4037 * image activation uses psignal on child process.
4038 */
4039 proc_signalend(p, 0);
4040 proc_signal_set = 0;
4041 }
4042
4043 #if MAC_SPAWN /* XXX */
4044 if (uap->mac_p != USER_ADDR_NULL) {
4045 error = mac_execve_enter(uap->mac_p, imgp);
4046 if (error) {
4047 goto bad;
4048 }
4049 }
4050 #endif
4051
4052 /*
4053 * Activate the image.
4054 * Warning: If activation failed after point of no return, it returns error
4055 * as 0 and pretends the call succeeded.
4056 */
4057 error = exec_activate_image(imgp);
4058 #if defined(HAS_APPLE_PAC)
4059 ml_task_set_jop_pid_from_shared_region(new_task);
4060 ml_task_set_disable_user_jop(new_task, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
4061 ml_thread_set_disable_user_jop(imgp->ip_new_thread, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
4062 ml_thread_set_jop_pid(imgp->ip_new_thread, new_task);
4063 #endif
4064
4065 /*
4066 * If you've come here to add support for some new HW feature or some per-process or per-vmmap
4067 * or per-pmap flag that needs to be set before the process runs, or are in general lost, here
4068 * is some help. This summary was accurate as of Jul 2022. Use git log as needed. This comment
4069 * is here to prevent a recurrence of rdar://96307913
4070 *
4071 * In posix_spawn, following is what happens:
4072 * 1. Lots of prep and checking work
4073 * 2. Image activation via exec_activate_image(). The new task will get a new pmap here
4074 * 3. More prep work. (YOU ARE HERE)
4075 * 4. exec_resettextvp() is called
4076 * 5. At this point it is safe to check entitlements and code signatures
4077 * 6. task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
4078 * The new thread is allowed to run in kernel. It cannot yet get to userland
4079 * 7. More things done here. This is your chance to affect the task before it runs in
4080 * userspace
4081 * 8. task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
4082 * The new thread is allowed to run in userland
4083 */
4084
4085 if (error == 0 && !spawn_no_exec) {
4086 p = proc_exec_switch_task(current_proc(), p, old_task, new_task, imgp->ip_new_thread, &inherit);
4087 /* proc ref returned */
4088 should_release_proc_ref = TRUE;
4089 }
4090
4091 if (error == 0) {
4092 /* process completed the exec, but may have failed after point of no return */
4093 exec_done = TRUE;
4094 /*
4095 * Enable new task IPC access if exec_activate_image() returned an
4096 * active task. (Checks active bit in ipc_task_enable() under lock).
4097 */
4098 ipc_task_enable(new_task);
4099 }
4100
4101 if (!error && imgp->ip_px_sa != NULL) {
4102 thread_t child_thread = imgp->ip_new_thread;
4103 uthread_t child_uthread = get_bsdthread_info(child_thread);
4104
4105 /*
4106 * Because of POSIX_SPAWN_SETEXEC, we need to handle this after image
4107 * activation, else when image activation fails (before the point of no
4108 * return) would leave the parent process in a modified state.
4109 */
4110 if (px_sa.psa_flags & POSIX_SPAWN_SETPGROUP) {
4111 struct setpgid_args spga;
4112 spga.pid = proc_getpid(p);
4113 spga.pgid = px_sa.psa_pgroup;
4114 /*
4115 * Effectively, call setpgid() system call; works
4116 * because there are no pointer arguments.
4117 */
4118 if ((error = setpgid(p, &spga, ival)) != 0) {
4119 goto bad;
4120 }
4121 }
4122
4123 if (px_sa.psa_flags & POSIX_SPAWN_SETSID) {
4124 error = setsid_internal(p);
4125 if (error != 0) {
4126 goto bad;
4127 }
4128 }
4129
4130 /*
4131 * If we have a spawn attr, and it contains signal related flags,
4132 * the we need to process them in the "context" of the new child
4133 * process, so we have to process it following image activation,
4134 * prior to making the thread runnable in user space. This is
4135 * necessitated by some signal information being per-thread rather
4136 * than per-process, and we don't have the new allocation in hand
4137 * until after the image is activated.
4138 */
4139
4140 /*
4141 * Mask a list of signals, instead of them being unmasked, if
4142 * they were unmasked in the parent; note that some signals
4143 * are not maskable.
4144 */
4145 if (px_sa.psa_flags & POSIX_SPAWN_SETSIGMASK) {
4146 child_uthread->uu_sigmask = (px_sa.psa_sigmask & ~sigcantmask);
4147 }
4148 /*
4149 * Default a list of signals instead of ignoring them, if
4150 * they were ignored in the parent. Note that we pass
4151 * spawn_no_exec to setsigvec() to indicate that we called
4152 * fork1() and therefore do not need to call proc_signalstart()
4153 * internally.
4154 */
4155 if (px_sa.psa_flags & POSIX_SPAWN_SETSIGDEF) {
4156 vec.sa_handler = SIG_DFL;
4157 vec.sa_tramp = 0;
4158 vec.sa_mask = 0;
4159 vec.sa_flags = 0;
4160 for (sig = 1; sig < NSIG; sig++) {
4161 if (px_sa.psa_sigdefault & (1 << (sig - 1))) {
4162 error = setsigvec(p, child_thread, sig, &vec, spawn_no_exec);
4163 }
4164 }
4165 }
4166
4167 /*
4168 * Activate the CPU usage monitor, if requested. This is done via a task-wide, per-thread CPU
4169 * usage limit, which will generate a resource exceeded exception if any one thread exceeds the
4170 * limit.
4171 *
4172 * Userland gives us interval in seconds, and the kernel SPI expects nanoseconds.
4173 */
4174 if ((px_sa.psa_cpumonitor_percent != 0) && (px_sa.psa_cpumonitor_percent < UINT8_MAX)) {
4175 /*
4176 * Always treat a CPU monitor activation coming from spawn as entitled. Requiring
4177 * an entitlement to configure the monitor a certain way seems silly, since
4178 * whomever is turning it on could just as easily choose not to do so.
4179 */
4180 error = proc_set_task_ruse_cpu(proc_task(p),
4181 TASK_POLICY_RESOURCE_ATTRIBUTE_NOTIFY_EXC,
4182 (uint8_t)px_sa.psa_cpumonitor_percent,
4183 px_sa.psa_cpumonitor_interval * NSEC_PER_SEC,
4184 0, TRUE);
4185 }
4186
4187
4188 if (px_pcred_info &&
4189 (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_LOGIN)) {
4190 /*
4191 * setlogin() must happen after setsid()
4192 */
4193 setlogin_internal(p, px_pcred_info->pspci_login);
4194 }
4195 }
4196
4197 bad:
4198
4199 if (error == 0) {
4200 /* reset delay idle sleep status if set */
4201 #if CONFIG_DELAY_IDLE_SLEEP
4202 if ((p->p_flag & P_DELAYIDLESLEEP) == P_DELAYIDLESLEEP) {
4203 OSBitAndAtomic(~((uint32_t)P_DELAYIDLESLEEP), &p->p_flag);
4204 }
4205 #endif /* CONFIG_DELAY_IDLE_SLEEP */
4206 /* upon successful spawn, re/set the proc control state */
4207 if (imgp->ip_px_sa != NULL) {
4208 switch (px_sa.psa_pcontrol) {
4209 case POSIX_SPAWN_PCONTROL_THROTTLE:
4210 p->p_pcaction = P_PCTHROTTLE;
4211 break;
4212 case POSIX_SPAWN_PCONTROL_SUSPEND:
4213 p->p_pcaction = P_PCSUSP;
4214 break;
4215 case POSIX_SPAWN_PCONTROL_KILL:
4216 p->p_pcaction = P_PCKILL;
4217 break;
4218 case POSIX_SPAWN_PCONTROL_NONE:
4219 default:
4220 p->p_pcaction = 0;
4221 break;
4222 }
4223 ;
4224 }
4225 exec_resettextvp(p, imgp);
4226
4227 #if CONFIG_MEMORYSTATUS
4228 /* Set jetsam priority for DriverKit processes */
4229 if (px_sa.psa_apptype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
4230 px_sa.psa_priority = JETSAM_PRIORITY_DRIVER_APPLE;
4231 }
4232
4233 /* Has jetsam attributes? */
4234 if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_SET)) {
4235 /*
4236 * With 2-level high-water-mark support, POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is no
4237 * longer relevant, as background limits are described via the inactive limit slots.
4238 *
4239 * That said, however, if the POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is passed in,
4240 * we attempt to mimic previous behavior by forcing the BG limit data into the
4241 * inactive/non-fatal mode and force the active slots to hold system_wide/fatal mode.
4242 */
4243
4244 if (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND) {
4245 memorystatus_update(p, px_sa.psa_priority, 0, FALSE, /* assertion priority */
4246 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY),
4247 TRUE,
4248 -1, TRUE,
4249 px_sa.psa_memlimit_inactive, FALSE);
4250 } else {
4251 memorystatus_update(p, px_sa.psa_priority, 0, FALSE, /* assertion priority */
4252 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY),
4253 TRUE,
4254 px_sa.psa_memlimit_active,
4255 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_ACTIVE_FATAL),
4256 px_sa.psa_memlimit_inactive,
4257 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_INACTIVE_FATAL));
4258 }
4259 }
4260
4261 /* Has jetsam relaunch behavior? */
4262 if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK)) {
4263 /*
4264 * Launchd has passed in data indicating the behavior of this process in response to jetsam.
4265 * This data would be used by the jetsam subsystem to determine the position and protection
4266 * offered to this process on dirty -> clean transitions.
4267 */
4268 int relaunch_flags = P_MEMSTAT_RELAUNCH_UNKNOWN;
4269 switch (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK) {
4270 case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_LOW:
4271 relaunch_flags = P_MEMSTAT_RELAUNCH_LOW;
4272 break;
4273 case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MED:
4274 relaunch_flags = P_MEMSTAT_RELAUNCH_MED;
4275 break;
4276 case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_HIGH:
4277 relaunch_flags = P_MEMSTAT_RELAUNCH_HIGH;
4278 break;
4279 default:
4280 break;
4281 }
4282 memorystatus_relaunch_flags_update(p, relaunch_flags);
4283 }
4284
4285 #endif /* CONFIG_MEMORYSTATUS */
4286 if (imgp->ip_px_sa != NULL && px_sa.psa_thread_limit > 0) {
4287 task_set_thread_limit(new_task, (uint16_t)px_sa.psa_thread_limit);
4288 }
4289
4290 #if CONFIG_PROC_RESOURCE_LIMITS
4291 if (imgp->ip_px_sa != NULL && (px_sa.psa_port_soft_limit > 0 || px_sa.psa_port_hard_limit > 0)) {
4292 task_set_port_space_limits(new_task, (uint32_t)px_sa.psa_port_soft_limit,
4293 (uint32_t)px_sa.psa_port_hard_limit);
4294 }
4295
4296 if (imgp->ip_px_sa != NULL && (px_sa.psa_filedesc_soft_limit > 0 || px_sa.psa_filedesc_hard_limit > 0)) {
4297 proc_set_filedesc_limits(p, (int)px_sa.psa_filedesc_soft_limit,
4298 (int)px_sa.psa_filedesc_hard_limit);
4299 }
4300 #endif /* CONFIG_PROC_RESOURCE_LIMITS */
4301
4302 /* Disable wakeup monitoring for DriverKit processes */
4303 if (px_sa.psa_apptype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
4304 uint32_t flags = WAKEMON_DISABLE;
4305 task_wakeups_monitor_ctl(new_task, &flags, NULL);
4306 }
4307 }
4308
4309 /*
4310 * If we successfully called fork1() or cloneproc, we always need
4311 * to do this. This is because we come back from that call with
4312 * signals blocked in the child, and we have to unblock them, for exec
4313 * case they are unblocked before activation, but for true spawn case
4314 * we want to wait until after we've performed any spawn actions.
4315 * This has to happen before process_signature(), which uses psignal.
4316 */
4317 if (proc_transit_set) {
4318 proc_transend(p, 0);
4319 }
4320
4321 /*
4322 * Drop the signal lock on the child which was taken on our
4323 * behalf by forkproc()/cloneproc() to prevent signals being
4324 * received by the child in a partially constructed state.
4325 */
4326 if (proc_signal_set) {
4327 proc_signalend(p, 0);
4328 }
4329
4330 if (error == 0) {
4331 /*
4332 * We need to initialize the bank context behind the protection of
4333 * the proc_trans lock to prevent a race with exit. We can't do this during
4334 * exec_activate_image because task_bank_init checks entitlements that
4335 * aren't loaded until subsequent calls (including exec_resettextvp).
4336 */
4337 error = proc_transstart(p, 0, 0);
4338
4339 if (error == 0) {
4340 task_bank_init(new_task);
4341 proc_transend(p, 0);
4342 }
4343
4344 #if __arm64__
4345 proc_footprint_entitlement_hacks(p, new_task);
4346 #endif /* __arm64__ */
4347
4348 #if XNU_TARGET_OS_OSX
4349 #define SINGLE_JIT_ENTITLEMENT "com.apple.security.cs.single-jit"
4350 if (IOTaskHasEntitlement(new_task, SINGLE_JIT_ENTITLEMENT)) {
4351 vm_map_single_jit(get_task_map(new_task));
4352 }
4353 #endif /* XNU_TARGET_OS_OSX */
4354
4355 #if __has_feature(ptrauth_calls)
4356 task_set_pac_exception_fatal_flag(new_task);
4357 #endif /* __has_feature(ptrauth_calls) */
4358 }
4359
4360 /* Inherit task role from old task to new task for exec */
4361 if (error == 0 && !spawn_no_exec) {
4362 proc_inherit_task_role(new_task, old_task);
4363 }
4364
4365 #if CONFIG_ARCADE
4366 if (error == 0) {
4367 /*
4368 * Check to see if we need to trigger an arcade upcall AST now
4369 * that the vnode has been reset on the task.
4370 */
4371 arcade_prepare(new_task, imgp->ip_new_thread);
4372 }
4373 #endif /* CONFIG_ARCADE */
4374
4375 #if CONFIG_MACF
4376 if (error == 0) {
4377 proc_apply_jit_and_jumbo_va_policies(p, new_task);
4378 }
4379 #endif /* CONFIG_MACF */
4380
4381 /* Clear the initial wait on the thread before handling spawn policy */
4382 if (imgp && imgp->ip_new_thread) {
4383 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
4384 }
4385
4386 /*
4387 * Apply the spawnattr policy, apptype (which primes the task for importance donation),
4388 * and bind any portwatch ports to the new task.
4389 * This must be done after the exec so that the child's thread is ready,
4390 * and after the in transit state has been released, because priority is
4391 * dropped here so we need to be prepared for a potentially long preemption interval
4392 *
4393 * TODO: Consider splitting this up into separate phases
4394 */
4395 if (error == 0 && imgp->ip_px_sa != NULL) {
4396 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4397
4398 error = exec_handle_spawnattr_policy(p, imgp->ip_new_thread, psa->psa_apptype, psa->psa_qos_clamp,
4399 psa->psa_darwin_role, &port_actions);
4400 }
4401
4402 /* Transfer the turnstile watchport boost to new task if in exec */
4403 if (error == 0 && !spawn_no_exec) {
4404 task_transfer_turnstile_watchports(old_task, new_task, imgp->ip_new_thread);
4405 }
4406
4407 /*
4408 * Apply the requested maximum address.
4409 */
4410 if (error == 0 && imgp->ip_px_sa != NULL) {
4411 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4412
4413 if (psa->psa_max_addr) {
4414 vm_map_set_max_addr(get_task_map(new_task), (vm_map_offset_t)psa->psa_max_addr);
4415 }
4416 }
4417
4418 if (error == 0 && imgp->ip_px_sa != NULL) {
4419 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4420
4421 if (psa->psa_no_smt) {
4422 task_set_no_smt(new_task);
4423 }
4424 if (psa->psa_tecs) {
4425 task_set_tecs(new_task);
4426 }
4427 }
4428
4429 if (error == 0) {
4430 /* Apply the main thread qos */
4431 thread_t main_thread = imgp->ip_new_thread;
4432 task_set_main_thread_qos(new_task, main_thread);
4433 proc_apply_tpro(imgp, new_task);
4434
4435 #if CONFIG_MAP_RANGES
4436 proc_apply_vm_range_policies(p, new_task);
4437 #endif /* CONFIG_MAP_RANGES */
4438 }
4439
4440 /*
4441 * Release any ports we kept around for binding to the new task
4442 * We need to release the rights even if the posix_spawn has failed.
4443 */
4444 if (imgp->ip_px_spa != NULL) {
4445 exec_port_actions_destroy(&port_actions);
4446 }
4447
4448 /*
4449 * We have to delay operations which might throw a signal until after
4450 * the signals have been unblocked; however, we want that to happen
4451 * after exec_resettextvp() so that the textvp is correct when they
4452 * fire.
4453 */
4454 if (error == 0) {
4455 error = process_signature(p, imgp);
4456
4457 /*
4458 * Pay for our earlier safety; deliver the delayed signals from
4459 * the incomplete spawn process now that it's complete.
