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
183 #include "kern_exec_internal.h"
184
185 extern boolean_t vm_darkwake_mode;
186
187 /* enable crash reports on various exec failures */
188 static TUNABLE(bool, bootarg_execfailurereports, "execfailurecrashes", false);
189
190 #if XNU_TARGET_OS_OSX
191 #if __has_feature(ptrauth_calls)
192 static TUNABLE(bool, bootarg_arm64e_preview_abi, "-arm64e_preview_abi", false);
193 #endif /* __has_feature(ptrauth_calls) */
194
195 #if DEBUG || DEVELOPMENT
196 static TUNABLE(bool, unentitled_ios_sim_launch, "unentitled_ios_sim_launch", false);
197 #endif /* DEBUG || DEVELOPMENT */
198 #endif /* XNU_TARGET_OS_OSX */
199
200 #if CONFIG_DTRACE
201 /* Do not include dtrace.h, it redefines kmem_[alloc/free] */
202 extern void dtrace_proc_exec(proc_t);
203 extern void (*dtrace_proc_waitfor_exec_ptr)(proc_t);
204
205 /*
206 * Since dtrace_proc_waitfor_exec_ptr can be added/removed in dtrace_subr.c,
207 * we will store its value before actually calling it.
208 */
209 static void (*dtrace_proc_waitfor_hook)(proc_t) = NULL;
210
211 #include <sys/dtrace_ptss.h>
212 #endif
213
214 #if __has_feature(ptrauth_calls)
215 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_per_team_id,
216 "vm_shared_region_per_team_id", 1);
217 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_by_entitlement,
218 "vm_shared_region_by_entitlement", 1);
219
220 /* Upon userland request, reslide the shared cache. */
221 static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_aslr,
222 "vm_shared_region_reslide_aslr",
223 #if CONFIG_RESLIDE_SHARED_CACHE
224 1
225 #else
226 0
227 #endif /* CONFIG_RESLIDE_SHARED_CACHE */
228 );
229
230 /*
231 * Flag to control what processes should get shared cache randomize resliding
232 * after a fault in the shared cache region:
233 *
234 * 0 - all processes get a new randomized slide
235 * 1 - only platform processes get a new randomized slide
236 */
237 TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_restrict,
238 "vm_shared_region_reslide_restrict", 1);
239
240 #if DEVELOPMENT || DEBUG
241 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_per_team_id,
242 CTLFLAG_RW, &vm_shared_region_per_team_id, 0, "");
243 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_by_entitlement,
244 CTLFLAG_RW, &vm_shared_region_by_entitlement, 0, "");
245 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_restrict,
246 CTLFLAG_RW, &vm_shared_region_reslide_restrict, 0, "");
247 SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_aslr,
248 CTLFLAG_RW, &vm_shared_region_reslide_aslr, 0, "");
249 #endif
250 #endif /* __has_feature(ptrauth_calls) */
251
252 #if DEVELOPMENT || DEBUG
253 static TUNABLE(bool, enable_dext_coredumps_on_panic, "dext_panic_coredump", true);
254 #else
255 static TUNABLE(bool, enable_dext_coredumps_on_panic, "dext_panic_coredump", false);
256 #endif
257 extern kern_return_t kern_register_userspace_coredump(task_t task, const char * name);
258 #define USERSPACE_COREDUMP_PANIC_ENTITLEMENT "com.apple.private.enable-coredump-on-panic"
259 #define USERSPACE_COREDUMP_PANIC_SEED_ENTITLEMENT \
260 "com.apple.private.enable-coredump-on-panic-seed-privacy-approved"
261
262 extern void proc_apply_task_networkbg_internal(proc_t, thread_t);
263 extern void task_set_did_exec_flag(task_t task);
264 extern void task_clear_exec_copy_flag(task_t task);
265 proc_t proc_exec_switch_task(proc_t old_proc, proc_t new_proc, task_t old_task,
266 task_t new_task, thread_t new_thread, void **inherit);
267 boolean_t task_is_active(task_t);
268 boolean_t thread_is_active(thread_t thread);
269 void thread_copy_resource_info(thread_t dst_thread, thread_t src_thread);
270 void *ipc_importance_exec_switch_task(task_t old_task, task_t new_task);
271 extern void ipc_importance_release(void *elem);
272 extern boolean_t task_has_watchports(task_t task);
273 extern void task_set_no_smt(task_t task);
274 #if defined(HAS_APPLE_PAC)
275 char *task_get_vm_shared_region_id_and_jop_pid(task_t task, uint64_t *jop_pid);
276 #endif
277 task_t convert_port_to_task(ipc_port_t port);
278
279 /*
280 * Mach things for which prototypes are unavailable from Mach headers
281 */
282 #define IPC_OBJECT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND 0x1
283 void ipc_task_enable(
284 task_t task);
285 void ipc_task_reset(
286 task_t task);
287 void ipc_thread_reset(
288 thread_t thread);
289 kern_return_t ipc_object_copyin(
290 ipc_space_t space,
291 mach_port_name_t name,
292 mach_msg_type_name_t msgt_name,
293 ipc_object_t *objectp,
294 mach_port_context_t context,
295 mach_msg_guard_flags_t *guard_flags,
296 uint32_t kmsg_flags);
297 void ipc_port_release_send(ipc_port_t);
298
299 #if DEVELOPMENT || DEBUG
300 void task_importance_update_owner_info(task_t);
301 #endif
302
303 extern struct savearea *get_user_regs(thread_t);
304
305 __attribute__((noinline)) int __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid);
306
307 #include <kern/thread.h>
308 #include <kern/task.h>
309 #include <kern/ast.h>
310 #include <kern/mach_loader.h>
311 #include <kern/mach_fat.h>
312 #include <mach-o/fat.h>
313 #include <mach-o/loader.h>
314 #include <machine/vmparam.h>
315 #include <sys/imgact.h>
316
317 #include <sys/sdt.h>
318
319
320 /*
321 * EAI_ITERLIMIT The maximum number of times to iterate an image
322 * activator in exec_activate_image() before treating
323 * it as malformed/corrupt.
324 */
325 #define EAI_ITERLIMIT 3
326
327 /*
328 * For #! interpreter parsing
329 */
330 #define IS_WHITESPACE(ch) ((ch == ' ') || (ch == '\t'))
331 #define IS_EOL(ch) ((ch == '#') || (ch == '\n'))
332
333 extern vm_map_t bsd_pageable_map;
334 extern const struct fileops vnops;
335 extern int nextpidversion;
336
337
338 #define USER_ADDR_ALIGN(addr, val) \
339 ( ( (user_addr_t)(addr) + (val) - 1) \
340 & ~((val) - 1) )
341
342 /*
343 * For subsystem root support
344 */
345 #define SPAWN_SUBSYSTEM_ROOT_ENTITLEMENT "com.apple.private.spawn-subsystem-root"
346
347 /*
348 * Allow setting p_crash_behavior to trigger panic on crash
349 */
350 #define SPAWN_SET_PANIC_CRASH_BEHAVIOR "com.apple.private.spawn-panic-crash-behavior"
351
352 /* Platform Code Exec Logging */
353 static int platform_exec_logging = 0;
354
355 SYSCTL_DECL(_security_mac);
356
357 SYSCTL_INT(_security_mac, OID_AUTO, platform_exec_logging, CTLFLAG_RW, &platform_exec_logging, 0,
358 "log cdhashes for all platform binary executions");
359
360 static os_log_t peLog = OS_LOG_DEFAULT;
361
362 struct exec_port_actions {
363 uint32_t portwatch_count;
364 uint32_t registered_count;
365 ipc_port_t *portwatch_array;
366 ipc_port_t *registered_array;
367 };
368
369 struct image_params; /* Forward */
370 static int exec_activate_image(struct image_params *imgp);
371 static int exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp);
372 static int load_return_to_errno(load_return_t lrtn);
373 static int execargs_alloc(struct image_params *imgp);
374 static int execargs_free(struct image_params *imgp);
375 static int exec_check_permissions(struct image_params *imgp);
376 static int exec_extract_strings(struct image_params *imgp);
377 static int exec_add_apple_strings(struct image_params *imgp, const load_result_t *load_result);
378 static int exec_handle_sugid(struct image_params *imgp);
379 static int sugid_scripts = 0;
380 SYSCTL_INT(_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW | CTLFLAG_LOCKED, &sugid_scripts, 0, "");
381 static kern_return_t create_unix_stack(vm_map_t map, load_result_t* load_result, proc_t p);
382 static int copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size);
383 static void exec_resettextvp(proc_t, struct image_params *);
384 static int process_signature(proc_t, struct image_params *);
385 static void exec_prefault_data(proc_t, struct image_params *, load_result_t *);
386 static errno_t exec_handle_port_actions(struct image_params *imgp,
387 struct exec_port_actions *port_actions);
388 static errno_t exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
389 task_role_t psa_darwin_role, struct exec_port_actions *port_actions);
390 static void exec_port_actions_destroy(struct exec_port_actions *port_actions);
391
392 /*
393 * exec_add_user_string
394 *
395 * Add the requested string to the string space area.
396 *
397 * Parameters; struct image_params * image parameter block
398 * user_addr_t string to add to strings area
399 * int segment from which string comes
400 * boolean_t TRUE if string contributes to NCARGS
401 *
402 * Returns: 0 Success
403 * !0 Failure errno from copyinstr()
404 *
405 * Implicit returns:
406 * (imgp->ip_strendp) updated location of next add, if any
407 * (imgp->ip_strspace) updated byte count of space remaining
408 * (imgp->ip_argspace) updated byte count of space in NCARGS
409 */
410 __attribute__((noinline))
411 static int
exec_add_user_string(struct image_params * imgp,user_addr_t str,int seg,boolean_t is_ncargs)412 exec_add_user_string(struct image_params *imgp, user_addr_t str, int seg, boolean_t is_ncargs)
413 {
414 int error = 0;
415
416 do {
417 size_t len = 0;
418 int space;
419
420 if (is_ncargs) {
421 space = imgp->ip_argspace; /* by definition smaller than ip_strspace */
422 } else {
423 space = imgp->ip_strspace;
424 }
425
426 if (space <= 0) {
427 error = E2BIG;
428 break;
429 }
430
431 if (!UIO_SEG_IS_USER_SPACE(seg)) {
432 char *kstr = CAST_DOWN(char *, str); /* SAFE */
433 error = copystr(kstr, imgp->ip_strendp, space, &len);
434 } else {
435 error = copyinstr(str, imgp->ip_strendp, space, &len);
436 }
437
438 imgp->ip_strendp += len;
439 imgp->ip_strspace -= len;
440 if (is_ncargs) {
441 imgp->ip_argspace -= len;
442 }
443 } while (error == ENAMETOOLONG);
444
445 return error;
446 }
447
448 /*
449 * dyld is now passed the executable path as a getenv-like variable
450 * in the same fashion as the stack_guard and malloc_entropy keys.
451 */
452 #define EXECUTABLE_KEY "executable_path="
453
454 /*
455 * exec_save_path
456 *
457 * To support new app package launching for Mac OS X, the dyld needs the
458 * first argument to execve() stored on the user stack.
459 *
460 * Save the executable path name at the bottom of the strings area and set
461 * the argument vector pointer to the location following that to indicate
462 * the start of the argument and environment tuples, setting the remaining
463 * string space count to the size of the string area minus the path length.
464 *
465 * Parameters; struct image_params * image parameter block
466 * char * path used to invoke program
467 * int segment from which path comes
468 *
469 * Returns: int 0 Success
470 * EFAULT Bad address
471 * copy[in]str:EFAULT Bad address
472 * copy[in]str:ENAMETOOLONG Filename too long
473 *
474 * Implicit returns:
475 * (imgp->ip_strings) saved path
476 * (imgp->ip_strspace) space remaining in ip_strings
477 * (imgp->ip_strendp) start of remaining copy area
478 * (imgp->ip_argspace) space remaining of NCARGS
479 * (imgp->ip_applec) Initial applev[0]
480 *
481 * Note: We have to do this before the initial namei() since in the
482 * path contains symbolic links, namei() will overwrite the
483 * original path buffer contents. If the last symbolic link
484 * resolved was a relative pathname, we would lose the original
485 * "path", which could be an absolute pathname. This might be
486 * unacceptable for dyld.
487 */
488 static int
exec_save_path(struct image_params * imgp,user_addr_t path,int seg,const char ** excpath)489 exec_save_path(struct image_params *imgp, user_addr_t path, int seg, const char **excpath)
490 {
491 int error;
492 size_t len;
493 char *kpath;
494
495 // imgp->ip_strings can come out of a cache, so we need to obliterate the
496 // old path.
497 memset(imgp->ip_strings, '\0', strlen(EXECUTABLE_KEY) + MAXPATHLEN);
498
499 len = MIN(MAXPATHLEN, imgp->ip_strspace);
500
501 switch (seg) {
502 case UIO_USERSPACE32:
503 case UIO_USERSPACE64: /* Same for copyin()... */
504 error = copyinstr(path, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
505 break;
506 case UIO_SYSSPACE:
507 kpath = CAST_DOWN(char *, path); /* SAFE */
508 error = copystr(kpath, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
509 break;
510 default:
511 error = EFAULT;
512 break;
513 }
514
515 if (!error) {
516 bcopy(EXECUTABLE_KEY, imgp->ip_strings, strlen(EXECUTABLE_KEY));
517 len += strlen(EXECUTABLE_KEY);
518
519 imgp->ip_strendp += len;
520 imgp->ip_strspace -= len;
521
522 if (excpath) {
523 *excpath = imgp->ip_strings + strlen(EXECUTABLE_KEY);
524 }
525 }
526
527 return error;
528 }
529
530 /*
531 * exec_reset_save_path
532 *
533 * If we detect a shell script, we need to reset the string area
534 * state so that the interpreter can be saved onto the stack.
535 *
536 * Parameters; struct image_params * image parameter block
537 *
538 * Returns: int 0 Success
539 *
540 * Implicit returns:
541 * (imgp->ip_strings) saved path
542 * (imgp->ip_strspace) space remaining in ip_strings
543 * (imgp->ip_strendp) start of remaining copy area
544 * (imgp->ip_argspace) space remaining of NCARGS
545 *
546 */
547 static int
exec_reset_save_path(struct image_params * imgp)548 exec_reset_save_path(struct image_params *imgp)
549 {
550 imgp->ip_strendp = imgp->ip_strings;
551 imgp->ip_argspace = NCARGS;
552 imgp->ip_strspace = (NCARGS + PAGE_SIZE);
553
554 return 0;
555 }
556
557 /*
558 * exec_shell_imgact
559 *
560 * Image activator for interpreter scripts. If the image begins with
561 * the characters "#!", then it is an interpreter script. Verify the
562 * length of the script line indicating the interpreter is not in
563 * excess of the maximum allowed size. If this is the case, then
564 * break out the arguments, if any, which are separated by white
565 * space, and copy them into the argument save area as if they were
566 * provided on the command line before all other arguments. The line
567 * ends when we encounter a comment character ('#') or newline.
568 *
569 * Parameters; struct image_params * image parameter block
570 *
571 * Returns: -1 not an interpreter (keep looking)
572 * -3 Success: interpreter: relookup
573 * >0 Failure: interpreter: error number
574 *
575 * A return value other than -1 indicates subsequent image activators should
576 * not be given the opportunity to attempt to activate the image.
577 */
578 static int
exec_shell_imgact(struct image_params * imgp)579 exec_shell_imgact(struct image_params *imgp)
580 {
581 char *vdata = imgp->ip_vdata;
582 char *ihp;
583 char *line_startp, *line_endp;
584 char *interp;
585
586 /*
587 * Make sure it's a shell script. If we've already redirected
588 * from an interpreted file once, don't do it again.
589 */
590 if (vdata[0] != '#' ||
591 vdata[1] != '!' ||
592 (imgp->ip_flags & IMGPF_INTERPRET) != 0) {
593 return -1;
594 }
595
596 if (imgp->ip_origcputype != 0) {
597 /* Fat header previously matched, don't allow shell script inside */
598 return -1;
599 }
600
601 imgp->ip_flags |= IMGPF_INTERPRET;
602 imgp->ip_interp_sugid_fd = -1;
603 imgp->ip_interp_buffer[0] = '\0';
604
605 /* Check to see if SUGID scripts are permitted. If they aren't then
606 * clear the SUGID bits.
607 * imgp->ip_vattr is known to be valid.
608 */
609 if (sugid_scripts == 0) {
610 imgp->ip_origvattr->va_mode &= ~(VSUID | VSGID);
611 }
612
613 /* Try to find the first non-whitespace character */
614 for (ihp = &vdata[2]; ihp < &vdata[IMG_SHSIZE]; ihp++) {
615 if (IS_EOL(*ihp)) {
616 /* Did not find interpreter, "#!\n" */
617 return ENOEXEC;
618 } else if (IS_WHITESPACE(*ihp)) {
619 /* Whitespace, like "#! /bin/sh\n", keep going. */
620 } else {
621 /* Found start of interpreter */
622 break;
623 }
624 }
625
626 if (ihp == &vdata[IMG_SHSIZE]) {
627 /* All whitespace, like "#! " */
628 return ENOEXEC;
629 }
630
631 line_startp = ihp;
632
633 /* Try to find the end of the interpreter+args string */
634 for (; ihp < &vdata[IMG_SHSIZE]; ihp++) {
635 if (IS_EOL(*ihp)) {
636 /* Got it */
637 break;
638 } else {
639 /* Still part of interpreter or args */
640 }
641 }
642
643 if (ihp == &vdata[IMG_SHSIZE]) {
644 /* A long line, like "#! blah blah blah" without end */
645 return ENOEXEC;
646 }
647
648 /* Backtrack until we find the last non-whitespace */
649 while (IS_EOL(*ihp) || IS_WHITESPACE(*ihp)) {
650 ihp--;
651 }
652
653 /* The character after the last non-whitespace is our logical end of line */
654 line_endp = ihp + 1;
655
656 /*
657 * Now we have pointers to the usable part of:
658 *
659 * "#! /usr/bin/int first second third \n"
660 * ^ line_startp ^ line_endp
661 */
662
663 /* copy the interpreter name */
664 interp = imgp->ip_interp_buffer;
665 for (ihp = line_startp; (ihp < line_endp) && !IS_WHITESPACE(*ihp); ihp++) {
666 *interp++ = *ihp;
667 }
668 *interp = '\0';
669
670 exec_reset_save_path(imgp);
671 exec_save_path(imgp, CAST_USER_ADDR_T(imgp->ip_interp_buffer),
672 UIO_SYSSPACE, NULL);
673
674 /* Copy the entire interpreter + args for later processing into argv[] */
675 interp = imgp->ip_interp_buffer;
676 for (ihp = line_startp; (ihp < line_endp); ihp++) {
677 *interp++ = *ihp;
678 }
679 *interp = '\0';
680
681 #if CONFIG_SETUID
682 /*
683 * If we have an SUID or SGID script, create a file descriptor
684 * from the vnode and pass /dev/fd/%d instead of the actual
685 * path name so that the script does not get opened twice
686 */
687 if (imgp->ip_origvattr->va_mode & (VSUID | VSGID)) {
688 proc_t p;
689 struct fileproc *fp;
690 int fd;
691 int error;
692
693 p = vfs_context_proc(imgp->ip_vfs_context);
694 error = falloc(p, &fp, &fd, imgp->ip_vfs_context);
695 if (error) {
696 return error;
697 }
698
699 fp->fp_glob->fg_flag = FREAD;
700 fp->fp_glob->fg_ops = &vnops;
701 fp_set_data(fp, imgp->ip_vp);
702
703 proc_fdlock(p);
704 procfdtbl_releasefd(p, fd, NULL);
705 fp_drop(p, fd, fp, 1);
706 proc_fdunlock(p);
707 vnode_ref(imgp->ip_vp);
708
709 imgp->ip_interp_sugid_fd = fd;
710 }
711 #endif /* CONFIG_SETUID */
712
713 return -3;
714 }
715
716
717
718 /*
719 * exec_fat_imgact
720 *
721 * Image activator for fat 1.0 binaries. If the binary is fat, then we
722 * need to select an image from it internally, and make that the image
723 * we are going to attempt to execute. At present, this consists of
724 * reloading the first page for the image with a first page from the
725 * offset location indicated by the fat header.
726 *
727 * Parameters; struct image_params * image parameter block
728 *
729 * Returns: -1 not a fat binary (keep looking)
730 * -2 Success: encapsulated binary: reread
731 * >0 Failure: error number
732 *
733 * Important: This image activator is byte order neutral.
734 *
735 * Note: A return value other than -1 indicates subsequent image
736 * activators should not be given the opportunity to attempt
737 * to activate the image.
738 *
739 * If we find an encapsulated binary, we make no assertions
740 * about its validity; instead, we leave that up to a rescan
741 * for an activator to claim it, and, if it is claimed by one,
742 * that activator is responsible for determining validity.
743 */
744 static int
exec_fat_imgact(struct image_params * imgp)745 exec_fat_imgact(struct image_params *imgp)
746 {
747 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
748 kauth_cred_t cred = kauth_cred_proc_ref(p);
749 struct fat_header *fat_header = (struct fat_header *)imgp->ip_vdata;
750 struct _posix_spawnattr *psa = NULL;
751 struct fat_arch fat_arch;
752 int resid, error;
753 load_return_t lret;
754
755 if (imgp->ip_origcputype != 0) {
756 /* Fat header previously matched, don't allow another fat file inside */
757 error = -1; /* not claimed */
758 goto bad;
759 }
760
761 /* Make sure it's a fat binary */
762 if (OSSwapBigToHostInt32(fat_header->magic) != FAT_MAGIC) {
763 error = -1; /* not claimed */
764 goto bad;
765 }
766
767 /* imgp->ip_vdata has PAGE_SIZE, zerofilled if the file is smaller */
768 lret = fatfile_validate_fatarches((vm_offset_t)fat_header, PAGE_SIZE,
769 (off_t)imgp->ip_vattr->va_data_size);
770 if (lret != LOAD_SUCCESS) {
771 error = load_return_to_errno(lret);
772 goto bad;
773 }
774
775 /* If posix_spawn binprefs exist, respect those prefs. */
776 psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
777 if (psa != NULL && psa->psa_binprefs[0] != 0) {
778 uint32_t pr = 0;
779
780 /* Check each preference listed against all arches in header */
781 for (pr = 0; pr < NBINPREFS; pr++) {
782 cpu_type_t pref = psa->psa_binprefs[pr];
783 cpu_type_t subpref = psa->psa_subcpuprefs[pr];
784
785 if (pref == 0) {
786 /* No suitable arch in the pref list */
787 error = EBADARCH;
788 goto bad;
789 }
790
791 if (pref == CPU_TYPE_ANY) {
792 /* Fall through to regular grading */
793 goto regular_grading;
794 }
795
796 lret = fatfile_getbestarch_for_cputype(pref,
797 subpref,
798 (vm_offset_t)fat_header,
799 PAGE_SIZE,
800 imgp,
801 &fat_arch);
802 if (lret == LOAD_SUCCESS) {
803 goto use_arch;
804 }
805 }
806
807 /* Requested binary preference was not honored */
808 error = EBADEXEC;
809 goto bad;
810 }
811
812 regular_grading:
813 /* Look up our preferred architecture in the fat file. */
814 lret = fatfile_getbestarch((vm_offset_t)fat_header,
815 PAGE_SIZE,
816 imgp,
817 &fat_arch,
818 (p->p_flag & P_AFFINITY) != 0);
819 if (lret != LOAD_SUCCESS) {
820 error = load_return_to_errno(lret);
821 goto bad;
822 }
823
824 use_arch:
825 /* Read the Mach-O header out of fat_arch */
826 error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata,
827 PAGE_SIZE, fat_arch.offset,
828 UIO_SYSSPACE, (IO_UNIT | IO_NODELOCKED),
829 cred, &resid, p);
830 if (error) {
831 goto bad;
832 }
833
834 if (resid) {
835 memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
836 }
837
838 /* Success. Indicate we have identified an encapsulated binary */
839 error = -2;
840 imgp->ip_arch_offset = (user_size_t)fat_arch.offset;
841 imgp->ip_arch_size = (user_size_t)fat_arch.size;
842 imgp->ip_origcputype = fat_arch.cputype;
843 imgp->ip_origcpusubtype = fat_arch.cpusubtype;
844
845 bad:
846 kauth_cred_unref(&cred);
847 return error;
848 }
849
850 static int
activate_exec_state(task_t task,proc_t p,thread_t thread,load_result_t * result)851 activate_exec_state(task_t task, proc_t p, thread_t thread, load_result_t *result)
852 {
853 int ret;
854
855 (void)task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0);
856 task_set_64bit(task, result->is_64bit_addr, result->is_64bit_data);
857 if (result->is_64bit_addr) {
858 OSBitOrAtomic(P_LP64, &p->p_flag);
859 get_bsdthread_info(thread)->uu_flag |= UT_LP64;
860 } else {
861 OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag);
862 get_bsdthread_info(thread)->uu_flag &= ~UT_LP64;
863 }
864 task_set_mach_header_address(task, result->mach_header);
865
866 ret = thread_state_initialize(thread);
867 if (ret != KERN_SUCCESS) {
868 return ret;
869 }
870
871 if (result->threadstate) {
872 uint32_t *ts = result->threadstate;
873 uint32_t total_size = (uint32_t)result->threadstate_sz;
874
875 while (total_size > 0) {
876 uint32_t flavor = *ts++;
877 uint32_t size = *ts++;
878
879 ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
880 if (ret) {
881 return ret;
882 }
883 ts += size;
884 total_size -= (size + 2) * sizeof(uint32_t);
885 }
886 }
887
888 thread_setentrypoint(thread, result->entry_point);
889
890 return KERN_SUCCESS;
891 }
892
893 #if (DEVELOPMENT || DEBUG)
894 extern char panic_on_proc_crash[];
895 extern int use_panic_on_proc_crash;
896
897 extern char panic_on_proc_exit[];
898 extern int use_panic_on_proc_exit;
899
900 extern char panic_on_proc_spawn_fail[];
901 extern int use_panic_on_proc_spawn_fail;
902 #endif
903
904 void
set_proc_name(struct image_params * imgp,proc_t p)905 set_proc_name(struct image_params *imgp, proc_t p)
906 {
907 int p_name_len = sizeof(p->p_name) - 1;
908
909 if (imgp->ip_ndp->ni_cnd.cn_namelen > p_name_len) {
910 imgp->ip_ndp->ni_cnd.cn_namelen = p_name_len;
911 }
912
913 bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_name,
914 (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
915 p->p_name[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
916
917 if (imgp->ip_ndp->ni_cnd.cn_namelen > MAXCOMLEN) {
918 imgp->ip_ndp->ni_cnd.cn_namelen = MAXCOMLEN;
919 }
920
921 bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_comm,
922 (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
923 p->p_comm[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
924
925 #if DEVELOPMENT || DEBUG
926 /*
927 * This happens during image activation, so the crash behavior flags from
928 * posix_spawn will have already been set. So we don't have to worry about
929 * this being overridden.
930 */
931 if (use_panic_on_proc_crash && strcmp(p->p_comm, panic_on_proc_crash) == 0) {
932 printf("will panic on proc crash: %s\n", p->p_comm);
933 p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_CRASH;
934 }
935
936 if (use_panic_on_proc_exit && strcmp(p->p_comm, panic_on_proc_exit) == 0) {
937 printf("will panic on proc exit: %s\n", p->p_comm);
938 p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_EXIT;
939 }
940
941 if (use_panic_on_proc_spawn_fail && strcmp(p->p_comm, panic_on_proc_spawn_fail) == 0) {
942 printf("will panic on proc spawn fail: %s\n", p->p_comm);
943 p->p_crash_behavior |= POSIX_SPAWN_PANIC_ON_SPAWN_FAIL;
944 }
945 #endif
946 }
947
948 #if __has_feature(ptrauth_calls)
949 /**
950 * Returns a team ID string that may be used to assign a shared region.