4460 */
4461 if (imgp != NULL && spawn_no_exec && (p->p_lflag & P_LTRACED)) {
4462 psignal_vfork(p, proc_task(p), imgp->ip_new_thread, SIGTRAP);
4463 }
4464
4465 if (error == 0 && !spawn_no_exec) {
4466 KDBG(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXEC),
4467 proc_getpid(p));
4468 }
4469 }
4470
4471 if (spawn_no_exec) {
4472 /* flag the 'fork' has occurred */
4473 proc_knote(p->p_pptr, NOTE_FORK | proc_getpid(p));
4474 }
4475
4476 /* flag exec has occurred, notify only if it has not failed due to FP Key error */
4477 if (!error && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
4478 proc_knote(p, NOTE_EXEC);
4479 }
4480
4481 if (imgp != NULL) {
4482 uthread_set_exec_data(current_uthread(), NULL);
4483 if (imgp->ip_vp) {
4484 vnode_put(imgp->ip_vp);
4485 }
4486 if (imgp->ip_scriptvp) {
4487 vnode_put(imgp->ip_scriptvp);
4488 }
4489 if (imgp->ip_strings) {
4490 execargs_free(imgp);
4491 }
4492 kfree_data(imgp->ip_px_sfa,
4493 px_args.file_actions_size);
4494 kfree_data(imgp->ip_px_spa,
4495 px_args.port_actions_size);
4496 #if CONFIG_PERSONAS
4497 kfree_data(imgp->ip_px_persona,
4498 px_args.persona_info_size);
4499 #endif
4500 kfree_data(imgp->ip_px_pcred_info,
4501 px_args.posix_cred_info_size);
4502
4503 if (subsystem_root_path != NULL) {
4504 zfree(ZV_NAMEI, subsystem_root_path);
4505 }
4506 #if CONFIG_MACF
4507 struct ip_px_smpx_s *px_s = &imgp->ip_px_smpx;
4508 kfree_data(px_s->array, px_args.mac_extensions_size);
4509 kfree_data(px_s->data, (vm_size_t)px_s->datalen);
4510
4511 if (imgp->ip_execlabelp) {
4512 mac_cred_label_free(imgp->ip_execlabelp);
4513 imgp->ip_execlabelp = NULL;
4514 }
4515 if (imgp->ip_scriptlabelp) {
4516 mac_vnode_label_free(imgp->ip_scriptlabelp);
4517 imgp->ip_scriptlabelp = NULL;
4518 }
4519 if (imgp->ip_cs_error != OS_REASON_NULL) {
4520 os_reason_free(imgp->ip_cs_error);
4521 imgp->ip_cs_error = OS_REASON_NULL;
4522 }
4523 if (imgp->ip_inherited_shared_region_id != NULL) {
4524 kfree_data(imgp->ip_inherited_shared_region_id,
4525 strlen(imgp->ip_inherited_shared_region_id) + 1);
4526 imgp->ip_inherited_shared_region_id = NULL;
4527 }
4528 #endif
4529 }
4530
4531 #if CONFIG_DTRACE
4532 if (spawn_no_exec) {
4533 /*
4534 * In the original DTrace reference implementation,
4535 * posix_spawn() was a libc routine that just
4536 * did vfork(2) then exec(2). Thus the proc::: probes
4537 * are very fork/exec oriented. The details of this
4538 * in-kernel implementation of posix_spawn() is different
4539 * (while producing the same process-observable effects)
4540 * particularly w.r.t. errors, and which thread/process
4541 * is constructing what on behalf of whom.
4542 */
4543 if (error) {
4544 DTRACE_PROC1(spawn__failure, int, error);
4545 } else {
4546 DTRACE_PROC(spawn__success);
4547 /*
4548 * Some DTrace scripts, e.g. newproc.d in
4549 * /usr/bin, rely on the the 'exec-success'
4550 * probe being fired in the child after the
4551 * new process image has been constructed
4552 * in order to determine the associated pid.
4553 *
4554 * So, even though the parent built the image
4555 * here, for compatibility, mark the new thread
4556 * so 'exec-success' fires on it as it leaves
4557 * the kernel.
4558 */
4559 dtrace_thread_didexec(imgp->ip_new_thread);
4560 }
4561 } else {
4562 if (error) {
4563 DTRACE_PROC1(exec__failure, int, error);
4564 } else {
4565 dtrace_thread_didexec(imgp->ip_new_thread);
4566 }
4567 }
4568
4569 if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
4570 (*dtrace_proc_waitfor_hook)(p);
4571 }
4572 #endif
4573
4574 #if CONFIG_AUDIT
4575 if (!error && AUDIT_ENABLED() && p) {
4576 /* Add the CDHash of the new process to the audit record */
4577 uint8_t *cdhash = cs_get_cdhash(p);
4578 if (cdhash) {
4579 AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
4580 }
4581 }
4582 #endif
4583
4584 /* terminate the new task if exec failed */
4585 if (new_task != NULL && task_is_exec_copy(new_task)) {
4586 task_terminate_internal(new_task);
4587 }
4588
4589 /* Return to both the parent and the child? */
4590 if (imgp != NULL && spawn_no_exec) {
4591 /*
4592 * If the parent wants the pid, copy it out
4593 */
4594 if (error == 0 && pid != USER_ADDR_NULL) {
4595 _Static_assert(sizeof(pid_t) == 4, "posix_spawn() assumes a 32-bit pid_t");
4596 bool aligned = (pid & 3) == 0;
4597 if (aligned) {
4598 (void)copyout_atomic32(proc_getpid(p), pid);
4599 } else {
4600 (void)suword(pid, proc_getpid(p));
4601 }
4602 }
4603 retval[0] = error;
4604
4605 /*
4606 * If we had an error, perform an internal reap ; this is
4607 * entirely safe, as we have a real process backing us.
4608 */
4609 if (error) {
4610 proc_list_lock();
4611 p->p_listflag |= P_LIST_DEADPARENT;
4612 proc_list_unlock();
4613 proc_lock(p);
4614 /* make sure no one else has killed it off... */
4615 if (p->p_stat != SZOMB && p->exit_thread == NULL) {
4616 p->exit_thread = current_thread();
4617 p->p_posix_spawn_failed = true;
4618 proc_unlock(p);
4619 exit1(p, 1, (int *)NULL);
4620 } else {
4621 /* someone is doing it for us; just skip it */
4622 proc_unlock(p);
4623 }
4624 }
4625 }
4626
4627 /*
4628 * Do not terminate the current task, if proc_exec_switch_task did not
4629 * switch the tasks, terminating the current task without the switch would
4630 * result in loosing the SIGKILL status.
4631 */
4632 if (task_did_exec(old_task)) {
4633 /* Terminate the current task, since exec will start in new task */
4634 task_terminate_internal(old_task);
4635 }
4636
4637 /* Release the thread ref returned by cloneproc/fork1 */
4638 if (imgp != NULL && imgp->ip_new_thread) {
4639 /* wake up the new thread */
4640 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
4641 thread_deallocate(imgp->ip_new_thread);
4642 imgp->ip_new_thread = NULL;
4643 }
4644
4645 /* Release the ref returned by cloneproc/fork1 */
4646 if (new_task) {
4647 task_deallocate(new_task);
4648 new_task = NULL;
4649 }
4650
4651 if (should_release_proc_ref) {
4652 proc_rele(p);
4653 }
4654
4655 kfree_type(typeof(*__spawn_data), __spawn_data);
4656
4657 if (inherit != NULL) {
4658 ipc_importance_release(inherit);
4659 }
4660
4661 return error;
4662 }
4663
4664 /*
4665 * proc_exec_switch_task
4666 *
4667 * Parameters: old_proc proc before exec
4668 * new_proc proc after exec
4669 * old_task task before exec
4670 * new_task task after exec
4671 * new_thread thread in new task
4672 * inherit resulting importance linkage
4673 *
4674 * Returns: proc.
4675 *
4676 * Note: The function will switch proc in pid hash from old proc to new proc.
4677 * The switch needs to happen after draining all proc refs and inside
4678 * a proc list lock. In the case of failure to switch the proc, which
4679 * might happen if the process received a SIGKILL or jetsam killed it,
4680 * it will make sure that the new tasks terminates. User proc ref returned
4681 * to caller.
4682 *
4683 * This function is called after point of no return, in the case
4684 * failure to switch, it will terminate the new task and swallow the
4685 * error and let the terminated process complete exec and die.
4686 */
4687 proc_t
proc_exec_switch_task(proc_t old_proc,proc_t new_proc,task_t old_task,task_t new_task,thread_t new_thread,void ** inherit)4688 proc_exec_switch_task(proc_t old_proc, proc_t new_proc, task_t old_task, task_t new_task, thread_t new_thread,
4689 void **inherit)
4690 {
4691 boolean_t task_active;
4692 boolean_t proc_active;
4693 boolean_t thread_active;
4694 boolean_t reparent_traced_child = FALSE;
4695 thread_t old_thread = current_thread();
4696
4697 thread_set_exec_promotion(old_thread);
4698 old_proc = proc_refdrain_will_exec(old_proc);
4699
4700 new_proc = proc_refdrain_will_exec(new_proc);
4701 /* extra proc ref returned to the caller */
4702
4703 assert(get_threadtask(new_thread) == new_task);
4704 task_active = task_is_active(new_task);
4705 proc_active = !(old_proc->p_lflag & P_LEXIT);
4706
4707 /* Check if the current thread is not aborted due to SIGKILL */
4708 thread_active = thread_is_active(old_thread);
4709
4710 /*
4711 * Do not switch the proc if the new task or proc is already terminated
4712 * as a result of error in exec past point of no return
4713 */
4714 if (proc_active && task_active && thread_active) {
4715 uthread_t new_uthread = get_bsdthread_info(new_thread);
4716 uthread_t old_uthread = current_uthread();
4717
4718 /* Clear dispatchqueue and workloop ast offset */
4719 new_proc->p_dispatchqueue_offset = 0;
4720 new_proc->p_dispatchqueue_serialno_offset = 0;
4721 new_proc->p_dispatchqueue_label_offset = 0;
4722 new_proc->p_return_to_kernel_offset = 0;
4723 new_proc->p_pthread_wq_quantum_offset = 0;
4724
4725 /* If old_proc is session leader, change the leader to new proc */
4726 session_replace_leader(old_proc, new_proc);
4727
4728 proc_lock(old_proc);
4729
4730 /* Copy the signal state, dtrace state and set bsd ast on new thread */
4731 act_set_astbsd(new_thread);
4732 new_uthread->uu_siglist |= old_uthread->uu_siglist;
4733 new_uthread->uu_siglist |= old_proc->p_siglist;
4734 new_uthread->uu_sigwait = old_uthread->uu_sigwait;
4735 new_uthread->uu_sigmask = old_uthread->uu_sigmask;
4736 new_uthread->uu_oldmask = old_uthread->uu_oldmask;
4737 new_uthread->uu_exit_reason = old_uthread->uu_exit_reason;
4738 #if CONFIG_DTRACE
4739 new_uthread->t_dtrace_sig = old_uthread->t_dtrace_sig;
4740 new_uthread->t_dtrace_stop = old_uthread->t_dtrace_stop;
4741 new_uthread->t_dtrace_resumepid = old_uthread->t_dtrace_resumepid;
4742 assert(new_uthread->t_dtrace_scratch == NULL);
4743 new_uthread->t_dtrace_scratch = old_uthread->t_dtrace_scratch;
4744
4745 old_uthread->t_dtrace_sig = 0;
4746 old_uthread->t_dtrace_stop = 0;
4747 old_uthread->t_dtrace_resumepid = 0;
4748 old_uthread->t_dtrace_scratch = NULL;
4749 #endif
4750
4751 #if CONFIG_PROC_UDATA_STORAGE
4752 new_proc->p_user_data = old_proc->p_user_data;
4753 #endif /* CONFIG_PROC_UDATA_STORAGE */
4754
4755 /* Copy the resource accounting info */
4756 thread_copy_resource_info(new_thread, current_thread());
4757
4758 /* Clear the exit reason and signal state on old thread */
4759 old_uthread->uu_exit_reason = NULL;
4760 old_uthread->uu_siglist = 0;
4761
4762 task_set_did_exec_flag(old_task);
4763 task_clear_exec_copy_flag(new_task);
4764
4765 task_copy_fields_for_exec(new_task, old_task);
4766
4767 /* Transfer sandbox filter bits to new_task. */
4768 task_transfer_mach_filter_bits(new_task, old_task);
4769
4770 /*
4771 * Need to transfer pending watch port boosts to the new task
4772 * while still making sure that the old task remains in the
4773 * importance linkage. Create an importance linkage from old task
4774 * to new task, then switch the task importance base of old task
4775 * and new task. After the switch the port watch boost will be
4776 * boosting the new task and new task will be donating importance
4777 * to old task.
4778 */
4779 *inherit = ipc_importance_exec_switch_task(old_task, new_task);
4780
4781 /* Transfer parent's ptrace state to child */
4782 new_proc->p_lflag &= ~(P_LTRACED | P_LSIGEXC | P_LNOATTACH);
4783 new_proc->p_lflag |= (old_proc->p_lflag & (P_LTRACED | P_LSIGEXC | P_LNOATTACH));
4784 new_proc->p_oppid = old_proc->p_oppid;
4785
4786 if (old_proc->p_pptr != new_proc->p_pptr) {
4787 reparent_traced_child = TRUE;
4788 new_proc->p_lflag |= P_LTRACE_WAIT;
4789 }
4790
4791 proc_unlock(old_proc);
4792
4793 /* Update the list of proc knotes */
4794 proc_transfer_knotes(old_proc, new_proc);
4795
4796 /* Update the proc interval timers */
4797 proc_inherit_itimers(old_proc, new_proc);
4798
4799 proc_list_lock();
4800
4801 /* Insert the new proc in child list of parent proc */
4802 p_reparentallchildren(old_proc, new_proc);
4803
4804 /* Switch proc in pid hash */
4805 phash_replace_locked(proc_getpid(old_proc), old_proc, new_proc);
4806
4807 /* Transfer the shadow flag to old proc */
4808 os_atomic_andnot(&new_proc->p_refcount, P_REF_SHADOW, relaxed);
4809 os_atomic_or(&old_proc->p_refcount, P_REF_SHADOW, relaxed);
4810
4811 /* Change init proc if launchd exec */
4812 if (old_proc == initproc) {
4813 /* Take the ref on new proc after proc_refwake_did_exec */
4814 initproc = new_proc;
4815 /* Drop the proc ref on old proc */
4816 proc_rele(old_proc);
4817 }
4818
4819 proc_list_unlock();
4820 } else {
4821 task_terminate_internal(new_task);
4822 }
4823
4824 proc_refwake_did_exec(new_proc);
4825 proc_refwake_did_exec(old_proc);
4826
4827 /* Take a ref on initproc if it changed */
4828 if (new_proc == initproc) {
4829 initproc = proc_ref(new_proc, false);
4830 assert(initproc != PROC_NULL);
4831 }
4832
4833 thread_clear_exec_promotion(old_thread);
4834 proc_rele(old_proc);
4835
4836 if (reparent_traced_child) {
4837 proc_t pp = proc_parent(old_proc);
4838 assert(pp != PROC_NULL);
4839
4840 proc_reparentlocked(new_proc, pp, 1, 0);
4841 proc_rele(pp);
4842
4843 proc_lock(new_proc);
4844 new_proc->p_lflag &= ~P_LTRACE_WAIT;
4845 proc_unlock(new_proc);
4846 }
4847
4848 return new_proc;
4849 }
4850
4851 /*
4852 * execve
4853 *
4854 * Parameters: uap->fname File name to exec
4855 * uap->argp Argument list
4856 * uap->envp Environment list
4857 *
4858 * Returns: 0 Success
4859 * __mac_execve:EINVAL Invalid argument
4860 * __mac_execve:ENOTSUP Invalid argument
4861 * __mac_execve:EACCES Permission denied
4862 * __mac_execve:EINTR Interrupted function
4863 * __mac_execve:ENOMEM Not enough space
4864 * __mac_execve:EFAULT Bad address
4865 * __mac_execve:ENAMETOOLONG Filename too long
4866 * __mac_execve:ENOEXEC Executable file format error
4867 * __mac_execve:ETXTBSY Text file busy [misuse of error code]
4868 * __mac_execve:???
4869 *
4870 * TODO: Dynamic linker header address on stack is copied via suword()
4871 */
4872 /* ARGSUSED */
4873 int
execve(proc_t p,struct execve_args * uap,int32_t * retval)4874 execve(proc_t p, struct execve_args *uap, int32_t *retval)
4875 {
4876 struct __mac_execve_args muap;
4877 int err;
4878
4879 memoryshot(VM_EXECVE, DBG_FUNC_NONE);
4880
4881 muap.fname = uap->fname;
4882 muap.argp = uap->argp;
4883 muap.envp = uap->envp;
4884 muap.mac_p = USER_ADDR_NULL;
4885 err = __mac_execve(p, &muap, retval);
4886
4887 return err;
4888 }
4889
4890 /*
4891 * __mac_execve
4892 *
4893 * Parameters: uap->fname File name to exec
4894 * uap->argp Argument list
4895 * uap->envp Environment list
4896 * uap->mac_p MAC label supplied by caller
4897 *
4898 * Returns: 0 Success
4899 * EINVAL Invalid argument
4900 * ENOTSUP Not supported
4901 * ENOEXEC Executable file format error
4902 * exec_activate_image:EINVAL Invalid argument
4903 * exec_activate_image:EACCES Permission denied
4904 * exec_activate_image:EINTR Interrupted function
4905 * exec_activate_image:ENOMEM Not enough space
4906 * exec_activate_image:EFAULT Bad address
4907 * exec_activate_image:ENAMETOOLONG Filename too long
4908 * exec_activate_image:ENOEXEC Executable file format error
4909 * exec_activate_image:ETXTBSY Text file busy [misuse of error code]
4910 * exec_activate_image:EBADEXEC The executable is corrupt/unknown
4911 * exec_activate_image:???
4912 * mac_execve_enter:???
4913 *
4914 * TODO: Dynamic linker header address on stack is copied via suword()
4915 */
4916 int
__mac_execve(proc_t p,struct __mac_execve_args * uap,int32_t * retval __unused)4917 __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval __unused)
4918 {
4919 struct image_params *imgp = NULL;
4920 struct vnode_attr *vap = NULL;
4921 struct vnode_attr *origvap = NULL;
4922 int error;
4923 int is_64 = IS_64BIT_PROCESS(p);
4924 struct vfs_context context;
4925 struct uthread *uthread = NULL;
4926 task_t old_task = current_task();
4927 task_t new_task = NULL;
4928 boolean_t should_release_proc_ref = FALSE;
4929 boolean_t exec_done = FALSE;
4930 void *inherit = NULL;
4931 struct {
4932 struct image_params imgp;
4933 struct vnode_attr va;
4934 struct vnode_attr origva;
4935 } *__execve_data;
4936
4937 /* Allocate a big chunk for locals instead of using stack since these
4938 * structures a pretty big.
4939 */
4940 __execve_data = kalloc_type(typeof(*__execve_data), Z_WAITOK | Z_ZERO);
4941 if (__execve_data == NULL) {
4942 error = ENOMEM;
4943 goto exit_with_error;
4944 }
4945 imgp = &__execve_data->imgp;
4946 vap = &__execve_data->va;
4947 origvap = &__execve_data->origva;
4948
4949 /* Initialize the common data in the image_params structure */
4950 imgp->ip_user_fname = uap->fname;
4951 imgp->ip_user_argv = uap->argp;
4952 imgp->ip_user_envv = uap->envp;
4953 imgp->ip_vattr = vap;
4954 imgp->ip_origvattr = origvap;
4955 imgp->ip_vfs_context = &context;
4956 imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE) | ((p->p_flag & P_DISABLE_ASLR) ? IMGPF_DISABLE_ASLR : IMGPF_NONE);
4957 imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
4958 imgp->ip_mac_return = 0;
4959 imgp->ip_cs_error = OS_REASON_NULL;
4960 imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
4961 imgp->ip_subsystem_root_path = NULL;
4962 uthread_set_exec_data(current_uthread(), imgp);
4963
4964 #if CONFIG_MACF
4965 if (uap->mac_p != USER_ADDR_NULL) {
4966 error = mac_execve_enter(uap->mac_p, imgp);
4967 if (error) {
4968 goto exit_with_error;
4969 }
4970 }
4971 #endif
4972 uthread = current_uthread();
4973 {
4974 imgp->ip_flags |= IMGPF_EXEC;
4975
4976 /* Adjust the user proc count */
4977 (void)chgproccnt(kauth_getruid(), 1);
4978 /*
4979 * For execve case, create a new proc, task and thread
4980 * but don't make the proc visible to userland. After
4981 * image activation, the new proc would take place of
4982 * the old proc in pid hash and other lists that make
4983 * the proc visible to the system.
4984 */
4985 imgp->ip_new_thread = cloneproc(old_task, NULL, p, CLONEPROC_FLAGS_FOR_EXEC);
4986 /* task and thread ref returned by cloneproc */
4987 if (imgp->ip_new_thread == NULL) {
4988 (void)chgproccnt(kauth_getruid(), -1);
4989 error = ENOMEM;
4990 goto exit_with_error;
4991 }
4992
4993 new_task = get_threadtask(imgp->ip_new_thread);
4994 }
4995
4996 p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
4997
4998 context.vc_thread = imgp->ip_new_thread;
4999 context.vc_ucred = kauth_cred_proc_ref(p); /* XXX must NOT be kauth_cred_get() */
5000
5001 imgp->ip_subsystem_root_path = p->p_subsystem_root_path;
5002
5003 proc_transend(p, 0);
5004 proc_signalend(p, 0);
5005
5006 /*
5007 * Activate the image.
5008 * Warning: If activation failed after point of no return, it returns error
5009 * as 0 and pretends the call succeeded.
5010 */
5011 error = exec_activate_image(imgp);
5012 /* thread and task ref returned for vfexec case */
5013
5014 if (imgp->ip_new_thread != NULL) {
5015 /*
5016 * task reference might be returned by exec_activate_image
5017 * for vfexec.
5018 */
5019 new_task = get_threadtask(imgp->ip_new_thread);
5020 #if defined(HAS_APPLE_PAC)
5021 ml_task_set_disable_user_jop(new_task, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
5022 ml_thread_set_disable_user_jop(imgp->ip_new_thread, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
5023 #endif
5024 }
5025
5026 if (!error) {
5027 p = proc_exec_switch_task(current_proc(), p, old_task, new_task, imgp->ip_new_thread, &inherit);
5028 /* proc ref returned */
5029 should_release_proc_ref = TRUE;
5030 }
5031
5032 kauth_cred_unref(&context.vc_ucred);
5033
5034 if (!error) {
5035 exec_done = TRUE;
5036 assert(imgp->ip_new_thread != NULL);
5037 /*
5038 * Enable new task IPC access if exec_activate_image() returned an
5039 * active task. (Checks active bit in ipc_task_enable() under lock).
5040 */
5041 ipc_task_enable(new_task);
5042
5043 exec_resettextvp(p, imgp);
5044 error = process_signature(p, imgp);
5045 }
5046
5047 #if defined(HAS_APPLE_PAC)
5048 if (imgp->ip_new_thread && !error) {
5049 ml_task_set_jop_pid_from_shared_region(new_task);
5050 ml_thread_set_jop_pid(imgp->ip_new_thread, new_task);
5051 }
5052 #endif /* defined(HAS_APPLE_PAC) */
5053
5054 /* flag exec has occurred, notify only if it has not failed due to FP Key error */
5055 if (exec_done && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
5056 proc_knote(p, NOTE_EXEC);
5057 }
5058
5059 if (imgp->ip_vp != NULLVP) {
5060 vnode_put(imgp->ip_vp);
5061 }
5062 if (imgp->ip_scriptvp != NULLVP) {
5063 vnode_put(imgp->ip_scriptvp);
5064 }
5065 if (imgp->ip_strings) {
5066 execargs_free(imgp);
5067 }
5068 #if CONFIG_MACF
5069 if (imgp->ip_execlabelp) {
5070 mac_cred_label_free(imgp->ip_execlabelp);
5071 imgp->ip_execlabelp = NULL;
5072 }
5073 if (imgp->ip_scriptlabelp) {
5074 mac_vnode_label_free(imgp->ip_scriptlabelp);
5075 imgp->ip_scriptlabelp = NULL;
5076 }
5077 #endif
5078 if (imgp->ip_cs_error != OS_REASON_NULL) {
5079 os_reason_free(imgp->ip_cs_error);
5080 imgp->ip_cs_error = OS_REASON_NULL;
5081 }
5082
5083 if (!error) {
5084 /*
5085 * We need to initialize the bank context behind the protection of
5086 * the proc_trans lock to prevent a race with exit. We can't do this during
5087 * exec_activate_image because task_bank_init checks entitlements that
5088 * aren't loaded until subsequent calls (including exec_resettextvp).
5089 */
5090 error = proc_transstart(p, 0, 0);
5091 }
5092
5093 if (!error) {
5094 task_bank_init(new_task);
5095 proc_transend(p, 0);
5096
5097 // Don't inherit crash behavior across exec
5098 p->p_crash_behavior = 0;
5099 p->p_crash_behavior_deadline = 0;
5100
5101 #if __arm64__
5102 proc_footprint_entitlement_hacks(p, new_task);
5103 #endif /* __arm64__ */
5104
5105 #if XNU_TARGET_OS_OSX
5106 if (IOTaskHasEntitlement(new_task, SINGLE_JIT_ENTITLEMENT)) {
5107 vm_map_single_jit(get_task_map(new_task));
5108 }
5109 #endif /* XNU_TARGET_OS_OSX */
5110
5111 /* Sever any extant thread affinity */
5112 thread_affinity_exec(current_thread());
5113
5114 /* Inherit task role from old task to new task for exec */
5115 proc_inherit_task_role(new_task, old_task);
5116
5117 thread_t main_thread = imgp->ip_new_thread;
5118
5119 task_set_main_thread_qos(new_task, main_thread);
5120
5121 #if __has_feature(ptrauth_calls)
5122 task_set_pac_exception_fatal_flag(new_task);
5123 #endif /* __has_feature(ptrauth_calls) */
5124
5125 #if CONFIG_ARCADE
5126 /*
5127 * Check to see if we need to trigger an arcade upcall AST now
5128 * that the vnode has been reset on the task.
5129 */
5130 arcade_prepare(new_task, imgp->ip_new_thread);
5131 #endif /* CONFIG_ARCADE */
5132
5133 #if CONFIG_MACF
5134 proc_apply_jit_and_jumbo_va_policies(p, new_task);
5135 #endif /* CONFIG_MACF */
5136 proc_apply_tpro(imgp, new_task);
5137
5138 #if CONFIG_MAP_RANGES
5139 proc_apply_vm_range_policies(p, new_task);
5140 #endif /* CONFIG_MAP_RANGES */
5141
5142 if (vm_darkwake_mode == TRUE) {
5143 /*
5144 * This process is being launched when the system
5145 * is in darkwake. So mark it specially. This will
5146 * cause all its pages to be entered in the background Q.
5147 */
5148 task_set_darkwake_mode(new_task, vm_darkwake_mode);
5149 }
5150
5151 #if CONFIG_DTRACE
5152 dtrace_thread_didexec(imgp->ip_new_thread);
5153
5154 if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
5155 (*dtrace_proc_waitfor_hook)(p);
5156 }
5157 #endif
5158
5159 #if CONFIG_AUDIT
5160 if (!error && AUDIT_ENABLED() && p) {
5161 /* Add the CDHash of the new process to the audit record */
5162 uint8_t *cdhash = cs_get_cdhash(p);
5163 if (cdhash) {
5164 AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
5165 }
5166 }
5167 #endif
5168 } else {
5169 DTRACE_PROC1(exec__failure, int, error);
5170 }
5171
5172 exit_with_error:
5173
5174 /* terminate the new task it if exec failed */
5175 if (new_task != NULL && task_is_exec_copy(new_task)) {
5176 task_terminate_internal(new_task);
5177 }
5178
5179 if (imgp != NULL) {
5180 /* Clear the initial wait on the thread transferring watchports */
5181 if (imgp->ip_new_thread) {
5182 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
5183 }
5184
5185 /* Transfer the watchport boost to new task */
5186 if (!error) {
5187 task_transfer_turnstile_watchports(old_task,
5188 new_task, imgp->ip_new_thread);
5189 }
5190 /*
5191 * Do not terminate the current task, if proc_exec_switch_task did not
5192 * switch the tasks, terminating the current task without the switch would
5193 * result in loosing the SIGKILL status.
5194 */
5195 if (task_did_exec(old_task)) {
5196 /* Terminate the current task, since exec will start in new task */
5197 task_terminate_internal(old_task);
5198 }
5199
5200 /* Release the thread ref returned by cloneproc */
5201 if (imgp->ip_new_thread) {
5202 /* wake up the new exec thread */
5203 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
5204 thread_deallocate(imgp->ip_new_thread);
5205 imgp->ip_new_thread = NULL;
5206 }
5207 }
5208
5209 /* Release the ref returned by fork_create_child */
5210 if (new_task) {
5211 task_deallocate(new_task);
5212 new_task = NULL;
5213 }
5214
5215 if (should_release_proc_ref) {
5216 proc_rele(p);
5217 }
5218
5219 uthread_set_exec_data(current_uthread(), NULL);
5220 kfree_type(typeof(*__execve_data), __execve_data);
5221
5222 if (inherit != NULL) {
5223 ipc_importance_release(inherit);
5224 }
5225
5226 return error;
5227 }
5228
5229
5230 /*
5231 * copyinptr
5232 *
5233 * Description: Copy a pointer in from user space to a user_addr_t in kernel
5234 * space, based on 32/64 bitness of the user space
5235 *
5236 * Parameters: froma User space address
5237 * toptr Address of kernel space user_addr_t
5238 * ptr_size 4/8, based on 'froma' address space
5239 *
5240 * Returns: 0 Success
5241 * EFAULT Bad 'froma'
5242 *
5243 * Implicit returns:
5244 * *ptr_size Modified
5245 */
5246 static int
copyinptr(user_addr_t froma,user_addr_t * toptr,int ptr_size)5247 copyinptr(user_addr_t froma, user_addr_t *toptr, int ptr_size)
5248 {
5249 int error;
5250
5251 if (ptr_size == 4) {
5252 /* 64 bit value containing 32 bit address */
5253 unsigned int i = 0;
5254
5255 error = copyin(froma, &i, 4);
5256 *toptr = CAST_USER_ADDR_T(i); /* SAFE */
5257 } else {
5258 error = copyin(froma, toptr, 8);
5259 }
5260 return error;
5261 }
5262
5263
5264 /*
5265 * copyoutptr
5266 *
5267 * Description: Copy a pointer out from a user_addr_t in kernel space to
5268 * user space, based on 32/64 bitness of the user space
5269 *
5270 * Parameters: ua User space address to copy to
5271 * ptr Address of kernel space user_addr_t
5272 * ptr_size 4/8, based on 'ua' address space
5273 *
5274 * Returns: 0 Success
5275 * EFAULT Bad 'ua'
5276 *
5277 */
5278 static int
copyoutptr(user_addr_t ua,user_addr_t ptr,int ptr_size)5279 copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size)
5280 {
5281 int error;
5282
5283 if (ptr_size == 4) {
5284 /* 64 bit value containing 32 bit address */
5285 unsigned int i = CAST_DOWN_EXPLICIT(unsigned int, ua); /* SAFE */
5286
5287 error = copyout(&i, ptr, 4);
5288 } else {
5289 error = copyout(&ua, ptr, 8);
5290 }
5291 return error;
5292 }
5293
5294
5295 /*
5296 * exec_copyout_strings
5297 *
5298 * Copy out the strings segment to user space. The strings segment is put
5299 * on a preinitialized stack frame.
5300 *
5301 * Parameters: struct image_params * the image parameter block
5302 * int * a pointer to the stack offset variable
5303 *
5304 * Returns: 0 Success
5305 * !0 Faiure: errno
5306 *
5307 * Implicit returns:
5308 * (*stackp) The stack offset, modified
5309 *
5310 * Note: The strings segment layout is backward, from the beginning
5311 * of the top of the stack to consume the minimal amount of
5312 * space possible; the returned stack pointer points to the
5313 * end of the area consumed (stacks grow downward).
5314 *
5315 * argc is an int; arg[i] are pointers; env[i] are pointers;
5316 * the 0's are (void *)NULL's
5317 *
5318 * The stack frame layout is:
5319 *
5320 * +-------------+ <- p->user_stack
5321 * | 16b |
5322 * +-------------+
5323 * | STRING AREA |
5324 * | : |
5325 * | : |
5326 * | : |
5327 * +- -- -- -- --+
5328 * | PATH AREA |
5329 * +-------------+
5330 * | 0 |
5331 * +-------------+
5332 * | applev[n] |
5333 * +-------------+
5334 * :
5335 * :
5336 * +-------------+
5337 * | applev[1] |
5338 * +-------------+
5339 * | exec_path / |
5340 * | applev[0] |
5341 * +-------------+
5342 * | 0 |
5343 * +-------------+
5344 * | env[n] |
5345 * +-------------+
5346 * :
5347 * :
5348 * +-------------+
5349 * | env[0] |
5350 * +-------------+
5351 * | 0 |
5352 * +-------------+
5353 * | arg[argc-1] |
5354 * +-------------+
5355 * :
5356 * :
5357 * +-------------+
5358 * | arg[0] |
5359 * +-------------+
5360 * | argc |
5361 * sp-> +-------------+
5362 *
5363 * Although technically a part of the STRING AREA, we treat the PATH AREA as
5364 * a separate entity. This allows us to align the beginning of the PATH AREA
5365 * to a pointer boundary so that the exec_path, env[i], and argv[i] pointers
5366 * which preceed it on the stack are properly aligned.
5367 */
5368 __attribute__((noinline))
5369 static int
exec_copyout_strings(struct image_params * imgp,user_addr_t * stackp)5370 exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp)
5371 {
5372 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
5373 int ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
5374 int ptr_area_size;
5375 void *ptr_buffer_start, *ptr_buffer;
5376 size_t string_size;
5377
5378 user_addr_t string_area; /* *argv[], *env[] */
5379 user_addr_t ptr_area; /* argv[], env[], applev[] */
5380 user_addr_t argc_area; /* argc */
5381 user_addr_t stack;
5382 int error;
5383
5384 unsigned i;
5385 struct copyout_desc {
5386 char *start_string;
5387 int count;
5388 #if CONFIG_DTRACE
5389 user_addr_t *dtrace_cookie;
5390 #endif
5391 boolean_t null_term;
5392 } descriptors[] = {
5393 {
5394 .start_string = imgp->ip_startargv,
5395 .count = imgp->ip_argc,
5396 #if CONFIG_DTRACE
5397 .dtrace_cookie = &p->p_dtrace_argv,
5398 #endif
5399 .null_term = TRUE
5400 },
5401 {
5402 .start_string = imgp->ip_endargv,
5403 .count = imgp->ip_envc,
5404 #if CONFIG_DTRACE
5405 .dtrace_cookie = &p->p_dtrace_envp,
5406 #endif
5407 .null_term = TRUE
5408 },
5409 {
5410 .start_string = imgp->ip_strings,
5411 .count = 1,
5412 #if CONFIG_DTRACE
5413 .dtrace_cookie = NULL,
5414 #endif
5415 .null_term = FALSE
5416 },
5417 {
5418 .start_string = imgp->ip_endenvv,
5419 .count = imgp->ip_applec - 1, /* exec_path handled above */
5420 #if CONFIG_DTRACE
5421 .dtrace_cookie = NULL,
5422 #endif
5423 .null_term = TRUE
5424 }
5425 };
5426
5427 stack = *stackp;
5428
5429 /*
5430 * All previous contributors to the string area
5431 * should have aligned their sub-area
5432 */
5433 if (imgp->ip_strspace % ptr_size != 0) {
5434 error = EINVAL;
5435 goto bad;
5436 }
5437
5438 /* Grow the stack down for the strings we've been building up */
5439 string_size = imgp->ip_strendp - imgp->ip_strings;
5440 stack -= string_size;
5441 string_area = stack;
5442
5443 /*
5444 * Need room for one pointer for each string, plus
5445 * one for the NULLs terminating the argv, envv, and apple areas.
5446 */
5447 ptr_area_size = (imgp->ip_argc + imgp->ip_envc + imgp->ip_applec + 3) * ptr_size;
5448 stack -= ptr_area_size;
5449 ptr_area = stack;
5450
5451 /* We'll construct all the pointer arrays in our string buffer,
5452 * which we already know is aligned properly, and ip_argspace
5453 * was used to verify we have enough space.
5454 */
5455 ptr_buffer_start = ptr_buffer = (void *)imgp->ip_strendp;
5456
5457 /*
5458 * Need room for pointer-aligned argc slot.
5459 */
5460 stack -= ptr_size;
5461 argc_area = stack;
5462
5463 /*
5464 * Record the size of the arguments area so that sysctl_procargs()
5465 * can return the argument area without having to parse the arguments.