951 *
952 * Platform binaries do not have team IDs and will return NULL. Non-platform
953 * binaries without a team ID will be assigned an artificial team ID of ""
954 * (empty string) so that they will not be assigned to the default shared
955 * region.
956 *
957 * @param imgp image parameter block
958 * @return NULL if this is a platform binary, or an appropriate team ID string
959 * otherwise
960 */
961 static inline const char *
get_teamid_for_shared_region(struct image_params * imgp)962 get_teamid_for_shared_region(struct image_params *imgp)
963 {
964 assert(imgp->ip_vp != NULL);
965
966 const char *ret = csvnode_get_teamid(imgp->ip_vp, imgp->ip_arch_offset);
967 if (ret) {
968 return ret;
969 }
970
971 struct cs_blob *blob = csvnode_get_blob(imgp->ip_vp, imgp->ip_arch_offset);
972 if (csblob_get_platform_binary(blob)) {
973 return NULL;
974 } else {
975 static const char *NO_TEAM_ID = "";
976 return NO_TEAM_ID;
977 }
978 }
979
980 /**
981 * Determines whether ptrauth should be enabled for the provided arm64 CPU subtype.
982 *
983 * @param cpusubtype Mach-O style CPU subtype
984 * @return whether the CPU subtype matches arm64e with the current ptrauth ABI
985 */
986 static inline bool
arm64_cpusubtype_uses_ptrauth(cpu_subtype_t cpusubtype)987 arm64_cpusubtype_uses_ptrauth(cpu_subtype_t cpusubtype)
988 {
989 return (cpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
990 CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(cpusubtype) == CPU_SUBTYPE_ARM64_PTR_AUTH_CURRENT_VERSION;
991 }
992
993 #endif /* __has_feature(ptrauth_calls) */
994
995 /**
996 * Returns whether a type/subtype slice matches the requested
997 * type/subtype.
998 *
999 * @param mask Bits to mask from the requested/tested cpu type
1000 * @param req_cpu Requested cpu type
1001 * @param req_subcpu Requested cpu subtype
1002 * @param test_cpu Tested slice cpu type
1003 * @param test_subcpu Tested slice cpu subtype
1004 */
1005 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)1006 binary_match(cpu_type_t mask, cpu_type_t req_cpu,
1007 cpu_subtype_t req_subcpu, cpu_type_t test_cpu,
1008 cpu_subtype_t test_subcpu)
1009 {
1010 if ((test_cpu & ~mask) != (req_cpu & ~mask)) {
1011 return FALSE;
1012 }
1013
1014 test_subcpu &= ~CPU_SUBTYPE_MASK;
1015 req_subcpu &= ~CPU_SUBTYPE_MASK;
1016
1017 if (test_subcpu != req_subcpu && req_subcpu != (CPU_SUBTYPE_ANY & ~CPU_SUBTYPE_MASK)) {
1018 return FALSE;
1019 }
1020
1021 return TRUE;
1022 }
1023
1024
1025 #define MIN_IOS_TPRO_SDK_VERSION 0x00100000
1026 #define MIN_OSX_TPRO_SDK_VERSION 0x000D0000
1027 #define MIN_TVOS_TPRO_SDK_VERSION 0x000D0000
1028 #define MIN_WATCHOS_TPRO_SDK_VERSION 0x00090000
1029 #define MIN_DRIVERKIT_TPRO_SDK_VERSION 0x00600000
1030
1031 static void
exec_setup_tpro(struct image_params * imgp,load_result_t * load_result)1032 exec_setup_tpro(struct image_params *imgp, load_result_t *load_result)
1033 {
1034 extern boolean_t xprr_tpro_enabled;
1035 extern boolean_t enable_user_modifiable_perms;
1036 uint32_t min_sdk_version = 0;
1037
1038 /* x86-64 translated code cannot take advantage of TPRO */
1039 if (imgp->ip_flags & IMGPF_ROSETTA) {
1040 return;
1041 }
1042
1043 /* Do not enable on 32-bit VA targets */
1044 if (!(imgp->ip_flags & IMGPF_IS_64BIT_ADDR)) {
1045 return;
1046 }
1047
1048 switch (load_result->ip_platform) {
1049 case PLATFORM_IOS:
1050 case PLATFORM_IOSSIMULATOR:
1051 case PLATFORM_MACCATALYST:
1052 min_sdk_version = MIN_IOS_TPRO_SDK_VERSION;
1053 break;
1054 case PLATFORM_MACOS:
1055 min_sdk_version = MIN_OSX_TPRO_SDK_VERSION;
1056 break;
1057 case PLATFORM_TVOS:
1058 case PLATFORM_TVOSSIMULATOR:
1059 min_sdk_version = MIN_TVOS_TPRO_SDK_VERSION;
1060 break;
1061 case PLATFORM_WATCHOS:
1062 case PLATFORM_WATCHOSSIMULATOR:
1063 min_sdk_version = MIN_WATCHOS_TPRO_SDK_VERSION;
1064 break;
1065 case PLATFORM_DRIVERKIT:
1066 min_sdk_version = MIN_DRIVERKIT_TPRO_SDK_VERSION;
1067 break;
1068 default:
1069 /* TPRO is on by default for newer platforms */
1070 break;
1071 }
1072
1073 }
1074
1075 /*
1076 * If the passed in executable's vnode should use the RSR
1077 * shared region, then this should return TRUE, otherwise, return FALSE.
1078 */
1079 static uint32_t rsr_current_version = 0;
1080 boolean_t (*rsr_check_vnode)(void *vnode) = NULL;
1081
1082 boolean_t
vnode_is_rsr(vnode_t vp)1083 vnode_is_rsr(vnode_t vp)
1084 {
1085 if (!(vnode_isreg(vp) && vnode_tag(vp) == VT_APFS)) {
1086 return FALSE;
1087 }
1088
1089 if (rsr_check_vnode != NULL && rsr_check_vnode((void *)vp)) {
1090 return TRUE;
1091 }
1092 return FALSE;
1093 }
1094
1095
1096 uint32_t
rsr_get_version(void)1097 rsr_get_version(void)
1098 {
1099 return os_atomic_load(&rsr_current_version, relaxed);
1100 }
1101
1102 void
rsr_bump_version(void)1103 rsr_bump_version(void)
1104 {
1105 os_atomic_inc(&rsr_current_version, relaxed);
1106 }
1107
1108 #if XNU_TARGET_OS_OSX
1109 static int
1110 rsr_version_sysctl SYSCTL_HANDLER_ARGS
1111 {
1112 #pragma unused(arg1, arg2, oidp)
1113 int value = rsr_get_version();
1114 int error = SYSCTL_OUT(req, &value, sizeof(int));
1115 if (error) {
1116 return error;
1117 }
1118
1119 if (!req->newptr) {
1120 return 0;
1121 }
1122
1123 error = SYSCTL_IN(req, &value, sizeof(int));
1124 if (error) {
1125 return error;
1126 }
1127 if (value != 0) {
1128 rsr_bump_version();
1129 }
1130 return 0;
1131 }
1132
1133
1134 SYSCTL_PROC(_vm, OID_AUTO, shared_region_control,
1135 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_MASKED,
1136 0, 0, rsr_version_sysctl, "I", "");
1137 #endif /* XNU_TARGET_OS_OSX */
1138
1139 /*
1140 * exec_mach_imgact
1141 *
1142 * Image activator for mach-o 1.0 binaries.
1143 *
1144 * Parameters; struct image_params * image parameter block
1145 *
1146 * Returns: -1 not a fat binary (keep looking)
1147 * -2 Success: encapsulated binary: reread
1148 * >0 Failure: error number
1149 * EBADARCH Mach-o binary, but with an unrecognized
1150 * architecture
1151 * ENOMEM No memory for child process after -
1152 * can only happen after vfork()
1153 *
1154 * Important: This image activator is NOT byte order neutral.
1155 *
1156 * Note: A return value other than -1 indicates subsequent image
1157 * activators should not be given the opportunity to attempt
1158 * to activate the image.
1159 */
1160 static int
exec_mach_imgact(struct image_params * imgp)1161 exec_mach_imgact(struct image_params *imgp)
1162 {
1163 struct mach_header *mach_header = (struct mach_header *)imgp->ip_vdata;
1164 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
1165 int error = 0;
1166 task_t task;
1167 task_t new_task = NULL; /* protected by vfexec */
1168 thread_t thread;
1169 struct uthread *uthread;
1170 vm_map_t old_map = VM_MAP_NULL;
1171 vm_map_t map = VM_MAP_NULL;
1172 load_return_t lret;
1173 load_result_t load_result = {};
1174 struct _posix_spawnattr *psa = NULL;
1175 int spawn = (imgp->ip_flags & IMGPF_SPAWN);
1176 const int vfexec = 0;
1177 int exec = (imgp->ip_flags & IMGPF_EXEC);
1178 os_reason_t exec_failure_reason = OS_REASON_NULL;
1179 boolean_t reslide = FALSE;
1180 char * userspace_coredump_name = NULL;
1181
1182 /*
1183 * make sure it's a Mach-O 1.0 or Mach-O 2.0 binary; the difference
1184 * is a reserved field on the end, so for the most part, we can
1185 * treat them as if they were identical. Reverse-endian Mach-O
1186 * binaries are recognized but not compatible.
1187 */
1188 if ((mach_header->magic == MH_CIGAM) ||
1189 (mach_header->magic == MH_CIGAM_64)) {
1190 error = EBADARCH;
1191 goto bad;
1192 }
1193
1194 if ((mach_header->magic != MH_MAGIC) &&
1195 (mach_header->magic != MH_MAGIC_64)) {
1196 error = -1;
1197 goto bad;
1198 }
1199
1200 if (mach_header->filetype != MH_EXECUTE) {
1201 error = -1;
1202 goto bad;
1203 }
1204
1205 if (imgp->ip_origcputype != 0) {
1206 /* Fat header previously had an idea about this thin file */
1207 if (imgp->ip_origcputype != mach_header->cputype ||
1208 imgp->ip_origcpusubtype != mach_header->cpusubtype) {
1209 error = EBADARCH;
1210 goto bad;
1211 }
1212 } else {
1213 imgp->ip_origcputype = mach_header->cputype;
1214 imgp->ip_origcpusubtype = mach_header->cpusubtype;
1215 }
1216
1217 task = current_task();
1218 thread = current_thread();
1219 uthread = get_bsdthread_info(thread);
1220
1221 if ((mach_header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64) {
1222 imgp->ip_flags |= IMGPF_IS_64BIT_ADDR | IMGPF_IS_64BIT_DATA;
1223 }
1224
1225
1226 /* If posix_spawn binprefs exist, respect those prefs. */
1227 psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
1228 if (psa != NULL && psa->psa_binprefs[0] != 0) {
1229 int pr = 0;
1230 for (pr = 0; pr < NBINPREFS; pr++) {
1231 cpu_type_t pref = psa->psa_binprefs[pr];
1232 cpu_subtype_t subpref = psa->psa_subcpuprefs[pr];
1233
1234 if (pref == 0) {
1235 /* No suitable arch in the pref list */
1236 error = EBADARCH;
1237 goto bad;
1238 }
1239
1240 if (pref == CPU_TYPE_ANY) {
1241 /* Jump to regular grading */
1242 goto grade;
1243 }
1244
1245 if (binary_match(CPU_ARCH_MASK, pref, subpref,
1246 imgp->ip_origcputype, imgp->ip_origcpusubtype)) {
1247 goto grade;
1248 }
1249 }
1250 error = EBADARCH;
1251 goto bad;
1252 }
1253 grade:
1254 if (!grade_binary(imgp->ip_origcputype, imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK,
1255 imgp->ip_origcpusubtype & CPU_SUBTYPE_MASK, TRUE)) {
1256 error = EBADARCH;
1257 goto bad;
1258 }
1259
1260 if (validate_potential_simulator_binary(imgp->ip_origcputype, imgp,
1261 imgp->ip_arch_offset, imgp->ip_arch_size) != LOAD_SUCCESS) {
1262 #if __x86_64__
1263 const char *excpath;
1264 error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
1265 os_log_error(OS_LOG_DEFAULT, "Unsupported 32-bit executable: \"%s\"", (error) ? imgp->ip_vp->v_name : excpath);
1266 #endif
1267 error = EBADARCH;
1268 goto bad;
1269 }
1270
1271 #if defined(HAS_APPLE_PAC)
1272 assert(mach_header->cputype == CPU_TYPE_ARM64
1273 );
1274
1275 if ((mach_header->cputype == CPU_TYPE_ARM64 &&
1276 arm64_cpusubtype_uses_ptrauth(mach_header->cpusubtype))
1277 ) {
1278 imgp->ip_flags &= ~IMGPF_NOJOP;
1279 } else {
1280 imgp->ip_flags |= IMGPF_NOJOP;
1281 }
1282 #endif
1283
1284 /* Copy in arguments/environment from the old process */
1285 error = exec_extract_strings(imgp);
1286 if (error) {
1287 goto bad;
1288 }
1289
1290 AUDIT_ARG(argv, imgp->ip_startargv, imgp->ip_argc,
1291 imgp->ip_endargv - imgp->ip_startargv);
1292 AUDIT_ARG(envv, imgp->ip_endargv, imgp->ip_envc,
1293 imgp->ip_endenvv - imgp->ip_endargv);
1294
1295
1296
1297 /* reset local idea of thread, uthread, task */
1298 thread = imgp->ip_new_thread;
1299 uthread = get_bsdthread_info(thread);
1300 task = new_task = get_threadtask(thread);
1301
1302 /*
1303 * Load the Mach-O file.
1304 *
1305 * NOTE: An error after this point indicates we have potentially
1306 * destroyed or overwritten some process state while attempting an
1307 * execve() following a vfork(), which is an unrecoverable condition.
1308 * We send the new process an immediate SIGKILL to avoid it executing
1309 * any instructions in the mutated address space. For true spawns,
1310 * this is not the case, and "too late" is still not too late to
1311 * return an error code to the parent process.
1312 */
1313
1314 /*
1315 * Actually load the image file we previously decided to load.
1316 */
1317 lret = load_machfile(imgp, mach_header, thread, &map, &load_result);
1318 if (lret != LOAD_SUCCESS) {
1319 error = load_return_to_errno(lret);
1320
1321 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1322 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO, 0, 0);
1323 if (lret == LOAD_BADMACHO_UPX) {
1324 set_proc_name(imgp, p);
1325 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_UPX);
1326 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1327 } else {
1328 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1329
1330 if (bootarg_execfailurereports) {
1331 set_proc_name(imgp, p);
1332 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1333 }
1334 }
1335
1336 exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1337
1338 goto badtoolate;
1339 }
1340
1341 /*
1342 * ERROR RECOVERY
1343 *
1344 * load_machfile() returned the new VM map ("map") but we haven't
1345 * committed to it yet.
1346 * Any error path between here and the point where we commit to using
1347 * the new "map" (with swap_task_map()) should deallocate "map".
1348 */
1349
1350 #ifndef KASAN
1351 /*
1352 * Security: zone sanity checks on fresh boot or initproc re-exec.
1353 * launchd by design does not tear down its own service port on USR (rdar://72797967),
1354 * which means here is the earliest point we can assert on empty service port label zone,
1355 * after load_machfile() above terminates old launchd's IPC space.
1356 *
1357 * Disable on KASAN builds since zone_size_allocated() accounts for elements
1358 * under quarantine.
1359 */
1360 if (task_pid(task) == 1) {
1361 zone_userspace_reboot_checks();
1362 }
1363 #endif
1364
1365 proc_lock(p);
1366 p->p_cputype = imgp->ip_origcputype;
1367 p->p_cpusubtype = imgp->ip_origcpusubtype;
1368 proc_setplatformdata(p, load_result.ip_platform, load_result.lr_min_sdk, load_result.lr_sdk);
1369 exec_setup_tpro(imgp, &load_result);
1370
1371 vm_map_set_size_limit(map, proc_limitgetcur(p, RLIMIT_AS));
1372 vm_map_set_data_limit(map, proc_limitgetcur(p, RLIMIT_DATA));
1373 vm_map_set_user_wire_limit(map, (vm_size_t)proc_limitgetcur(p, RLIMIT_MEMLOCK));
1374 #if XNU_TARGET_OS_OSX
1375 if (proc_platform(p) == PLATFORM_IOS) {
1376 assert(vm_map_is_alien(map));
1377 } else {
1378 assert(!vm_map_is_alien(map));
1379 }
1380 #endif /* XNU_TARGET_OS_OSX */
1381 proc_unlock(p);
1382
1383 /*
1384 * Set code-signing flags if this binary is signed, or if parent has
1385 * requested them on exec.
1386 */
1387 if (load_result.csflags & CS_VALID) {
1388 imgp->ip_csflags |= load_result.csflags &
1389 (CS_VALID | CS_SIGNED | CS_DEV_CODE | CS_LINKER_SIGNED |
1390 CS_HARD | CS_KILL | CS_RESTRICT | CS_ENFORCEMENT | CS_REQUIRE_LV |
1391 CS_FORCED_LV | CS_ENTITLEMENTS_VALIDATED | CS_NO_UNTRUSTED_HELPERS | CS_RUNTIME |
1392 CS_ENTITLEMENT_FLAGS |
1393 CS_EXEC_SET_HARD | CS_EXEC_SET_KILL | CS_EXEC_SET_ENFORCEMENT);
1394 } else {
1395 imgp->ip_csflags &= ~CS_VALID;
1396 }
1397
1398 if (proc_getcsflags(p) & CS_EXEC_SET_HARD) {
1399 imgp->ip_csflags |= CS_HARD;
1400 }
1401 if (proc_getcsflags(p) & CS_EXEC_SET_KILL) {
1402 imgp->ip_csflags |= CS_KILL;
1403 }
1404 if (proc_getcsflags(p) & CS_EXEC_SET_ENFORCEMENT) {
1405 imgp->ip_csflags |= CS_ENFORCEMENT;
1406 }
1407 if (proc_getcsflags(p) & CS_EXEC_INHERIT_SIP) {
1408 if (proc_getcsflags(p) & CS_INSTALLER) {
1409 imgp->ip_csflags |= CS_INSTALLER;
1410 }
1411 if (proc_getcsflags(p) & CS_DATAVAULT_CONTROLLER) {
1412 imgp->ip_csflags |= CS_DATAVAULT_CONTROLLER;
1413 }
1414 if (proc_getcsflags(p) & CS_NVRAM_UNRESTRICTED) {
1415 imgp->ip_csflags |= CS_NVRAM_UNRESTRICTED;
1416 }
1417 }
1418
1419 #if __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX)
1420 /*
1421 * ptrauth version 0 is a preview ABI. Developers can opt into running
1422 * their own arm64e binaries for local testing, with the understanding
1423 * that future OSes may break ABI.
1424 */
1425 if ((imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
1426 CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(imgp->ip_origcpusubtype) == 0 &&
1427 !load_result.platform_binary &&
1428 !bootarg_arm64e_preview_abi) {
1429 static bool logged_once = false;
1430 set_proc_name(imgp, p);
1431
1432 printf("%s: not running binary \"%s\" built against preview arm64e ABI\n", __func__, p->p_name);
1433 if (!os_atomic_xchg(&logged_once, true, relaxed)) {
1434 printf("%s: (to allow this, add \"-arm64e_preview_abi\" to boot-args)\n", __func__);
1435 }
1436
1437 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1438 if (bootarg_execfailurereports) {
1439 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1440 exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1441 }
1442
1443 /* release new address space since we won't use it */
1444 vm_map_deallocate(map);
1445 map = VM_MAP_NULL;
1446 goto badtoolate;
1447 }
1448
1449 if ((imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) != CPU_SUBTYPE_ARM64E &&
1450 imgp->ip_origcputype == CPU_TYPE_ARM64 &&
1451 load_result.platform_binary &&
1452 (imgp->ip_flags & IMGPF_DRIVER) != 0) {
1453 set_proc_name(imgp, p);
1454 printf("%s: disallowing arm64 platform driverkit binary \"%s\", should be arm64e\n", __func__, p->p_name);
1455 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO);
1456 if (bootarg_execfailurereports) {
1457 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1458 exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE;
1459 }
1460
1461 /* release new address space since we won't use it */
1462 vm_map_deallocate(map);
1463 map = VM_MAP_NULL;
1464 goto badtoolate;
1465 }
1466 #endif /* __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX) */
1467
1468
1469 /*
1470 * Set up the shared cache region in the new process.
1471 *
1472 * Normally there is a single shared region per architecture.
1473 * However on systems with Pointer Authentication, we can create
1474 * multiple shared caches with the amount of sharing determined
1475 * by team-id or entitlement. Inherited shared region IDs are used
1476 * for system processes that need to match and be able to inspect
1477 * a pre-existing task.
1478 */
1479 int cpu_subtype = 0; /* all cpu_subtypes use the same shared region */
1480 #if __has_feature(ptrauth_calls)
1481 char *shared_region_id = NULL;
1482 size_t len;
1483 char *base;
1484 const char *cbase;
1485 #define TEAM_ID_PREFIX "T-"
1486 #define ENTITLE_PREFIX "E-"
1487 #define SR_PREFIX_LEN 2
1488 #define SR_ENTITLEMENT "com.apple.pac.shared_region_id"
1489
1490 if (cpu_type() == CPU_TYPE_ARM64 &&
1491 arm64_cpusubtype_uses_ptrauth(p->p_cpusubtype) &&
1492 (imgp->ip_flags & IMGPF_NOJOP) == 0) {
1493 assertf(p->p_cputype == CPU_TYPE_ARM64,
1494 "p %p cpu_type() 0x%x p->p_cputype 0x%x p->p_cpusubtype 0x%x",
1495 p, cpu_type(), p->p_cputype, p->p_cpusubtype);
1496
1497 /*
1498 * arm64e uses pointer authentication, so request a separate
1499 * shared region for this CPU subtype.
1500 */
1501 cpu_subtype = p->p_cpusubtype & ~CPU_SUBTYPE_MASK;
1502
1503 /*
1504 * Determine which shared cache to select based on being told,
1505 * matching a team-id or matching an entitlement.
1506 */
1507 if (imgp->ip_inherited_shared_region_id) {
1508 len = strlen(imgp->ip_inherited_shared_region_id);
1509 shared_region_id = kalloc_data(len + 1, Z_WAITOK | Z_NOFAIL);
1510 memcpy(shared_region_id, imgp->ip_inherited_shared_region_id, len + 1);
1511 } else if ((cbase = get_teamid_for_shared_region(imgp)) != NULL) {
1512 len = strlen(cbase);
1513 if (vm_shared_region_per_team_id) {
1514 shared_region_id = kalloc_data(len + SR_PREFIX_LEN + 1,
1515 Z_WAITOK | Z_NOFAIL);
1516 memcpy(shared_region_id, TEAM_ID_PREFIX, SR_PREFIX_LEN);
1517 memcpy(shared_region_id + SR_PREFIX_LEN, cbase, len + 1);
1518 }
1519 } else if ((base = IOVnodeGetEntitlement(imgp->ip_vp,
1520 (int64_t)imgp->ip_arch_offset, SR_ENTITLEMENT)) != NULL) {
1521 len = strlen(base);
1522 if (vm_shared_region_by_entitlement) {
1523 shared_region_id = kalloc_data(len + SR_PREFIX_LEN + 1,
1524 Z_WAITOK | Z_NOFAIL);
1525 memcpy(shared_region_id, ENTITLE_PREFIX, SR_PREFIX_LEN);
1526 memcpy(shared_region_id + SR_PREFIX_LEN, base, len + 1);
1527 }
1528 /* Discard the copy of the entitlement */
1529 kfree_data(base, len + 1);
1530 }
1531 }
1532
1533 if (imgp->ip_flags & IMGPF_RESLIDE) {
1534 reslide = TRUE;
1535 }
1536
1537 /* use "" as the default shared_region_id */
1538 if (shared_region_id == NULL) {
1539 shared_region_id = kalloc_data(1, Z_WAITOK | Z_ZERO | Z_NOFAIL);
1540 }
1541
1542 /* ensure there's a unique pointer signing key for this shared_region_id */
1543 shared_region_key_alloc(shared_region_id,
1544 imgp->ip_inherited_shared_region_id != NULL, imgp->ip_inherited_jop_pid);
1545 task_set_shared_region_id(task, shared_region_id);
1546 shared_region_id = NULL;
1547 #endif /* __has_feature(ptrauth_calls) */
1548
1549 #if CONFIG_ROSETTA
1550 if (imgp->ip_flags & IMGPF_ROSETTA) {
1551 OSBitOrAtomic(P_TRANSLATED, &p->p_flag);
1552 } else if (p->p_flag & P_TRANSLATED) {
1553 OSBitAndAtomic(~P_TRANSLATED, &p->p_flag);
1554 }
1555 #endif
1556
1557 int cputype = cpu_type();
1558
1559 uint32_t rsr_version = 0;
1560 #if XNU_TARGET_OS_OSX
1561 if (vnode_is_rsr(imgp->ip_vp)) {
1562 rsr_version = rsr_get_version();
1563 os_atomic_or(&p->p_ladvflag, P_RSR, relaxed);
1564 os_atomic_or(&p->p_vfs_iopolicy, P_VFS_IOPOLICY_ALTLINK, relaxed);
1565 }
1566 #endif /* XNU_TARGET_OS_OSX */
1567
1568 vm_map_exec(map, task, load_result.is_64bit_addr,
1569 (void *)p->p_fd.fd_rdir, cputype, cpu_subtype, reslide,
1570 (imgp->ip_flags & IMGPF_DRIVER) != 0,
1571 rsr_version);
1572
1573 /*
1574 * Close file descriptors which specify close-on-exec.
1575 */
1576 fdt_exec(p, psa != NULL ? psa->psa_flags : 0, imgp->ip_new_thread, exec);
1577
1578 /*
1579 * deal with set[ug]id.
1580 */
1581 error = exec_handle_sugid(imgp);
1582 if (error) {
1583 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1584 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE, 0, 0);
1585
1586 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE);
1587 if (bootarg_execfailurereports) {
1588 set_proc_name(imgp, p);
1589 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1590 }
1591
1592 /* release new address space since we won't use it */
1593 vm_map_deallocate(map);
1594 map = VM_MAP_NULL;
1595 goto badtoolate;
1596 }
1597
1598 /*
1599 * Commit to new map.
1600 *
1601 * Swap the new map for the old for target task, which consumes
1602 * our new map reference but each leaves us responsible for the
1603 * old_map reference. That lets us get off the pmap associated
1604 * with it, and then we can release it.
1605 *
1606 * The map needs to be set on the target task which is different
1607 * than current task, thus swap_task_map is used instead of
1608 * vm_map_switch.
1609 */
1610 old_map = swap_task_map(task, thread, map);
1611 #if MACH_ASSERT
1612 /*
1613 * Reset the pmap's process info to prevent ledger checks
1614 * which might fail due to the ledgers being shared between
1615 * the old and new pmaps.
1616 */
1617 vm_map_pmap_set_process(old_map, -1, "<old_map>");
1618 #endif /* MACH_ASSERT */
1619 vm_map_deallocate(old_map);
1620 old_map = NULL;
1621
1622 lret = activate_exec_state(task, p, thread, &load_result);
1623 if (lret != KERN_SUCCESS) {
1624 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1625 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE, 0, 0);
1626
1627 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE);
1628 if (bootarg_execfailurereports) {
1629 set_proc_name(imgp, p);
1630 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1631 }
1632
1633 goto badtoolate;
1634 }
1635
1636 /*
1637 * deal with voucher on exec-calling thread.