5466 */
5467 proc_lock(p);
5468 p->p_argc = imgp->ip_argc;
5469 p->p_argslen = (int)(*stackp - string_area);
5470 proc_unlock(p);
5471
5472 /* Return the initial stack address: the location of argc */
5473 *stackp = stack;
5474
5475 /*
5476 * Copy out the entire strings area.
5477 */
5478 error = copyout(imgp->ip_strings, string_area,
5479 string_size);
5480 if (error) {
5481 goto bad;
5482 }
5483
5484 for (i = 0; i < sizeof(descriptors) / sizeof(descriptors[0]); i++) {
5485 char *cur_string = descriptors[i].start_string;
5486 int j;
5487
5488 #if CONFIG_DTRACE
5489 if (descriptors[i].dtrace_cookie) {
5490 proc_lock(p);
5491 *descriptors[i].dtrace_cookie = ptr_area + ((uintptr_t)ptr_buffer - (uintptr_t)ptr_buffer_start); /* dtrace convenience */
5492 proc_unlock(p);
5493 }
5494 #endif /* CONFIG_DTRACE */
5495
5496 /*
5497 * For each segment (argv, envv, applev), copy as many pointers as requested
5498 * to our pointer buffer.
5499 */
5500 for (j = 0; j < descriptors[i].count; j++) {
5501 user_addr_t cur_address = string_area + (cur_string - imgp->ip_strings);
5502
5503 /* Copy out the pointer to the current string. Alignment has been verified */
5504 if (ptr_size == 8) {
5505 *(uint64_t *)ptr_buffer = (uint64_t)cur_address;
5506 } else {
5507 *(uint32_t *)ptr_buffer = (uint32_t)cur_address;
5508 }
5509
5510 ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
5511 cur_string += strlen(cur_string) + 1; /* Only a NUL between strings in the same area */
5512 }
5513
5514 if (descriptors[i].null_term) {
5515 if (ptr_size == 8) {
5516 *(uint64_t *)ptr_buffer = 0ULL;
5517 } else {
5518 *(uint32_t *)ptr_buffer = 0;
5519 }
5520
5521 ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
5522 }
5523 }
5524
5525 /*
5526 * Copy out all our pointer arrays in bulk.
5527 */
5528 error = copyout(ptr_buffer_start, ptr_area,
5529 ptr_area_size);
5530 if (error) {
5531 goto bad;
5532 }
5533
5534 /* argc (int32, stored in a ptr_size area) */
5535 error = copyoutptr((user_addr_t)imgp->ip_argc, argc_area, ptr_size);
5536 if (error) {
5537 goto bad;
5538 }
5539
5540 bad:
5541 return error;
5542 }
5543
5544
5545 /*
5546 * exec_extract_strings
5547 *
5548 * Copy arguments and environment from user space into work area; we may
5549 * have already copied some early arguments into the work area, and if
5550 * so, any arguments opied in are appended to those already there.
5551 * This function is the primary manipulator of ip_argspace, since
5552 * these are the arguments the client of execve(2) knows about. After
5553 * each argv[]/envv[] string is copied, we charge the string length
5554 * and argv[]/envv[] pointer slot to ip_argspace, so that we can
5555 * full preflight the arg list size.
5556 *
5557 * Parameters: struct image_params * the image parameter block
5558 *
5559 * Returns: 0 Success
5560 * !0 Failure: errno
5561 *
5562 * Implicit returns;
5563 * (imgp->ip_argc) Count of arguments, updated
5564 * (imgp->ip_envc) Count of environment strings, updated
5565 * (imgp->ip_argspace) Count of remaining of NCARGS
5566 * (imgp->ip_interp_buffer) Interpreter and args (mutated in place)
5567 *
5568 *
5569 * Note: The argument and environment vectors are user space pointers
5570 * to arrays of user space pointers.
5571 */
5572 __attribute__((noinline))
5573 static int
exec_extract_strings(struct image_params * imgp)5574 exec_extract_strings(struct image_params *imgp)
5575 {
5576 int error = 0;
5577 int ptr_size = (imgp->ip_flags & IMGPF_WAS_64BIT_ADDR) ? 8 : 4;
5578 int new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
5579 user_addr_t argv = imgp->ip_user_argv;
5580 user_addr_t envv = imgp->ip_user_envv;
5581
5582 /*
5583 * Adjust space reserved for the path name by however much padding it
5584 * needs. Doing this here since we didn't know if this would be a 32-
5585 * or 64-bit process back in exec_save_path.
5586 */
5587 while (imgp->ip_strspace % new_ptr_size != 0) {
5588 *imgp->ip_strendp++ = '\0';
5589 imgp->ip_strspace--;
5590 /* imgp->ip_argspace--; not counted towards exec args total */
5591 }
5592
5593 /*
5594 * From now on, we start attributing string space to ip_argspace
5595 */
5596 imgp->ip_startargv = imgp->ip_strendp;
5597 imgp->ip_argc = 0;
5598
5599 if ((imgp->ip_flags & IMGPF_INTERPRET) != 0) {
5600 user_addr_t arg;
5601 char *argstart, *ch;
5602
5603 /* First, the arguments in the "#!" string are tokenized and extracted. */
5604 argstart = imgp->ip_interp_buffer;
5605 while (argstart) {
5606 ch = argstart;
5607 while (*ch && !IS_WHITESPACE(*ch)) {
5608 ch++;
5609 }
5610
5611 if (*ch == '\0') {
5612 /* last argument, no need to NUL-terminate */
5613 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
5614 argstart = NULL;
5615 } else {
5616 /* NUL-terminate */
5617 *ch = '\0';
5618 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
5619
5620 /*
5621 * Find the next string. We know spaces at the end of the string have already
5622 * been stripped.
5623 */
5624 argstart = ch + 1;
5625 while (IS_WHITESPACE(*argstart)) {
5626 argstart++;
5627 }
5628 }
5629
5630 /* Error-check, regardless of whether this is the last interpreter arg or not */
5631 if (error) {
5632 goto bad;
5633 }
5634 if (imgp->ip_argspace < new_ptr_size) {
5635 error = E2BIG;
5636 goto bad;
5637 }
5638 imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
5639 imgp->ip_argc++;
5640 }
5641
5642 if (argv != 0LL) {
5643 /*
5644 * If we are running an interpreter, replace the av[0] that was
5645 * passed to execve() with the path name that was
5646 * passed to execve() for interpreters which do not use the PATH
5647 * to locate their script arguments.
5648 */
5649 error = copyinptr(argv, &arg, ptr_size);
5650 if (error) {
5651 goto bad;
5652 }
5653 if (arg != 0LL) {
5654 argv += ptr_size; /* consume without using */
5655 }
5656 }
5657
5658 if (imgp->ip_interp_sugid_fd != -1) {
5659 char temp[19]; /* "/dev/fd/" + 10 digits + NUL */
5660 snprintf(temp, sizeof(temp), "/dev/fd/%d", imgp->ip_interp_sugid_fd);
5661 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(temp), UIO_SYSSPACE, TRUE);
5662 } else {
5663 error = exec_add_user_string(imgp, imgp->ip_user_fname, imgp->ip_seg, TRUE);
5664 }
5665
5666 if (error) {
5667 goto bad;
5668 }
5669 if (imgp->ip_argspace < new_ptr_size) {
5670 error = E2BIG;
5671 goto bad;
5672 }
5673 imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
5674 imgp->ip_argc++;
5675 }
5676
5677 while (argv != 0LL) {
5678 user_addr_t arg;
5679
5680 error = copyinptr(argv, &arg, ptr_size);
5681 if (error) {
5682 goto bad;
5683 }
5684
5685 if (arg == 0LL) {
5686 break;
5687 }
5688
5689 argv += ptr_size;
5690
5691 /*
5692 * av[n...] = arg[n]
5693 */
5694 error = exec_add_user_string(imgp, arg, imgp->ip_seg, TRUE);
5695 if (error) {
5696 goto bad;
5697 }
5698 if (imgp->ip_argspace < new_ptr_size) {
5699 error = E2BIG;
5700 goto bad;
5701 }
5702 imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
5703 imgp->ip_argc++;
5704 }
5705
5706 /* Save space for argv[] NULL terminator */
5707 if (imgp->ip_argspace < new_ptr_size) {
5708 error = E2BIG;
5709 goto bad;
5710 }
5711 imgp->ip_argspace -= new_ptr_size;
5712
5713 /* Note where the args ends and env begins. */
5714 imgp->ip_endargv = imgp->ip_strendp;
5715 imgp->ip_envc = 0;
5716
5717 /* Now, get the environment */
5718 while (envv != 0LL) {
5719 user_addr_t env;
5720
5721 error = copyinptr(envv, &env, ptr_size);
5722 if (error) {
5723 goto bad;
5724 }
5725
5726 envv += ptr_size;
5727 if (env == 0LL) {
5728 break;
5729 }
5730 /*
5731 * av[n...] = env[n]
5732 */
5733 error = exec_add_user_string(imgp, env, imgp->ip_seg, TRUE);
5734 if (error) {
5735 goto bad;
5736 }
5737 if (imgp->ip_argspace < new_ptr_size) {
5738 error = E2BIG;
5739 goto bad;
5740 }
5741 imgp->ip_argspace -= new_ptr_size; /* to hold envv[] entry */
5742 imgp->ip_envc++;
5743 }
5744
5745 /* Save space for envv[] NULL terminator */
5746 if (imgp->ip_argspace < new_ptr_size) {
5747 error = E2BIG;
5748 goto bad;
5749 }
5750 imgp->ip_argspace -= new_ptr_size;
5751
5752 /* Align the tail of the combined argv+envv area */
5753 while (imgp->ip_strspace % new_ptr_size != 0) {
5754 if (imgp->ip_argspace < 1) {
5755 error = E2BIG;
5756 goto bad;
5757 }
5758 *imgp->ip_strendp++ = '\0';
5759 imgp->ip_strspace--;
5760 imgp->ip_argspace--;
5761 }
5762
5763 /* Note where the envv ends and applev begins. */
5764 imgp->ip_endenvv = imgp->ip_strendp;
5765
5766 /*
5767 * From now on, we are no longer charging argument
5768 * space to ip_argspace.
5769 */
5770
5771 bad:
5772 return error;
5773 }
5774
5775 /*
5776 * Libc has an 8-element array set up for stack guard values. It only fills
5777 * in one of those entries, and both gcc and llvm seem to use only a single
5778 * 8-byte guard. Until somebody needs more than an 8-byte guard value, don't
5779 * do the work to construct them.
5780 */
5781 #define GUARD_VALUES 1
5782 #define GUARD_KEY "stack_guard="
5783
5784 /*
5785 * System malloc needs some entropy when it is initialized.
5786 */
5787 #define ENTROPY_VALUES 2
5788 #define ENTROPY_KEY "malloc_entropy="
5789
5790 /*
5791 * libplatform needs a random pointer-obfuscation value when it is initialized.
5792 */
5793 #define PTR_MUNGE_VALUES 1
5794 #define PTR_MUNGE_KEY "ptr_munge="
5795
5796 /*
5797 * System malloc engages nanozone for UIAPP.
5798 */
5799 #define NANO_ENGAGE_KEY "MallocNanoZone=1"
5800
5801 /*
5802 * System malloc uses deferred reclaim
5803 * for UIAPP on embedded systems with swap.
5804 */
5805 #define RECLAIM_ENGAGE_KEY "MallocDeferredReclaim=1"
5806 /*
5807 * Used to pass experiment flags up to libmalloc.
5808 */
5809 #define LIBMALLOC_EXPERIMENT_FACTORS_KEY "MallocExperiment="
5810
5811 #define PFZ_KEY "pfz="
5812 extern user32_addr_t commpage_text32_location;
5813 extern user64_addr_t commpage_text64_location;
5814
5815 extern uuid_string_t bootsessionuuid_string;
5816
5817 #define MAIN_STACK_VALUES 4
5818 #define MAIN_STACK_KEY "main_stack="
5819
5820 #define FSID_KEY "executable_file="
5821 #define DYLD_FSID_KEY "dyld_file="
5822 #define CDHASH_KEY "executable_cdhash="
5823 #define DYLD_FLAGS_KEY "dyld_flags="
5824 #define SUBSYSTEM_ROOT_PATH_KEY "subsystem_root_path="
5825 #define APP_BOOT_SESSION_KEY "executable_boothash="
5826 #if __has_feature(ptrauth_calls)
5827 #define PTRAUTH_DISABLED_FLAG "ptrauth_disabled=1"
5828 #define DYLD_ARM64E_ABI_KEY "arm64e_abi="
5829 #endif /* __has_feature(ptrauth_calls) */
5830 #define MAIN_TH_PORT_KEY "th_port="
5831
5832 #define FSID_MAX_STRING "0x1234567890abcdef,0x1234567890abcdef"
5833
5834 #define HEX_STR_LEN 18 // 64-bit hex value "0x0123456701234567"
5835 #define HEX_STR_LEN32 10 // 32-bit hex value "0x01234567"
5836
5837 #if XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES
5838 #define VM_FORCE_4K_PAGES_KEY "vm_force_4k_pages=1"
5839 #endif /* XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES */
5840
5841 static int
exec_add_entropy_key(struct image_params * imgp,const char * key,int values,boolean_t embedNUL)5842 exec_add_entropy_key(struct image_params *imgp,
5843 const char *key,
5844 int values,
5845 boolean_t embedNUL)
5846 {
5847 const int limit = 8;
5848 uint64_t entropy[limit];
5849 char str[strlen(key) + (HEX_STR_LEN + 1) * limit + 1];
5850 if (values > limit) {
5851 values = limit;
5852 }
5853
5854 read_random(entropy, sizeof(entropy[0]) * values);
5855
5856 if (embedNUL) {
5857 entropy[0] &= ~(0xffull << 8);
5858 }
5859
5860 int len = scnprintf(str, sizeof(str), "%s0x%llx", key, entropy[0]);
5861 size_t remaining = sizeof(str) - len;
5862 for (int i = 1; i < values && remaining > 0; ++i) {
5863 size_t start = sizeof(str) - remaining;
5864 len = scnprintf(&str[start], remaining, ",0x%llx", entropy[i]);
5865 remaining -= len;
5866 }
5867
5868 return exec_add_user_string(imgp, CAST_USER_ADDR_T(str), UIO_SYSSPACE, FALSE);
5869 }
5870
5871 /*
5872 * Build up the contents of the apple[] string vector
5873 */
5874 #if (DEVELOPMENT || DEBUG)
5875 extern uint64_t dyld_flags;
5876 #endif
5877
5878 #if __has_feature(ptrauth_calls)
5879 static inline bool
is_arm64e_running_as_arm64(const struct image_params * imgp)5880 is_arm64e_running_as_arm64(const struct image_params *imgp)
5881 {
5882 return (imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
5883 (imgp->ip_flags & IMGPF_NOJOP);
5884 }
5885 #endif /* __has_feature(ptrauth_calls) */
5886
5887 _Atomic uint64_t libmalloc_experiment_factors = 0;
5888
5889 static int
exec_add_apple_strings(struct image_params * imgp,const load_result_t * load_result)5890 exec_add_apple_strings(struct image_params *imgp,
5891 const load_result_t *load_result)
5892 {
5893 int error;
5894 int img_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
5895 thread_t new_thread;
5896 ipc_port_t sright;
5897 uint64_t local_experiment_factors = 0;
5898
5899 /* exec_save_path stored the first string */
5900 imgp->ip_applec = 1;
5901
5902 /* adding the pfz string */
5903 {
5904 char pfz_string[strlen(PFZ_KEY) + HEX_STR_LEN + 1];
5905
5906 if (img_ptr_size == 8) {
5907 __assert_only size_t ret = snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%llx", commpage_text64_location);
5908 assert(ret < sizeof(pfz_string));
5909 } else {
5910 snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%x", commpage_text32_location);
5911 }
5912 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(pfz_string), UIO_SYSSPACE, FALSE);
5913 if (error) {
5914 printf("Failed to add the pfz string with error %d\n", error);
5915 goto bad;
5916 }
5917 imgp->ip_applec++;
5918 }
5919
5920 /* adding the NANO_ENGAGE_KEY key */
5921 if (imgp->ip_px_sa) {
5922 struct _posix_spawnattr* psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
5923 int proc_flags = psa->psa_flags;
5924
5925 if ((proc_flags & _POSIX_SPAWN_NANO_ALLOCATOR) == _POSIX_SPAWN_NANO_ALLOCATOR) {
5926 const char *nano_string = NANO_ENGAGE_KEY;
5927 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(nano_string), UIO_SYSSPACE, FALSE);
5928 if (error) {
5929 goto bad;
5930 }
5931 imgp->ip_applec++;
5932 }
5933 #if CONFIG_JETSAM && CONFIG_MEMORYSTATUS && CONFIG_DEFERRED_RECLAIM
5934 if (memorystatus_swap_all_apps) {
5935 int psa_apptype = psa->psa_apptype;
5936
5937 if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) == POSIX_SPAWN_PROC_TYPE_APP_DEFAULT) {
5938 const char *reclaim_string = RECLAIM_ENGAGE_KEY;
5939 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(reclaim_string), UIO_SYSSPACE, FALSE);
5940 if (error) {
5941 goto bad;
5942 }
5943 imgp->ip_applec++;
5944 }
5945 }
5946 #endif /* CONFIG_JETSAM && CONFIG_MEMORYSTATUS && CONFIG_DEFERRED_RECLAIM */
5947 }
5948
5949 /*
5950 * Supply libc with a collection of random values to use when
5951 * implementing -fstack-protector.
5952 *
5953 * (The first random string always contains an embedded NUL so that
5954 * __stack_chk_guard also protects against C string vulnerabilities)
5955 */
5956 error = exec_add_entropy_key(imgp, GUARD_KEY, GUARD_VALUES, TRUE);
5957 if (error) {
5958 goto bad;
5959 }
5960 imgp->ip_applec++;
5961
5962 /*
5963 * Supply libc with entropy for system malloc.
5964 */
5965 error = exec_add_entropy_key(imgp, ENTROPY_KEY, ENTROPY_VALUES, FALSE);
5966 if (error) {
5967 goto bad;
5968 }
5969 imgp->ip_applec++;
5970
5971 /*
5972 * Supply libpthread & libplatform with a random value to use for pointer
5973 * obfuscation.
5974 */
5975 error = exec_add_entropy_key(imgp, PTR_MUNGE_KEY, PTR_MUNGE_VALUES, FALSE);
5976 if (error) {
5977 goto bad;
5978 }
5979 imgp->ip_applec++;
5980
5981 /*
5982 * Add MAIN_STACK_KEY: Supplies the address and size of the main thread's
5983 * stack if it was allocated by the kernel.
5984 *
5985 * The guard page is not included in this stack size as libpthread
5986 * expects to add it back in after receiving this value.
5987 */
5988 if (load_result->unixproc) {
5989 char stack_string[strlen(MAIN_STACK_KEY) + (HEX_STR_LEN + 1) * MAIN_STACK_VALUES + 1];
5990 snprintf(stack_string, sizeof(stack_string),
5991 MAIN_STACK_KEY "0x%llx,0x%llx,0x%llx,0x%llx",
5992 (uint64_t)load_result->user_stack,
5993 (uint64_t)load_result->user_stack_size,
5994 (uint64_t)load_result->user_stack_alloc,
5995 (uint64_t)load_result->user_stack_alloc_size);
5996 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(stack_string), UIO_SYSSPACE, FALSE);
5997 if (error) {
5998 goto bad;
5999 }
6000 imgp->ip_applec++;
6001 }
6002
6003 if (imgp->ip_vattr) {
6004 uint64_t fsid = vnode_get_va_fsid(imgp->ip_vattr);
6005 uint64_t fsobjid = imgp->ip_vattr->va_fileid;
6006
6007 char fsid_string[strlen(FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
6008 snprintf(fsid_string, sizeof(fsid_string),
6009 FSID_KEY "0x%llx,0x%llx", fsid, fsobjid);
6010 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
6011 if (error) {
6012 goto bad;
6013 }
6014 imgp->ip_applec++;
6015 }
6016
6017 if (imgp->ip_dyld_fsid || imgp->ip_dyld_fsobjid) {
6018 char fsid_string[strlen(DYLD_FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
6019 snprintf(fsid_string, sizeof(fsid_string),
6020 DYLD_FSID_KEY "0x%llx,0x%llx", imgp->ip_dyld_fsid, imgp->ip_dyld_fsobjid);
6021 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
6022 if (error) {
6023 goto bad;
6024 }
6025 imgp->ip_applec++;
6026 }
6027
6028 uint8_t cdhash[SHA1_RESULTLEN];
6029 int cdhash_errror = ubc_cs_getcdhash(imgp->ip_vp, imgp->ip_arch_offset, cdhash);
6030 if (cdhash_errror == 0) {
6031 char hash_string[strlen(CDHASH_KEY) + 2 * SHA1_RESULTLEN + 1];
6032 strncpy(hash_string, CDHASH_KEY, sizeof(hash_string));
6033 char *p = hash_string + sizeof(CDHASH_KEY) - 1;
6034 for (int i = 0; i < SHA1_RESULTLEN; i++) {
6035 snprintf(p, 3, "%02x", (int) cdhash[i]);
6036 p += 2;
6037 }
6038 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(hash_string), UIO_SYSSPACE, FALSE);
6039 if (error) {
6040 goto bad;
6041 }
6042 imgp->ip_applec++;
6043
6044 /* hash together cd-hash and boot-session-uuid */
6045 uint8_t sha_digest[SHA256_DIGEST_LENGTH];
6046 SHA256_CTX sha_ctx;
6047 SHA256_Init(&sha_ctx);
6048 SHA256_Update(&sha_ctx, bootsessionuuid_string, sizeof(bootsessionuuid_string));
6049 SHA256_Update(&sha_ctx, cdhash, sizeof(cdhash));
6050 SHA256_Final(sha_digest, &sha_ctx);
6051 char app_boot_string[strlen(APP_BOOT_SESSION_KEY) + 2 * SHA1_RESULTLEN + 1];
6052 strncpy(app_boot_string, APP_BOOT_SESSION_KEY, sizeof(app_boot_string));
6053 char *s = app_boot_string + sizeof(APP_BOOT_SESSION_KEY) - 1;
6054 for (int i = 0; i < SHA1_RESULTLEN; i++) {
6055 snprintf(s, 3, "%02x", (int) sha_digest[i]);
6056 s += 2;
6057 }
6058 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(app_boot_string), UIO_SYSSPACE, FALSE);
6059 if (error) {
6060 goto bad;
6061 }
6062 imgp->ip_applec++;
6063 }
6064 #if (DEVELOPMENT || DEBUG)
6065 if (dyld_flags) {
6066 char dyld_flags_string[strlen(DYLD_FLAGS_KEY) + HEX_STR_LEN + 1];
6067 snprintf(dyld_flags_string, sizeof(dyld_flags_string), DYLD_FLAGS_KEY "0x%llx", dyld_flags);
6068 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_flags_string), UIO_SYSSPACE, FALSE);
6069 if (error) {
6070 goto bad;
6071 }
6072 imgp->ip_applec++;
6073 }
6074 #endif
6075 if (imgp->ip_subsystem_root_path) {
6076 size_t buffer_len = MAXPATHLEN + strlen(SUBSYSTEM_ROOT_PATH_KEY);
6077 char subsystem_root_path_string[buffer_len];
6078 int required_len = snprintf(subsystem_root_path_string, buffer_len, SUBSYSTEM_ROOT_PATH_KEY "%s", imgp->ip_subsystem_root_path);
6079
6080 if (((size_t)required_len >= buffer_len) || (required_len < 0)) {
6081 error = ENAMETOOLONG;
6082 goto bad;
6083 }
6084
6085 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(subsystem_root_path_string), UIO_SYSSPACE, FALSE);
6086 if (error) {
6087 goto bad;
6088 }
6089
6090 imgp->ip_applec++;
6091 }
6092 #if __has_feature(ptrauth_calls)
6093 if (is_arm64e_running_as_arm64(imgp)) {
6094 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(PTRAUTH_DISABLED_FLAG), UIO_SYSSPACE, FALSE);
6095 if (error) {
6096 goto bad;
6097 }
6098
6099 imgp->ip_applec++;
6100 }
6101 #endif /* __has_feature(ptrauth_calls) */
6102
6103
6104 #if __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX)
6105 {
6106 char dyld_abi_string[strlen(DYLD_ARM64E_ABI_KEY) + 8];
6107 strlcpy(dyld_abi_string, DYLD_ARM64E_ABI_KEY, sizeof(dyld_abi_string));
6108 bool allowAll = bootarg_arm64e_preview_abi;
6109 strlcat(dyld_abi_string, (allowAll ? "all" : "os"), sizeof(dyld_abi_string));
6110 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_abi_string), UIO_SYSSPACE, FALSE);
6111 if (error) {
6112 goto bad;
6113 }
6114
6115 imgp->ip_applec++;
6116 }
6117 #endif
6118 /*
6119 * Add main thread mach port name
6120 * +1 uref on main thread port, this ref will be extracted by libpthread in __pthread_init
6121 * and consumed in _bsdthread_terminate. Leaking the main thread port name if not linked
6122 * against libpthread.
6123 */
6124 if ((new_thread = imgp->ip_new_thread) != THREAD_NULL) {
6125 thread_reference(new_thread);
6126 sright = convert_thread_to_port_pinned(new_thread);
6127 task_t new_task = get_threadtask(new_thread);
6128 mach_port_name_t name = ipc_port_copyout_send(sright, get_task_ipcspace(new_task));
6129 char port_name_hex_str[strlen(MAIN_TH_PORT_KEY) + HEX_STR_LEN32 + 1];
6130 snprintf(port_name_hex_str, sizeof(port_name_hex_str), MAIN_TH_PORT_KEY "0x%x", name);
6131
6132 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(port_name_hex_str), UIO_SYSSPACE, FALSE);
6133 if (error) {
6134 goto bad;
6135 }
6136 imgp->ip_applec++;
6137 }
6138
6139 #if XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES
6140 if (imgp->ip_px_sa != NULL) {
6141 struct _posix_spawnattr* psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
6142 if (psa->psa_flags & _POSIX_SPAWN_FORCE_4K_PAGES) {
6143 const char *vm_force_4k_string = VM_FORCE_4K_PAGES_KEY;
6144 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(vm_force_4k_string), UIO_SYSSPACE, FALSE);
6145 if (error) {
6146 goto bad;
6147 }
6148 imgp->ip_applec++;
6149 }
6150 }
6151 #endif /* XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES */
6152
6153 /* adding the libmalloc experiment string */
6154 local_experiment_factors = os_atomic_load_wide(&libmalloc_experiment_factors, relaxed);
6155 if (__improbable(local_experiment_factors != 0)) {
6156 char libmalloc_experiment_factors_string[strlen(LIBMALLOC_EXPERIMENT_FACTORS_KEY) + HEX_STR_LEN + 1];
6157
6158 snprintf(
6159 libmalloc_experiment_factors_string,
6160 sizeof(libmalloc_experiment_factors_string),
6161 LIBMALLOC_EXPERIMENT_FACTORS_KEY "0x%llx",
6162 local_experiment_factors);
6163 error = exec_add_user_string(
6164 imgp,
6165 CAST_USER_ADDR_T(libmalloc_experiment_factors_string),
6166 UIO_SYSSPACE,
6167 FALSE);
6168 if (error) {
6169 printf("Failed to add the libmalloc experiment factors string with error %d\n", error);
6170 goto bad;
6171 }
6172 imgp->ip_applec++;
6173 }
6174
6175 /* tell dyld that it can leverage hardware for its read-only/read-write trusted path */
6176 if (imgp->ip_flags & IMGPF_HW_TPRO) {
6177 const char *dyld_hw_tpro = "dyld_hw_tpro=1";
6178 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_hw_tpro), UIO_SYSSPACE, FALSE);
6179 if (error) {
6180 printf("Failed to add dyld hw tpro setting with error %d\n", error);
6181 goto bad;
6182 }
6183
6184 imgp->ip_applec++;
6185 }
6186
6187 /* Align the tail of the combined applev area */
6188 while (imgp->ip_strspace % img_ptr_size != 0) {
6189 *imgp->ip_strendp++ = '\0';
6190 imgp->ip_strspace--;
6191 }
6192
6193 bad:
6194 return error;
6195 }
6196
6197 /*
6198 * exec_check_permissions
6199 *
6200 * Description: Verify that the file that is being attempted to be executed
6201 * is in fact allowed to be executed based on it POSIX file
6202 * permissions and other access control criteria
6203 *
6204 * Parameters: struct image_params * the image parameter block
6205 *
6206 * Returns: 0 Success
6207 * EACCES Permission denied
6208 * ENOEXEC Executable file format error
6209 * ETXTBSY Text file busy [misuse of error code]
6210 * vnode_getattr:???
6211 * vnode_authorize:???
6212 */
6213 static int
exec_check_permissions(struct image_params * imgp)6214 exec_check_permissions(struct image_params *imgp)
6215 {
6216 struct vnode *vp = imgp->ip_vp;
6217 struct vnode_attr *vap = imgp->ip_vattr;
6218 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
6219 int error;
6220 kauth_action_t action;
6221
6222 /* Only allow execution of regular files */
6223 if (!vnode_isreg(vp)) {
6224 return EACCES;
6225 }
6226
6227 /* Get the file attributes that we will be using here and elsewhere */
6228 VATTR_INIT(vap);
6229 VATTR_WANTED(vap, va_uid);
6230 VATTR_WANTED(vap, va_gid);
6231 VATTR_WANTED(vap, va_mode);
6232 VATTR_WANTED(vap, va_fsid);
6233 VATTR_WANTED(vap, va_fsid64);
6234 VATTR_WANTED(vap, va_fileid);
6235 VATTR_WANTED(vap, va_data_size);
6236 if ((error = vnode_getattr(vp, vap, imgp->ip_vfs_context)) != 0) {
6237 return error;
6238 }
6239
6240 /*
6241 * Ensure that at least one execute bit is on - otherwise root
6242 * will always succeed, and we don't want to happen unless the
6243 * file really is executable.
6244 */
6245 if (!vfs_authopaque(vnode_mount(vp)) && ((vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)) {
6246 return EACCES;
6247 }
6248
6249 /* Disallow zero length files */
6250 if (vap->va_data_size == 0) {
6251 return ENOEXEC;
6252 }
6253
6254 imgp->ip_arch_offset = (user_size_t)0;
6255 #if __LP64__
6256 imgp->ip_arch_size = vap->va_data_size;
6257 #else
6258 if (vap->va_data_size > UINT32_MAX) {
6259 return ENOEXEC;
6260 }
6261 imgp->ip_arch_size = (user_size_t)vap->va_data_size;
6262 #endif
6263
6264 /* Disable setuid-ness for traced programs or if MNT_NOSUID */
6265 if ((vp->v_mount->mnt_flag & MNT_NOSUID) || (p->p_lflag & P_LTRACED)) {
6266 vap->va_mode &= ~(VSUID | VSGID);
6267 }
6268
6269 /*
6270 * Disable _POSIX_SPAWN_ALLOW_DATA_EXEC and _POSIX_SPAWN_DISABLE_ASLR
6271 * flags for setuid/setgid binaries.
6272 */
6273 if (vap->va_mode & (VSUID | VSGID)) {
6274 imgp->ip_flags &= ~(IMGPF_ALLOW_DATA_EXEC | IMGPF_DISABLE_ASLR);
6275 }
6276
6277 #if CONFIG_MACF
6278 error = mac_vnode_check_exec(imgp->ip_vfs_context, vp, imgp);
6279 if (error) {
6280 return error;
6281 }
6282 #endif
6283
6284 /* Check for execute permission */
6285 action = KAUTH_VNODE_EXECUTE;
6286 /* Traced images must also be readable */
6287 if (p->p_lflag & P_LTRACED) {
6288 action |= KAUTH_VNODE_READ_DATA;
6289 }
6290 if ((error = vnode_authorize(vp, NULL, action, imgp->ip_vfs_context)) != 0) {
6291 return error;
6292 }
6293
6294 #if 0
6295 /* Don't let it run if anyone had it open for writing */
6296 vnode_lock(vp);
6297 if (vp->v_writecount) {
6298 panic("going to return ETXTBSY %x", vp);
6299 vnode_unlock(vp);
6300 return ETXTBSY;
6301 }
6302 vnode_unlock(vp);
6303 #endif
6304
6305 /* XXX May want to indicate to underlying FS that vnode is open */
6306
6307 return error;
6308 }
6309
6310
6311 /*
6312 * exec_handle_sugid
6313 *
6314 * Initially clear the P_SUGID in the process flags; if an SUGID process is
6315 * exec'ing a non-SUGID image, then this is the point of no return.
6316 *
6317 * If the image being activated is SUGID, then replace the credential with a
6318 * copy, disable tracing (unless the tracing process is root), reset the
6319 * mach task port to revoke it, set the P_SUGID bit,
6320 *
6321 * If the saved user and group ID will be changing, then make sure it happens
6322 * to a new credential, rather than a shared one.
6323 *
6324 * Set the security token (this is probably obsolete, given that the token
6325 * should not technically be separate from the credential itself).
6326 *
6327 * Parameters: struct image_params * the image parameter block
6328 *
6329 * Returns: void No failure indication
6330 *
6331 * Implicit returns:
6332 * <process credential> Potentially modified/replaced
6333 * <task port> Potentially revoked
6334 * <process flags> P_SUGID bit potentially modified
6335 * <security token> Potentially modified
6336 */
6337 __attribute__((noinline))
6338 static int
exec_handle_sugid(struct image_params * imgp)6339 exec_handle_sugid(struct image_params *imgp)
6340 {
6341 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
6342 kauth_cred_t cred = vfs_context_ucred(imgp->ip_vfs_context);
6343 int i;
6344 int leave_sugid_clear = 0;
6345 int mac_reset_ipc = 0;
6346 int error = 0;
6347 task_t task = NULL;
6348 #if CONFIG_MACF
6349 int mac_transition, disjoint_cred = 0;
6350 int label_update_return = 0;
6351
6352 /*
6353 * Determine whether a call to update the MAC label will result in the
6354 * credential changing.
6355 *
6356 * Note: MAC policies which do not actually end up modifying
6357 * the label subsequently are strongly encouraged to
6358 * return 0 for this check, since a non-zero answer will
6359 * slow down the exec fast path for normal binaries.
6360 */
6361 mac_transition = mac_cred_check_label_update_execve(
6362 imgp->ip_vfs_context,
6363 imgp->ip_vp,
6364 imgp->ip_arch_offset,
6365 imgp->ip_scriptvp,
6366 imgp->ip_scriptlabelp,
6367 imgp->ip_execlabelp,
6368 p,
6369 &imgp->ip_px_smpx);
6370 #endif
6371
6372 OSBitAndAtomic(~((uint32_t)P_SUGID), &p->p_flag);
6373
6374 /*
6375 * Order of the following is important; group checks must go last,
6376 * as we use the success of the 'ismember' check combined with the
6377 * failure of the explicit match to indicate that we will be setting
6378 * the egid of the process even though the new process did not
6379 * require VSUID/VSGID bits in order for it to set the new group as
6380 * its egid.
6381 *
6382 * Note: Technically, by this we are implying a call to
6383 * setegid() in the new process, rather than implying
6384 * it used its VSGID bit to set the effective group,
6385 * even though there is no code in that process to make
6386 * such a call.
6387 */
6388 if (((imgp->ip_origvattr->va_mode & VSUID) != 0 &&
6389 kauth_cred_getuid(cred) != imgp->ip_origvattr->va_uid) ||
6390 ((imgp->ip_origvattr->va_mode & VSGID) != 0 &&
6391 ((kauth_cred_ismember_gid(cred, imgp->ip_origvattr->va_gid, &leave_sugid_clear) || !leave_sugid_clear) ||
6392 (kauth_cred_getgid(cred) != imgp->ip_origvattr->va_gid)))) {
6393 #if CONFIG_MACF
6394 /* label for MAC transition and neither VSUID nor VSGID */
6395 handle_mac_transition:
6396 #endif
6397
6398 #if CONFIG_SETUID
6399 /*
6400 * Replace the credential with a copy of itself if euid or
6401 * egid change.