1638 */
1639 if (imgp->ip_new_thread == NULL) {
1640 thread_set_mach_voucher(current_thread(), IPC_VOUCHER_NULL);
1641 }
1642
1643 /* Make sure we won't interrupt ourself signalling a partial process */
1644 if (!vfexec && !spawn && (p->p_lflag & P_LTRACED)) {
1645 psignal(p, SIGTRAP);
1646 }
1647
1648 if (load_result.unixproc &&
1649 create_unix_stack(get_task_map(task),
1650 &load_result,
1651 p) != KERN_SUCCESS) {
1652 error = load_return_to_errno(LOAD_NOSPACE);
1653
1654 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1655 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC, 0, 0);
1656
1657 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC);
1658 if (bootarg_execfailurereports) {
1659 set_proc_name(imgp, p);
1660 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1661 }
1662
1663 goto badtoolate;
1664 }
1665
1666 /*
1667 * The load result will have already been munged by AMFI to include the
1668 * platform binary flag if boot-args dictated it (AMFI will mark anything
1669 * that doesn't go through the upcall path as a platform binary if its
1670 * enforcement is disabled).
1671 */
1672 if (load_result.platform_binary) {
1673 if (cs_debug) {
1674 printf("setting platform binary on task: pid = %d\n", proc_getpid(p));
1675 }
1676
1677 /*
1678 * We must use 'task' here because the proc's task has not yet been
1679 * switched to the new one.
1680 */
1681 task_set_platform_binary(task, TRUE);
1682 } else {
1683 if (cs_debug) {
1684 printf("clearing platform binary on task: pid = %d\n", proc_getpid(p));
1685 }
1686
1687 task_set_platform_binary(task, FALSE);
1688 }
1689
1690 /*
1691 * Set starting EXC_GUARD and control port behavior for task now that
1692 * platform is set. Use the name directly from imgp since we haven't
1693 * set_proc_name() yet. Also make control port for the task and main thread
1694 * immovable/pinned based on task's option.
1695 *
1696 * Must happen before main thread port copyout in exc_add_apple_strings.
1697 */
1698 task_set_exc_guard_ctrl_port_default(task, thread,
1699 imgp->ip_ndp->ni_cnd.cn_nameptr,
1700 (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen,
1701 proc_is_simulated(p),
1702 load_result.ip_platform,
1703 load_result.lr_sdk);
1704
1705 error = exec_add_apple_strings(imgp, &load_result); /* copies out main thread port */
1706
1707 if (error) {
1708 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1709 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT, 0, 0);
1710
1711 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT);
1712 if (bootarg_execfailurereports) {
1713 set_proc_name(imgp, p);
1714 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1715 }
1716 goto badtoolate;
1717 }
1718
1719 /* Switch to target task's map to copy out strings */
1720 old_map = vm_map_switch(get_task_map(task));
1721
1722 if (load_result.unixproc) {
1723 user_addr_t ap;
1724
1725 /*
1726 * Copy the strings area out into the new process address
1727 * space.
1728 */
1729 ap = p->user_stack;
1730 error = exec_copyout_strings(imgp, &ap);
1731 if (error) {
1732 vm_map_switch(old_map);
1733
1734 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1735 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS, 0, 0);
1736
1737 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS);
1738 if (bootarg_execfailurereports) {
1739 set_proc_name(imgp, p);
1740 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1741 }
1742 goto badtoolate;
1743 }
1744 /* Set the stack */
1745 thread_setuserstack(thread, ap);
1746 }
1747
1748 if (load_result.dynlinker || load_result.is_rosetta) {
1749 user_addr_t ap;
1750 int new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
1751
1752 /* Adjust the stack */
1753 ap = thread_adjuserstack(thread, -new_ptr_size);
1754 error = copyoutptr(load_result.mach_header, ap, new_ptr_size);
1755
1756 if (error) {
1757 vm_map_switch(old_map);
1758
1759 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1760 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER, 0, 0);
1761
1762 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER);
1763 if (bootarg_execfailurereports) {
1764 set_proc_name(imgp, p);
1765 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1766 }
1767 goto badtoolate;
1768 }
1769 error = task_set_dyld_info(task, load_result.all_image_info_addr,
1770 load_result.all_image_info_size);
1771 if (error) {
1772 vm_map_switch(old_map);
1773
1774 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1775 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO, 0, 0);
1776
1777 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SET_DYLD_INFO);
1778 if (bootarg_execfailurereports) {
1779 set_proc_name(imgp, p);
1780 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1781 }
1782 error = EINVAL;
1783 goto badtoolate;
1784 }
1785 }
1786
1787 #if CONFIG_ROSETTA
1788 if (load_result.is_rosetta) {
1789 // Add an fd for the executable file for Rosetta's use
1790 int main_binary_fd;
1791 struct fileproc *fp;
1792
1793 error = falloc(p, &fp, &main_binary_fd, imgp->ip_vfs_context);
1794 if (error) {
1795 vm_map_switch(old_map);
1796
1797 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1798 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC, 0, 0);
1799
1800 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC);
1801 if (bootarg_execfailurereports) {
1802 set_proc_name(imgp, p);
1803 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1804 }
1805 goto badtoolate;
1806 }
1807
1808 error = VNOP_OPEN(imgp->ip_vp, FREAD, imgp->ip_vfs_context);
1809 if (error) {
1810 vm_map_switch(old_map);
1811
1812 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1813 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC, 0, 0);
1814
1815 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MAIN_FD_ALLOC);
1816 if (bootarg_execfailurereports) {
1817 set_proc_name(imgp, p);
1818 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1819 }
1820 goto cleanup_rosetta_fp;
1821 }
1822
1823 fp->fp_glob->fg_flag = FREAD;
1824 fp->fp_glob->fg_ops = &vnops;
1825 fp_set_data(fp, imgp->ip_vp);
1826
1827 proc_fdlock(p);
1828 procfdtbl_releasefd(p, main_binary_fd, NULL);
1829 fp_drop(p, main_binary_fd, fp, 1);
1830 proc_fdunlock(p);
1831
1832 vnode_ref(imgp->ip_vp);
1833
1834 // Pass the dyld load address, main binary fd, and dyld fd on the stack
1835 uint64_t ap = thread_adjuserstack(thread, -24);
1836
1837 error = copyoutptr((user_addr_t)load_result.dynlinker_fd, ap, 8);
1838 if (error) {
1839 vm_map_switch(old_map);
1840
1841 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1842 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
1843
1844 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
1845 if (bootarg_execfailurereports) {
1846 set_proc_name(imgp, p);
1847 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1848 }
1849 goto cleanup_rosetta_fp;
1850 }
1851
1852 error = copyoutptr(load_result.dynlinker_mach_header, ap + 8, 8);
1853 if (error) {
1854 vm_map_switch(old_map);
1855
1856 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1857 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
1858
1859 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
1860 if (bootarg_execfailurereports) {
1861 set_proc_name(imgp, p);
1862 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1863 }
1864 goto cleanup_rosetta_fp;
1865 }
1866
1867 error = copyoutptr((user_addr_t)main_binary_fd, ap + 16, 8);
1868 if (error) {
1869 vm_map_switch(old_map);
1870
1871 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
1872 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA, 0, 0);
1873
1874 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_ROSETTA);
1875 if (bootarg_execfailurereports) {
1876 set_proc_name(imgp, p);
1877 exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
1878 }
1879 goto cleanup_rosetta_fp;
1880 }
1881
1882 cleanup_rosetta_fp:
1883 if (error) {
1884 fp_free(p, load_result.dynlinker_fd, load_result.dynlinker_fp);
1885 fp_free(p, main_binary_fd, fp);
1886 goto badtoolate;
1887 }
1888 }
1889
1890 #endif
1891
1892 /* Avoid immediate VM faults back into kernel */
1893 exec_prefault_data(p, imgp, &load_result);
1894
1895 vm_map_switch(old_map);
1896
1897 /*
1898 * Reset signal state.
1899 */
1900 execsigs(p, thread);
1901
1902 /*
1903 * need to cancel async IO requests that can be cancelled and wait for those
1904 * already active. MAY BLOCK!
1905 */
1906 _aio_exec( p );
1907
1908 #if SYSV_SHM
1909 /* FIXME: Till vmspace inherit is fixed: */
1910 if (!vfexec && p->vm_shm) {
1911 shmexec(p);
1912 }
1913 #endif
1914 #if SYSV_SEM
1915 /* Clean up the semaphores */
1916 semexit(p);
1917 #endif
1918
1919 /*
1920 * Remember file name for accounting.
1921 */
1922 p->p_acflag &= ~AFORK;
1923
1924 set_proc_name(imgp, p);
1925
1926 #if CONFIG_SECLUDED_MEMORY
1927 if (secluded_for_apps &&
1928 load_result.platform_binary) {
1929 if (strncmp(p->p_name,
1930 "Camera",
1931 sizeof(p->p_name)) == 0) {
1932 task_set_could_use_secluded_mem(task, TRUE);
1933 } else {
1934 task_set_could_use_secluded_mem(task, FALSE);
1935 }
1936 if (strncmp(p->p_name,
1937 "mediaserverd",
1938 sizeof(p->p_name)) == 0) {
1939 task_set_could_also_use_secluded_mem(task, TRUE);
1940 }
1941 }
1942 #endif /* CONFIG_SECLUDED_MEMORY */
1943
1944 #if __arm64__
1945 if (load_result.legacy_footprint) {
1946 task_set_legacy_footprint(task);
1947 }
1948 #endif /* __arm64__ */
1949
1950 pal_dbg_set_task_name(task);
1951
1952 #if DEVELOPMENT || DEBUG
1953 /*
1954 * Update the pid an proc name for importance base if any
1955 */
1956 task_importance_update_owner_info(task);
1957 #endif
1958
1959 proc_setexecutableuuid(p, &load_result.uuid[0]);
1960
1961 #if CONFIG_DTRACE
1962 dtrace_proc_exec(p);
1963 #endif
1964
1965 if (kdebug_enable) {
1966 long args[4] = {};
1967
1968 uintptr_t fsid = 0, fileid = 0;
1969 if (imgp->ip_vattr) {
1970 uint64_t fsid64 = vnode_get_va_fsid(imgp->ip_vattr);
1971 fsid = (uintptr_t)fsid64;
1972 fileid = (uintptr_t)imgp->ip_vattr->va_fileid;
1973 // check for (unexpected) overflow and trace zero in that case
1974 if (fsid != fsid64 || fileid != imgp->ip_vattr->va_fileid) {
1975 fsid = fileid = 0;
1976 }
1977 }
1978 KERNEL_DEBUG_CONSTANT_IST1(TRACE_DATA_EXEC, proc_getpid(p), fsid, fileid, 0,
1979 (uintptr_t)thread_tid(thread));
1980
1981 extern void kdebug_proc_name_args(struct proc *proc, long args[static 4]);
1982 kdebug_proc_name_args(p, args);
1983 KERNEL_DEBUG_CONSTANT_IST1(TRACE_STRING_EXEC, args[0], args[1],
1984 args[2], args[3], (uintptr_t)thread_tid(thread));
1985 }
1986
1987
1988 /*
1989 * If posix_spawned with the START_SUSPENDED flag, stop the
1990 * process before it runs.
1991 */
1992 if (imgp->ip_px_sa != NULL) {
1993 psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
1994 if (psa->psa_flags & POSIX_SPAWN_START_SUSPENDED) {
1995 proc_lock(p);
1996 p->p_stat = SSTOP;
1997 proc_unlock(p);
1998 (void) task_suspend_internal(task);
1999 }
2000 }
2001
2002 /*
2003 * mark as execed
2004 */
2005 OSBitOrAtomic(P_EXEC, &p->p_flag);
2006 proc_resetregister(p);
2007 if (p->p_pptr && (p->p_lflag & P_LPPWAIT)) {
2008 proc_lock(p);
2009 p->p_lflag &= ~P_LPPWAIT;
2010 proc_unlock(p);
2011 wakeup((caddr_t)p->p_pptr);
2012 }
2013
2014 /*
2015 * Set up dext coredumps on kernel panic.
2016 * This requires the following:
2017 * - dext_panic_coredump=1 boot-arg (enabled by default on DEVELOPMENT, DEBUG and certain Seed builds)
2018 * - process must be a driver
2019 * - process must have the com.apple.private.enable-coredump-on-panic entitlement, and the
2020 * entitlement has a string value.
2021 * - process must have the com.apple.private.enable-coredump-on-panic-seed-privacy-approved
2022 * entitlement (Seed builds only).
2023 *
2024 * The core dump file name is formatted with the entitlement string value, followed by a hyphen
2025 * and the process PID.
2026 */
2027 if (enable_dext_coredumps_on_panic &&
2028 (imgp->ip_flags & IMGPF_DRIVER) != 0 &&
2029 (userspace_coredump_name = IOVnodeGetEntitlement(imgp->ip_vp,
2030 (int64_t)imgp->ip_arch_offset, USERSPACE_COREDUMP_PANIC_ENTITLEMENT)) != NULL) {
2031 size_t userspace_coredump_name_len = strlen(userspace_coredump_name);
2032
2033 char core_name[MACH_CORE_FILEHEADER_NAMELEN];
2034 /* 16 - NULL char - strlen("-") - maximum of 5 digits for pid */
2035 snprintf(core_name, MACH_CORE_FILEHEADER_NAMELEN, "%.9s-%d", userspace_coredump_name, proc_getpid(p));
2036
2037 kern_register_userspace_coredump(task, core_name);
2038
2039 /* Discard the copy of the entitlement */
2040 kfree_data(userspace_coredump_name, userspace_coredump_name_len + 1);
2041 userspace_coredump_name = NULL;
2042 }
2043
2044 goto done;
2045
2046 badtoolate:
2047 /* Don't allow child process to execute any instructions */
2048 if (!spawn) {
2049 {
2050 assert(exec_failure_reason != OS_REASON_NULL);
2051 if (bootarg_execfailurereports) {
2052 set_proc_name(imgp, current_proc());
2053 }
2054 psignal_with_reason(current_proc(), SIGKILL, exec_failure_reason);
2055 exec_failure_reason = OS_REASON_NULL;
2056
2057 if (exec) {
2058 /* Terminate the exec copy task */
2059 task_terminate_internal(task);
2060 }
2061 }
2062
2063 /* We can't stop this system call at this point, so just pretend we succeeded */
2064 error = 0;
2065 } else {
2066 os_reason_free(exec_failure_reason);
2067 exec_failure_reason = OS_REASON_NULL;
2068 }
2069
2070 done:
2071 if (load_result.threadstate) {
2072 kfree_data(load_result.threadstate, load_result.threadstate_sz);
2073 load_result.threadstate = NULL;
2074 }
2075
2076 bad:
2077 /* If we hit this, we likely would have leaked an exit reason */
2078 assert(exec_failure_reason == OS_REASON_NULL);
2079 return error;
2080 }
2081
2082
2083
2084
2085 /*
2086 * Our image activator table; this is the table of the image types we are
2087 * capable of loading. We list them in order of preference to ensure the
2088 * fastest image load speed.
2089 *
2090 * XXX hardcoded, for now; should use linker sets
2091 */
2092 struct execsw {
2093 int(*const ex_imgact)(struct image_params *);
2094 const char *ex_name;
2095 }const execsw[] = {
2096 { exec_mach_imgact, "Mach-o Binary" },
2097 { exec_fat_imgact, "Fat Binary" },
2098 { exec_shell_imgact, "Interpreter Script" },
2099 { NULL, NULL}
2100 };
2101
2102
2103 /*
2104 * exec_activate_image
2105 *
2106 * Description: Iterate through the available image activators, and activate
2107 * the image associated with the imgp structure. We start with
2108 * the activator for Mach-o binaries followed by that for Fat binaries
2109 * for Interpreter scripts.
2110 *
2111 * Parameters: struct image_params * Image parameter block
2112 *
2113 * Returns: 0 Success
2114 * ENOEXEC No activator for image.
2115 * EBADEXEC The executable is corrupt/unknown
2116 * execargs_alloc:EINVAL Invalid argument
2117 * execargs_alloc:EACCES Permission denied
2118 * execargs_alloc:EINTR Interrupted function
2119 * execargs_alloc:ENOMEM Not enough space
2120 * exec_save_path:EFAULT Bad address
2121 * exec_save_path:ENAMETOOLONG Filename too long
2122 * exec_check_permissions:EACCES Permission denied
2123 * exec_check_permissions:ENOEXEC Executable file format error
2124 * exec_check_permissions:ETXTBSY Text file busy [misuse of error code]
2125 * exec_check_permissions:???
2126 * namei:???
2127 * vn_rdwr:??? [anything vn_rdwr can return]
2128 * <ex_imgact>:??? [anything an imgact can return]
2129 * EDEADLK Process is being terminated
2130 */
2131 static int
exec_activate_image(struct image_params * imgp)2132 exec_activate_image(struct image_params *imgp)
2133 {
2134 struct nameidata *ndp = NULL;
2135 const char *excpath;
2136 int error;
2137 int resid;
2138 int once = 1; /* save SGUID-ness for interpreted files */
2139 int i;
2140 int itercount = 0;
2141 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2142
2143 /*
2144 * For exec, the translock needs to be taken on old proc and not
2145 * on new shadow proc.
2146 */
2147 if (imgp->ip_flags & IMGPF_EXEC) {
2148 p = current_proc();
2149 }
2150
2151 error = execargs_alloc(imgp);
2152 if (error) {
2153 goto bad_notrans;
2154 }
2155
2156 error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath);
2157 if (error) {
2158 goto bad_notrans;
2159 }
2160
2161 /* Use excpath, which contains the copyin-ed exec path */
2162 DTRACE_PROC1(exec, uintptr_t, excpath);
2163
2164 ndp = kalloc_type(struct nameidata, Z_WAITOK | Z_ZERO | Z_NOFAIL);
2165
2166 NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
2167 UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
2168
2169 again:
2170 error = namei(ndp);
2171 if (error) {
2172 if (error == ERESTART) {
2173 error = EINTR;
2174 }
2175 goto bad_notrans;
2176 }
2177 imgp->ip_ndp = ndp; /* successful namei(); call nameidone() later */
2178 imgp->ip_vp = ndp->ni_vp; /* if set, need to vnode_put() at some point */
2179
2180 /*
2181 * Before we start the transition from binary A to binary B, make
2182 * sure another thread hasn't started exiting the process. We grab
2183 * the proc lock to check p_lflag initially, and the transition
2184 * mechanism ensures that the value doesn't change after we release
2185 * the lock.
2186 */
2187 proc_lock(p);
2188 if (p->p_lflag & P_LEXIT) {
2189 error = EDEADLK;
2190 proc_unlock(p);
2191 goto bad_notrans;
2192 }
2193 error = proc_transstart(p, 1, 0);
2194 proc_unlock(p);
2195 if (error) {
2196 goto bad_notrans;
2197 }
2198
2199 error = exec_check_permissions(imgp);
2200 if (error) {
2201 goto bad;
2202 }
2203
2204 /* Copy; avoid invocation of an interpreter overwriting the original */
2205 if (once) {
2206 once = 0;
2207 *imgp->ip_origvattr = *imgp->ip_vattr;
2208 }
2209
2210 error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata, PAGE_SIZE, 0,
2211 UIO_SYSSPACE, IO_NODELOCKED,
2212 vfs_context_ucred(imgp->ip_vfs_context),
2213 &resid, vfs_context_proc(imgp->ip_vfs_context));
2214 if (error) {
2215 goto bad;
2216 }
2217
2218 if (resid) {
2219 memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
2220 }
2221
2222 encapsulated_binary:
2223 /* Limit the number of iterations we will attempt on each binary */
2224 if (++itercount > EAI_ITERLIMIT) {
2225 error = EBADEXEC;
2226 goto bad;
2227 }
2228 error = -1;
2229 for (i = 0; error == -1 && execsw[i].ex_imgact != NULL; i++) {
2230 error = (*execsw[i].ex_imgact)(imgp);
2231
2232 switch (error) {
2233 /* case -1: not claimed: continue */
2234 case -2: /* Encapsulated binary, imgp->ip_XXX set for next iteration */
2235 goto encapsulated_binary;
2236
2237 case -3: /* Interpreter */
2238 #if CONFIG_MACF
2239 /*
2240 * Copy the script label for later use. Note that
2241 * the label can be different when the script is
2242 * actually read by the interpreter.
2243 */
2244 if (imgp->ip_scriptlabelp) {
2245 mac_vnode_label_free(imgp->ip_scriptlabelp);
2246 imgp->ip_scriptlabelp = NULL;
2247 }
2248 imgp->ip_scriptlabelp = mac_vnode_label_alloc(NULL);
2249 if (imgp->ip_scriptlabelp == NULL) {
2250 error = ENOMEM;
2251 break;
2252 }
2253 mac_vnode_label_copy(mac_vnode_label(imgp->ip_vp),
2254 imgp->ip_scriptlabelp);
2255
2256 /*
2257 * Take a ref of the script vnode for later use.
2258 */
2259 if (imgp->ip_scriptvp) {
2260 vnode_put(imgp->ip_scriptvp);
2261 imgp->ip_scriptvp = NULLVP;
2262 }
2263 if (vnode_getwithref(imgp->ip_vp) == 0) {
2264 imgp->ip_scriptvp = imgp->ip_vp;
2265 }
2266 #endif
2267
2268 nameidone(ndp);
2269
2270 vnode_put(imgp->ip_vp);
2271 imgp->ip_vp = NULL; /* already put */
2272 imgp->ip_ndp = NULL; /* already nameidone */
2273
2274 /* Use excpath, which exec_shell_imgact reset to the interpreter */
2275 NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF,
2276 UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context);
2277
2278 proc_transend(p, 0);
2279 goto again;
2280
2281 default:
2282 break;
2283 }
2284 }
2285
2286 if (error == -1) {
2287 error = ENOEXEC;
2288 } else if (error == 0) {
2289 if (imgp->ip_flags & IMGPF_INTERPRET && ndp->ni_vp) {
2290 AUDIT_ARG(vnpath, ndp->ni_vp, ARG_VNODE2);
2291 }
2292
2293 /*
2294 * Call out to allow 3rd party notification of exec.
2295 * Ignore result of kauth_authorize_fileop call.
2296 */
2297 if (kauth_authorize_fileop_has_listeners()) {
2298 kauth_authorize_fileop(vfs_context_ucred(imgp->ip_vfs_context),
2299 KAUTH_FILEOP_EXEC,
2300 (uintptr_t)ndp->ni_vp, 0);
2301 }
2302 }
2303 bad:
2304 proc_transend(p, 0);
2305
2306 bad_notrans:
2307 if (imgp->ip_strings) {
2308 execargs_free(imgp);
2309 }
2310 if (imgp->ip_ndp) {
2311 nameidone(imgp->ip_ndp);
2312 }
2313 kfree_type(struct nameidata, ndp);
2314
2315 return error;
2316 }
2317
2318 /*
2319 * exec_validate_spawnattr_policy
2320 *
2321 * Description: Validates the entitlements required to set the apptype.
2322 *
2323 * Parameters: int psa_apptype posix spawn attribute apptype
2324 *
2325 * Returns: 0 Success
2326 * EPERM Failure
2327 */
2328 static errno_t
exec_validate_spawnattr_policy(int psa_apptype)2329 exec_validate_spawnattr_policy(int psa_apptype)
2330 {
2331 if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
2332 int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
2333 if (proctype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
2334 if (!IOCurrentTaskHasEntitlement(POSIX_SPAWN_ENTITLEMENT_DRIVER)) {
2335 return EPERM;
2336 }
2337 }
2338 }
2339
2340 return 0;
2341 }
2342
2343 /*
2344 * exec_handle_spawnattr_policy
2345 *
2346 * Description: Decode and apply the posix_spawn apptype, qos clamp, and watchport ports to the task.
2347 *
2348 * Parameters: proc_t p process to apply attributes to
2349 * int psa_apptype posix spawn attribute apptype
2350 *
2351 * Returns: 0 Success
2352 */
2353 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)2354 exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
2355 task_role_t psa_darwin_role, struct exec_port_actions *port_actions)
2356 {
2357 int apptype = TASK_APPTYPE_NONE;
2358 int qos_clamp = THREAD_QOS_UNSPECIFIED;
2359 task_role_t role = TASK_UNSPECIFIED;
2360
2361 if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) {
2362 int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK;
2363
2364 switch (proctype) {
2365 case POSIX_SPAWN_PROC_TYPE_DAEMON_INTERACTIVE:
2366 apptype = TASK_APPTYPE_DAEMON_INTERACTIVE;
2367 break;
2368 case POSIX_SPAWN_PROC_TYPE_DAEMON_STANDARD:
2369 apptype = TASK_APPTYPE_DAEMON_STANDARD;
2370 break;
2371 case POSIX_SPAWN_PROC_TYPE_DAEMON_ADAPTIVE:
2372 apptype = TASK_APPTYPE_DAEMON_ADAPTIVE;
2373 break;
2374 case POSIX_SPAWN_PROC_TYPE_DAEMON_BACKGROUND:
2375 apptype = TASK_APPTYPE_DAEMON_BACKGROUND;
2376 break;
2377 case POSIX_SPAWN_PROC_TYPE_APP_DEFAULT:
2378 apptype = TASK_APPTYPE_APP_DEFAULT;
2379 break;
2380 case POSIX_SPAWN_PROC_TYPE_DRIVER:
2381 apptype = TASK_APPTYPE_DRIVER;
2382 break;
2383 default:
2384 apptype = TASK_APPTYPE_NONE;
2385 /* TODO: Should an invalid value here fail the spawn? */
2386 break;
2387 }
2388 }
2389
2390 if (psa_qos_clamp != POSIX_SPAWN_PROC_CLAMP_NONE) {
2391 switch (psa_qos_clamp) {
2392 case POSIX_SPAWN_PROC_CLAMP_UTILITY:
2393 qos_clamp = THREAD_QOS_UTILITY;
2394 break;
2395 case POSIX_SPAWN_PROC_CLAMP_BACKGROUND:
2396 qos_clamp = THREAD_QOS_BACKGROUND;
2397 break;
2398 case POSIX_SPAWN_PROC_CLAMP_MAINTENANCE:
2399 qos_clamp = THREAD_QOS_MAINTENANCE;
2400 break;
2401 default:
2402 qos_clamp = THREAD_QOS_UNSPECIFIED;
2403 /* TODO: Should an invalid value here fail the spawn? */
2404 break;
2405 }
2406 }
2407
2408 if (psa_darwin_role != PRIO_DARWIN_ROLE_DEFAULT) {
2409 proc_darwin_role_to_task_role(psa_darwin_role, &role);
2410 }
2411
2412 if (apptype != TASK_APPTYPE_NONE ||
2413 qos_clamp != THREAD_QOS_UNSPECIFIED ||
2414 role != TASK_UNSPECIFIED ||
2415 port_actions->portwatch_count) {
2416 proc_set_task_spawnpolicy(proc_task(p), thread, apptype, qos_clamp, role,
2417 port_actions->portwatch_array, port_actions->portwatch_count);
2418 }
2419
2420 if (port_actions->registered_count) {
2421 if (mach_ports_register(proc_task(p), port_actions->registered_array,
2422 port_actions->registered_count)) {
2423 return EINVAL;
2424 }
2425 /* mach_ports_register() consumed the array */
2426 port_actions->registered_array = NULL;
2427 port_actions->registered_count = 0;
2428 }
2429
2430 return 0;
2431 }
2432
2433 static void
exec_port_actions_destroy(struct exec_port_actions * port_actions)2434 exec_port_actions_destroy(struct exec_port_actions *port_actions)
2435 {
2436 if (port_actions->portwatch_array) {
2437 for (uint32_t i = 0; i < port_actions->portwatch_count; i++) {
2438 ipc_port_t port = NULL;
2439 if ((port = port_actions->portwatch_array[i]) != NULL) {
2440 ipc_port_release_send(port);
2441 }
2442 }
2443 kfree_type(ipc_port_t, port_actions->portwatch_count,
2444 port_actions->portwatch_array);
2445 }
2446
2447 if (port_actions->registered_array) {
2448 for (uint32_t i = 0; i < port_actions->registered_count; i++) {
2449 ipc_port_t port = NULL;
2450 if ((port = port_actions->registered_array[i]) != NULL) {
2451 ipc_port_release_send(port);
2452 }
2453 }
2454 kfree_type(ipc_port_t, port_actions->registered_count,
2455 port_actions->registered_array);
2456 }
2457 }
2458
2459 /*
2460 * exec_handle_port_actions
2461 *
2462 * Description: Go through the _posix_port_actions_t contents,
2463 * calling task_set_special_port, task_set_exception_ports
2464 * and/or audit_session_spawnjoin for the current task.
2465 *
2466 * Parameters: struct image_params * Image parameter block
2467 *
2468 * Returns: 0 Success
2469 * EINVAL Failure
2470 * ENOTSUP Illegal posix_spawn attr flag was set
2471 */
2472 static errno_t
exec_handle_port_actions(struct image_params * imgp,struct exec_port_actions * actions)2473 exec_handle_port_actions(struct image_params *imgp,
2474 struct exec_port_actions *actions)
2475 {
2476 _posix_spawn_port_actions_t pacts = imgp->ip_px_spa;
2477 #if CONFIG_AUDIT
2478 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2479 #endif
2480 _ps_port_action_t *act = NULL;
2481 task_t task = get_threadtask(imgp->ip_new_thread);
2482 ipc_port_t port = NULL;
2483 errno_t ret = 0;
2484 int i, portwatch_i = 0, registered_i = 0;
2485 kern_return_t kr;
2486 boolean_t task_has_watchport_boost = task_has_watchports(current_task());
2487 boolean_t in_exec = (imgp->ip_flags & IMGPF_EXEC);
2488 int ptrauth_task_port_count = 0;
2489
2490 for (i = 0; i < pacts->pspa_count; i++) {
2491 act = &pacts->pspa_actions[i];
2492
2493 switch (act->port_type) {
2494 case PSPA_SPECIAL:
2495 case PSPA_EXCEPTION:
2496 #if CONFIG_AUDIT
2497 case PSPA_AU_SESSION:
2498 #endif
2499 break;
2500 case PSPA_IMP_WATCHPORTS:
2501 if (++actions->portwatch_count > TASK_MAX_WATCHPORT_COUNT) {
2502 ret = EINVAL;
2503 goto done;
2504 }
2505 break;
2506 case PSPA_REGISTERED_PORTS:
2507 if (++actions->registered_count > TASK_PORT_REGISTER_MAX) {
2508 ret = EINVAL;
2509 goto done;
2510 }
2511 break;
2512 case PSPA_PTRAUTH_TASK_PORT:
2513 if (++ptrauth_task_port_count > 1) {
2514 ret = EINVAL;
2515 goto done;
2516 }
2517 break;
2518 default:
2519 ret = EINVAL;
2520 goto done;
2521 }
2522 }
2523
2524 if (actions->portwatch_count) {
2525 if (in_exec && task_has_watchport_boost) {
2526 ret = EINVAL;
2527 goto done;
2528 }
2529 actions->portwatch_array = kalloc_type(ipc_port_t,
2530 actions->portwatch_count, Z_WAITOK | Z_ZERO);
2531 if (actions->portwatch_array == NULL) {
2532 ret = ENOMEM;
2533 goto done;
2534 }
2535 }
2536
2537 if (actions->registered_count) {
2538 actions->registered_array = kalloc_type(ipc_port_t,
2539 actions->registered_count, Z_WAITOK | Z_ZERO);
2540 if (actions->registered_array == NULL) {
2541 ret = ENOMEM;
2542 goto done;
2543 }
2544 }
2545
2546 for (i = 0; i < pacts->pspa_count; i++) {
2547 act = &pacts->pspa_actions[i];
2548
2549 if (MACH_PORT_VALID(act->new_port)) {
2550 kr = ipc_object_copyin(get_task_ipcspace(current_task()),
2551 act->new_port, MACH_MSG_TYPE_COPY_SEND,
2552 (ipc_object_t *) &port, 0, NULL, IPC_OBJECT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND);
2553
2554 if (kr != KERN_SUCCESS) {
2555 ret = EINVAL;
2556 goto done;
2557 }
2558 } else {
2559 /* it's NULL or DEAD */
2560 port = CAST_MACH_NAME_TO_PORT(act->new_port);
2561 }
2562
2563 switch (act->port_type) {
2564 case PSPA_SPECIAL:
2565 kr = task_set_special_port(task, act->which, port);
2566
2567 if (kr != KERN_SUCCESS) {
2568 ret = EINVAL;
2569 }
2570 break;
2571
2572 case PSPA_EXCEPTION:
2573 kr = task_set_exception_ports(task, act->mask, port,
2574 act->behavior, act->flavor);
2575 if (kr != KERN_SUCCESS) {
2576 ret = EINVAL;
2577 }
2578 break;
2579 #if CONFIG_AUDIT
2580 case PSPA_AU_SESSION:
2581 ret = audit_session_spawnjoin(p, task, port);
2582 if (ret) {
2583 /* audit_session_spawnjoin() has already dropped the reference in case of error. */
2584 goto done;
2585 }
2586
2587 break;
2588 #endif
2589 case PSPA_IMP_WATCHPORTS:
2590 if (actions->portwatch_array) {
2591 /* hold on to this till end of spawn */
2592 actions->portwatch_array[portwatch_i++] = port;
2593 } else {
2594 ipc_port_release_send(port);
2595 }
2596 break;
2597 case PSPA_REGISTERED_PORTS:
2598 /* hold on to this till end of spawn */
2599 actions->registered_array[registered_i++] = port;
2600 break;
2601
2602 case PSPA_PTRAUTH_TASK_PORT:
2603 #if defined(HAS_APPLE_PAC)
2604 {
2605 task_t ptr_auth_task = convert_port_to_task(port);
2606
2607 if (ptr_auth_task == TASK_NULL) {
2608 ret = EINVAL;
2609 break;
2610 }
2611
2612 imgp->ip_inherited_shared_region_id =
2613 task_get_vm_shared_region_id_and_jop_pid(ptr_auth_task,
2614 &imgp->ip_inherited_jop_pid);
2615
2616 /* Deallocate task ref returned by convert_port_to_task */
2617 task_deallocate(ptr_auth_task);
2618 }
2619 #endif /* HAS_APPLE_PAC */
2620
2621 /* consume the port right in case of success */
2622 ipc_port_release_send(port);
2623 break;
2624 default:
2625 ret = EINVAL;
2626 break;
2627 }
2628
2629 if (ret) {
2630 /* action failed, so release port resources */
2631 ipc_port_release_send(port);
2632 break;
2633 }
2634 }
2635
2636 done:
2637 if (0 != ret) {
2638 DTRACE_PROC1(spawn__port__failure, mach_port_name_t, act->new_port);
2639 }
2640 return ret;
2641 }
2642
2643 /*
2644 * exec_handle_file_actions
2645 *
2646 * Description: Go through the _posix_file_actions_t contents applying the
2647 * open, close, and dup2 operations to the open file table for
2648 * the current process.
2649 *
2650 * Parameters: struct image_params * Image parameter block
2651 *
2652 * Returns: 0 Success
2653 * ???
2654 *
2655 * Note: Actions are applied in the order specified, with the credential
2656 * of the parent process. This is done to permit the parent
2657 * process to utilize POSIX_SPAWN_RESETIDS to drop privilege in
2658 * the child following operations the child may in fact not be
2659 * normally permitted to perform.
2660 */
2661 static int
exec_handle_file_actions(struct image_params * imgp,short psa_flags)2662 exec_handle_file_actions(struct image_params *imgp, short psa_flags)
2663 {
2664 int error = 0;
2665 int action;
2666 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
2667 _posix_spawn_file_actions_t px_sfap = imgp->ip_px_sfa;
2668 int ival[2]; /* dummy retval for system calls) */
2669 #if CONFIG_AUDIT
2670 struct uthread *uthread = current_uthread();
2671 #endif
2672
2673 for (action = 0; action < px_sfap->psfa_act_count; action++) {
2674 _psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
2675
2676 switch (psfa->psfaa_type) {
2677 case PSFA_OPEN: {
2678 /*
2679 * Open is different, in that it requires the use of
2680 * a path argument, which is normally copied in from
2681 * user space; because of this, we have to support an
2682 * open from kernel space that passes an address space
2683 * context of UIO_SYSSPACE, and casts the address
2684 * argument to a user_addr_t.
2685 */
2686 struct vnode_attr *vap;
2687 struct nameidata *ndp;
2688 int mode = psfa->psfaa_openargs.psfao_mode;
2689 int origfd;
2690 struct {
2691 struct vnode_attr va;
2692 struct nameidata nd;
2693 } *__open_data;
2694
2695 __open_data = kalloc_type(typeof(*__open_data), Z_WAITOK | Z_ZERO);
2696 if (__open_data == NULL) {
2697 error = ENOMEM;
2698 break;
2699 }
2700
2701 vap = &__open_data->va;
2702 ndp = &__open_data->nd;
2703
2704 VATTR_INIT(vap);
2705 /* Mask off all but regular access permissions */
2706 mode = ((mode & ~p->p_fd.fd_cmask) & ALLPERMS) & ~S_ISTXT;
2707 VATTR_SET(vap, va_mode, mode & ACCESSPERMS);
2708
2709 AUDIT_SUBCALL_ENTER(OPEN, p, uthread);
2710
2711 NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
2712 CAST_USER_ADDR_T(psfa->psfaa_openargs.psfao_path),
2713 imgp->ip_vfs_context);
2714
2715 error = open1(imgp->ip_vfs_context, ndp,
2716 psfa->psfaa_openargs.psfao_oflag,
2717 vap, NULL, NULL, &origfd, AUTH_OPEN_NOAUTHFD);
2718
2719 kfree_type(typeof(*__open_data), __open_data);
2720
2721 AUDIT_SUBCALL_EXIT(uthread, error);
2722
2723 /*
2724 * If there's an error, or we get the right fd by
2725 * accident, then drop out here. This is easier than
2726 * reworking all the open code to preallocate fd
2727 * slots, and internally taking one as an argument.
2728 */
2729 if (error || origfd == psfa->psfaa_filedes) {
2730 break;
2731 }
2732
2733 /*
2734 * If we didn't fall out from an error, we ended up
2735 * with the wrong fd; so now we've got to try to dup2
2736 * it to the right one.
2737 */
2738 AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
2739 error = dup2(p, origfd, psfa->psfaa_filedes, ival);
2740 AUDIT_SUBCALL_EXIT(uthread, error);
2741 if (error) {
2742 break;
2743 }
2744
2745 /*
2746 * Finally, close the original fd.
2747 */
2748 AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
2749 error = close_nocancel(p, origfd);
2750 AUDIT_SUBCALL_EXIT(uthread, error);
2751 }
2752 break;
2753
2754 case PSFA_DUP2: {
2755 AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
2756 error = dup2(p, psfa->psfaa_filedes,
2757 psfa->psfaa_dup2args.psfad_newfiledes, ival);
2758 AUDIT_SUBCALL_EXIT(uthread, error);
2759 }
2760 break;
2761
2762 case PSFA_FILEPORT_DUP2: {
2763 ipc_port_t port;
2764 kern_return_t kr;
2765 int origfd;
2766
2767 if (!MACH_PORT_VALID(psfa->psfaa_fileport)) {
2768 error = EINVAL;
2769 break;
2770 }
2771
2772 kr = ipc_object_copyin(get_task_ipcspace(current_task()),
2773 psfa->psfaa_fileport, MACH_MSG_TYPE_COPY_SEND,
2774 (ipc_object_t *) &port, 0, NULL, IPC_OBJECT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND);
2775
2776 if (kr != KERN_SUCCESS) {
2777 error = EINVAL;
2778 break;
2779 }
2780
2781 error = fileport_makefd(p, port, 0, &origfd);
2782
2783 if (IPC_PORT_NULL != port) {
2784 ipc_port_release_send(port);
2785 }
2786
2787 if (error || origfd == psfa->psfaa_dup2args.psfad_newfiledes) {
2788 break;
2789 }
2790
2791 AUDIT_SUBCALL_ENTER(DUP2, p, uthread);
2792 error = dup2(p, origfd,
2793 psfa->psfaa_dup2args.psfad_newfiledes, ival);
2794 AUDIT_SUBCALL_EXIT(uthread, error);
2795 if (error) {
2796 break;
2797 }
2798
2799 AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
2800 error = close_nocancel(p, origfd);
2801 AUDIT_SUBCALL_EXIT(uthread, error);
2802 }
2803 break;
2804
2805 case PSFA_CLOSE: {
2806 AUDIT_SUBCALL_ENTER(CLOSE, p, uthread);
2807 error = close_nocancel(p, psfa->psfaa_filedes);
2808 AUDIT_SUBCALL_EXIT(uthread, error);
2809 }
2810 break;
2811
2812 case PSFA_INHERIT: {
2813 struct fileproc *fp;
2814
2815 /*
2816 * Check to see if the descriptor exists, and
2817 * ensure it's -not- marked as close-on-exec.
2818 *
2819 * Attempting to "inherit" a guarded fd will
2820 * result in a error.
2821 */
2822
2823 proc_fdlock(p);
2824 if ((fp = fp_get_noref_locked(p, psfa->psfaa_filedes)) == NULL) {
2825 error = EBADF;
2826 } else if (fp->fp_guard_attrs) {
2827 error = fp_guard_exception(p, psfa->psfaa_filedes,
2828 fp, kGUARD_EXC_NOCLOEXEC);
2829 } else {
2830 fp->fp_flags &= ~FP_CLOEXEC;
2831 error = 0;
2832 }
2833 proc_fdunlock(p);
2834 }
2835 break;
2836
2837 case PSFA_CHDIR: {
2838 /*
2839 * Chdir is different, in that it requires the use of
2840 * a path argument, which is normally copied in from
2841 * user space; because of this, we have to support a
2842 * chdir from kernel space that passes an address space
2843 * context of UIO_SYSSPACE, and casts the address
2844 * argument to a user_addr_t.
2845 */
2846 struct nameidata *nd;
2847 nd = kalloc_type(struct nameidata,
2848 Z_WAITOK | Z_ZERO | Z_NOFAIL);
2849
2850 AUDIT_SUBCALL_ENTER(CHDIR, p, uthread);
2851 NDINIT(nd, LOOKUP, OP_CHDIR, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
2852 CAST_USER_ADDR_T(psfa->psfaa_chdirargs.psfac_path),
2853 imgp->ip_vfs_context);
2854
2855 error = chdir_internal(p, imgp->ip_vfs_context, nd, 0);
2856 kfree_type(struct nameidata, nd);
2857 AUDIT_SUBCALL_EXIT(uthread, error);
2858 }
2859 break;
2860
2861 case PSFA_FCHDIR: {
2862 struct fchdir_args fchdira;
2863
2864 fchdira.fd = psfa->psfaa_filedes;
2865
2866 AUDIT_SUBCALL_ENTER(FCHDIR, p, uthread);
2867 error = fchdir(p, &fchdira, ival);
2868 AUDIT_SUBCALL_EXIT(uthread, error);
2869 }
2870 break;
2871
2872 default:
2873 error = EINVAL;
2874 break;
2875 }
2876
2877 /* All file actions failures are considered fatal, per POSIX */
2878
2879 if (error) {
2880 if (PSFA_OPEN == psfa->psfaa_type) {
2881 DTRACE_PROC1(spawn__open__failure, uintptr_t,
2882 psfa->psfaa_openargs.psfao_path);
2883 } else {
2884 DTRACE_PROC1(spawn__fd__failure, int, psfa->psfaa_filedes);
2885 }
2886 break;
2887 }
2888 }
2889
2890 if (error != 0 || (psa_flags & POSIX_SPAWN_CLOEXEC_DEFAULT) == 0) {
2891 return error;
2892 }
2893
2894 /*
2895 * If POSIX_SPAWN_CLOEXEC_DEFAULT is set, behave (during
2896 * this spawn only) as if "close on exec" is the default
2897 * disposition of all pre-existing file descriptors. In this case,
2898 * the list of file descriptors mentioned in the file actions
2899 * are the only ones that can be inherited, so mark them now.
2900 *
2901 * The actual closing part comes later, in fdt_exec().
2902 */
2903 proc_fdlock(p);
2904 for (action = 0; action < px_sfap->psfa_act_count; action++) {
2905 _psfa_action_t *psfa = &px_sfap->psfa_act_acts[action];
2906 int fd = psfa->psfaa_filedes;
2907
2908 switch (psfa->psfaa_type) {
2909 case PSFA_DUP2:
2910 case PSFA_FILEPORT_DUP2:
2911 fd = psfa->psfaa_dup2args.psfad_newfiledes;
2912 OS_FALLTHROUGH;
2913 case PSFA_OPEN:
2914 case PSFA_INHERIT:
2915 *fdflags(p, fd) |= UF_INHERIT;
2916 break;
2917
2918 case PSFA_CLOSE:
2919 case PSFA_CHDIR:
2920 case PSFA_FCHDIR:
2921 /*
2922 * Although PSFA_FCHDIR does have a file descriptor, it is not
2923 * *creating* one, thus we do not automatically mark it for
2924 * inheritance under POSIX_SPAWN_CLOEXEC_DEFAULT. A client that
2925 * wishes it to be inherited should use the PSFA_INHERIT action
2926 * explicitly.
2927 */
2928 break;
2929 }
2930 }
2931 proc_fdunlock(p);
2932
2933 return 0;
2934 }
2935
2936 #if CONFIG_MACF
2937 /*
2938 * Check that the extension's data is within the bounds of the
2939 * allocation storing all extensions' data
2940 */
2941 static inline errno_t
exec_spawnattr_validate_policyext_data(const struct ip_px_smpx_s * px_s,const _ps_mac_policy_extension_t * ext)2942 exec_spawnattr_validate_policyext_data(const struct ip_px_smpx_s *px_s,
2943 const _ps_mac_policy_extension_t *ext)
2944 {
2945 uint64_t dataend;
2946
2947 if (__improbable(os_add_overflow(ext->dataoff, ext->datalen, &dataend))) {
2948 return EOVERFLOW;
2949 }
2950 if (__improbable(dataend > px_s->datalen)) {
2951 return EINVAL;
2952 }
2953
2954 return 0;
2955 }
2956
2957 /*
2958 * exec_spawnattr_getmacpolicyinfo
2959 */
2960 void *
exec_spawnattr_getmacpolicyinfo(const void * macextensions,const char * policyname,size_t * lenp)2961 exec_spawnattr_getmacpolicyinfo(const void *macextensions, const char *policyname, size_t *lenp)
2962 {
2963 const struct ip_px_smpx_s *px_s = macextensions;
2964 const struct _posix_spawn_mac_policy_extensions *psmx = NULL;
2965 int i;
2966
2967 if (px_s == NULL) {
2968 return NULL;
2969 }
2970
2971 psmx = px_s->array;
2972 if (psmx == NULL) {
2973 return NULL;
2974 }
2975
2976 for (i = 0; i < psmx->psmx_count; i++) {
2977 const _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
2978 if (strncmp(extension->policyname, policyname, sizeof(extension->policyname)) == 0) {
2979 if (__improbable(exec_spawnattr_validate_policyext_data(px_s, extension))) {
2980 panic("invalid mac policy extension data");
2981 }
2982 if (lenp != NULL) {
2983 *lenp = (size_t)extension->datalen;
2984 }
2985 return (void *)((uintptr_t)px_s->data + extension->dataoff);
2986 }
2987 }
2988
2989 if (lenp != NULL) {
2990 *lenp = 0;
2991 }
2992 return NULL;
2993 }
2994
2995 static int
spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc * px_args,struct ip_px_smpx_s * pxsp)2996 spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc *px_args,
2997 struct ip_px_smpx_s *pxsp)
2998 {
2999 _posix_spawn_mac_policy_extensions_t psmx = NULL;
3000 uint8_t *data = NULL;
3001 uint64_t datalen = 0;
3002 uint64_t dataoff = 0;
3003 int error = 0;
3004
3005 bzero(pxsp, sizeof(*pxsp));
3006
3007 if (px_args->mac_extensions_size < PS_MAC_EXTENSIONS_SIZE(1) ||
3008 px_args->mac_extensions_size > PAGE_SIZE) {
3009 error = EINVAL;
3010 goto bad;
3011 }
3012
3013 psmx = kalloc_data(px_args->mac_extensions_size, Z_WAITOK);
3014 if (psmx == NULL) {
3015 error = ENOMEM;
3016 goto bad;
3017 }
3018
3019 error = copyin(px_args->mac_extensions, psmx, px_args->mac_extensions_size);
3020 if (error) {
3021 goto bad;
3022 }
3023
3024 size_t extsize = PS_MAC_EXTENSIONS_SIZE(psmx->psmx_count);
3025 if (extsize == 0 || extsize > px_args->mac_extensions_size) {
3026 error = EINVAL;
3027 goto bad;
3028 }
3029
3030 for (int i = 0; i < psmx->psmx_count; i++) {
3031 _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
3032 if (extension->datalen == 0 || extension->datalen > PAGE_SIZE) {
3033 error = EINVAL;
3034 goto bad;
3035 }
3036 if (__improbable(os_add_overflow(datalen, extension->datalen, &datalen))) {
3037 error = ENOMEM;
3038 goto bad;
3039 }
3040 }
3041
3042 data = kalloc_data((vm_size_t)datalen, Z_WAITOK);
3043 if (data == NULL) {
3044 error = ENOMEM;
3045 goto bad;
3046 }
3047
3048 for (int i = 0; i < psmx->psmx_count; i++) {
3049 _ps_mac_policy_extension_t *extension = &psmx->psmx_extensions[i];
3050
3051 #if !__LP64__
3052 if (extension->data > UINT32_MAX) {
3053 goto bad;
3054 }
3055 #endif
3056 error = copyin((user_addr_t)extension->data, &data[dataoff], (size_t)extension->datalen);
3057 if (error) {
3058 error = ENOMEM;
3059 goto bad;
3060 }
3061 extension->dataoff = dataoff;
3062 dataoff += extension->datalen;
3063 }
3064
3065 pxsp->array = psmx;
3066 pxsp->data = data;
3067 pxsp->datalen = datalen;
3068 return 0;
3069
3070 bad:
3071 kfree_data(psmx, px_args->mac_extensions_size);
3072 kfree_data(data, (vm_size_t)datalen);
3073 return error;
3074 }
3075 #endif /* CONFIG_MACF */
3076
3077 #if CONFIG_COALITIONS
3078 static inline void
spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES])3079 spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES])
3080 {
3081 for (int c = 0; c < COALITION_NUM_TYPES; c++) {
3082 if (coal[c]) {
3083 coalition_remove_active(coal[c]);
3084 coalition_release(coal[c]);
3085 }
3086 }
3087 }
3088 #endif
3089
3090 #if CONFIG_PERSONAS
3091 static int
spawn_validate_persona(struct _posix_spawn_persona_info * px_persona)3092 spawn_validate_persona(struct _posix_spawn_persona_info *px_persona)
3093 {
3094 int error = 0;
3095 struct persona *persona = NULL;
3096
3097 if (!IOCurrentTaskHasEntitlement( PERSONA_MGMT_ENTITLEMENT)) {
3098 return EPERM;
3099 }
3100
3101 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
3102 if (px_persona->pspi_ngroups > NGROUPS_MAX) {
3103 return EINVAL;
3104 }
3105 }
3106
3107 persona = persona_lookup(px_persona->pspi_id);
3108 if (!persona) {
3109 error = ESRCH;
3110 goto out;
3111 }
3112
3113 out:
3114 if (persona) {
3115 persona_put(persona);
3116 }
3117
3118 return error;
3119 }
3120
3121 static int
spawn_persona_adopt(proc_t p,struct _posix_spawn_persona_info * px_persona)3122 spawn_persona_adopt(proc_t p, struct _posix_spawn_persona_info *px_persona)
3123 {
3124 int ret;
3125 kauth_cred_t cred;
3126 struct persona *persona = NULL;
3127
3128 /*
3129 * we want to spawn into the given persona, but we want to override
3130 * the kauth with a different UID/GID combo
3131 */
3132 persona = persona_lookup(px_persona->pspi_id);
3133 if (!persona) {
3134 return ESRCH;
3135 }
3136
3137 cred = kauth_cred_proc_ref(p);
3138
3139 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_UID) {
3140 cred = kauth_cred_setresuid(cred,
3141 px_persona->pspi_uid,
3142 px_persona->pspi_uid,
3143 px_persona->pspi_uid,
3144 KAUTH_UID_NONE);
3145 }
3146
3147 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GID) {
3148 cred = kauth_cred_setresgid(cred,
3149 px_persona->pspi_gid,
3150 px_persona->pspi_gid,
3151 px_persona->pspi_gid);
3152 }
3153
3154 if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) {
3155 cred = kauth_cred_setgroups(cred,
3156 px_persona->pspi_groups,
3157 px_persona->pspi_ngroups,
3158 px_persona->pspi_gmuid);
3159 }
3160
3161 ret = persona_proc_adopt(p, persona, cred);
3162
3163 kauth_cred_unref(&cred);
3164 persona_put(persona);
3165 return ret;
3166 }
3167 #endif
3168
3169 #if __arm64__
3170 #if DEVELOPMENT || DEBUG
3171 TUNABLE(int, legacy_footprint_entitlement_mode, "legacy_footprint_entitlement_mode",
3172 LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE);
3173
3174 __startup_func
3175 static void
legacy_footprint_entitlement_mode_init(void)3176 legacy_footprint_entitlement_mode_init(void)
3177 {
3178 /*
3179 * legacy_footprint_entitlement_mode specifies the behavior we want associated
3180 * with the entitlement. The supported modes are:
3181 *
3182 * LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE:
3183 * Indicates that we want every process to have the memory accounting
3184 * that is available in iOS 12.0 and beyond.
3185 *
3186 * LEGACY_FOOTPRINT_ENTITLEMENT_IOS11_ACCT:
3187 * Indicates that for every process that has the 'legacy footprint entitlement',
3188 * we want to give it the old iOS 11.0 accounting behavior which accounted some
3189 * of the process's memory to the kernel.
3190 *
3191 * LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE:
3192 * Indicates that for every process that has the 'legacy footprint entitlement',
3193 * we want it to have a higher memory limit which will help them acclimate to the
3194 * iOS 12.0 (& beyond) accounting behavior that does the right accounting.
3195 * The bonus added to the system-wide task limit to calculate this higher memory limit
3196 * is available in legacy_footprint_bonus_mb.
3197 */
3198
3199 if (legacy_footprint_entitlement_mode < LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE ||
3200 legacy_footprint_entitlement_mode > LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE) {
3201 legacy_footprint_entitlement_mode = LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE;
3202 }
3203 }
3204 STARTUP(TUNABLES, STARTUP_RANK_MIDDLE, legacy_footprint_entitlement_mode_init);
3205 #else
3206 const int legacy_footprint_entitlement_mode = LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE;
3207 #endif
3208
3209 static inline void
proc_legacy_footprint_entitled(proc_t p,task_t task)3210 proc_legacy_footprint_entitled(proc_t p, task_t task)
3211 {
3212 #pragma unused(p)
3213 boolean_t legacy_footprint_entitled;
3214
3215 switch (legacy_footprint_entitlement_mode) {
3216 case LEGACY_FOOTPRINT_ENTITLEMENT_IGNORE:
3217 /* the entitlement is ignored */
3218 break;
3219 case LEGACY_FOOTPRINT_ENTITLEMENT_IOS11_ACCT:
3220 /* the entitlement grants iOS11 legacy accounting */
3221 legacy_footprint_entitled = memorystatus_task_has_legacy_footprint_entitlement(proc_task(p));
3222 if (legacy_footprint_entitled) {
3223 task_set_legacy_footprint(task);
3224 }
3225 break;
3226 case LEGACY_FOOTPRINT_ENTITLEMENT_LIMIT_INCREASE:
3227 /* the entitlement grants a footprint limit increase */
3228 legacy_footprint_entitled = memorystatus_task_has_legacy_footprint_entitlement(proc_task(p));
3229 if (legacy_footprint_entitled) {
3230 task_set_extra_footprint_limit(task);
3231 }
3232 break;
3233 default:
3234 break;
3235 }
3236 }
3237
3238 static inline void
proc_ios13extended_footprint_entitled(proc_t p,task_t task)3239 proc_ios13extended_footprint_entitled(proc_t p, task_t task)
3240 {
3241 #pragma unused(p)
3242 boolean_t ios13extended_footprint_entitled;
3243
3244 /* the entitlement grants a footprint limit increase */
3245 ios13extended_footprint_entitled = memorystatus_task_has_ios13extended_footprint_limit(proc_task(p));
3246 if (ios13extended_footprint_entitled) {
3247 task_set_ios13extended_footprint_limit(task);
3248 }
3249 }
3250
3251 static inline void
proc_increased_memory_limit_entitled(proc_t p,task_t task)3252 proc_increased_memory_limit_entitled(proc_t p, task_t task)
3253 {
3254 bool entitled = memorystatus_task_has_increased_memory_limit_entitlement(task);
3255
3256 if (entitled) {
3257 memorystatus_act_on_entitled_task_limit(p);
3258 }
3259 }
3260
3261 /*
3262 * Check for any of the various entitlements that permit a higher
3263 * task footprint limit or alternate accounting and apply them.