6402 *
6403 * Note: setuid binaries will automatically opt out of
6404 * group resolver participation as a side effect
6405 * of this operation. This is an intentional
6406 * part of the security model, which requires a
6407 * participating credential be established by
6408 * escalating privilege, setting up all other
6409 * aspects of the credential including whether
6410 * or not to participate in external group
6411 * membership resolution, then dropping their
6412 * effective privilege to that of the desired
6413 * final credential state.
6414 *
6415 * Modifications to p_ucred must be guarded using the
6416 * proc's ucred lock. This prevents others from accessing
6417 * a garbage credential.
6418 */
6419
6420 if (imgp->ip_origvattr->va_mode & VSUID) {
6421 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred) {
6422 return kauth_cred_setresuid(my_cred,
6423 KAUTH_UID_NONE,
6424 imgp->ip_origvattr->va_uid,
6425 imgp->ip_origvattr->va_uid,
6426 KAUTH_UID_NONE);
6427 });
6428 }
6429
6430 if (imgp->ip_origvattr->va_mode & VSGID) {
6431 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred) {
6432 return kauth_cred_setresgid(my_cred,
6433 KAUTH_GID_NONE,
6434 imgp->ip_origvattr->va_gid,
6435 imgp->ip_origvattr->va_gid);
6436 });
6437 }
6438 #endif /* CONFIG_SETUID */
6439
6440 #if CONFIG_MACF
6441 /*
6442 * If a policy has indicated that it will transition the label,
6443 * before making the call into the MAC policies, get a new
6444 * duplicate credential, so they can modify it without
6445 * modifying any others sharing it.
6446 */
6447 if (mac_transition) {
6448 /*
6449 * This hook may generate upcalls that require
6450 * importance donation from the kernel.
6451 * (23925818)
6452 */
6453 thread_t thread = current_thread();
6454 thread_enable_send_importance(thread, TRUE);
6455 kauth_proc_label_update_execve(p,
6456 imgp->ip_vfs_context,
6457 imgp->ip_vp,
6458 imgp->ip_arch_offset,
6459 imgp->ip_scriptvp,
6460 imgp->ip_scriptlabelp,
6461 imgp->ip_execlabelp,
6462 &imgp->ip_csflags,
6463 &imgp->ip_px_smpx,
6464 &disjoint_cred, /* will be non zero if disjoint */
6465 &label_update_return);
6466 thread_enable_send_importance(thread, FALSE);
6467
6468 if (disjoint_cred) {
6469 /*
6470 * If updating the MAC label resulted in a
6471 * disjoint credential, flag that we need to
6472 * set the P_SUGID bit. This protects
6473 * against debuggers being attached by an
6474 * insufficiently privileged process onto the
6475 * result of a transition to a more privileged
6476 * credential.
6477 */
6478 leave_sugid_clear = 0;
6479 }
6480
6481 imgp->ip_mac_return = label_update_return;
6482 }
6483
6484 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);
6485
6486 #endif /* CONFIG_MACF */
6487
6488 /*
6489 * If 'leave_sugid_clear' is non-zero, then we passed the
6490 * VSUID and MACF checks, and successfully determined that
6491 * the previous cred was a member of the VSGID group, but
6492 * that it was not the default at the time of the execve,
6493 * and that the post-labelling credential was not disjoint.
6494 * So we don't set the P_SUGID or reset mach ports and fds
6495 * on the basis of simply running this code.
6496 */
6497 if (mac_reset_ipc || !leave_sugid_clear) {
6498 /*
6499 * Have mach reset the task and thread ports.
6500 * We don't want anyone who had the ports before
6501 * a setuid exec to be able to access/control the
6502 * task/thread after.
6503 */
6504 ipc_task_reset((imgp->ip_new_thread != NULL) ?
6505 get_threadtask(imgp->ip_new_thread) : proc_task(p));
6506 ipc_thread_reset((imgp->ip_new_thread != NULL) ?
6507 imgp->ip_new_thread : current_thread());
6508 }
6509
6510 if (!leave_sugid_clear) {
6511 /*
6512 * Flag the process as setuid.
6513 */
6514 OSBitOrAtomic(P_SUGID, &p->p_flag);
6515
6516 /*
6517 * Radar 2261856; setuid security hole fix
6518 * XXX For setuid processes, attempt to ensure that
6519 * stdin, stdout, and stderr are already allocated.
6520 * We do not want userland to accidentally allocate
6521 * descriptors in this range which has implied meaning
6522 * to libc.
6523 */
6524 for (i = 0; i < 3; i++) {
6525 if (fp_get_noref_locked(p, i) != NULL) {
6526 continue;
6527 }
6528
6529 /*
6530 * Do the kernel equivalent of
6531 *
6532 * if i == 0
6533 * (void) open("/dev/null", O_RDONLY);
6534 * else
6535 * (void) open("/dev/null", O_WRONLY);
6536 */
6537
6538 struct fileproc *fp;
6539 int indx;
6540 int flag;
6541 struct nameidata *ndp = NULL;
6542
6543 if (i == 0) {
6544 flag = FREAD;
6545 } else {
6546 flag = FWRITE;
6547 }
6548
6549 if ((error = falloc(p,
6550 &fp, &indx, imgp->ip_vfs_context)) != 0) {
6551 continue;
6552 }
6553
6554 ndp = kalloc_type(struct nameidata,
6555 Z_WAITOK | Z_ZERO | Z_NOFAIL);
6556
6557 NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW, UIO_SYSSPACE,
6558 CAST_USER_ADDR_T("/dev/null"),
6559 imgp->ip_vfs_context);
6560
6561 if ((error = vn_open(ndp, flag, 0)) != 0) {
6562 fp_free(p, indx, fp);
6563 kfree_type(struct nameidata, ndp);
6564 break;
6565 }
6566
6567 struct fileglob *fg = fp->fp_glob;
6568
6569 fg->fg_flag = flag;
6570 fg->fg_ops = &vnops;
6571 fp_set_data(fp, ndp->ni_vp);
6572
6573 vnode_put(ndp->ni_vp);
6574
6575 proc_fdlock(p);
6576 procfdtbl_releasefd(p, indx, NULL);
6577 fp_drop(p, indx, fp, 1);
6578 proc_fdunlock(p);
6579
6580 kfree_type(struct nameidata, ndp);
6581 }
6582 }
6583 }
6584 #if CONFIG_MACF
6585 else {
6586 /*
6587 * We are here because we were told that the MAC label will
6588 * be transitioned, and the binary is not VSUID or VSGID; to
6589 * deal with this case, we could either duplicate a lot of
6590 * code, or we can indicate we want to default the P_SUGID
6591 * bit clear and jump back up.
6592 */
6593 if (mac_transition) {
6594 leave_sugid_clear = 1;
6595 goto handle_mac_transition;
6596 }
6597 }
6598
6599 #endif /* CONFIG_MACF */
6600
6601 /*
6602 * Implement the semantic where the effective user and group become
6603 * the saved user and group in exec'ed programs.
6604 *
6605 * Modifications to p_ucred must be guarded using the
6606 * proc's ucred lock. This prevents others from accessing
6607 * a garbage credential.
6608 */
6609 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred) {
6610 return kauth_cred_setsvuidgid(my_cred,
6611 kauth_cred_getuid(my_cred),
6612 kauth_cred_getgid(my_cred));
6613 });
6614
6615 if (imgp->ip_new_thread != NULL) {
6616 task = get_threadtask(imgp->ip_new_thread);
6617 } else {
6618 task = proc_task(p);
6619 }
6620
6621 /* Update the process' identity version and set the security token */
6622 proc_setpidversion(p, OSIncrementAtomic(&nextpidversion));
6623 task_set_uniqueid(task);
6624 set_security_token_task_internal(p, task);
6625
6626 return error;
6627 }
6628
6629
6630 /*
6631 * create_unix_stack
6632 *
6633 * Description: Set the user stack address for the process to the provided
6634 * address. If a custom stack was not set as a result of the
6635 * load process (i.e. as specified by the image file for the
6636 * executable), then allocate the stack in the provided map and
6637 * set up appropriate guard pages for enforcing administrative
6638 * limits on stack growth, if they end up being needed.
6639 *
6640 * Parameters: p Process to set stack on
6641 * load_result Information from mach-o load commands
6642 * map Address map in which to allocate the new stack
6643 *
6644 * Returns: KERN_SUCCESS Stack successfully created
6645 * !KERN_SUCCESS Mach failure code
6646 */
6647 __attribute__((noinline))
6648 static kern_return_t
create_unix_stack(vm_map_t map,load_result_t * load_result,proc_t p)6649 create_unix_stack(vm_map_t map, load_result_t* load_result,
6650 proc_t p)
6651 {
6652 mach_vm_size_t size, prot_size;
6653 mach_vm_offset_t addr, prot_addr;
6654 kern_return_t kr;
6655
6656 mach_vm_address_t user_stack = load_result->user_stack;
6657
6658 proc_lock(p);
6659 p->user_stack = (uintptr_t)user_stack;
6660 if (load_result->custom_stack) {
6661 p->p_lflag |= P_LCUSTOM_STACK;
6662 }
6663 proc_unlock(p);
6664 if (vm_map_page_shift(map) < (int)PAGE_SHIFT) {
6665 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);
6666 }
6667
6668 if (load_result->user_stack_alloc_size > 0) {
6669 /*
6670 * Allocate enough space for the maximum stack size we
6671 * will ever authorize and an extra page to act as
6672 * a guard page for stack overflows. For default stacks,
6673 * vm_initial_limit_stack takes care of the extra guard page.
6674 * Otherwise we must allocate it ourselves.
6675 */
6676 if (mach_vm_round_page_overflow(load_result->user_stack_alloc_size, &size)) {
6677 return KERN_INVALID_ARGUMENT;
6678 }
6679 addr = vm_map_trunc_page(load_result->user_stack - size,
6680 vm_map_page_mask(map));
6681 kr = mach_vm_allocate_kernel(map, &addr, size,
6682 VM_FLAGS_FIXED, VM_MEMORY_STACK);
6683 if (kr != KERN_SUCCESS) {
6684 // Can't allocate at default location, try anywhere
6685 addr = 0;
6686 kr = mach_vm_allocate_kernel(map, &addr, size,
6687 VM_FLAGS_ANYWHERE, VM_MEMORY_STACK);
6688 if (kr != KERN_SUCCESS) {
6689 return kr;
6690 }
6691
6692 user_stack = addr + size;
6693 load_result->user_stack = (user_addr_t)user_stack;
6694
6695 proc_lock(p);
6696 p->user_stack = (uintptr_t)user_stack;
6697 proc_unlock(p);
6698 }
6699
6700 load_result->user_stack_alloc = (user_addr_t)addr;
6701
6702 /*
6703 * And prevent access to what's above the current stack
6704 * size limit for this process.
6705 */
6706 if (load_result->user_stack_size == 0) {
6707 load_result->user_stack_size = proc_limitgetcur(p, RLIMIT_STACK);
6708 prot_size = vm_map_trunc_page(size - load_result->user_stack_size, vm_map_page_mask(map));
6709 } else {
6710 prot_size = PAGE_SIZE;
6711 }
6712
6713 prot_addr = addr;
6714 kr = mach_vm_protect(map,
6715 prot_addr,
6716 prot_size,
6717 FALSE,
6718 VM_PROT_NONE);
6719 if (kr != KERN_SUCCESS) {
6720 (void)mach_vm_deallocate(map, addr, size);
6721 return kr;
6722 }
6723 }
6724
6725 return KERN_SUCCESS;
6726 }
6727
6728 #include <sys/reboot.h>
6729
6730 /*
6731 * load_init_program_at_path
6732 *
6733 * Description: Load the "init" program; in most cases, this will be "launchd"
6734 *
6735 * Parameters: p Process to call execve() to create
6736 * the "init" program
6737 * scratch_addr Page in p, scratch space
6738 * path NULL terminated path
6739 *
6740 * Returns: KERN_SUCCESS Success
6741 * !KERN_SUCCESS See execve/mac_execve for error codes
6742 *
6743 * Notes: The process that is passed in is the first manufactured
6744 * process on the system, and gets here via bsd_ast() firing
6745 * for the first time. This is done to ensure that bsd_init()
6746 * has run to completion.
6747 *
6748 * The address map of the first manufactured process matches the
6749 * word width of the kernel. Once the self-exec completes, the
6750 * initproc might be different.
6751 */
6752 static int
load_init_program_at_path(proc_t p,user_addr_t scratch_addr,const char * path)6753 load_init_program_at_path(proc_t p, user_addr_t scratch_addr, const char* path)
6754 {
6755 int retval[2];
6756 int error;
6757 struct execve_args init_exec_args;
6758 user_addr_t argv0 = USER_ADDR_NULL, argv1 = USER_ADDR_NULL;
6759
6760 /*
6761 * Validate inputs and pre-conditions
6762 */
6763 assert(p);
6764 assert(scratch_addr);
6765 assert(path);
6766
6767 /*
6768 * Copy out program name.
6769 */
6770 size_t path_length = strlen(path) + 1;
6771 argv0 = scratch_addr;
6772 error = copyout(path, argv0, path_length);
6773 if (error) {
6774 return error;
6775 }
6776
6777 scratch_addr = USER_ADDR_ALIGN(scratch_addr + path_length, sizeof(user_addr_t));
6778
6779 /*
6780 * Put out first (and only) argument, similarly.
6781 * Assumes everything fits in a page as allocated above.
6782 */
6783 if (boothowto & RB_SINGLE) {
6784 const char *init_args = "-s";
6785 size_t init_args_length = strlen(init_args) + 1;
6786
6787 argv1 = scratch_addr;
6788 error = copyout(init_args, argv1, init_args_length);
6789 if (error) {
6790 return error;
6791 }
6792
6793 scratch_addr = USER_ADDR_ALIGN(scratch_addr + init_args_length, sizeof(user_addr_t));
6794 }
6795
6796 if (proc_is64bit(p)) {
6797 user64_addr_t argv64bit[3] = {};
6798
6799 argv64bit[0] = argv0;
6800 argv64bit[1] = argv1;
6801 argv64bit[2] = USER_ADDR_NULL;
6802
6803 error = copyout(argv64bit, scratch_addr, sizeof(argv64bit));
6804 if (error) {
6805 return error;
6806 }
6807 } else {
6808 user32_addr_t argv32bit[3] = {};
6809
6810 argv32bit[0] = (user32_addr_t)argv0;
6811 argv32bit[1] = (user32_addr_t)argv1;
6812 argv32bit[2] = USER_ADDR_NULL;
6813
6814 error = copyout(argv32bit, scratch_addr, sizeof(argv32bit));
6815 if (error) {
6816 return error;
6817 }
6818 }
6819
6820 /*
6821 * Set up argument block for fake call to execve.
6822 */
6823 init_exec_args.fname = argv0;
6824 init_exec_args.argp = scratch_addr;
6825 init_exec_args.envp = USER_ADDR_NULL;
6826
6827 /*
6828 * So that init task is set with uid,gid 0 token
6829 */
6830 set_security_token(p);
6831
6832 return execve(p, &init_exec_args, retval);
6833 }
6834
6835 static const char * init_programs[] = {
6836 #if DEBUG
6837 "/usr/appleinternal/sbin/launchd.debug",
6838 #endif
6839 #if DEVELOPMENT || DEBUG
6840 "/usr/appleinternal/sbin/launchd.development",
6841 #endif
6842 "/sbin/launchd",
6843 };
6844
6845 /*
6846 * load_init_program
6847 *
6848 * Description: Load the "init" program; in most cases, this will be "launchd"
6849 *
6850 * Parameters: p Process to call execve() to create
6851 * the "init" program
6852 *
6853 * Returns: (void)
6854 *
6855 * Notes: The process that is passed in is the first manufactured
6856 * process on the system, and gets here via bsd_ast() firing
6857 * for the first time. This is done to ensure that bsd_init()
6858 * has run to completion.
6859 *
6860 * In DEBUG & DEVELOPMENT builds, the launchdsuffix boot-arg
6861 * may be used to select a specific launchd executable. As with
6862 * the kcsuffix boot-arg, setting launchdsuffix to "" or "release"
6863 * will force /sbin/launchd to be selected.