3264 */
3265 static inline void
proc_footprint_entitlement_hacks(proc_t p,task_t task)3266 proc_footprint_entitlement_hacks(proc_t p, task_t task)
3267 {
3268 proc_legacy_footprint_entitled(p, task);
3269 proc_ios13extended_footprint_entitled(p, task);
3270 proc_increased_memory_limit_entitled(p, task);
3271 }
3272 #endif /* __arm64__ */
3273
3274 /*
3275 * Processes with certain entitlements are granted a jumbo-size VM map.
3276 */
3277 static inline void
proc_apply_jit_and_vm_policies(struct image_params * imgp,proc_t p,task_t task)3278 proc_apply_jit_and_vm_policies(struct image_params *imgp, proc_t p, task_t task)
3279 {
3280 #if CONFIG_MACF
3281 bool jit_entitled = false;
3282 #endif /* CONFIG_MACF */
3283 bool needs_jumbo_va = false;
3284 struct _posix_spawnattr *psa = imgp->ip_px_sa;
3285
3286 #if CONFIG_MACF
3287 jit_entitled = (mac_proc_check_map_anon(p, 0, 0, 0, MAP_JIT, NULL) == 0);
3288 needs_jumbo_va = jit_entitled || IOTaskHasEntitlement(task,
3289 "com.apple.developer.kernel.extended-virtual-addressing") ||
3290 memorystatus_task_has_increased_memory_limit_entitlement(task);
3291 #else
3292 #pragma unused(p)
3293 #endif /* CONFIG_MACF */
3294
3295 if (needs_jumbo_va) {
3296 vm_map_set_jumbo(get_task_map(task));
3297 }
3298
3299 if (psa && psa->psa_max_addr) {
3300 vm_map_set_max_addr(get_task_map(task), psa->psa_max_addr);
3301 }
3302
3303 #if CONFIG_MAP_RANGES
3304 if (task_get_platform_binary(task)) {
3305 /*
3306 * This must be done last as it needs to observe
3307 * any kind of VA space growth that was requested
3308 */
3309 vm_map_range_configure(get_task_map(task));
3310 }
3311 #endif /* CONFIG_MAP_RANGES */
3312
3313 #if CONFIG_MACF
3314 if (jit_entitled) {
3315 vm_map_set_jit_entitled(get_task_map(task));
3316
3317 }
3318 #endif /* CONFIG_MACF */
3319
3320 #if defined(__arm64e__)
3321 if (imgp->ip_flags & IMGPF_HW_TPRO) {
3322 vm_map_set_tpro(get_task_map(task));
3323 }
3324 #endif /* __arm64e__ */
3325 }
3326
3327 static int
spawn_posix_cred_adopt(proc_t p,struct _posix_spawn_posix_cred_info * px_pcred_info)3328 spawn_posix_cred_adopt(proc_t p,
3329 struct _posix_spawn_posix_cred_info *px_pcred_info)
3330 {
3331 int error = 0;
3332
3333 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GID) {
3334 struct setgid_args args = {
3335 .gid = px_pcred_info->pspci_gid,
3336 };
3337 error = setgid(p, &args, NULL);
3338 if (error) {
3339 return error;
3340 }
3341 }
3342
3343 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
3344 error = setgroups_internal(p,
3345 px_pcred_info->pspci_ngroups,
3346 px_pcred_info->pspci_groups,
3347 px_pcred_info->pspci_gmuid);
3348 if (error) {
3349 return error;
3350 }
3351 }
3352
3353 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_UID) {
3354 struct setuid_args args = {
3355 .uid = px_pcred_info->pspci_uid,
3356 };
3357 error = setuid(p, &args, NULL);
3358 if (error) {
3359 return error;
3360 }
3361 }
3362 return 0;
3363 }
3364
3365 /*
3366 * posix_spawn
3367 *
3368 * Parameters: uap->pid Pointer to pid return area
3369 * uap->fname File name to exec
3370 * uap->argp Argument list
3371 * uap->envp Environment list
3372 *
3373 * Returns: 0 Success
3374 * EINVAL Invalid argument
3375 * ENOTSUP Not supported
3376 * ENOEXEC Executable file format error
3377 * exec_activate_image:EINVAL Invalid argument
3378 * exec_activate_image:EACCES Permission denied
3379 * exec_activate_image:EINTR Interrupted function
3380 * exec_activate_image:ENOMEM Not enough space
3381 * exec_activate_image:EFAULT Bad address
3382 * exec_activate_image:ENAMETOOLONG Filename too long
3383 * exec_activate_image:ENOEXEC Executable file format error
3384 * exec_activate_image:ETXTBSY Text file busy [misuse of error code]
3385 * exec_activate_image:EAUTH Image decryption failed
3386 * exec_activate_image:EBADEXEC The executable is corrupt/unknown
3387 * exec_activate_image:???
3388 * mac_execve_enter:???
3389 *
3390 * TODO: Expect to need __mac_posix_spawn() at some point...
3391 * Handle posix_spawnattr_t
3392 * Handle posix_spawn_file_actions_t
3393 */
3394 int
posix_spawn(proc_t ap,struct posix_spawn_args * uap,int32_t * retval)3395 posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval)
3396 {
3397 proc_t p = ap;
3398 user_addr_t pid = uap->pid;
3399 int ival[2]; /* dummy retval for setpgid() */
3400 char *subsystem_root_path = NULL;
3401 struct image_params *imgp = NULL;
3402 struct vnode_attr *vap = NULL;
3403 struct vnode_attr *origvap = NULL;
3404 struct uthread *uthread = 0; /* compiler complains if not set to 0*/
3405 int error, sig;
3406 int is_64 = IS_64BIT_PROCESS(p);
3407 struct vfs_context context;
3408 struct user__posix_spawn_args_desc px_args = {};
3409 struct _posix_spawnattr px_sa = {};
3410 _posix_spawn_file_actions_t px_sfap = NULL;
3411 _posix_spawn_port_actions_t px_spap = NULL;
3412 struct __kern_sigaction vec;
3413 boolean_t spawn_no_exec = FALSE;
3414 boolean_t proc_transit_set = TRUE;
3415 boolean_t proc_signal_set = TRUE;
3416 boolean_t exec_done = FALSE;
3417 os_reason_t exec_failure_reason = NULL;
3418
3419 struct exec_port_actions port_actions = { };
3420 vm_size_t px_sa_offset = offsetof(struct _posix_spawnattr, psa_ports);
3421 task_t old_task = current_task();
3422 task_t new_task = NULL;
3423 boolean_t should_release_proc_ref = FALSE;
3424 void *inherit = NULL;
3425 uint8_t crash_behavior = 0;
3426 uint64_t crash_behavior_deadline = 0;
3427 #if CONFIG_PERSONAS
3428 struct _posix_spawn_persona_info *px_persona = NULL;
3429 #endif
3430 struct _posix_spawn_posix_cred_info *px_pcred_info = NULL;
3431 struct {
3432 struct image_params imgp;
3433 struct vnode_attr va;
3434 struct vnode_attr origva;
3435 } *__spawn_data;
3436
3437 /*
3438 * Allocate a big chunk for locals instead of using stack since these
3439 * structures are pretty big.
3440 */
3441 __spawn_data = kalloc_type(typeof(*__spawn_data), Z_WAITOK | Z_ZERO);
3442 if (__spawn_data == NULL) {
3443 error = ENOMEM;
3444 goto bad;
3445 }
3446 imgp = &__spawn_data->imgp;
3447 vap = &__spawn_data->va;
3448 origvap = &__spawn_data->origva;
3449
3450 /* Initialize the common data in the image_params structure */
3451 imgp->ip_user_fname = uap->path;
3452 imgp->ip_user_argv = uap->argv;
3453 imgp->ip_user_envv = uap->envp;
3454 imgp->ip_vattr = vap;
3455 imgp->ip_origvattr = origvap;
3456 imgp->ip_vfs_context = &context;
3457 imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE);
3458 imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
3459 imgp->ip_mac_return = 0;
3460 imgp->ip_px_persona = NULL;
3461 imgp->ip_px_pcred_info = NULL;
3462 imgp->ip_cs_error = OS_REASON_NULL;
3463 imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
3464 imgp->ip_subsystem_root_path = NULL;
3465 imgp->ip_inherited_shared_region_id = NULL;
3466 imgp->ip_inherited_jop_pid = 0;
3467 uthread_set_exec_data(current_uthread(), imgp);
3468
3469 if (uap->adesc != USER_ADDR_NULL) {
3470 if (is_64) {
3471 error = copyin(uap->adesc, &px_args, sizeof(px_args));
3472 } else {
3473 struct user32__posix_spawn_args_desc px_args32;
3474
3475 error = copyin(uap->adesc, &px_args32, sizeof(px_args32));
3476
3477 /*
3478 * Convert arguments descriptor from external 32 bit
3479 * representation to internal 64 bit representation
3480 */
3481 px_args.attr_size = px_args32.attr_size;
3482 px_args.attrp = CAST_USER_ADDR_T(px_args32.attrp);
3483 px_args.file_actions_size = px_args32.file_actions_size;
3484 px_args.file_actions = CAST_USER_ADDR_T(px_args32.file_actions);
3485 px_args.port_actions_size = px_args32.port_actions_size;
3486 px_args.port_actions = CAST_USER_ADDR_T(px_args32.port_actions);
3487 px_args.mac_extensions_size = px_args32.mac_extensions_size;
3488 px_args.mac_extensions = CAST_USER_ADDR_T(px_args32.mac_extensions);
3489 px_args.coal_info_size = px_args32.coal_info_size;
3490 px_args.coal_info = CAST_USER_ADDR_T(px_args32.coal_info);
3491 px_args.persona_info_size = px_args32.persona_info_size;
3492 px_args.persona_info = CAST_USER_ADDR_T(px_args32.persona_info);
3493 px_args.posix_cred_info_size = px_args32.posix_cred_info_size;
3494 px_args.posix_cred_info = CAST_USER_ADDR_T(px_args32.posix_cred_info);
3495 px_args.subsystem_root_path_size = px_args32.subsystem_root_path_size;
3496 px_args.subsystem_root_path = CAST_USER_ADDR_T(px_args32.subsystem_root_path);
3497 }
3498 if (error) {
3499 goto bad;
3500 }
3501
3502 if (px_args.attr_size != 0) {
3503 /*
3504 * We are not copying the port_actions pointer,
3505 * because we already have it from px_args.
3506 * This is a bit fragile: <rdar://problem/16427422>
3507 */
3508
3509 if ((error = copyin(px_args.attrp, &px_sa, px_sa_offset)) != 0) {
3510 goto bad;
3511 }
3512
3513 imgp->ip_px_sa = &px_sa;
3514 }
3515 if (px_args.file_actions_size != 0) {
3516 /* Limit file_actions to allowed number of open files */
3517 size_t maxfa_size = PSF_ACTIONS_SIZE(proc_limitgetcur_nofile(p));
3518
3519 if (px_args.file_actions_size < PSF_ACTIONS_SIZE(1) ||
3520 maxfa_size == 0 || px_args.file_actions_size > maxfa_size) {
3521 error = EINVAL;
3522 goto bad;
3523 }
3524
3525 px_sfap = kalloc_data(px_args.file_actions_size, Z_WAITOK);
3526 if (px_sfap == NULL) {
3527 error = ENOMEM;
3528 goto bad;
3529 }
3530 imgp->ip_px_sfa = px_sfap;
3531
3532 if ((error = copyin(px_args.file_actions, px_sfap,
3533 px_args.file_actions_size)) != 0) {
3534 goto bad;
3535 }
3536
3537 /* Verify that the action count matches the struct size */
3538 size_t psfsize = PSF_ACTIONS_SIZE(px_sfap->psfa_act_count);
3539 if (psfsize == 0 || psfsize != px_args.file_actions_size) {
3540 error = EINVAL;
3541 goto bad;
3542 }
3543 }
3544 if (px_args.port_actions_size != 0) {
3545 /* Limit port_actions to one page of data */
3546 if (px_args.port_actions_size < PS_PORT_ACTIONS_SIZE(1) ||
3547 px_args.port_actions_size > PAGE_SIZE) {
3548 error = EINVAL;
3549 goto bad;
3550 }
3551
3552 px_spap = kalloc_data(px_args.port_actions_size, Z_WAITOK);
3553 if (px_spap == NULL) {
3554 error = ENOMEM;
3555 goto bad;
3556 }
3557 imgp->ip_px_spa = px_spap;
3558
3559 if ((error = copyin(px_args.port_actions, px_spap,
3560 px_args.port_actions_size)) != 0) {
3561 goto bad;
3562 }
3563
3564 /* Verify that the action count matches the struct size */
3565 size_t pasize = PS_PORT_ACTIONS_SIZE(px_spap->pspa_count);
3566 if (pasize == 0 || pasize != px_args.port_actions_size) {
3567 error = EINVAL;
3568 goto bad;
3569 }
3570 }
3571 #if CONFIG_PERSONAS
3572 /* copy in the persona info */
3573 if (px_args.persona_info_size != 0 && px_args.persona_info != 0) {
3574 /* for now, we need the exact same struct in user space */
3575 if (px_args.persona_info_size != sizeof(*px_persona)) {
3576 error = ERANGE;
3577 goto bad;
3578 }
3579
3580 px_persona = kalloc_data(px_args.persona_info_size, Z_WAITOK);
3581 if (px_persona == NULL) {
3582 error = ENOMEM;
3583 goto bad;
3584 }
3585 imgp->ip_px_persona = px_persona;
3586
3587 if ((error = copyin(px_args.persona_info, px_persona,
3588 px_args.persona_info_size)) != 0) {
3589 goto bad;
3590 }
3591 if ((error = spawn_validate_persona(px_persona)) != 0) {
3592 goto bad;
3593 }
3594 }
3595 #endif
3596 /* copy in the posix cred info */
3597 if (px_args.posix_cred_info_size != 0 && px_args.posix_cred_info != 0) {
3598 /* for now, we need the exact same struct in user space */
3599 if (px_args.posix_cred_info_size != sizeof(*px_pcred_info)) {
3600 error = ERANGE;
3601 goto bad;
3602 }
3603
3604 if (!kauth_cred_issuser(kauth_cred_get())) {
3605 error = EPERM;
3606 goto bad;
3607 }
3608
3609 px_pcred_info = kalloc_data(px_args.posix_cred_info_size, Z_WAITOK);
3610 if (px_pcred_info == NULL) {
3611 error = ENOMEM;
3612 goto bad;
3613 }
3614 imgp->ip_px_pcred_info = px_pcred_info;
3615
3616 if ((error = copyin(px_args.posix_cred_info, px_pcred_info,
3617 px_args.posix_cred_info_size)) != 0) {
3618 goto bad;
3619 }
3620
3621 if (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_GROUPS) {
3622 if (px_pcred_info->pspci_ngroups > NGROUPS_MAX) {
3623 error = EINVAL;
3624 goto bad;
3625 }
3626 }
3627 }
3628 #if CONFIG_MACF
3629 if (px_args.mac_extensions_size != 0) {
3630 if ((error = spawn_copyin_macpolicyinfo(&px_args, (struct ip_px_smpx_s *)&imgp->ip_px_smpx)) != 0) {
3631 goto bad;
3632 }
3633 }
3634 #endif /* CONFIG_MACF */
3635 if ((px_args.subsystem_root_path_size > 0) && (px_args.subsystem_root_path_size <= MAXPATHLEN)) {
3636 /*
3637 * If a valid-looking subsystem root has been
3638 * specified...
3639 */
3640 if (IOTaskHasEntitlement(old_task, SPAWN_SUBSYSTEM_ROOT_ENTITLEMENT)) {
3641 /*
3642 * ...AND the parent has the entitlement, copy
3643 * the subsystem root path in.
3644 */
3645 subsystem_root_path = zalloc_flags(ZV_NAMEI,
3646 Z_WAITOK | Z_ZERO | Z_NOFAIL);
3647
3648 if ((error = copyin(px_args.subsystem_root_path, subsystem_root_path, px_args.subsystem_root_path_size))) {
3649 goto bad;
3650 }
3651
3652 /* Paranoia */
3653 subsystem_root_path[px_args.subsystem_root_path_size - 1] = 0;
3654 }
3655 }
3656 }
3657
3658 if (IOTaskHasEntitlement(old_task, SPAWN_SET_PANIC_CRASH_BEHAVIOR)) {
3659 /* Truncate to uint8_t since we only support 2 flags for now */
3660 crash_behavior = (uint8_t)px_sa.psa_crash_behavior;
3661 crash_behavior_deadline = px_sa.psa_crash_behavior_deadline;
3662 }
3663
3664 /* set uthread to parent */
3665 uthread = current_uthread();
3666
3667 /*
3668 * <rdar://6640530>; this does not result in a behaviour change
3669 * relative to Leopard, so there should not be any existing code
3670 * which depends on it.
3671 */
3672
3673 if (imgp->ip_px_sa != NULL) {
3674 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
3675 if ((psa->psa_options & PSA_OPTION_PLUGIN_HOST_DISABLE_A_KEYS) == PSA_OPTION_PLUGIN_HOST_DISABLE_A_KEYS) {
3676 imgp->ip_flags |= IMGPF_PLUGIN_HOST_DISABLE_A_KEYS;
3677 }
3678 #if (DEVELOPMENT || DEBUG)
3679 if ((psa->psa_options & PSA_OPTION_ALT_ROSETTA) == PSA_OPTION_ALT_ROSETTA) {
3680 imgp->ip_flags |= (IMGPF_ROSETTA | IMGPF_ALT_ROSETTA);
3681 }
3682 #endif
3683
3684 if ((error = exec_validate_spawnattr_policy(psa->psa_apptype)) != 0) {
3685 goto bad;
3686 }
3687 }
3688
3689 /*
3690 * If we don't have the extension flag that turns "posix_spawn()"
3691 * into "execve() with options", then we will be creating a new
3692 * process which does not inherit memory from the parent process,
3693 * which is one of the most expensive things about using fork()
3694 * and execve().
3695 */
3696 if (imgp->ip_px_sa == NULL || !(px_sa.psa_flags & POSIX_SPAWN_SETEXEC)) {
3697 /* Set the new task's coalition, if it is requested. */
3698 coalition_t coal[COALITION_NUM_TYPES] = { COALITION_NULL };
3699 #if CONFIG_COALITIONS
3700 int i, ncoals;
3701 kern_return_t kr = KERN_SUCCESS;
3702 struct _posix_spawn_coalition_info coal_info;
3703 int coal_role[COALITION_NUM_TYPES];
3704
3705 if (imgp->ip_px_sa == NULL || !px_args.coal_info) {
3706 goto do_fork1;
3707 }
3708
3709 memset(&coal_info, 0, sizeof(coal_info));
3710
3711 if (px_args.coal_info_size > sizeof(coal_info)) {
3712 px_args.coal_info_size = sizeof(coal_info);
3713 }
3714 error = copyin(px_args.coal_info,
3715 &coal_info, px_args.coal_info_size);
3716 if (error != 0) {
3717 goto bad;
3718 }
3719
3720 ncoals = 0;
3721 for (i = 0; i < COALITION_NUM_TYPES; i++) {
3722 uint64_t cid = coal_info.psci_info[i].psci_id;
3723 if (cid != 0) {
3724 /*
3725 * don't allow tasks which are not in a
3726 * privileged coalition to spawn processes
3727 * into coalitions other than their own
3728 */
3729 if (!task_is_in_privileged_coalition(proc_task(p), i) &&
3730 !IOTaskHasEntitlement(proc_task(p), COALITION_SPAWN_ENTITLEMENT)) {
3731 coal_dbg("ERROR: %d not in privilegd "
3732 "coalition of type %d",
3733 proc_getpid(p), i);
3734 spawn_coalitions_release_all(coal);
3735 error = EPERM;
3736 goto bad;
3737 }
3738
3739 coal_dbg("searching for coalition id:%llu", cid);
3740 /*
3741 * take a reference and activation on the
3742 * coalition to guard against free-while-spawn
3743 * races
3744 */
3745 coal[i] = coalition_find_and_activate_by_id(cid);
3746 if (coal[i] == COALITION_NULL) {
3747 coal_dbg("could not find coalition id:%llu "
3748 "(perhaps it has been terminated or reaped)", cid);
3749 /*
3750 * release any other coalition's we
3751 * may have a reference to
3752 */
3753 spawn_coalitions_release_all(coal);
3754 error = ESRCH;
3755 goto bad;
3756 }
3757 if (coalition_type(coal[i]) != i) {
3758 coal_dbg("coalition with id:%lld is not of type:%d"
3759 " (it's type:%d)", cid, i, coalition_type(coal[i]));
3760 spawn_coalitions_release_all(coal);
3761 error = ESRCH;
3762 goto bad;
3763 }
3764 coal_role[i] = coal_info.psci_info[i].psci_role;
3765 ncoals++;
3766 }
3767 }
3768 if (ncoals < COALITION_NUM_TYPES) {
3769 /*
3770 * If the user is attempting to spawn into a subset of
3771 * the known coalition types, then make sure they have
3772 * _at_least_ specified a resource coalition. If not,
3773 * the following fork1() call will implicitly force an
3774 * inheritance from 'p' and won't actually spawn the
3775 * new task into the coalitions the user specified.
3776 * (also the call to coalitions_set_roles will panic)
3777 */
3778 if (coal[COALITION_TYPE_RESOURCE] == COALITION_NULL) {
3779 spawn_coalitions_release_all(coal);
3780 error = EINVAL;
3781 goto bad;
3782 }
3783 }
3784 do_fork1:
3785 #endif /* CONFIG_COALITIONS */
3786
3787 /*
3788 * note that this will implicitly inherit the
3789 * caller's persona (if it exists)
3790 */
3791 error = fork1(p, &imgp->ip_new_thread, PROC_CREATE_SPAWN, coal);
3792 /* returns a thread and task reference */
3793
3794 if (error == 0) {
3795 new_task = get_threadtask(imgp->ip_new_thread);
3796 }
3797 #if CONFIG_COALITIONS
3798 /* set the roles of this task within each given coalition */
3799 if (error == 0) {
3800 kr = coalitions_set_roles(coal, new_task, coal_role);
3801 if (kr != KERN_SUCCESS) {
3802 error = EINVAL;
3803 }
3804 if (kdebug_debugid_enabled(MACHDBG_CODE(DBG_MACH_COALITION,
3805 MACH_COALITION_ADOPT))) {
3806 for (i = 0; i < COALITION_NUM_TYPES; i++) {
3807 if (coal[i] != COALITION_NULL) {
3808 /*
3809 * On 32-bit targets, uniqueid
3810 * will get truncated to 32 bits
3811 */
3812 KDBG_RELEASE(MACHDBG_CODE(
3813 DBG_MACH_COALITION,
3814 MACH_COALITION_ADOPT),
3815 coalition_id(coal[i]),
3816 get_task_uniqueid(new_task));
3817 }
3818 }
3819 }
3820 }
3821
3822 /* drop our references and activations - fork1() now holds them */
3823 spawn_coalitions_release_all(coal);
3824 #endif /* CONFIG_COALITIONS */
3825 if (error != 0) {
3826 goto bad;
3827 }
3828 imgp->ip_flags |= IMGPF_SPAWN; /* spawn w/o exec */
3829 spawn_no_exec = TRUE; /* used in later tests */
3830 } else {
3831 /* Adjust the user proc count */
3832 (void)chgproccnt(kauth_getruid(), 1);
3833 /*
3834 * For execve case, create a new proc, task and thread
3835 * but don't make the proc visible to userland. After
3836 * image activation, the new proc would take place of
3837 * the old proc in pid hash and other lists that make
3838 * the proc visible to the system.
3839 */
3840 imgp->ip_new_thread = cloneproc(old_task, NULL, p, CLONEPROC_FLAGS_FOR_EXEC);
3841
3842 /* task and thread ref returned by cloneproc */
3843 if (imgp->ip_new_thread == NULL) {
3844 (void)chgproccnt(kauth_getruid(), -1);
3845 error = ENOMEM;
3846 goto bad;
3847 }
3848
3849 new_task = get_threadtask(imgp->ip_new_thread);
3850 imgp->ip_flags |= IMGPF_EXEC;
3851 }
3852
3853 p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
3854
3855 if (spawn_no_exec) {
3856 /*
3857 * We had to wait until this point before firing the
3858 * proc:::create probe, otherwise p would not point to the
3859 * child process.
3860 */
3861 DTRACE_PROC1(create, proc_t, p);
3862 }
3863 assert(p != NULL);
3864
3865 if (subsystem_root_path) {
3866 /* If a subsystem root was specified, swap it in */
3867 char * old_subsystem_root_path = p->p_subsystem_root_path;
3868 p->p_subsystem_root_path = subsystem_root_path;
3869 subsystem_root_path = old_subsystem_root_path;
3870 }
3871
3872 p->p_crash_behavior = crash_behavior;
3873 p->p_crash_behavior_deadline = crash_behavior_deadline;
3874
3875 p->p_crash_count = px_sa.psa_crash_count;
3876 p->p_throttle_timeout = px_sa.psa_throttle_timeout;
3877
3878 /* We'll need the subsystem root for setting up Apple strings */
3879 imgp->ip_subsystem_root_path = p->p_subsystem_root_path;
3880
3881 context.vc_thread = imgp->ip_new_thread;
3882 context.vc_ucred = proc_ucred(p); /* XXX must NOT be kauth_cred_get() */
3883
3884 /*
3885 * Post fdt_fork(), pre exec_handle_sugid() - this is where we want
3886 * to handle the file_actions.
3887 */
3888
3889 /* Has spawn file actions? */
3890 if (imgp->ip_px_sfa != NULL) {
3891 /*
3892 * The POSIX_SPAWN_CLOEXEC_DEFAULT flag
3893 * is handled in exec_handle_file_actions().
3894 */
3895 #if CONFIG_AUDIT
3896 /*
3897 * The file actions auditing can overwrite the upath of
3898 * AUE_POSIX_SPAWN audit record. Save the audit record.
3899 */
3900 struct kaudit_record *save_uu_ar = uthread->uu_ar;
3901 uthread->uu_ar = NULL;
3902 #endif
3903 error = exec_handle_file_actions(imgp,
3904 imgp->ip_px_sa != NULL ? px_sa.psa_flags : 0);
3905 #if CONFIG_AUDIT
3906 /* Restore the AUE_POSIX_SPAWN audit record. */
3907 uthread->uu_ar = save_uu_ar;
3908 #endif
3909 if (error != 0) {
3910 goto bad;
3911 }
3912 }
3913
3914 /* Has spawn port actions? */
3915 if (imgp->ip_px_spa != NULL) {
3916 #if CONFIG_AUDIT
3917 /*
3918 * Do the same for the port actions as we did for the file
3919 * actions. Save the AUE_POSIX_SPAWN audit record.
3920 */
3921 struct kaudit_record *save_uu_ar = uthread->uu_ar;
3922 uthread->uu_ar = NULL;
3923 #endif
3924 error = exec_handle_port_actions(imgp, &port_actions);
3925 #if CONFIG_AUDIT
3926 /* Restore the AUE_POSIX_SPAWN audit record. */
3927 uthread->uu_ar = save_uu_ar;
3928 #endif
3929 if (error != 0) {
3930 goto bad;
3931 }
3932 }
3933
3934 /* Has spawn attr? */
3935 if (imgp->ip_px_sa != NULL) {
3936 /*
3937 * Reset UID/GID to parent's RUID/RGID; This works only
3938 * because the operation occurs before the call
3939 * to exec_handle_sugid() by the image activator called
3940 * from exec_activate_image().
3941 *
3942 * POSIX requires that any setuid/setgid bits on the process
3943 * image will take precedence over the spawn attributes
3944 * (re)setting them.
3945 *
3946 * Modifications to p_ucred must be guarded using the
3947 * proc's ucred lock. This prevents others from accessing
3948 * a garbage credential.
3949 */
3950 if (px_sa.psa_flags & POSIX_SPAWN_RESETIDS) {
3951 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred){
3952 return kauth_cred_setuidgid(my_cred,
3953 kauth_cred_getruid(my_cred),
3954 kauth_cred_getrgid(my_cred));
3955 });
3956 }
3957
3958 if (imgp->ip_px_pcred_info) {
3959 if (!spawn_no_exec) {
3960 error = ENOTSUP;
3961 goto bad;
3962 }
3963
3964 error = spawn_posix_cred_adopt(p, imgp->ip_px_pcred_info);
3965 if (error != 0) {
3966 goto bad;
3967 }
3968 }
3969
3970 #if CONFIG_PERSONAS
3971 if (imgp->ip_px_persona != NULL) {
3972 if (!spawn_no_exec) {
3973 error = ENOTSUP;
3974 goto bad;
3975 }
3976
3977 /*
3978 * If we were asked to spawn a process into a new persona,
3979 * do the credential switch now (which may override the UID/GID
3980 * inherit done just above). It's important to do this switch
3981 * before image activation both for reasons stated above, and
3982 * to ensure that the new persona has access to the image/file
3983 * being executed.
3984 */
3985 error = spawn_persona_adopt(p, imgp->ip_px_persona);
3986 if (error != 0) {
3987 goto bad;
3988 }
3989 }
3990 #endif /* CONFIG_PERSONAS */
3991 #if !SECURE_KERNEL
3992 /*
3993 * Disable ASLR for the spawned process.
3994 *
3995 * But only do so if we are not embedded + RELEASE.
3996 * While embedded allows for a boot-arg (-disable_aslr)
3997 * to deal with this (which itself is only honored on
3998 * DEVELOPMENT or DEBUG builds of xnu), it is often
3999 * useful or necessary to disable ASLR on a per-process
4000 * basis for unit testing and debugging.
4001 */
4002 if (px_sa.psa_flags & _POSIX_SPAWN_DISABLE_ASLR) {
4003 OSBitOrAtomic(P_DISABLE_ASLR, &p->p_flag);
4004 }
4005 #endif /* !SECURE_KERNEL */
4006
4007 /* Randomize high bits of ASLR slide */
4008 if (px_sa.psa_flags & _POSIX_SPAWN_HIGH_BITS_ASLR) {
4009 imgp->ip_flags |= IMGPF_HIGH_BITS_ASLR;
4010 }
4011
4012 #if !SECURE_KERNEL
4013 /*
4014 * Forcibly disallow execution from data pages for the spawned process
4015 * even if it would otherwise be permitted by the architecture default.
4016 */
4017 if (px_sa.psa_flags & _POSIX_SPAWN_ALLOW_DATA_EXEC) {
4018 imgp->ip_flags |= IMGPF_ALLOW_DATA_EXEC;
4019 }
4020 #endif /* !SECURE_KERNEL */
4021
4022 #if __has_feature(ptrauth_calls)
4023 if (vm_shared_region_reslide_aslr && is_64 && (px_sa.psa_flags & _POSIX_SPAWN_RESLIDE)) {
4024 imgp->ip_flags |= IMGPF_RESLIDE;
4025 }
4026 #endif /* __has_feature(ptrauth_calls) */
4027
4028 if ((px_sa.psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) ==
4029 POSIX_SPAWN_PROC_TYPE_DRIVER) {
4030 imgp->ip_flags |= IMGPF_DRIVER;
4031 }
4032 }
4033
4034 /*
4035 * Disable ASLR during image activation. This occurs either if the
4036 * _POSIX_SPAWN_DISABLE_ASLR attribute was found above or if
4037 * P_DISABLE_ASLR was inherited from the parent process.
4038 */
4039 if (p->p_flag & P_DISABLE_ASLR) {
4040 imgp->ip_flags |= IMGPF_DISABLE_ASLR;
4041 }
4042
4043 /*
4044 * Clear transition flag so we won't hang if exec_activate_image() causes
4045 * an automount (and launchd does a proc sysctl to service it).
4046 *
4047 * <rdar://problem/6848672>, <rdar://problem/5959568>.
4048 */
4049 proc_transend(p, 0);
4050 proc_transit_set = 0;
4051
4052 if (!spawn_no_exec) {
4053 /*
4054 * Clear the signal lock in case of exec, since
4055 * image activation uses psignal on child process.
4056 */
4057 proc_signalend(p, 0);
4058 proc_signal_set = 0;
4059 }
4060
4061 #if MAC_SPAWN /* XXX */
4062 if (uap->mac_p != USER_ADDR_NULL) {
4063 error = mac_execve_enter(uap->mac_p, imgp);
4064 if (error) {
4065 goto bad;
4066 }
4067 }
4068 #endif
4069
4070 /*
4071 * Activate the image.
4072 * Warning: If activation failed after point of no return, it returns error
4073 * as 0 and pretends the call succeeded.
4074 */
4075 error = exec_activate_image(imgp);
4076 #if defined(HAS_APPLE_PAC)
4077 ml_task_set_jop_pid_from_shared_region(new_task);
4078 ml_task_set_disable_user_jop(new_task, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
4079 ml_thread_set_disable_user_jop(imgp->ip_new_thread, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
4080 ml_thread_set_jop_pid(imgp->ip_new_thread, new_task);
4081 #endif
4082
4083 /*
4084 * If you've come here to add support for some new HW feature or some per-process or per-vmmap
4085 * or per-pmap flag that needs to be set before the process runs, or are in general lost, here
4086 * is some help. This summary was accurate as of Jul 2022. Use git log as needed. This comment
4087 * is here to prevent a recurrence of rdar://96307913
4088 *
4089 * In posix_spawn, following is what happens:
4090 * 1. Lots of prep and checking work
4091 * 2. Image activation via exec_activate_image(). The new task will get a new pmap here
4092 * 3. More prep work. (YOU ARE HERE)
4093 * 4. exec_resettextvp() is called
4094 * 5. At this point it is safe to check entitlements and code signatures
4095 * 6. task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
4096 * The new thread is allowed to run in kernel. It cannot yet get to userland
4097 * 7. More things done here. This is your chance to affect the task before it runs in
4098 * userspace
4099 * 8. task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
4100 * The new thread is allowed to run in userland
4101 */
4102
4103 if (error == 0 && !spawn_no_exec) {
4104 p = proc_exec_switch_task(current_proc(), p, old_task, new_task, imgp->ip_new_thread, &inherit);
4105 /* proc ref returned */
4106 should_release_proc_ref = TRUE;
4107 }
4108
4109 if (error == 0) {
4110 /* process completed the exec, but may have failed after point of no return */
4111 exec_done = TRUE;
4112 /*
4113 * Enable new task IPC access if exec_activate_image() returned an
4114 * active task. (Checks active bit in ipc_task_enable() under lock).
4115 */
4116 ipc_task_enable(new_task);
4117 }
4118
4119 if (!error && imgp->ip_px_sa != NULL) {
4120 thread_t child_thread = imgp->ip_new_thread;
4121 uthread_t child_uthread = get_bsdthread_info(child_thread);
4122
4123 /*
4124 * Because of POSIX_SPAWN_SETEXEC, we need to handle this after image
4125 * activation, else when image activation fails (before the point of no
4126 * return) would leave the parent process in a modified state.
4127 */
4128 if (px_sa.psa_flags & POSIX_SPAWN_SETPGROUP) {
4129 struct setpgid_args spga;
4130 spga.pid = proc_getpid(p);
4131 spga.pgid = px_sa.psa_pgroup;
4132 /*
4133 * Effectively, call setpgid() system call; works
4134 * because there are no pointer arguments.
4135 */
4136 if ((error = setpgid(p, &spga, ival)) != 0) {
4137 goto bad_px_sa;
4138 }
4139 }
4140
4141 if (px_sa.psa_flags & POSIX_SPAWN_SETSID) {
4142 error = setsid_internal(p);
4143 if (error != 0) {
4144 goto bad_px_sa;
4145 }
4146 }
4147
4148 /*
4149 * If we have a spawn attr, and it contains signal related flags,
4150 * the we need to process them in the "context" of the new child
4151 * process, so we have to process it following image activation,
4152 * prior to making the thread runnable in user space. This is
4153 * necessitated by some signal information being per-thread rather
4154 * than per-process, and we don't have the new allocation in hand
4155 * until after the image is activated.
4156 */
4157
4158 /*
4159 * Mask a list of signals, instead of them being unmasked, if
4160 * they were unmasked in the parent; note that some signals
4161 * are not maskable.
4162 */
4163 if (px_sa.psa_flags & POSIX_SPAWN_SETSIGMASK) {
4164 child_uthread->uu_sigmask = (px_sa.psa_sigmask & ~sigcantmask);
4165 }
4166 /*
4167 * Default a list of signals instead of ignoring them, if
4168 * they were ignored in the parent. Note that we pass
4169 * spawn_no_exec to setsigvec() to indicate that we called
4170 * fork1() and therefore do not need to call proc_signalstart()
4171 * internally.
4172 */
4173 if (px_sa.psa_flags & POSIX_SPAWN_SETSIGDEF) {
4174 vec.sa_handler = SIG_DFL;
4175 vec.sa_tramp = 0;
4176 vec.sa_mask = 0;
4177 vec.sa_flags = 0;
4178 for (sig = 1; sig < NSIG; sig++) {
4179 if (px_sa.psa_sigdefault & (1 << (sig - 1))) {
4180 error = setsigvec(p, child_thread, sig, &vec, spawn_no_exec);
4181 }
4182 }
4183 }
4184
4185 /*
4186 * Activate the CPU usage monitor, if requested. This is done via a task-wide, per-thread CPU
4187 * usage limit, which will generate a resource exceeded exception if any one thread exceeds the
4188 * limit.
4189 *
4190 * Userland gives us interval in seconds, and the kernel SPI expects nanoseconds.
4191 */
4192 if ((px_sa.psa_cpumonitor_percent != 0) && (px_sa.psa_cpumonitor_percent < UINT8_MAX)) {
4193 /*
4194 * Always treat a CPU monitor activation coming from spawn as entitled. Requiring
4195 * an entitlement to configure the monitor a certain way seems silly, since
4196 * whomever is turning it on could just as easily choose not to do so.
4197 */
4198 error = proc_set_task_ruse_cpu(proc_task(p),
4199 TASK_POLICY_RESOURCE_ATTRIBUTE_NOTIFY_EXC,
4200 (uint8_t)px_sa.psa_cpumonitor_percent,
4201 px_sa.psa_cpumonitor_interval * NSEC_PER_SEC,
4202 0, TRUE);
4203 }
4204
4205
4206 if (px_pcred_info &&
4207 (px_pcred_info->pspci_flags & POSIX_SPAWN_POSIX_CRED_LOGIN)) {
4208 /*
4209 * setlogin() must happen after setsid()
4210 */
4211 setlogin_internal(p, px_pcred_info->pspci_login);
4212 }
4213
4214 bad_px_sa:
4215 if (error != 0) {
4216 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
4217 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_PSATTR, 0, 0);
4218 exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_PSATTR);
4219 }
4220 }
4221
4222 bad:
4223
4224 if (error == 0) {
4225 /* reset delay idle sleep status if set */
4226 #if CONFIG_DELAY_IDLE_SLEEP
4227 if ((p->p_flag & P_DELAYIDLESLEEP) == P_DELAYIDLESLEEP) {
4228 OSBitAndAtomic(~((uint32_t)P_DELAYIDLESLEEP), &p->p_flag);
4229 }
4230 #endif /* CONFIG_DELAY_IDLE_SLEEP */
4231 /* upon successful spawn, re/set the proc control state */
4232 if (imgp->ip_px_sa != NULL) {
4233 switch (px_sa.psa_pcontrol) {
4234 case POSIX_SPAWN_PCONTROL_THROTTLE:
4235 p->p_pcaction = P_PCTHROTTLE;
4236 break;
4237 case POSIX_SPAWN_PCONTROL_SUSPEND:
4238 p->p_pcaction = P_PCSUSP;
4239 break;
4240 case POSIX_SPAWN_PCONTROL_KILL:
4241 p->p_pcaction = P_PCKILL;
4242 break;
4243 case POSIX_SPAWN_PCONTROL_NONE:
4244 default:
4245 p->p_pcaction = 0;
4246 break;
4247 }
4248 ;
4249 }
4250 exec_resettextvp(p, imgp);
4251
4252 #if CONFIG_MEMORYSTATUS
4253 /* Set jetsam priority for DriverKit processes */
4254 if (px_sa.psa_apptype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
4255 px_sa.psa_priority = JETSAM_PRIORITY_DRIVER_APPLE;
4256 }
4257
4258 /* Has jetsam attributes? */
4259 if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_SET)) {
4260 /*
4261 * With 2-level high-water-mark support, POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is no
4262 * longer relevant, as background limits are described via the inactive limit slots.
4263 *
4264 * That said, however, if the POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is passed in,
4265 * we attempt to mimic previous behavior by forcing the BG limit data into the
4266 * inactive/non-fatal mode and force the active slots to hold system_wide/fatal mode.
4267 */
4268
4269 if (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND) {
4270 memorystatus_update(p, px_sa.psa_priority, 0, FALSE, /* assertion priority */
4271 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY),
4272 TRUE,
4273 -1, TRUE,
4274 px_sa.psa_memlimit_inactive, FALSE);
4275 } else {
4276 memorystatus_update(p, px_sa.psa_priority, 0, FALSE, /* assertion priority */
4277 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY),
4278 TRUE,
4279 px_sa.psa_memlimit_active,
4280 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_ACTIVE_FATAL),
4281 px_sa.psa_memlimit_inactive,
4282 (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_INACTIVE_FATAL));
4283 }
4284 }
4285
4286 /* Has jetsam relaunch behavior? */
4287 if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK)) {
4288 /*
4289 * Launchd has passed in data indicating the behavior of this process in response to jetsam.
4290 * This data would be used by the jetsam subsystem to determine the position and protection
4291 * offered to this process on dirty -> clean transitions.
4292 */
4293 int relaunch_flags = P_MEMSTAT_RELAUNCH_UNKNOWN;
4294 switch (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MASK) {
4295 case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_LOW:
4296 relaunch_flags = P_MEMSTAT_RELAUNCH_LOW;
4297 break;
4298 case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_MED:
4299 relaunch_flags = P_MEMSTAT_RELAUNCH_MED;
4300 break;
4301 case POSIX_SPAWN_JETSAM_RELAUNCH_BEHAVIOR_HIGH:
4302 relaunch_flags = P_MEMSTAT_RELAUNCH_HIGH;
4303 break;
4304 default:
4305 break;
4306 }
4307 memorystatus_relaunch_flags_update(p, relaunch_flags);
4308 }
4309
4310 #endif /* CONFIG_MEMORYSTATUS */
4311 if (imgp->ip_px_sa != NULL && px_sa.psa_thread_limit > 0) {
4312 task_set_thread_limit(new_task, (uint16_t)px_sa.psa_thread_limit);
4313 }
4314
4315 #if CONFIG_PROC_RESOURCE_LIMITS
4316 if (imgp->ip_px_sa != NULL && (px_sa.psa_port_soft_limit > 0 || px_sa.psa_port_hard_limit > 0)) {
4317 task_set_port_space_limits(new_task, (uint32_t)px_sa.psa_port_soft_limit,
4318 (uint32_t)px_sa.psa_port_hard_limit);
4319 }
4320
4321 if (imgp->ip_px_sa != NULL && (px_sa.psa_filedesc_soft_limit > 0 || px_sa.psa_filedesc_hard_limit > 0)) {
4322 proc_set_filedesc_limits(p, (int)px_sa.psa_filedesc_soft_limit,
4323 (int)px_sa.psa_filedesc_hard_limit);
4324 }
4325 #endif /* CONFIG_PROC_RESOURCE_LIMITS */
4326
4327 /* Disable wakeup monitoring for DriverKit processes */
4328 if (px_sa.psa_apptype == POSIX_SPAWN_PROC_TYPE_DRIVER) {
4329 uint32_t flags = WAKEMON_DISABLE;
4330 task_wakeups_monitor_ctl(new_task, &flags, NULL);
4331 }
4332 }
4333
4334 /*
4335 * If we successfully called fork1() or cloneproc, we always need
4336 * to do this. This is because we come back from that call with
4337 * signals blocked in the child, and we have to unblock them, for exec
4338 * case they are unblocked before activation, but for true spawn case
4339 * we want to wait until after we've performed any spawn actions.
4340 * This has to happen before process_signature(), which uses psignal.
4341 */
4342 if (proc_transit_set) {
4343 proc_transend(p, 0);
4344 }
4345
4346 /*
4347 * Drop the signal lock on the child which was taken on our
4348 * behalf by forkproc()/cloneproc() to prevent signals being
4349 * received by the child in a partially constructed state.
4350 */
4351 if (proc_signal_set) {
4352 proc_signalend(p, 0);
4353 }
4354
4355 if (error == 0) {
4356 /*
4357 * We need to initialize the bank context behind the protection of
4358 * the proc_trans lock to prevent a race with exit. We can't do this during
4359 * exec_activate_image because task_bank_init checks entitlements that
4360 * aren't loaded until subsequent calls (including exec_resettextvp).
4361 */
4362 error = proc_transstart(p, 0, 0);
4363
4364 if (error == 0) {
4365 task_bank_init(new_task);
4366 proc_transend(p, 0);
4367 }
4368
4369 #if __arm64__
4370 proc_footprint_entitlement_hacks(p, new_task);
4371 #endif /* __arm64__ */
4372
4373 #if XNU_TARGET_OS_OSX
4374 #define SINGLE_JIT_ENTITLEMENT "com.apple.security.cs.single-jit"
4375 if (IOTaskHasEntitlement(new_task, SINGLE_JIT_ENTITLEMENT)) {
4376 vm_map_single_jit(get_task_map(new_task));
4377 }
4378 #endif /* XNU_TARGET_OS_OSX */
4379
4380 #if __has_feature(ptrauth_calls)
4381 task_set_pac_exception_fatal_flag(new_task);
4382 #endif /* __has_feature(ptrauth_calls) */
4383 }
4384
4385 /* Inherit task role from old task to new task for exec */
4386 if (error == 0 && !spawn_no_exec) {
4387 proc_inherit_task_role(new_task, old_task);
4388 }
4389
4390 #if CONFIG_ARCADE
4391 if (error == 0) {
4392 /*
4393 * Check to see if we need to trigger an arcade upcall AST now
4394 * that the vnode has been reset on the task.
4395 */
4396 arcade_prepare(new_task, imgp->ip_new_thread);
4397 }
4398 #endif /* CONFIG_ARCADE */
4399
4400 if (error == 0) {
4401 proc_apply_jit_and_vm_policies(imgp, p, new_task);
4402 }
4403
4404 /* Clear the initial wait on the thread before handling spawn policy */
4405 if (imgp && imgp->ip_new_thread) {
4406 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
4407 }
4408
4409 /*
4410 * Apply the spawnattr policy, apptype (which primes the task for importance donation),
4411 * and bind any portwatch ports to the new task.
4412 * This must be done after the exec so that the child's thread is ready,
4413 * and after the in transit state has been released, because priority is
4414 * dropped here so we need to be prepared for a potentially long preemption interval
4415 *
4416 * TODO: Consider splitting this up into separate phases
4417 */
4418 if (error == 0 && imgp->ip_px_sa != NULL) {
4419 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4420
4421 error = exec_handle_spawnattr_policy(p, imgp->ip_new_thread, psa->psa_apptype, psa->psa_qos_clamp,
4422 psa->psa_darwin_role, &port_actions);
4423 }
4424
4425 /* Transfer the turnstile watchport boost to new task if in exec */
4426 if (error == 0 && !spawn_no_exec) {
4427 task_transfer_turnstile_watchports(old_task, new_task, imgp->ip_new_thread);
4428 }
4429
4430 if (error == 0 && imgp->ip_px_sa != NULL) {
4431 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4432
4433 if (psa->psa_no_smt) {
4434 task_set_no_smt(new_task);
4435 }
4436 if (psa->psa_tecs) {
4437 task_set_tecs(new_task);
4438 }
4439 }
4440
4441 if (error == 0 && imgp->ip_px_sa != NULL) {
4442 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
4443
4444 if (psa->psa_options & PSA_OPTION_DATALESS_IOPOLICY) {
4445 struct _iopol_param_t iop_param = {
4446 .iop_scope = IOPOL_SCOPE_PROCESS,
4447 .iop_iotype = IOPOL_TYPE_VFS_MATERIALIZE_DATALESS_FILES,
4448 .iop_policy = psa->psa_dataless_iopolicy,
4449 };
4450 error = iopolicysys_vfs_materialize_dataless_files(p, IOPOL_CMD_SET, iop_param.iop_scope,
4451 iop_param.iop_policy, &iop_param);
4452 }
4453 }
4454
4455 if (error == 0) {
4456 /* Apply the main thread qos */
4457 thread_t main_thread = imgp->ip_new_thread;
4458 task_set_main_thread_qos(new_task, main_thread);
4459 }
4460
4461 /*
4462 * Release any ports we kept around for binding to the new task
4463 * We need to release the rights even if the posix_spawn has failed.
4464 */
4465 if (imgp->ip_px_spa != NULL) {
4466 exec_port_actions_destroy(&port_actions);
4467 }
4468
4469 /*
4470 * We have to delay operations which might throw a signal until after
4471 * the signals have been unblocked; however, we want that to happen
4472 * after exec_resettextvp() so that the textvp is correct when they
4473 * fire.
4474 */
4475 if (error == 0) {
4476 error = process_signature(p, imgp);
4477
4478 /*
4479 * Pay for our earlier safety; deliver the delayed signals from
4480 * the incomplete spawn process now that it's complete.
4481 */
4482 if (imgp != NULL && spawn_no_exec && (p->p_lflag & P_LTRACED)) {
4483 psignal_vfork(p, proc_task(p), imgp->ip_new_thread, SIGTRAP);
4484 }
4485
4486 if (error == 0 && !spawn_no_exec) {
4487 KDBG(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXEC),
4488 proc_getpid(p));
4489 }
4490 }
4491
4492 if (spawn_no_exec) {
4493 /* flag the 'fork' has occurred */
4494 proc_knote(p->p_pptr, NOTE_FORK | proc_getpid(p));
4495 }
4496
4497 /* flag exec has occurred, notify only if it has not failed due to FP Key error */
4498 if (!error && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
4499 proc_knote(p, NOTE_EXEC);
4500 }
4501
4502 if (imgp != NULL) {
4503 uthread_set_exec_data(current_uthread(), NULL);
4504 if (imgp->ip_vp) {
4505 vnode_put(imgp->ip_vp);
4506 }
4507 if (imgp->ip_scriptvp) {
4508 vnode_put(imgp->ip_scriptvp);
4509 }
4510 if (imgp->ip_strings) {
4511 execargs_free(imgp);
4512 }
4513 kfree_data(imgp->ip_px_sfa,
4514 px_args.file_actions_size);
4515 kfree_data(imgp->ip_px_spa,
4516 px_args.port_actions_size);
4517 #if CONFIG_PERSONAS
4518 kfree_data(imgp->ip_px_persona,
4519 px_args.persona_info_size);
4520 #endif
4521 kfree_data(imgp->ip_px_pcred_info,
4522 px_args.posix_cred_info_size);
4523
4524 if (subsystem_root_path != NULL) {
4525 zfree(ZV_NAMEI, subsystem_root_path);
4526 }
4527 #if CONFIG_MACF
4528 struct ip_px_smpx_s *px_s = &imgp->ip_px_smpx;
4529 kfree_data(px_s->array, px_args.mac_extensions_size);
4530 kfree_data(px_s->data, (vm_size_t)px_s->datalen);
4531
4532 if (imgp->ip_execlabelp) {
4533 mac_cred_label_free(imgp->ip_execlabelp);
4534 imgp->ip_execlabelp = NULL;
4535 }
4536 if (imgp->ip_scriptlabelp) {
4537 mac_vnode_label_free(imgp->ip_scriptlabelp);
4538 imgp->ip_scriptlabelp = NULL;
4539 }
4540 if (imgp->ip_cs_error != OS_REASON_NULL) {
4541 os_reason_free(imgp->ip_cs_error);
4542 imgp->ip_cs_error = OS_REASON_NULL;
4543 }
4544 if (imgp->ip_inherited_shared_region_id != NULL) {
4545 kfree_data(imgp->ip_inherited_shared_region_id,
4546 strlen(imgp->ip_inherited_shared_region_id) + 1);
4547 imgp->ip_inherited_shared_region_id = NULL;
4548 }
4549 #endif
4550 }
4551
4552 #if CONFIG_DTRACE
4553 if (spawn_no_exec) {
4554 /*
4555 * In the original DTrace reference implementation,
4556 * posix_spawn() was a libc routine that just
4557 * did vfork(2) then exec(2). Thus the proc::: probes
4558 * are very fork/exec oriented. The details of this
4559 * in-kernel implementation of posix_spawn() is different
4560 * (while producing the same process-observable effects)
4561 * particularly w.r.t. errors, and which thread/process
4562 * is constructing what on behalf of whom.
4563 */
4564 if (error) {
4565 DTRACE_PROC1(spawn__failure, int, error);
4566 } else {
4567 DTRACE_PROC(spawn__success);
4568 /*
4569 * Some DTrace scripts, e.g. newproc.d in
4570 * /usr/bin, rely on the the 'exec-success'
4571 * probe being fired in the child after the
4572 * new process image has been constructed
4573 * in order to determine the associated pid.
4574 *
4575 * So, even though the parent built the image
4576 * here, for compatibility, mark the new thread
4577 * so 'exec-success' fires on it as it leaves
4578 * the kernel.
4579 */
4580 dtrace_thread_didexec(imgp->ip_new_thread);
4581 }
4582 } else {
4583 if (error) {
4584 DTRACE_PROC1(exec__failure, int, error);
4585 } else {
4586 dtrace_thread_didexec(imgp->ip_new_thread);
4587 }
4588 }
4589
4590 if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
4591 (*dtrace_proc_waitfor_hook)(p);
4592 }
4593 #endif
4594
4595 #if CONFIG_AUDIT
4596 if (!error && AUDIT_ENABLED() && p) {
4597 /* Add the CDHash of the new process to the audit record */
4598 uint8_t *cdhash = cs_get_cdhash(p);
4599 if (cdhash) {
4600 AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
4601 }
4602 }
4603 #endif
4604
4605 /* terminate the new task if exec failed */
4606 if (new_task != NULL && task_is_exec_copy(new_task)) {
4607 task_terminate_internal(new_task);
4608 }
4609
4610 if (exec_failure_reason && !spawn_no_exec) {
4611 psignal_with_reason(p, SIGKILL, exec_failure_reason);
4612 exec_failure_reason = NULL;
4613 }
4614
4615 /* Return to both the parent and the child? */
4616 if (imgp != NULL && spawn_no_exec) {
4617 /*
4618 * If the parent wants the pid, copy it out
4619 */
4620 if (error == 0 && pid != USER_ADDR_NULL) {
4621 _Static_assert(sizeof(pid_t) == 4, "posix_spawn() assumes a 32-bit pid_t");
4622 bool aligned = (pid & 3) == 0;
4623 if (aligned) {
4624 (void)copyout_atomic32(proc_getpid(p), pid);
4625 } else {
4626 (void)suword(pid, proc_getpid(p));
4627 }
4628 }
4629 retval[0] = error;
4630
4631 /*
4632 * If we had an error, perform an internal reap ; this is
4633 * entirely safe, as we have a real process backing us.