6864 *
6865 * Search order by build:
6866 *
6867 * DEBUG DEVELOPMENT RELEASE PATH
6868 * ----------------------------------------------------------------------------------
6869 * 1 1 NA /usr/appleinternal/sbin/launchd.$LAUNCHDSUFFIX
6870 * 2 NA NA /usr/appleinternal/sbin/launchd.debug
6871 * 3 2 NA /usr/appleinternal/sbin/launchd.development
6872 * 4 3 1 /sbin/launchd
6873 */
6874 void
load_init_program(proc_t p)6875 load_init_program(proc_t p)
6876 {
6877 uint32_t i;
6878 int error;
6879 vm_map_t map = current_map();
6880 mach_vm_offset_t scratch_addr = 0;
6881 mach_vm_size_t map_page_size = vm_map_page_size(map);
6882
6883 (void) mach_vm_allocate_kernel(map, &scratch_addr, map_page_size, VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_NONE);
6884 #if CONFIG_MEMORYSTATUS
6885 (void) memorystatus_init_at_boot_snapshot();
6886 #endif /* CONFIG_MEMORYSTATUS */
6887
6888 #if DEBUG || DEVELOPMENT
6889 /* Check for boot-arg suffix first */
6890 char launchd_suffix[64];
6891 if (PE_parse_boot_argn("launchdsuffix", launchd_suffix, sizeof(launchd_suffix))) {
6892 char launchd_path[128];
6893 boolean_t is_release_suffix = ((launchd_suffix[0] == 0) ||
6894 (strcmp(launchd_suffix, "release") == 0));
6895
6896 if (is_release_suffix) {
6897 printf("load_init_program: attempting to load /sbin/launchd\n");
6898 error = load_init_program_at_path(p, (user_addr_t)scratch_addr, "/sbin/launchd");
6899 if (!error) {
6900 return;
6901 }
6902
6903 panic("Process 1 exec of launchd.release failed, errno %d", error);
6904 } else {
6905 strlcpy(launchd_path, "/usr/appleinternal/sbin/launchd.", sizeof(launchd_path));
6906 strlcat(launchd_path, launchd_suffix, sizeof(launchd_path));
6907
6908 printf("load_init_program: attempting to load %s\n", launchd_path);
6909 error = load_init_program_at_path(p, (user_addr_t)scratch_addr, launchd_path);
6910 if (!error) {
6911 return;
6912 } else if (error != ENOENT) {
6913 printf("load_init_program: failed loading %s: errno %d\n", launchd_path, error);
6914 }
6915 }
6916 }
6917 #endif
6918
6919 error = ENOENT;
6920 for (i = 0; i < sizeof(init_programs) / sizeof(init_programs[0]); i++) {
6921 printf("load_init_program: attempting to load %s\n", init_programs[i]);
6922 error = load_init_program_at_path(p, (user_addr_t)scratch_addr, init_programs[i]);
6923 if (!error) {
6924 return;
6925 } else if (error != ENOENT) {
6926 printf("load_init_program: failed loading %s: errno %d\n", init_programs[i], error);
6927 }
6928 }
6929
6930 panic("Process 1 exec of %s failed, errno %d", ((i == 0) ? "<null>" : init_programs[i - 1]), error);
6931 }
6932
6933 /*
6934 * load_return_to_errno
6935 *
6936 * Description: Convert a load_return_t (Mach error) to an errno (BSD error)
6937 *
6938 * Parameters: lrtn Mach error number
6939 *
6940 * Returns: (int) BSD error number
6941 * 0 Success
6942 * EBADARCH Bad architecture
6943 * EBADMACHO Bad Mach object file
6944 * ESHLIBVERS Bad shared library version
6945 * ENOMEM Out of memory/resource shortage
6946 * EACCES Access denied
6947 * ENOENT Entry not found (usually "file does
6948 * does not exist")
6949 * EIO An I/O error occurred
6950 * EBADEXEC The executable is corrupt/unknown
6951 */
6952 static int
load_return_to_errno(load_return_t lrtn)6953 load_return_to_errno(load_return_t lrtn)
6954 {
6955 switch (lrtn) {
6956 case LOAD_SUCCESS:
6957 return 0;
6958 case LOAD_BADARCH:
6959 return EBADARCH;
6960 case LOAD_BADMACHO:
6961 case LOAD_BADMACHO_UPX:
6962 return EBADMACHO;
6963 case LOAD_SHLIB:
6964 return ESHLIBVERS;
6965 case LOAD_NOSPACE:
6966 case LOAD_RESOURCE:
6967 return ENOMEM;
6968 case LOAD_PROTECT:
6969 return EACCES;
6970 case LOAD_ENOENT:
6971 return ENOENT;
6972 case LOAD_IOERROR:
6973 return EIO;
6974 case LOAD_DECRYPTFAIL:
6975 return EAUTH;
6976 case LOAD_FAILURE:
6977 default:
6978 return EBADEXEC;
6979 }
6980 }
6981
6982 #include <mach/mach_types.h>
6983 #include <mach/vm_prot.h>
6984 #include <mach/semaphore.h>
6985 #include <mach/sync_policy.h>
6986 #include <kern/clock.h>
6987 #include <mach/kern_return.h>
6988
6989 /*
6990 * execargs_alloc
6991 *
6992 * Description: Allocate the block of memory used by the execve arguments.
6993 * At the same time, we allocate a page so that we can read in
6994 * the first page of the image.
6995 *
6996 * Parameters: struct image_params * the image parameter block
6997 *
6998 * Returns: 0 Success
6999 * EINVAL Invalid argument
7000 * EACCES Permission denied
7001 * EINTR Interrupted function
7002 * ENOMEM Not enough space
7003 *
7004 * Notes: This is a temporary allocation into the kernel address space
7005 * to enable us to copy arguments in from user space. This is
7006 * necessitated by not mapping the process calling execve() into
7007 * the kernel address space during the execve() system call.
7008 *
7009 * We assemble the argument and environment, etc., into this
7010 * region before copying it as a single block into the child
7011 * process address space (at the top or bottom of the stack,
7012 * depending on which way the stack grows; see the function
7013 * exec_copyout_strings() for details).
7014 *
7015 * This ends up with a second (possibly unnecessary) copy compared
7016 * with assembing the data directly into the child address space,
7017 * instead, but since we cannot be guaranteed that the parent has
7018 * not modified its environment, we can't really know that it's
7019 * really a block there as well.
7020 */
7021
7022
7023 static int execargs_waiters = 0;
7024 static LCK_MTX_DECLARE_ATTR(execargs_cache_lock, &proc_lck_grp, &proc_lck_attr);
7025
7026 static void
execargs_lock_lock(void)7027 execargs_lock_lock(void)
7028 {
7029 lck_mtx_lock_spin(&execargs_cache_lock);
7030 }
7031
7032 static void
execargs_lock_unlock(void)7033 execargs_lock_unlock(void)
7034 {
7035 lck_mtx_unlock(&execargs_cache_lock);
7036 }
7037
7038 static wait_result_t
execargs_lock_sleep(void)7039 execargs_lock_sleep(void)
7040 {
7041 return lck_mtx_sleep(&execargs_cache_lock, LCK_SLEEP_DEFAULT, &execargs_free_count, THREAD_INTERRUPTIBLE);
7042 }
7043
7044 static kern_return_t
execargs_purgeable_allocate(char ** execarg_address)7045 execargs_purgeable_allocate(char **execarg_address)
7046 {
7047 mach_vm_offset_t addr = 0;
7048 kern_return_t kr = mach_vm_allocate_kernel(bsd_pageable_map, &addr,
7049 BSD_PAGEABLE_SIZE_PER_EXEC, VM_FLAGS_ANYWHERE | VM_FLAGS_PURGABLE,
7050 VM_KERN_MEMORY_NONE);
7051 *execarg_address = (char *)addr;
7052 assert(kr == KERN_SUCCESS);
7053 return kr;
7054 }
7055
7056 static kern_return_t
execargs_purgeable_reference(void * execarg_address)7057 execargs_purgeable_reference(void *execarg_address)
7058 {
7059 int state = VM_PURGABLE_NONVOLATILE;
7060 kern_return_t kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
7061
7062 assert(kr == KERN_SUCCESS);
7063 return kr;
7064 }
7065
7066 static kern_return_t
execargs_purgeable_volatilize(void * execarg_address)7067 execargs_purgeable_volatilize(void *execarg_address)
7068 {
7069 int state = VM_PURGABLE_VOLATILE | VM_PURGABLE_ORDERING_OBSOLETE;
7070 kern_return_t kr;
7071 kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
7072
7073 assert(kr == KERN_SUCCESS);
7074
7075 return kr;
7076 }
7077
7078 static void
execargs_wakeup_waiters(void)7079 execargs_wakeup_waiters(void)
7080 {
7081 thread_wakeup(&execargs_free_count);
7082 }
7083
7084 static int
execargs_alloc(struct image_params * imgp)7085 execargs_alloc(struct image_params *imgp)
7086 {
7087 kern_return_t kret;
7088 wait_result_t res;
7089 int i, cache_index = -1;
7090
7091 execargs_lock_lock();
7092
7093 while (execargs_free_count == 0) {
7094 execargs_waiters++;
7095 res = execargs_lock_sleep();
7096 execargs_waiters--;
7097 if (res != THREAD_AWAKENED) {
7098 execargs_lock_unlock();
7099 return EINTR;
7100 }
7101 }
7102
7103 execargs_free_count--;
7104
7105 for (i = 0; i < execargs_cache_size; i++) {
7106 vm_offset_t element = execargs_cache[i];
7107 if (element) {
7108 cache_index = i;
7109 imgp->ip_strings = (char *)(execargs_cache[i]);
7110 execargs_cache[i] = 0;
7111 break;
7112 }
7113 }
7114
7115 assert(execargs_free_count >= 0);
7116
7117 execargs_lock_unlock();
7118
7119 if (cache_index == -1) {
7120 kret = execargs_purgeable_allocate(&imgp->ip_strings);
7121 } else {
7122 kret = execargs_purgeable_reference(imgp->ip_strings);
7123 }
7124
7125 assert(kret == KERN_SUCCESS);
7126 if (kret != KERN_SUCCESS) {
7127 return ENOMEM;
7128 }
7129
7130 /* last page used to read in file headers */
7131 imgp->ip_vdata = imgp->ip_strings + (NCARGS + PAGE_SIZE);
7132 imgp->ip_strendp = imgp->ip_strings;
7133 imgp->ip_argspace = NCARGS;
7134 imgp->ip_strspace = (NCARGS + PAGE_SIZE);
7135
7136 return 0;
7137 }
7138
7139 /*
7140 * execargs_free
7141 *
7142 * Description: Free the block of memory used by the execve arguments and the
7143 * first page of the executable by a previous call to the function
7144 * execargs_alloc().
7145 *
7146 * Parameters: struct image_params * the image parameter block
7147 *
7148 * Returns: 0 Success
7149 * EINVAL Invalid argument
7150 * EINTR Oeration interrupted
7151 */
7152 static int
execargs_free(struct image_params * imgp)7153 execargs_free(struct image_params *imgp)
7154 {
7155 kern_return_t kret;
7156 int i;
7157 boolean_t needs_wakeup = FALSE;
7158
7159 kret = execargs_purgeable_volatilize(imgp->ip_strings);
7160
7161 execargs_lock_lock();
7162 execargs_free_count++;
7163
7164 for (i = 0; i < execargs_cache_size; i++) {
7165 vm_offset_t element = execargs_cache[i];
7166 if (element == 0) {
7167 execargs_cache[i] = (vm_offset_t) imgp->ip_strings;
7168 imgp->ip_strings = NULL;
7169 break;
7170 }
7171 }
7172
7173 assert(imgp->ip_strings == NULL);
7174
7175 if (execargs_waiters > 0) {
7176 needs_wakeup = TRUE;
7177 }
7178
7179 execargs_lock_unlock();
7180
7181 if (needs_wakeup == TRUE) {
7182 execargs_wakeup_waiters();
7183 }
7184
7185 return kret == KERN_SUCCESS ? 0 : EINVAL;
7186 }
7187
7188 void
uthread_set_exec_data(struct uthread * uth,struct image_params * imgp)7189 uthread_set_exec_data(struct uthread *uth, struct image_params *imgp)
7190 {
7191 uth->uu_save.uus_exec_data.imgp = imgp;
7192 }
7193
7194 size_t
thread_get_current_exec_path(char * path,size_t size)7195 thread_get_current_exec_path(char *path, size_t size)
7196 {
7197 struct uthread *uth = current_uthread();
7198 struct image_params *imgp = uth->uu_save.uus_exec_data.imgp;
7199 size_t string_size = 0;
7200 char *exec_path;
7201
7202 if (path == NULL || imgp == NULL || imgp->ip_strings == NULL) {
7203 return 0;
7204 }
7205
7206 exec_path = imgp->ip_strings + strlen(EXECUTABLE_KEY);
7207 string_size = imgp->ip_strendp - exec_path;
7208 string_size = MIN(MAXPATHLEN, string_size);
7209 string_size = MIN(size, string_size);
7210
7211 string_size = strlcpy(path, exec_path, string_size);
7212 return string_size;
7213 }
7214 static void
exec_resettextvp(proc_t p,struct image_params * imgp)7215 exec_resettextvp(proc_t p, struct image_params *imgp)
7216 {
7217 vnode_t vp;
7218 off_t offset;
7219 vnode_t tvp = p->p_textvp;
7220 int ret;
7221
7222 vp = imgp->ip_vp;
7223 offset = imgp->ip_arch_offset;
7224
7225 if (vp == NULLVP) {
7226 panic("exec_resettextvp: expected valid vp");
7227 }
7228
7229 ret = vnode_ref(vp);
7230 proc_lock(p);
7231 if (ret == 0) {
7232 p->p_textvp = vp;
7233 p->p_textoff = offset;
7234 } else {
7235 p->p_textvp = NULLVP; /* this is paranoia */
7236 p->p_textoff = 0;
7237 }
7238 proc_unlock(p);
7239
7240 if (tvp != NULLVP) {
7241 if (vnode_getwithref(tvp) == 0) {
7242 vnode_rele(tvp);
7243 vnode_put(tvp);
7244 }
7245 }
7246 }
7247
7248 // Includes the 0-byte (therefore "SIZE" instead of "LEN").
7249 static const size_t CS_CDHASH_STRING_SIZE = CS_CDHASH_LEN * 2 + 1;
7250
7251 static void
cdhash_to_string(char str[CS_CDHASH_STRING_SIZE],uint8_t const * const cdhash)7252 cdhash_to_string(char str[CS_CDHASH_STRING_SIZE], uint8_t const * const cdhash)
7253 {
7254 static char const nibble[] = "0123456789abcdef";
7255
7256 /* Apparently still the safest way to get a hex representation
7257 * of binary data.
7258 * xnu's printf routines have %*D/%20D in theory, but "not really", see:
7259 * <rdar://problem/33328859> confusion around %*D/%nD in printf
7260 */
7261 for (int i = 0; i < CS_CDHASH_LEN; ++i) {
7262 str[i * 2] = nibble[(cdhash[i] & 0xf0) >> 4];
7263 str[i * 2 + 1] = nibble[cdhash[i] & 0x0f];
7264 }
7265 str[CS_CDHASH_STRING_SIZE - 1] = 0;
7266 }
7267
7268 /*
7269 * __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__
7270 *
7271 * Description: Waits for the userspace daemon to respond to the request
7272 * we made. Function declared non inline to be visible in
7273 * stackshots and spindumps as well as debugging.
7274 */
7275 __attribute__((noinline)) int
__EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port,int32_t new_pid)7276 __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid)
7277 {
7278 return find_code_signature(task_access_port, new_pid);
7279 }
7280
7281 /*
7282 * Update signature dependent process state, called by
7283 * process_signature.
7284 */
7285 static int
proc_process_signature(proc_t p,os_reason_t * signature_failure_reason)7286 proc_process_signature(proc_t p, os_reason_t *signature_failure_reason)
7287 {
7288 int error = 0;
7289 char const *error_msg = NULL;
7290
7291 kern_return_t kr = machine_task_process_signature(proc_get_task_raw(p), proc_platform(p), proc_sdk(p), &error_msg);
7292
7293 if (kr != KERN_SUCCESS) {
7294 error = EINVAL;
7295
7296 if (error_msg != NULL) {
7297 uint32_t error_msg_len = (uint32_t)strlen(error_msg) + 1;
7298 mach_vm_address_t data_addr = 0;
7299 int reason_error = 0;
7300 int kcdata_error = 0;
7301
7302 os_reason_t reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
7303 reason->osr_flags = OS_REASON_FLAG_GENERATE_CRASH_REPORT | OS_REASON_FLAG_CONSISTENT_FAILURE;
7304
7305 if ((reason_error = os_reason_alloc_buffer_noblock(reason,
7306 kcdata_estimate_required_buffer_size(1, error_msg_len))) == 0 &&
7307 (kcdata_error = kcdata_get_memory_addr(&reason->osr_kcd_descriptor,
7308 EXIT_REASON_USER_DESC, error_msg_len,
7309 &data_addr)) == KERN_SUCCESS) {
7310 kern_return_t mc_error = kcdata_memcpy(&reason->osr_kcd_descriptor, (mach_vm_address_t)data_addr,
7311 error_msg, error_msg_len);
7312
7313 if (mc_error != KERN_SUCCESS) {
7314 printf("process_signature: failed to copy reason string (kcdata_memcpy error: %d)\n",
7315 mc_error);
7316 }
7317 } else {
7318 printf("failed to allocate space for reason string (os_reason_alloc_buffer error: %d, kcdata error: %d, length: %u)\n",
7319 reason_error, kcdata_error, error_msg_len);
7320 }
7321
7322 assert(*signature_failure_reason == NULL); // shouldn't have gotten so far
7323 *signature_failure_reason = reason;
7324 }
7325 }
7326 return error;
7327 }
7328
7329 static int
process_signature(proc_t p,struct image_params * imgp)7330 process_signature(proc_t p, struct image_params *imgp)
7331 {
7332 mach_port_t port = IPC_PORT_NULL;
7333 kern_return_t kr = KERN_FAILURE;
7334 int error = EACCES;
7335 boolean_t unexpected_failure = FALSE;
7336 struct cs_blob *csb;
7337 boolean_t require_success = FALSE;
7338 int spawn = (imgp->ip_flags & IMGPF_SPAWN);
7339 const int vfexec = 0;
7340 os_reason_t signature_failure_reason = OS_REASON_NULL;
7341
7342 /*
7343 * Override inherited code signing flags with the
7344 * ones for the process that is being successfully
7345 * loaded
7346 */
7347 proc_lock(p);
7348 proc_csflags_update(p, imgp->ip_csflags);
7349 proc_unlock(p);
7350
7351 /* Set the switch_protect flag on the map */
7352 if (proc_getcsflags(p) & (CS_HARD | CS_KILL)) {
7353 vm_map_switch_protect(get_task_map(proc_task(p)), TRUE);
7354 }
7355 /* set the cs_enforced flags in the map */
7356 if (proc_getcsflags(p) & CS_ENFORCEMENT) {
7357 vm_map_cs_enforcement_set(get_task_map(proc_task(p)), TRUE);
7358 } else {
7359 vm_map_cs_enforcement_set(get_task_map(proc_task(p)), FALSE);
7360 }
7361
7362 /*
7363 * image activation may be failed due to policy
7364 * which is unexpected but security framework does not
7365 * approve of exec, kill and return immediately.
7366 */
7367 if (imgp->ip_mac_return != 0) {
7368 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7369 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY, 0, 0);
7370 signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
7371 error = imgp->ip_mac_return;
7372 unexpected_failure = TRUE;
7373 goto done;
7374 }
7375
7376 if (imgp->ip_cs_error != OS_REASON_NULL) {
7377 signature_failure_reason = imgp->ip_cs_error;
7378 imgp->ip_cs_error = OS_REASON_NULL;
7379 error = EACCES;
7380 goto done;
7381 }
7382
7383 /* call the launch constraints hook */
7384 os_reason_t launch_constraint_reason;
7385 if ((error = mac_proc_check_launch_constraints(p, imgp, &launch_constraint_reason)) != 0) {
7386 signature_failure_reason = launch_constraint_reason;
7387 goto done;
7388 }
7389
7390 #if XNU_TARGET_OS_OSX
7391 /* Check for platform passed in spawn attr if iOS binary is being spawned */
7392 if (proc_platform(p) == PLATFORM_IOS) {
7393 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
7394 if (psa == NULL || psa->psa_platform == 0) {
7395 boolean_t no_sandbox_entitled = FALSE;
7396 #if DEBUG || DEVELOPMENT
7397 /*
7398 * Allow iOS binaries to spawn on internal systems
7399 * if no-sandbox entitlement is present of unentitled_ios_sim_launch
7400 * boot-arg set to true
7401 */
7402 if (unentitled_ios_sim_launch) {
7403 no_sandbox_entitled = TRUE;
7404 } else {
7405 no_sandbox_entitled = IOVnodeHasEntitlement(imgp->ip_vp,
7406 (int64_t)imgp->ip_arch_offset, "com.apple.private.security.no-sandbox");
7407 }
7408 #endif /* DEBUG || DEVELOPMENT */
7409 if (!no_sandbox_entitled) {
7410 signature_failure_reason = os_reason_create(OS_REASON_EXEC,
7411 EXEC_EXIT_REASON_WRONG_PLATFORM);
7412 error = EACCES;
7413 goto done;
7414 }
7415 printf("Allowing spawn of iOS binary %s since it has "
7416 "com.apple.private.security.no-sandbox entitlement or unentitled_ios_sim_launch "
7417 "boot-arg set to true\n", p->p_name);
7418 } else if (psa->psa_platform != PLATFORM_IOS) {
7419 /* Simulator binary spawned with wrong platform */
7420 signature_failure_reason = os_reason_create(OS_REASON_EXEC,
7421 EXEC_EXIT_REASON_WRONG_PLATFORM);
7422 error = EACCES;
7423 goto done;
7424 } else {
7425 printf("Allowing spawn of iOS binary %s since correct platform was passed in spawn\n",
7426 p->p_name);
7427 }
7428 }
7429 #endif /* XNU_TARGET_OS_OSX */
7430
7431 /* If the code signature came through the image activation path, we skip the
7432 * taskgated / externally attached path. */
7433 if (imgp->ip_csflags & CS_SIGNED) {
7434 error = 0;
7435 goto done;
7436 }
7437
7438 /* The rest of the code is for signatures that either already have been externally
7439 * attached (likely, but not necessarily by a previous run through the taskgated
7440 * path), or that will now be attached by taskgated. */
7441
7442 kr = task_get_task_access_port(proc_task(p), &port);
7443 if (KERN_SUCCESS != kr || !IPC_PORT_VALID(port)) {
7444 error = 0;
7445 if (require_success) {
7446 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7447 proc_getpid(p), OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT, 0, 0);
7448 signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT);
7449 error = EACCES;
7450 }
7451 goto done;
7452 }
7453
7454 /*
7455 * taskgated returns KERN_SUCCESS if it has completed its work
7456 * and the exec should continue, KERN_FAILURE if the exec should
7457 * fail, or it may error out with different error code in an
7458 * event of mig failure (e.g. process was signalled during the
7459 * rpc call, taskgated died, mig server died etc.).
7460 */
7461
7462 kr = __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(port, proc_getpid(p));
7463 switch (kr) {
7464 case KERN_SUCCESS:
7465 error = 0;
7466 break;
7467 case KERN_FAILURE:
7468 error = EACCES;
7469
7470 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7471 proc_getpid(p), OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG, 0, 0);
7472 signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG);
7473 goto done;
7474 default:
7475 error = EACCES;
7476
7477 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7478 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER, 0, 0);
7479 signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER);
7480 unexpected_failure = TRUE;
7481 goto done;
7482 }
7483
7484 /* Only do this if exec_resettextvp() did not fail */
7485 if (p->p_textvp != NULLVP) {
7486 csb = ubc_cs_blob_get(p->p_textvp, -1, -1, p->p_textoff);
7487
7488 if (csb != NULL) {
7489 /* As the enforcement we can do here is very limited, we only allow things that
7490 * are the only reason why this code path still exists:
7491 * Adhoc signed non-platform binaries without special cs_flags and without any
7492 * entitlements (unrestricted ones still pass AMFI). */
7493 if (
7494 /* Revalidate the blob if necessary through bumped generation count. */
7495 (ubc_cs_generation_check(p->p_textvp) == 0 ||
7496 ubc_cs_blob_revalidate(p->p_textvp, csb, imgp, 0, proc_platform(p)) == 0) &&
7497 /* Only CS_ADHOC, no CS_KILL, CS_HARD etc. */
7498 (csb->csb_flags & CS_ALLOWED_MACHO) == CS_ADHOC &&
7499 /* If it has a CMS blob, it's not adhoc. The CS_ADHOC flag can lie. */
7500 csblob_find_blob_bytes((const uint8_t *)csb->csb_mem_kaddr, csb->csb_mem_size,
7501 CSSLOT_SIGNATURESLOT,
7502 CSMAGIC_BLOBWRAPPER) == NULL &&
7503 /* It could still be in a trust cache (unlikely with CS_ADHOC), or a magic path. */
7504 csb->csb_platform_binary == 0 &&
7505 /* No entitlements, not even unrestricted ones. */
7506 csb->csb_entitlements_blob == NULL &&
7507 csb->csb_der_entitlements_blob == NULL) {
7508 proc_lock(p);
7509 proc_csflags_set(p, CS_SIGNED | CS_VALID);
7510 proc_unlock(p);
7511 } else {
7512 uint8_t cdhash[CS_CDHASH_LEN];
7513 char cdhash_string[CS_CDHASH_STRING_SIZE];
7514 proc_getcdhash(p, cdhash);
7515 cdhash_to_string(cdhash_string, cdhash);
7516 printf("ignoring detached code signature on '%s' with cdhash '%s' "
7517 "because it is invalid, or not a simple adhoc signature.\n",
7518 p->p_name, cdhash_string);
7519 }
7520 }
7521 }
7522
7523 done:
7524 if (0 == error) {
7525 /*
7526 * Update the new process's signature-dependent process state.
7527 * state.
7528 */
7529
7530 error = proc_process_signature(p, &signature_failure_reason);
7531 }
7532
7533 if (0 == error) {
7534 /*
7535 * Update the new main thread's signature-dependent thread
7536 * state. This was also called when the thread was created,
7537 * but for the main thread the signature was not yet attached
7538 * at that time.
7539 */
7540 kr = thread_process_signature(imgp->ip_new_thread, proc_get_task_raw(p));
7541
7542 if (kr != KERN_SUCCESS) {
7543 error = EINVAL;
7544 signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MACHINE_THREAD);
7545 }
7546 }
7547
7548 if (0 == error) {
7549 /* The process's code signature related properties are
7550 * fully set up, so this is an opportune moment to log
7551 * platform binary execution, if desired. */
7552 if (platform_exec_logging != 0 && csproc_get_platform_binary(p)) {
7553 uint8_t cdhash[CS_CDHASH_LEN];
7554 char cdhash_string[CS_CDHASH_STRING_SIZE];
7555 proc_getcdhash(p, cdhash);
7556 cdhash_to_string(cdhash_string, cdhash);
7557
7558 os_log(peLog, "CS Platform Exec Logging: Executing platform signed binary "
7559 "'%s' with cdhash %s\n", p->p_name, cdhash_string);
7560 }
7561 } else {
7562 if (!unexpected_failure) {
7563 proc_csflags_set(p, CS_KILLED);
7564 }
7565 /* make very sure execution fails */
7566 if (vfexec || spawn) {
7567 assert(signature_failure_reason != OS_REASON_NULL);
7568 psignal_vfork_with_reason(p, proc_task(p), imgp->ip_new_thread,
7569 SIGKILL, signature_failure_reason);
7570 signature_failure_reason = OS_REASON_NULL;
7571 error = 0;
7572 } else {
7573 assert(signature_failure_reason != OS_REASON_NULL);
7574 psignal_with_reason(p, SIGKILL, signature_failure_reason);
7575 signature_failure_reason = OS_REASON_NULL;
7576 }
7577 }
7578
7579 if (port != IPC_PORT_NULL) {
7580 ipc_port_release_send(port);
7581 }
7582
7583 /* If we hit this, we likely would have leaked an exit reason */
7584 assert(signature_failure_reason == OS_REASON_NULL);
7585 return error;
7586 }
7587
7588 /*
7589 * Typically as soon as we start executing this process, the
7590 * first instruction will trigger a VM fault to bring the text
7591 * pages (as executable) into the address space, followed soon
7592 * thereafter by dyld data structures (for dynamic executable).
7593 * To optimize this, as well as improve support for hardware
7594 * debuggers that can only access resident pages present
7595 * in the process' page tables, we prefault some pages if
7596 * possible. Errors are non-fatal.
7597 */
7598 #ifndef PREVENT_CALLER_STACK_USE
7599 #define PREVENT_CALLER_STACK_USE __attribute__((noinline))
7600 #endif
7601 static void PREVENT_CALLER_STACK_USE
exec_prefault_data(proc_t p __unused,struct image_params * imgp,load_result_t * load_result)7602 exec_prefault_data(proc_t p __unused, struct image_params *imgp, load_result_t *load_result)
7603 {
7604 int ret;
7605 size_t expected_all_image_infos_size;
7606 kern_return_t kr;
7607
7608 /*
7609 * Prefault executable or dyld entry point.
7610 */
7611 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7612 DEBUG4K_LOAD("entry_point 0x%llx\n", (uint64_t)load_result->entry_point);
7613 }
7614 kr = vm_fault(current_map(),
7615 vm_map_trunc_page(load_result->entry_point,
7616 vm_map_page_mask(current_map())),
7617 VM_PROT_READ | VM_PROT_EXECUTE,
7618 FALSE, VM_KERN_MEMORY_NONE,
7619 THREAD_UNINT, NULL, 0);
7620 if (kr != KERN_SUCCESS) {
7621 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);
7622 }
7623
7624 if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
7625 expected_all_image_infos_size = sizeof(struct user64_dyld_all_image_infos);
7626 } else {
7627 expected_all_image_infos_size = sizeof(struct user32_dyld_all_image_infos);
7628 }
7629
7630 /* Decode dyld anchor structure from <mach-o/dyld_images.h> */
7631 if (load_result->dynlinker &&
7632 load_result->all_image_info_addr &&
7633 load_result->all_image_info_size >= expected_all_image_infos_size) {
7634 union {
7635 struct user64_dyld_all_image_infos infos64;
7636 struct user32_dyld_all_image_infos infos32;
7637 } all_image_infos;
7638
7639 /*
7640 * Pre-fault to avoid copyin() going through the trap handler
7641 * and recovery path.
7642 */
7643 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7644 DEBUG4K_LOAD("all_image_info_addr 0x%llx\n", load_result->all_image_info_addr);
7645 }
7646 kr = vm_fault(current_map(),
7647 vm_map_trunc_page(load_result->all_image_info_addr,
7648 vm_map_page_mask(current_map())),
7649 VM_PROT_READ | VM_PROT_WRITE,
7650 FALSE, VM_KERN_MEMORY_NONE,
7651 THREAD_UNINT, NULL, 0);
7652 if (kr != KERN_SUCCESS) {
7653 // 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);
7654 }
7655 if ((load_result->all_image_info_addr & PAGE_MASK) + expected_all_image_infos_size > PAGE_SIZE) {
7656 /* all_image_infos straddles a page */
7657 kr = vm_fault(current_map(),
7658 vm_map_trunc_page(load_result->all_image_info_addr + expected_all_image_infos_size - 1,
7659 vm_map_page_mask(current_map())),
7660 VM_PROT_READ | VM_PROT_WRITE,
7661 FALSE, VM_KERN_MEMORY_NONE,
7662 THREAD_UNINT, NULL, 0);
7663 if (kr != KERN_SUCCESS) {
7664 // 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);
7665 }
7666 }
7667
7668 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7669 DEBUG4K_LOAD("copyin(0x%llx, 0x%lx)\n", load_result->all_image_info_addr, expected_all_image_infos_size);
7670 }
7671 ret = copyin((user_addr_t)load_result->all_image_info_addr,
7672 &all_image_infos,
7673 expected_all_image_infos_size);
7674 if (ret == 0 && all_image_infos.infos32.version >= DYLD_ALL_IMAGE_INFOS_ADDRESS_MINIMUM_VERSION) {
7675 user_addr_t notification_address;
7676 user_addr_t dyld_image_address;
7677 user_addr_t dyld_version_address;
7678 user_addr_t dyld_all_image_infos_address;
7679 user_addr_t dyld_slide_amount;
7680
7681 if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
7682 notification_address = (user_addr_t)all_image_infos.infos64.notification;
7683 dyld_image_address = (user_addr_t)all_image_infos.infos64.dyldImageLoadAddress;
7684 dyld_version_address = (user_addr_t)all_image_infos.infos64.dyldVersion;
7685 dyld_all_image_infos_address = (user_addr_t)all_image_infos.infos64.dyldAllImageInfosAddress;
7686 } else {
7687 notification_address = all_image_infos.infos32.notification;
7688 dyld_image_address = all_image_infos.infos32.dyldImageLoadAddress;
7689 dyld_version_address = all_image_infos.infos32.dyldVersion;
7690 dyld_all_image_infos_address = all_image_infos.infos32.dyldAllImageInfosAddress;
7691 }
7692
7693 /*
7694 * dyld statically sets up the all_image_infos in its Mach-O
7695 * binary at static link time, with pointers relative to its default
7696 * load address. Since ASLR might slide dyld before its first
7697 * instruction is executed, "dyld_slide_amount" tells us how far
7698 * dyld was loaded compared to its default expected load address.
7699 * All other pointers into dyld's image should be adjusted by this
7700 * amount. At some point later, dyld will fix up pointers to take
7701 * into account the slide, at which point the all_image_infos_address
7702 * field in the structure will match the runtime load address, and
7703 * "dyld_slide_amount" will be 0, if we were to consult it again.
7704 */
7705
7706 dyld_slide_amount = (user_addr_t)load_result->all_image_info_addr - dyld_all_image_infos_address;
7707
7708 #if 0
7709 kprintf("exec_prefault: 0x%016llx 0x%08x 0x%016llx 0x%016llx 0x%016llx 0x%016llx\n",
7710 (uint64_t)load_result->all_image_info_addr,
7711 all_image_infos.infos32.version,
7712 (uint64_t)notification_address,
7713 (uint64_t)dyld_image_address,
7714 (uint64_t)dyld_version_address,
7715 (uint64_t)dyld_all_image_infos_address);
7716 #endif
7717
7718 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7719 DEBUG4K_LOAD("notification_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)notification_address, (uint64_t)dyld_slide_amount);
7720 }
7721 kr = vm_fault(current_map(),
7722 vm_map_trunc_page(notification_address + dyld_slide_amount,
7723 vm_map_page_mask(current_map())),
7724 VM_PROT_READ | VM_PROT_EXECUTE,
7725 FALSE, VM_KERN_MEMORY_NONE,
7726 THREAD_UNINT, NULL, 0);
7727 if (kr != KERN_SUCCESS) {
7728 // 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);
7729 }
7730 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7731 DEBUG4K_LOAD("dyld_image_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)dyld_image_address, (uint64_t)dyld_slide_amount);
7732 }
7733 kr = vm_fault(current_map(),
7734 vm_map_trunc_page(dyld_image_address + dyld_slide_amount,
7735 vm_map_page_mask(current_map())),
7736 VM_PROT_READ | VM_PROT_EXECUTE,
7737 FALSE, VM_KERN_MEMORY_NONE,
7738 THREAD_UNINT, NULL, 0);
7739 if (kr != KERN_SUCCESS) {
7740 // 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);
7741 }
7742 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7743 DEBUG4K_LOAD("dyld_version_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)dyld_version_address, (uint64_t)dyld_slide_amount);
7744 }
7745 kr = vm_fault(current_map(),
7746 vm_map_trunc_page(dyld_version_address + dyld_slide_amount,
7747 vm_map_page_mask(current_map())),
7748 VM_PROT_READ,
7749 FALSE, VM_KERN_MEMORY_NONE,
7750 THREAD_UNINT, NULL, 0);
7751 if (kr != KERN_SUCCESS) {
7752 // 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);
7753 }
7754 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7755 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);
7756 }
7757 kr = vm_fault(current_map(),
7758 vm_map_trunc_page(dyld_all_image_infos_address + dyld_slide_amount,
7759 vm_map_page_mask(current_map())),
7760 VM_PROT_READ | VM_PROT_WRITE,
7761 FALSE, VM_KERN_MEMORY_NONE,
7762 THREAD_UNINT, NULL, 0);
7763 if (kr != KERN_SUCCESS) {
7764 // 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);
7765 }
7766 }
7767 }
7768 }
7769
7770 static int
7771 sysctl_libmalloc_experiments SYSCTL_HANDLER_ARGS
7772 {
7773 #pragma unused(oidp, arg2, req)
7774 int changed;
7775 errno_t error;
7776 uint64_t value = os_atomic_load_wide(&libmalloc_experiment_factors, relaxed);
7777
7778 error = sysctl_io_number(req, value, sizeof(value), &value, &changed);
7779 if (error) {
7780 return error;
7781 }
7782
7783 if (changed) {
7784 os_atomic_store_wide(&libmalloc_experiment_factors, value, relaxed);
7785 }
7786
7787 return 0;
7788 }
7789
7790 EXPERIMENT_FACTOR_PROC(_kern, libmalloc_experiments, CTLTYPE_QUAD | CTLFLAG_RW, 0, 0, &sysctl_libmalloc_experiments, "A", "");
7791
7792