4634 */
4635 if (error) {
4636 proc_list_lock();
4637 p->p_listflag |= P_LIST_DEADPARENT;
4638 proc_list_unlock();
4639 proc_lock(p);
4640 /* make sure no one else has killed it off... */
4641 if (p->p_stat != SZOMB && p->exit_thread == NULL) {
4642 p->exit_thread = current_thread();
4643 p->p_posix_spawn_failed = true;
4644 proc_unlock(p);
4645 exit1(p, 1, (int *)NULL);
4646 } else {
4647 /* someone is doing it for us; just skip it */
4648 proc_unlock(p);
4649 }
4650 }
4651 }
4652
4653 /*
4654 * Do not terminate the current task, if proc_exec_switch_task did not
4655 * switch the tasks, terminating the current task without the switch would
4656 * result in loosing the SIGKILL status.
4657 */
4658 if (task_did_exec(old_task)) {
4659 /* Terminate the current task, since exec will start in new task */
4660 task_terminate_internal(old_task);
4661 }
4662
4663 /* Release the thread ref returned by cloneproc/fork1 */
4664 if (imgp != NULL && imgp->ip_new_thread) {
4665 /* wake up the new thread */
4666 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
4667 thread_deallocate(imgp->ip_new_thread);
4668 imgp->ip_new_thread = NULL;
4669 }
4670
4671 /* Release the ref returned by cloneproc/fork1 */
4672 if (new_task) {
4673 task_deallocate(new_task);
4674 new_task = NULL;
4675 }
4676
4677 if (should_release_proc_ref) {
4678 proc_rele(p);
4679 }
4680
4681 kfree_type(typeof(*__spawn_data), __spawn_data);
4682
4683 if (inherit != NULL) {
4684 ipc_importance_release(inherit);
4685 }
4686
4687 assert(exec_failure_reason == NULL);
4688 return error;
4689 }
4690
4691 /*
4692 * proc_exec_switch_task
4693 *
4694 * Parameters: old_proc proc before exec
4695 * new_proc proc after exec
4696 * old_task task before exec
4697 * new_task task after exec
4698 * new_thread thread in new task
4699 * inherit resulting importance linkage
4700 *
4701 * Returns: proc.
4702 *
4703 * Note: The function will switch proc in pid hash from old proc to new proc.
4704 * The switch needs to happen after draining all proc refs and inside
4705 * a proc list lock. In the case of failure to switch the proc, which
4706 * might happen if the process received a SIGKILL or jetsam killed it,
4707 * it will make sure that the new tasks terminates. User proc ref returned
4708 * to caller.
4709 *
4710 * This function is called after point of no return, in the case
4711 * failure to switch, it will terminate the new task and swallow the
4712 * error and let the terminated process complete exec and die.
4713 */
4714 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)4715 proc_exec_switch_task(proc_t old_proc, proc_t new_proc, task_t old_task, task_t new_task, thread_t new_thread,
4716 void **inherit)
4717 {
4718 boolean_t task_active;
4719 boolean_t proc_active;
4720 boolean_t thread_active;
4721 boolean_t reparent_traced_child = FALSE;
4722 thread_t old_thread = current_thread();
4723
4724 thread_set_exec_promotion(old_thread);
4725 old_proc = proc_refdrain_will_exec(old_proc);
4726
4727 new_proc = proc_refdrain_will_exec(new_proc);
4728 /* extra proc ref returned to the caller */
4729
4730 assert(get_threadtask(new_thread) == new_task);
4731 task_active = task_is_active(new_task);
4732 proc_active = !(old_proc->p_lflag & P_LEXIT);
4733
4734 /* Check if the current thread is not aborted due to SIGKILL */
4735 thread_active = thread_is_active(old_thread);
4736
4737 /*
4738 * Do not switch the proc if the new task or proc is already terminated
4739 * as a result of error in exec past point of no return
4740 */
4741 if (proc_active && task_active && thread_active) {
4742 uthread_t new_uthread = get_bsdthread_info(new_thread);
4743 uthread_t old_uthread = current_uthread();
4744
4745 /* Clear dispatchqueue and workloop ast offset */
4746 new_proc->p_dispatchqueue_offset = 0;
4747 new_proc->p_dispatchqueue_serialno_offset = 0;
4748 new_proc->p_dispatchqueue_label_offset = 0;
4749 new_proc->p_return_to_kernel_offset = 0;
4750 new_proc->p_pthread_wq_quantum_offset = 0;
4751
4752 /* If old_proc is session leader, change the leader to new proc */
4753 session_replace_leader(old_proc, new_proc);
4754
4755 proc_lock(old_proc);
4756
4757 /* Copy the signal state, dtrace state and set bsd ast on new thread */
4758 act_set_astbsd(new_thread);
4759 new_uthread->uu_siglist |= old_uthread->uu_siglist;
4760 new_uthread->uu_siglist |= old_proc->p_siglist;
4761 new_uthread->uu_sigwait = old_uthread->uu_sigwait;
4762 new_uthread->uu_sigmask = old_uthread->uu_sigmask;
4763 new_uthread->uu_oldmask = old_uthread->uu_oldmask;
4764 new_uthread->uu_exit_reason = old_uthread->uu_exit_reason;
4765 #if CONFIG_DTRACE
4766 new_uthread->t_dtrace_sig = old_uthread->t_dtrace_sig;
4767 new_uthread->t_dtrace_stop = old_uthread->t_dtrace_stop;
4768 new_uthread->t_dtrace_resumepid = old_uthread->t_dtrace_resumepid;
4769 assert(new_uthread->t_dtrace_scratch == NULL);
4770 new_uthread->t_dtrace_scratch = old_uthread->t_dtrace_scratch;
4771
4772 old_uthread->t_dtrace_sig = 0;
4773 old_uthread->t_dtrace_stop = 0;
4774 old_uthread->t_dtrace_resumepid = 0;
4775 old_uthread->t_dtrace_scratch = NULL;
4776 #endif
4777
4778 #if CONFIG_PROC_UDATA_STORAGE
4779 new_proc->p_user_data = old_proc->p_user_data;
4780 #endif /* CONFIG_PROC_UDATA_STORAGE */
4781
4782 /* Copy the resource accounting info */
4783 thread_copy_resource_info(new_thread, current_thread());
4784
4785 /* Clear the exit reason and signal state on old thread */
4786 old_uthread->uu_exit_reason = NULL;
4787 old_uthread->uu_siglist = 0;
4788
4789 task_set_did_exec_flag(old_task);
4790 task_clear_exec_copy_flag(new_task);
4791
4792 task_copy_fields_for_exec(new_task, old_task);
4793
4794 /*
4795 * Need to transfer pending watch port boosts to the new task
4796 * while still making sure that the old task remains in the
4797 * importance linkage. Create an importance linkage from old task
4798 * to new task, then switch the task importance base of old task
4799 * and new task. After the switch the port watch boost will be
4800 * boosting the new task and new task will be donating importance
4801 * to old task.
4802 */
4803 *inherit = ipc_importance_exec_switch_task(old_task, new_task);
4804
4805 /* Transfer parent's ptrace state to child */
4806 new_proc->p_lflag &= ~(P_LTRACED | P_LSIGEXC | P_LNOATTACH);
4807 new_proc->p_lflag |= (old_proc->p_lflag & (P_LTRACED | P_LSIGEXC | P_LNOATTACH));
4808 new_proc->p_oppid = old_proc->p_oppid;
4809
4810 if (old_proc->p_pptr != new_proc->p_pptr) {
4811 reparent_traced_child = TRUE;
4812 new_proc->p_lflag |= P_LTRACE_WAIT;
4813 }
4814
4815 proc_unlock(old_proc);
4816
4817 /* Update the list of proc knotes */
4818 proc_transfer_knotes(old_proc, new_proc);
4819
4820 /* Update the proc interval timers */
4821 proc_inherit_itimers(old_proc, new_proc);
4822
4823 proc_list_lock();
4824
4825 /* Insert the new proc in child list of parent proc */
4826 p_reparentallchildren(old_proc, new_proc);
4827
4828 /* Switch proc in pid hash */
4829 phash_replace_locked(old_proc, new_proc);
4830
4831 /* Transfer the shadow flag to old proc */
4832 os_atomic_andnot(&new_proc->p_refcount, P_REF_SHADOW, relaxed);
4833 os_atomic_or(&old_proc->p_refcount, P_REF_SHADOW, relaxed);
4834
4835 /* Change init proc if launchd exec */
4836 if (old_proc == initproc) {
4837 /* Take the ref on new proc after proc_refwake_did_exec */
4838 initproc = new_proc;
4839 /* Drop the proc ref on old proc */
4840 proc_rele(old_proc);
4841 }
4842
4843 proc_list_unlock();
4844 } else {
4845 task_terminate_internal(new_task);
4846 }
4847
4848 proc_refwake_did_exec(new_proc);
4849 proc_refwake_did_exec(old_proc);
4850
4851 /* Take a ref on initproc if it changed */
4852 if (new_proc == initproc) {
4853 initproc = proc_ref(new_proc, false);
4854 assert(initproc != PROC_NULL);
4855 }
4856
4857 thread_clear_exec_promotion(old_thread);
4858 proc_rele(old_proc);
4859
4860 if (reparent_traced_child) {
4861 proc_t pp = proc_parent(old_proc);
4862 assert(pp != PROC_NULL);
4863
4864 proc_reparentlocked(new_proc, pp, 1, 0);
4865 proc_rele(pp);
4866
4867 proc_lock(new_proc);
4868 new_proc->p_lflag &= ~P_LTRACE_WAIT;
4869 proc_unlock(new_proc);
4870 }
4871
4872 return new_proc;
4873 }
4874
4875 /*
4876 * execve
4877 *
4878 * Parameters: uap->fname File name to exec
4879 * uap->argp Argument list
4880 * uap->envp Environment list
4881 *
4882 * Returns: 0 Success
4883 * __mac_execve:EINVAL Invalid argument
4884 * __mac_execve:ENOTSUP Invalid argument
4885 * __mac_execve:EACCES Permission denied
4886 * __mac_execve:EINTR Interrupted function
4887 * __mac_execve:ENOMEM Not enough space
4888 * __mac_execve:EFAULT Bad address
4889 * __mac_execve:ENAMETOOLONG Filename too long
4890 * __mac_execve:ENOEXEC Executable file format error
4891 * __mac_execve:ETXTBSY Text file busy [misuse of error code]
4892 * __mac_execve:???
4893 *
4894 * TODO: Dynamic linker header address on stack is copied via suword()
4895 */
4896 /* ARGSUSED */
4897 int
execve(proc_t p,struct execve_args * uap,int32_t * retval)4898 execve(proc_t p, struct execve_args *uap, int32_t *retval)
4899 {
4900 struct __mac_execve_args muap;
4901 int err;
4902
4903 memoryshot(VM_EXECVE, DBG_FUNC_NONE);
4904
4905 muap.fname = uap->fname;
4906 muap.argp = uap->argp;
4907 muap.envp = uap->envp;
4908 muap.mac_p = USER_ADDR_NULL;
4909 err = __mac_execve(p, &muap, retval);
4910
4911 return err;
4912 }
4913
4914 /*
4915 * __mac_execve
4916 *
4917 * Parameters: uap->fname File name to exec
4918 * uap->argp Argument list
4919 * uap->envp Environment list
4920 * uap->mac_p MAC label supplied by caller
4921 *
4922 * Returns: 0 Success
4923 * EINVAL Invalid argument
4924 * ENOTSUP Not supported
4925 * ENOEXEC Executable file format error
4926 * exec_activate_image:EINVAL Invalid argument
4927 * exec_activate_image:EACCES Permission denied
4928 * exec_activate_image:EINTR Interrupted function
4929 * exec_activate_image:ENOMEM Not enough space
4930 * exec_activate_image:EFAULT Bad address
4931 * exec_activate_image:ENAMETOOLONG Filename too long
4932 * exec_activate_image:ENOEXEC Executable file format error
4933 * exec_activate_image:ETXTBSY Text file busy [misuse of error code]
4934 * exec_activate_image:EBADEXEC The executable is corrupt/unknown
4935 * exec_activate_image:???
4936 * mac_execve_enter:???
4937 *
4938 * TODO: Dynamic linker header address on stack is copied via suword()
4939 */
4940 int
__mac_execve(proc_t p,struct __mac_execve_args * uap,int32_t * retval __unused)4941 __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval __unused)
4942 {
4943 struct image_params *imgp = NULL;
4944 struct vnode_attr *vap = NULL;
4945 struct vnode_attr *origvap = NULL;
4946 int error;
4947 int is_64 = IS_64BIT_PROCESS(p);
4948 struct vfs_context context;
4949 struct uthread *uthread = NULL;
4950 task_t old_task = current_task();
4951 task_t new_task = NULL;
4952 boolean_t should_release_proc_ref = FALSE;
4953 boolean_t exec_done = FALSE;
4954 void *inherit = NULL;
4955 struct {
4956 struct image_params imgp;
4957 struct vnode_attr va;
4958 struct vnode_attr origva;
4959 } *__execve_data;
4960
4961 /* Allocate a big chunk for locals instead of using stack since these
4962 * structures a pretty big.
4963 */
4964 __execve_data = kalloc_type(typeof(*__execve_data), Z_WAITOK | Z_ZERO);
4965 if (__execve_data == NULL) {
4966 error = ENOMEM;
4967 goto exit_with_error;
4968 }
4969 imgp = &__execve_data->imgp;
4970 vap = &__execve_data->va;
4971 origvap = &__execve_data->origva;
4972
4973 /* Initialize the common data in the image_params structure */
4974 imgp->ip_user_fname = uap->fname;
4975 imgp->ip_user_argv = uap->argp;
4976 imgp->ip_user_envv = uap->envp;
4977 imgp->ip_vattr = vap;
4978 imgp->ip_origvattr = origvap;
4979 imgp->ip_vfs_context = &context;
4980 imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT_ADDR : IMGPF_NONE) | ((p->p_flag & P_DISABLE_ASLR) ? IMGPF_DISABLE_ASLR : IMGPF_NONE);
4981 imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
4982 imgp->ip_mac_return = 0;
4983 imgp->ip_cs_error = OS_REASON_NULL;
4984 imgp->ip_simulator_binary = IMGPF_SB_DEFAULT;
4985 imgp->ip_subsystem_root_path = NULL;
4986 uthread_set_exec_data(current_uthread(), imgp);
4987
4988 #if CONFIG_MACF
4989 if (uap->mac_p != USER_ADDR_NULL) {
4990 error = mac_execve_enter(uap->mac_p, imgp);
4991 if (error) {
4992 goto exit_with_error;
4993 }
4994 }
4995 #endif
4996 uthread = current_uthread();
4997 {
4998 imgp->ip_flags |= IMGPF_EXEC;
4999
5000 /* Adjust the user proc count */
5001 (void)chgproccnt(kauth_getruid(), 1);
5002 /*
5003 * For execve case, create a new proc, task and thread
5004 * but don't make the proc visible to userland. After
5005 * image activation, the new proc would take place of
5006 * the old proc in pid hash and other lists that make
5007 * the proc visible to the system.
5008 */
5009 imgp->ip_new_thread = cloneproc(old_task, NULL, p, CLONEPROC_FLAGS_FOR_EXEC);
5010 /* task and thread ref returned by cloneproc */
5011 if (imgp->ip_new_thread == NULL) {
5012 (void)chgproccnt(kauth_getruid(), -1);
5013 error = ENOMEM;
5014 goto exit_with_error;
5015 }
5016
5017 new_task = get_threadtask(imgp->ip_new_thread);
5018 }
5019
5020 p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
5021
5022 context.vc_thread = imgp->ip_new_thread;
5023 context.vc_ucred = kauth_cred_proc_ref(p); /* XXX must NOT be kauth_cred_get() */
5024
5025 imgp->ip_subsystem_root_path = p->p_subsystem_root_path;
5026
5027 proc_transend(p, 0);
5028 proc_signalend(p, 0);
5029
5030 /*
5031 * Activate the image.
5032 * Warning: If activation failed after point of no return, it returns error
5033 * as 0 and pretends the call succeeded.
5034 */
5035 error = exec_activate_image(imgp);
5036 /* thread and task ref returned for vfexec case */
5037
5038 if (imgp->ip_new_thread != NULL) {
5039 /*
5040 * task reference might be returned by exec_activate_image
5041 * for vfexec.
5042 */
5043 new_task = get_threadtask(imgp->ip_new_thread);
5044 #if defined(HAS_APPLE_PAC)
5045 ml_task_set_disable_user_jop(new_task, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
5046 ml_thread_set_disable_user_jop(imgp->ip_new_thread, imgp->ip_flags & IMGPF_NOJOP ? TRUE : FALSE);
5047 #endif
5048 }
5049
5050 if (!error) {
5051 p = proc_exec_switch_task(current_proc(), p, old_task, new_task, imgp->ip_new_thread, &inherit);
5052 /* proc ref returned */
5053 should_release_proc_ref = TRUE;
5054 }
5055
5056 kauth_cred_unref(&context.vc_ucred);
5057
5058 if (!error) {
5059 exec_done = TRUE;
5060 assert(imgp->ip_new_thread != NULL);
5061 /*
5062 * Enable new task IPC access if exec_activate_image() returned an
5063 * active task. (Checks active bit in ipc_task_enable() under lock).
5064 */
5065 ipc_task_enable(new_task);
5066
5067 exec_resettextvp(p, imgp);
5068 error = process_signature(p, imgp);
5069 }
5070
5071 #if defined(HAS_APPLE_PAC)
5072 if (imgp->ip_new_thread && !error) {
5073 ml_task_set_jop_pid_from_shared_region(new_task);
5074 ml_thread_set_jop_pid(imgp->ip_new_thread, new_task);
5075 }
5076 #endif /* defined(HAS_APPLE_PAC) */
5077
5078 /* flag exec has occurred, notify only if it has not failed due to FP Key error */
5079 if (exec_done && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) {
5080 proc_knote(p, NOTE_EXEC);
5081 }
5082
5083 if (imgp->ip_vp != NULLVP) {
5084 vnode_put(imgp->ip_vp);
5085 }
5086 if (imgp->ip_scriptvp != NULLVP) {
5087 vnode_put(imgp->ip_scriptvp);
5088 }
5089 if (imgp->ip_strings) {
5090 execargs_free(imgp);
5091 }
5092 #if CONFIG_MACF
5093 if (imgp->ip_execlabelp) {
5094 mac_cred_label_free(imgp->ip_execlabelp);
5095 imgp->ip_execlabelp = NULL;
5096 }
5097 if (imgp->ip_scriptlabelp) {
5098 mac_vnode_label_free(imgp->ip_scriptlabelp);
5099 imgp->ip_scriptlabelp = NULL;
5100 }
5101 #endif
5102 if (imgp->ip_cs_error != OS_REASON_NULL) {
5103 os_reason_free(imgp->ip_cs_error);
5104 imgp->ip_cs_error = OS_REASON_NULL;
5105 }
5106
5107 if (!error) {
5108 /*
5109 * We need to initialize the bank context behind the protection of
5110 * the proc_trans lock to prevent a race with exit. We can't do this during
5111 * exec_activate_image because task_bank_init checks entitlements that
5112 * aren't loaded until subsequent calls (including exec_resettextvp).
5113 */
5114 error = proc_transstart(p, 0, 0);
5115 }
5116
5117 if (!error) {
5118 task_bank_init(new_task);
5119 proc_transend(p, 0);
5120
5121 // Don't inherit crash behavior across exec
5122 p->p_crash_behavior = 0;
5123 p->p_crash_behavior_deadline = 0;
5124
5125 #if __arm64__
5126 proc_footprint_entitlement_hacks(p, new_task);
5127 #endif /* __arm64__ */
5128
5129 #if XNU_TARGET_OS_OSX
5130 if (IOTaskHasEntitlement(new_task, SINGLE_JIT_ENTITLEMENT)) {
5131 vm_map_single_jit(get_task_map(new_task));
5132 }
5133 #endif /* XNU_TARGET_OS_OSX */
5134
5135 /* Sever any extant thread affinity */
5136 thread_affinity_exec(current_thread());
5137
5138 /* Inherit task role from old task to new task for exec */
5139 proc_inherit_task_role(new_task, old_task);
5140
5141 thread_t main_thread = imgp->ip_new_thread;
5142
5143 task_set_main_thread_qos(new_task, main_thread);
5144
5145 #if __has_feature(ptrauth_calls)
5146 task_set_pac_exception_fatal_flag(new_task);
5147 #endif /* __has_feature(ptrauth_calls) */
5148
5149 #if CONFIG_ARCADE
5150 /*
5151 * Check to see if we need to trigger an arcade upcall AST now
5152 * that the vnode has been reset on the task.
5153 */
5154 arcade_prepare(new_task, imgp->ip_new_thread);
5155 #endif /* CONFIG_ARCADE */
5156
5157 proc_apply_jit_and_vm_policies(imgp, p, new_task);
5158
5159 if (vm_darkwake_mode == TRUE) {
5160 /*
5161 * This process is being launched when the system
5162 * is in darkwake. So mark it specially. This will
5163 * cause all its pages to be entered in the background Q.
5164 */
5165 task_set_darkwake_mode(new_task, vm_darkwake_mode);
5166 }
5167
5168 #if CONFIG_DTRACE
5169 dtrace_thread_didexec(imgp->ip_new_thread);
5170
5171 if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) {
5172 (*dtrace_proc_waitfor_hook)(p);
5173 }
5174 #endif
5175
5176 #if CONFIG_AUDIT
5177 if (!error && AUDIT_ENABLED() && p) {
5178 /* Add the CDHash of the new process to the audit record */
5179 uint8_t *cdhash = cs_get_cdhash(p);
5180 if (cdhash) {
5181 AUDIT_ARG(data, cdhash, sizeof(uint8_t), CS_CDHASH_LEN);
5182 }
5183 }
5184 #endif
5185 } else {
5186 DTRACE_PROC1(exec__failure, int, error);
5187 }
5188
5189 exit_with_error:
5190
5191 /* terminate the new task it if exec failed */
5192 if (new_task != NULL && task_is_exec_copy(new_task)) {
5193 task_terminate_internal(new_task);
5194 }
5195
5196 if (imgp != NULL) {
5197 /* Clear the initial wait on the thread transferring watchports */
5198 if (imgp->ip_new_thread) {
5199 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_INITIAL_WAIT);
5200 }
5201
5202 /* Transfer the watchport boost to new task */
5203 if (!error) {
5204 task_transfer_turnstile_watchports(old_task,
5205 new_task, imgp->ip_new_thread);
5206 }
5207 /*
5208 * Do not terminate the current task, if proc_exec_switch_task did not
5209 * switch the tasks, terminating the current task without the switch would
5210 * result in loosing the SIGKILL status.
5211 */
5212 if (task_did_exec(old_task)) {
5213 /* Terminate the current task, since exec will start in new task */
5214 task_terminate_internal(old_task);
5215 }
5216
5217 /* Release the thread ref returned by cloneproc */
5218 if (imgp->ip_new_thread) {
5219 /* wake up the new exec thread */
5220 task_clear_return_wait(get_threadtask(imgp->ip_new_thread), TCRW_CLEAR_FINAL_WAIT);
5221 thread_deallocate(imgp->ip_new_thread);
5222 imgp->ip_new_thread = NULL;
5223 }
5224 }
5225
5226 /* Release the ref returned by fork_create_child */
5227 if (new_task) {
5228 task_deallocate(new_task);
5229 new_task = NULL;
5230 }
5231
5232 if (should_release_proc_ref) {
5233 proc_rele(p);
5234 }
5235
5236 uthread_set_exec_data(current_uthread(), NULL);
5237 kfree_type(typeof(*__execve_data), __execve_data);
5238
5239 if (inherit != NULL) {
5240 ipc_importance_release(inherit);
5241 }
5242
5243 return error;
5244 }
5245
5246
5247 /*
5248 * copyinptr
5249 *
5250 * Description: Copy a pointer in from user space to a user_addr_t in kernel
5251 * space, based on 32/64 bitness of the user space
5252 *
5253 * Parameters: froma User space address
5254 * toptr Address of kernel space user_addr_t
5255 * ptr_size 4/8, based on 'froma' address space
5256 *
5257 * Returns: 0 Success
5258 * EFAULT Bad 'froma'
5259 *
5260 * Implicit returns:
5261 * *ptr_size Modified
5262 */
5263 static int
copyinptr(user_addr_t froma,user_addr_t * toptr,int ptr_size)5264 copyinptr(user_addr_t froma, user_addr_t *toptr, int ptr_size)
5265 {
5266 int error;
5267
5268 if (ptr_size == 4) {
5269 /* 64 bit value containing 32 bit address */
5270 unsigned int i = 0;
5271
5272 error = copyin(froma, &i, 4);
5273 *toptr = CAST_USER_ADDR_T(i); /* SAFE */
5274 } else {
5275 error = copyin(froma, toptr, 8);
5276 }
5277 return error;
5278 }
5279
5280
5281 /*
5282 * copyoutptr
5283 *
5284 * Description: Copy a pointer out from a user_addr_t in kernel space to
5285 * user space, based on 32/64 bitness of the user space
5286 *
5287 * Parameters: ua User space address to copy to
5288 * ptr Address of kernel space user_addr_t
5289 * ptr_size 4/8, based on 'ua' address space
5290 *
5291 * Returns: 0 Success
5292 * EFAULT Bad 'ua'
5293 *
5294 */
5295 static int
copyoutptr(user_addr_t ua,user_addr_t ptr,int ptr_size)5296 copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size)
5297 {
5298 int error;
5299
5300 if (ptr_size == 4) {
5301 /* 64 bit value containing 32 bit address */
5302 unsigned int i = CAST_DOWN_EXPLICIT(unsigned int, ua); /* SAFE */
5303
5304 error = copyout(&i, ptr, 4);
5305 } else {
5306 error = copyout(&ua, ptr, 8);
5307 }
5308 return error;
5309 }
5310
5311
5312 /*
5313 * exec_copyout_strings
5314 *
5315 * Copy out the strings segment to user space. The strings segment is put
5316 * on a preinitialized stack frame.
5317 *
5318 * Parameters: struct image_params * the image parameter block
5319 * int * a pointer to the stack offset variable
5320 *
5321 * Returns: 0 Success
5322 * !0 Faiure: errno
5323 *
5324 * Implicit returns:
5325 * (*stackp) The stack offset, modified
5326 *
5327 * Note: The strings segment layout is backward, from the beginning
5328 * of the top of the stack to consume the minimal amount of
5329 * space possible; the returned stack pointer points to the
5330 * end of the area consumed (stacks grow downward).
5331 *
5332 * argc is an int; arg[i] are pointers; env[i] are pointers;
5333 * the 0's are (void *)NULL's
5334 *
5335 * The stack frame layout is:
5336 *
5337 * +-------------+ <- p->user_stack
5338 * | 16b |
5339 * +-------------+
5340 * | STRING AREA |
5341 * | : |
5342 * | : |
5343 * | : |
5344 * +- -- -- -- --+
5345 * | PATH AREA |
5346 * +-------------+
5347 * | 0 |
5348 * +-------------+
5349 * | applev[n] |
5350 * +-------------+
5351 * :
5352 * :
5353 * +-------------+
5354 * | applev[1] |
5355 * +-------------+
5356 * | exec_path / |
5357 * | applev[0] |
5358 * +-------------+
5359 * | 0 |
5360 * +-------------+
5361 * | env[n] |
5362 * +-------------+
5363 * :
5364 * :
5365 * +-------------+
5366 * | env[0] |
5367 * +-------------+
5368 * | 0 |
5369 * +-------------+
5370 * | arg[argc-1] |
5371 * +-------------+
5372 * :
5373 * :
5374 * +-------------+
5375 * | arg[0] |
5376 * +-------------+
5377 * | argc |
5378 * sp-> +-------------+
5379 *
5380 * Although technically a part of the STRING AREA, we treat the PATH AREA as
5381 * a separate entity. This allows us to align the beginning of the PATH AREA
5382 * to a pointer boundary so that the exec_path, env[i], and argv[i] pointers
5383 * which preceed it on the stack are properly aligned.
5384 */
5385 __attribute__((noinline))
5386 static int
exec_copyout_strings(struct image_params * imgp,user_addr_t * stackp)5387 exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp)
5388 {
5389 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
5390 int ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
5391 int ptr_area_size;
5392 void *ptr_buffer_start, *ptr_buffer;
5393 size_t string_size;
5394
5395 user_addr_t string_area; /* *argv[], *env[] */
5396 user_addr_t ptr_area; /* argv[], env[], applev[] */
5397 user_addr_t argc_area; /* argc */
5398 user_addr_t stack;
5399 int error;
5400
5401 unsigned i;
5402 struct copyout_desc {
5403 char *start_string;
5404 int count;
5405 #if CONFIG_DTRACE
5406 user_addr_t *dtrace_cookie;
5407 #endif
5408 boolean_t null_term;
5409 } descriptors[] = {
5410 {
5411 .start_string = imgp->ip_startargv,
5412 .count = imgp->ip_argc,
5413 #if CONFIG_DTRACE
5414 .dtrace_cookie = &p->p_dtrace_argv,
5415 #endif
5416 .null_term = TRUE
5417 },
5418 {
5419 .start_string = imgp->ip_endargv,
5420 .count = imgp->ip_envc,
5421 #if CONFIG_DTRACE
5422 .dtrace_cookie = &p->p_dtrace_envp,
5423 #endif
5424 .null_term = TRUE
5425 },
5426 {
5427 .start_string = imgp->ip_strings,
5428 .count = 1,
5429 #if CONFIG_DTRACE
5430 .dtrace_cookie = NULL,
5431 #endif
5432 .null_term = FALSE
5433 },
5434 {
5435 .start_string = imgp->ip_endenvv,
5436 .count = imgp->ip_applec - 1, /* exec_path handled above */
5437 #if CONFIG_DTRACE
5438 .dtrace_cookie = NULL,
5439 #endif
5440 .null_term = TRUE
5441 }
5442 };
5443
5444 stack = *stackp;
5445
5446 /*
5447 * All previous contributors to the string area
5448 * should have aligned their sub-area
5449 */
5450 if (imgp->ip_strspace % ptr_size != 0) {
5451 error = EINVAL;
5452 goto bad;
5453 }
5454
5455 /* Grow the stack down for the strings we've been building up */
5456 string_size = imgp->ip_strendp - imgp->ip_strings;
5457 stack -= string_size;
5458 string_area = stack;
5459
5460 /*
5461 * Need room for one pointer for each string, plus
5462 * one for the NULLs terminating the argv, envv, and apple areas.
5463 */
5464 ptr_area_size = (imgp->ip_argc + imgp->ip_envc + imgp->ip_applec + 3) * ptr_size;
5465 stack -= ptr_area_size;
5466 ptr_area = stack;
5467
5468 /* We'll construct all the pointer arrays in our string buffer,
5469 * which we already know is aligned properly, and ip_argspace
5470 * was used to verify we have enough space.
5471 */
5472 ptr_buffer_start = ptr_buffer = (void *)imgp->ip_strendp;
5473
5474 /*
5475 * Need room for pointer-aligned argc slot.
5476 */
5477 stack -= ptr_size;
5478 argc_area = stack;
5479
5480 /*
5481 * Record the size of the arguments area so that sysctl_procargs()
5482 * can return the argument area without having to parse the arguments.
5483 */
5484 proc_lock(p);
5485 p->p_argc = imgp->ip_argc;
5486 p->p_argslen = (int)(*stackp - string_area);
5487 proc_unlock(p);
5488
5489 /* Return the initial stack address: the location of argc */
5490 *stackp = stack;
5491
5492 /*
5493 * Copy out the entire strings area.
5494 */
5495 error = copyout(imgp->ip_strings, string_area,
5496 string_size);
5497 if (error) {
5498 goto bad;
5499 }
5500
5501 for (i = 0; i < sizeof(descriptors) / sizeof(descriptors[0]); i++) {
5502 char *cur_string = descriptors[i].start_string;
5503 int j;
5504
5505 #if CONFIG_DTRACE
5506 if (descriptors[i].dtrace_cookie) {
5507 proc_lock(p);
5508 *descriptors[i].dtrace_cookie = ptr_area + ((uintptr_t)ptr_buffer - (uintptr_t)ptr_buffer_start); /* dtrace convenience */
5509 proc_unlock(p);
5510 }
5511 #endif /* CONFIG_DTRACE */
5512
5513 /*
5514 * For each segment (argv, envv, applev), copy as many pointers as requested
5515 * to our pointer buffer.
5516 */
5517 for (j = 0; j < descriptors[i].count; j++) {
5518 user_addr_t cur_address = string_area + (cur_string - imgp->ip_strings);
5519
5520 /* Copy out the pointer to the current string. Alignment has been verified */
5521 if (ptr_size == 8) {
5522 *(uint64_t *)ptr_buffer = (uint64_t)cur_address;
5523 } else {
5524 *(uint32_t *)ptr_buffer = (uint32_t)cur_address;
5525 }
5526
5527 ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
5528 cur_string += strlen(cur_string) + 1; /* Only a NUL between strings in the same area */
5529 }
5530
5531 if (descriptors[i].null_term) {
5532 if (ptr_size == 8) {
5533 *(uint64_t *)ptr_buffer = 0ULL;
5534 } else {
5535 *(uint32_t *)ptr_buffer = 0;
5536 }
5537
5538 ptr_buffer = (void *)((uintptr_t)ptr_buffer + ptr_size);
5539 }
5540 }
5541
5542 /*
5543 * Copy out all our pointer arrays in bulk.
5544 */
5545 error = copyout(ptr_buffer_start, ptr_area,
5546 ptr_area_size);
5547 if (error) {
5548 goto bad;
5549 }
5550
5551 /* argc (int32, stored in a ptr_size area) */
5552 error = copyoutptr((user_addr_t)imgp->ip_argc, argc_area, ptr_size);
5553 if (error) {
5554 goto bad;
5555 }
5556
5557 bad:
5558 return error;
5559 }
5560
5561
5562 /*
5563 * exec_extract_strings
5564 *
5565 * Copy arguments and environment from user space into work area; we may
5566 * have already copied some early arguments into the work area, and if
5567 * so, any arguments opied in are appended to those already there.
5568 * This function is the primary manipulator of ip_argspace, since
5569 * these are the arguments the client of execve(2) knows about. After
5570 * each argv[]/envv[] string is copied, we charge the string length
5571 * and argv[]/envv[] pointer slot to ip_argspace, so that we can
5572 * full preflight the arg list size.
5573 *
5574 * Parameters: struct image_params * the image parameter block
5575 *
5576 * Returns: 0 Success
5577 * !0 Failure: errno
5578 *
5579 * Implicit returns;
5580 * (imgp->ip_argc) Count of arguments, updated
5581 * (imgp->ip_envc) Count of environment strings, updated
5582 * (imgp->ip_argspace) Count of remaining of NCARGS
5583 * (imgp->ip_interp_buffer) Interpreter and args (mutated in place)
5584 *
5585 *
5586 * Note: The argument and environment vectors are user space pointers
5587 * to arrays of user space pointers.
5588 */
5589 __attribute__((noinline))
5590 static int
exec_extract_strings(struct image_params * imgp)5591 exec_extract_strings(struct image_params *imgp)
5592 {
5593 int error = 0;
5594 int ptr_size = (imgp->ip_flags & IMGPF_WAS_64BIT_ADDR) ? 8 : 4;
5595 int new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
5596 user_addr_t argv = imgp->ip_user_argv;
5597 user_addr_t envv = imgp->ip_user_envv;
5598
5599 /*
5600 * Adjust space reserved for the path name by however much padding it
5601 * needs. Doing this here since we didn't know if this would be a 32-
5602 * or 64-bit process back in exec_save_path.
5603 */
5604 while (imgp->ip_strspace % new_ptr_size != 0) {
5605 *imgp->ip_strendp++ = '\0';
5606 imgp->ip_strspace--;
5607 /* imgp->ip_argspace--; not counted towards exec args total */
5608 }
5609
5610 /*
5611 * From now on, we start attributing string space to ip_argspace
5612 */
5613 imgp->ip_startargv = imgp->ip_strendp;
5614 imgp->ip_argc = 0;
5615
5616 if ((imgp->ip_flags & IMGPF_INTERPRET) != 0) {
5617 user_addr_t arg;
5618 char *argstart, *ch;
5619
5620 /* First, the arguments in the "#!" string are tokenized and extracted. */
5621 argstart = imgp->ip_interp_buffer;
5622 while (argstart) {
5623 ch = argstart;
5624 while (*ch && !IS_WHITESPACE(*ch)) {
5625 ch++;
5626 }
5627
5628 if (*ch == '\0') {
5629 /* last argument, no need to NUL-terminate */
5630 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
5631 argstart = NULL;
5632 } else {
5633 /* NUL-terminate */
5634 *ch = '\0';
5635 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(argstart), UIO_SYSSPACE, TRUE);
5636
5637 /*
5638 * Find the next string. We know spaces at the end of the string have already
5639 * been stripped.
5640 */
5641 argstart = ch + 1;
5642 while (IS_WHITESPACE(*argstart)) {
5643 argstart++;
5644 }
5645 }
5646
5647 /* Error-check, regardless of whether this is the last interpreter arg or not */
5648 if (error) {
5649 goto bad;
5650 }
5651 if (imgp->ip_argspace < new_ptr_size) {
5652 error = E2BIG;
5653 goto bad;
5654 }
5655 imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
5656 imgp->ip_argc++;
5657 }
5658
5659 if (argv != 0LL) {
5660 /*
5661 * If we are running an interpreter, replace the av[0] that was
5662 * passed to execve() with the path name that was
5663 * passed to execve() for interpreters which do not use the PATH
5664 * to locate their script arguments.
5665 */
5666 error = copyinptr(argv, &arg, ptr_size);
5667 if (error) {
5668 goto bad;
5669 }
5670 if (arg != 0LL) {
5671 argv += ptr_size; /* consume without using */
5672 }
5673 }
5674
5675 if (imgp->ip_interp_sugid_fd != -1) {
5676 char temp[19]; /* "/dev/fd/" + 10 digits + NUL */
5677 snprintf(temp, sizeof(temp), "/dev/fd/%d", imgp->ip_interp_sugid_fd);
5678 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(temp), UIO_SYSSPACE, TRUE);
5679 } else {
5680 error = exec_add_user_string(imgp, imgp->ip_user_fname, imgp->ip_seg, TRUE);
5681 }
5682
5683 if (error) {
5684 goto bad;
5685 }
5686 if (imgp->ip_argspace < new_ptr_size) {
5687 error = E2BIG;
5688 goto bad;
5689 }
5690 imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
5691 imgp->ip_argc++;
5692 }
5693
5694 while (argv != 0LL) {
5695 user_addr_t arg;
5696
5697 error = copyinptr(argv, &arg, ptr_size);
5698 if (error) {
5699 goto bad;
5700 }
5701
5702 if (arg == 0LL) {
5703 break;
5704 }
5705
5706 argv += ptr_size;
5707
5708 /*
5709 * av[n...] = arg[n]
5710 */
5711 error = exec_add_user_string(imgp, arg, imgp->ip_seg, TRUE);
5712 if (error) {
5713 goto bad;
5714 }
5715 if (imgp->ip_argspace < new_ptr_size) {
5716 error = E2BIG;
5717 goto bad;
5718 }
5719 imgp->ip_argspace -= new_ptr_size; /* to hold argv[] entry */
5720 imgp->ip_argc++;
5721 }
5722
5723 /* Save space for argv[] NULL terminator */
5724 if (imgp->ip_argspace < new_ptr_size) {
5725 error = E2BIG;
5726 goto bad;
5727 }
5728 imgp->ip_argspace -= new_ptr_size;
5729
5730 /* Note where the args ends and env begins. */
5731 imgp->ip_endargv = imgp->ip_strendp;
5732 imgp->ip_envc = 0;
5733
5734 /* Now, get the environment */
5735 while (envv != 0LL) {
5736 user_addr_t env;
5737
5738 error = copyinptr(envv, &env, ptr_size);
5739 if (error) {
5740 goto bad;
5741 }
5742
5743 envv += ptr_size;
5744 if (env == 0LL) {
5745 break;
5746 }
5747 /*
5748 * av[n...] = env[n]
5749 */
5750 error = exec_add_user_string(imgp, env, imgp->ip_seg, TRUE);
5751 if (error) {
5752 goto bad;
5753 }
5754 if (imgp->ip_argspace < new_ptr_size) {
5755 error = E2BIG;
5756 goto bad;
5757 }
5758 imgp->ip_argspace -= new_ptr_size; /* to hold envv[] entry */
5759 imgp->ip_envc++;
5760 }
5761
5762 /* Save space for envv[] NULL terminator */
5763 if (imgp->ip_argspace < new_ptr_size) {
5764 error = E2BIG;
5765 goto bad;
5766 }
5767 imgp->ip_argspace -= new_ptr_size;
5768
5769 /* Align the tail of the combined argv+envv area */
5770 while (imgp->ip_strspace % new_ptr_size != 0) {
5771 if (imgp->ip_argspace < 1) {
5772 error = E2BIG;
5773 goto bad;
5774 }
5775 *imgp->ip_strendp++ = '\0';
5776 imgp->ip_strspace--;
5777 imgp->ip_argspace--;
5778 }
5779
5780 /* Note where the envv ends and applev begins. */
5781 imgp->ip_endenvv = imgp->ip_strendp;
5782
5783 /*
5784 * From now on, we are no longer charging argument
5785 * space to ip_argspace.
5786 */
5787
5788 bad:
5789 return error;
5790 }
5791
5792 /*
5793 * Libc has an 8-element array set up for stack guard values. It only fills
5794 * in one of those entries, and both gcc and llvm seem to use only a single
5795 * 8-byte guard. Until somebody needs more than an 8-byte guard value, don't
5796 * do the work to construct them.
5797 */
5798 #define GUARD_VALUES 1
5799 #define GUARD_KEY "stack_guard="
5800
5801 /*
5802 * System malloc needs some entropy when it is initialized.
5803 */
5804 #define ENTROPY_VALUES 2
5805 #define ENTROPY_KEY "malloc_entropy="
5806
5807 /*
5808 * libplatform needs a random pointer-obfuscation value when it is initialized.
5809 */
5810 #define PTR_MUNGE_VALUES 1
5811 #define PTR_MUNGE_KEY "ptr_munge="
5812
5813 /*
5814 * System malloc engages nanozone for UIAPP.
5815 */
5816 #define NANO_ENGAGE_KEY "MallocNanoZone=1"
5817
5818 /*
5819 * System malloc uses deferred reclaim
5820 * for UIAPP on embedded systems with swap.
5821 */
5822 #define RECLAIM_ENGAGE_KEY "MallocDeferredReclaim=1"
5823 /*
5824 * Used to pass experiment flags up to libmalloc.
5825 */
5826 #define LIBMALLOC_EXPERIMENT_FACTORS_KEY "MallocExperiment="
5827
5828 #define PFZ_KEY "pfz="
5829 extern user32_addr_t commpage_text32_location;
5830 extern user64_addr_t commpage_text64_location;
5831
5832 extern uuid_string_t bootsessionuuid_string;
5833
5834 #define MAIN_STACK_VALUES 4
5835 #define MAIN_STACK_KEY "main_stack="
5836
5837 #define FSID_KEY "executable_file="
5838 #define DYLD_FSID_KEY "dyld_file="
5839 #define CDHASH_KEY "executable_cdhash="
5840 #define DYLD_FLAGS_KEY "dyld_flags="
5841 #define SUBSYSTEM_ROOT_PATH_KEY "subsystem_root_path="
5842 #define APP_BOOT_SESSION_KEY "executable_boothash="
5843 #if __has_feature(ptrauth_calls)
5844 #define PTRAUTH_DISABLED_FLAG "ptrauth_disabled=1"
5845 #define DYLD_ARM64E_ABI_KEY "arm64e_abi="
5846 #endif /* __has_feature(ptrauth_calls) */
5847 #define MAIN_TH_PORT_KEY "th_port="
5848
5849 #define FSID_MAX_STRING "0x1234567890abcdef,0x1234567890abcdef"
5850
5851 #define HEX_STR_LEN 18 // 64-bit hex value "0x0123456701234567"
5852 #define HEX_STR_LEN32 10 // 32-bit hex value "0x01234567"
5853
5854 #if XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES
5855 #define VM_FORCE_4K_PAGES_KEY "vm_force_4k_pages=1"
5856 #endif /* XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES */
5857
5858 static int
exec_add_entropy_key(struct image_params * imgp,const char * key,int values,boolean_t embedNUL)5859 exec_add_entropy_key(struct image_params *imgp,
5860 const char *key,
5861 int values,
5862 boolean_t embedNUL)
5863 {
5864 const int limit = 8;
5865 uint64_t entropy[limit];
5866 char str[strlen(key) + (HEX_STR_LEN + 1) * limit + 1];
5867 if (values > limit) {
5868 values = limit;
5869 }
5870
5871 read_random(entropy, sizeof(entropy[0]) * values);
5872
5873 if (embedNUL) {
5874 entropy[0] &= ~(0xffull << 8);
5875 }
5876
5877 int len = scnprintf(str, sizeof(str), "%s0x%llx", key, entropy[0]);
5878 size_t remaining = sizeof(str) - len;
5879 for (int i = 1; i < values && remaining > 0; ++i) {
5880 size_t start = sizeof(str) - remaining;
5881 len = scnprintf(&str[start], remaining, ",0x%llx", entropy[i]);
5882 remaining -= len;
5883 }
5884
5885 return exec_add_user_string(imgp, CAST_USER_ADDR_T(str), UIO_SYSSPACE, FALSE);
5886 }
5887
5888 /*
5889 * Build up the contents of the apple[] string vector
5890 */
5891 #if (DEVELOPMENT || DEBUG)
5892 extern uint64_t dyld_flags;
5893 #endif
5894
5895 #if __has_feature(ptrauth_calls)
5896 static inline bool
is_arm64e_running_as_arm64(const struct image_params * imgp)5897 is_arm64e_running_as_arm64(const struct image_params *imgp)
5898 {
5899 return (imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
5900 (imgp->ip_flags & IMGPF_NOJOP);
5901 }
5902 #endif /* __has_feature(ptrauth_calls) */
5903
5904 _Atomic uint64_t libmalloc_experiment_factors = 0;
5905
5906 static int
exec_add_apple_strings(struct image_params * imgp,const load_result_t * load_result)5907 exec_add_apple_strings(struct image_params *imgp,
5908 const load_result_t *load_result)
5909 {
5910 int error;
5911 int img_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) ? 8 : 4;
5912 thread_t new_thread;
5913 ipc_port_t sright;
5914 uint64_t local_experiment_factors = 0;
5915
5916 /* exec_save_path stored the first string */
5917 imgp->ip_applec = 1;
5918
5919 /* adding the pfz string */
5920 {
5921 char pfz_string[strlen(PFZ_KEY) + HEX_STR_LEN + 1];
5922
5923 if (img_ptr_size == 8) {
5924 __assert_only size_t ret = snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%llx", commpage_text64_location);
5925 assert(ret < sizeof(pfz_string));
5926 } else {
5927 snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%x", commpage_text32_location);
5928 }
5929 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(pfz_string), UIO_SYSSPACE, FALSE);
5930 if (error) {
5931 printf("Failed to add the pfz string with error %d\n", error);
5932 goto bad;
5933 }
5934 imgp->ip_applec++;
5935 }
5936
5937 /* adding the NANO_ENGAGE_KEY key */
5938 if (imgp->ip_px_sa) {
5939 struct _posix_spawnattr* psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
5940 int proc_flags = psa->psa_flags;
5941
5942 if ((proc_flags & _POSIX_SPAWN_NANO_ALLOCATOR) == _POSIX_SPAWN_NANO_ALLOCATOR) {
5943 const char *nano_string = NANO_ENGAGE_KEY;
5944 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(nano_string), UIO_SYSSPACE, FALSE);
5945 if (error) {
5946 goto bad;
5947 }
5948 imgp->ip_applec++;
5949 }
5950 #if CONFIG_JETSAM && CONFIG_MEMORYSTATUS && CONFIG_DEFERRED_RECLAIM
5951 if (memorystatus_swap_all_apps) {
5952 int psa_apptype = psa->psa_apptype;
5953
5954 if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) == POSIX_SPAWN_PROC_TYPE_APP_DEFAULT) {
5955 const char *reclaim_string = RECLAIM_ENGAGE_KEY;
5956 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(reclaim_string), UIO_SYSSPACE, FALSE);
5957 if (error) {
5958 goto bad;
5959 }
5960 imgp->ip_applec++;
5961 }
5962 }
5963 #endif /* CONFIG_JETSAM && CONFIG_MEMORYSTATUS && CONFIG_DEFERRED_RECLAIM */
5964 }
5965
5966 /*
5967 * Supply libc with a collection of random values to use when
5968 * implementing -fstack-protector.
5969 *
5970 * (The first random string always contains an embedded NUL so that
5971 * __stack_chk_guard also protects against C string vulnerabilities)
5972 */
5973 error = exec_add_entropy_key(imgp, GUARD_KEY, GUARD_VALUES, TRUE);
5974 if (error) {
5975 goto bad;
5976 }
5977 imgp->ip_applec++;
5978
5979 /*
5980 * Supply libc with entropy for system malloc.
5981 */
5982 error = exec_add_entropy_key(imgp, ENTROPY_KEY, ENTROPY_VALUES, FALSE);
5983 if (error) {
5984 goto bad;
5985 }
5986 imgp->ip_applec++;
5987
5988 /*
5989 * Supply libpthread & libplatform with a random value to use for pointer
5990 * obfuscation.
5991 */
5992 error = exec_add_entropy_key(imgp, PTR_MUNGE_KEY, PTR_MUNGE_VALUES, FALSE);
5993 if (error) {
5994 goto bad;
5995 }
5996 imgp->ip_applec++;
5997
5998 /*
5999 * Add MAIN_STACK_KEY: Supplies the address and size of the main thread's
6000 * stack if it was allocated by the kernel.
6001 *
6002 * The guard page is not included in this stack size as libpthread
6003 * expects to add it back in after receiving this value.
6004 */
6005 if (load_result->unixproc) {
6006 char stack_string[strlen(MAIN_STACK_KEY) + (HEX_STR_LEN + 1) * MAIN_STACK_VALUES + 1];
6007 snprintf(stack_string, sizeof(stack_string),
6008 MAIN_STACK_KEY "0x%llx,0x%llx,0x%llx,0x%llx",
6009 (uint64_t)load_result->user_stack,
6010 (uint64_t)load_result->user_stack_size,
6011 (uint64_t)load_result->user_stack_alloc,
6012 (uint64_t)load_result->user_stack_alloc_size);
6013 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(stack_string), UIO_SYSSPACE, FALSE);
6014 if (error) {
6015 goto bad;
6016 }
6017 imgp->ip_applec++;
6018 }
6019
6020 if (imgp->ip_vattr) {
6021 uint64_t fsid = vnode_get_va_fsid(imgp->ip_vattr);
6022 uint64_t fsobjid = imgp->ip_vattr->va_fileid;
6023
6024 char fsid_string[strlen(FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
6025 snprintf(fsid_string, sizeof(fsid_string),
6026 FSID_KEY "0x%llx,0x%llx", fsid, fsobjid);
6027 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
6028 if (error) {
6029 goto bad;
6030 }
6031 imgp->ip_applec++;
6032 }
6033
6034 if (imgp->ip_dyld_fsid || imgp->ip_dyld_fsobjid) {
6035 char fsid_string[strlen(DYLD_FSID_KEY) + strlen(FSID_MAX_STRING) + 1];
6036 snprintf(fsid_string, sizeof(fsid_string),
6037 DYLD_FSID_KEY "0x%llx,0x%llx", imgp->ip_dyld_fsid, imgp->ip_dyld_fsobjid);
6038 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE);
6039 if (error) {
6040 goto bad;
6041 }
6042 imgp->ip_applec++;
6043 }
6044
6045 uint8_t cdhash[SHA1_RESULTLEN];
6046 int cdhash_errror = ubc_cs_getcdhash(imgp->ip_vp, imgp->ip_arch_offset, cdhash);
6047 if (cdhash_errror == 0) {
6048 char hash_string[strlen(CDHASH_KEY) + 2 * SHA1_RESULTLEN + 1];
6049 strncpy(hash_string, CDHASH_KEY, sizeof(hash_string));
6050 char *p = hash_string + sizeof(CDHASH_KEY) - 1;
6051 for (int i = 0; i < SHA1_RESULTLEN; i++) {
6052 snprintf(p, 3, "%02x", (int) cdhash[i]);
6053 p += 2;
6054 }
6055 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(hash_string), UIO_SYSSPACE, FALSE);
6056 if (error) {
6057 goto bad;
6058 }
6059 imgp->ip_applec++;
6060
6061 /* hash together cd-hash and boot-session-uuid */
6062 uint8_t sha_digest[SHA256_DIGEST_LENGTH];
6063 SHA256_CTX sha_ctx;
6064 SHA256_Init(&sha_ctx);
6065 SHA256_Update(&sha_ctx, bootsessionuuid_string, sizeof(bootsessionuuid_string));
6066 SHA256_Update(&sha_ctx, cdhash, sizeof(cdhash));
6067 SHA256_Final(sha_digest, &sha_ctx);
6068 char app_boot_string[strlen(APP_BOOT_SESSION_KEY) + 2 * SHA1_RESULTLEN + 1];
6069 strncpy(app_boot_string, APP_BOOT_SESSION_KEY, sizeof(app_boot_string));
6070 char *s = app_boot_string + sizeof(APP_BOOT_SESSION_KEY) - 1;
6071 for (int i = 0; i < SHA1_RESULTLEN; i++) {
6072 snprintf(s, 3, "%02x", (int) sha_digest[i]);
6073 s += 2;
6074 }
6075 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(app_boot_string), UIO_SYSSPACE, FALSE);
6076 if (error) {
6077 goto bad;
6078 }
6079 imgp->ip_applec++;
6080 }
6081 #if (DEVELOPMENT || DEBUG)
6082 if (dyld_flags) {
6083 char dyld_flags_string[strlen(DYLD_FLAGS_KEY) + HEX_STR_LEN + 1];
6084 snprintf(dyld_flags_string, sizeof(dyld_flags_string), DYLD_FLAGS_KEY "0x%llx", dyld_flags);
6085 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_flags_string), UIO_SYSSPACE, FALSE);
6086 if (error) {
6087 goto bad;
6088 }
6089 imgp->ip_applec++;
6090 }
6091 #endif
6092 if (imgp->ip_subsystem_root_path) {
6093 size_t buffer_len = MAXPATHLEN + strlen(SUBSYSTEM_ROOT_PATH_KEY);
6094 char subsystem_root_path_string[buffer_len];
6095 int required_len = snprintf(subsystem_root_path_string, buffer_len, SUBSYSTEM_ROOT_PATH_KEY "%s", imgp->ip_subsystem_root_path);
6096
6097 if (((size_t)required_len >= buffer_len) || (required_len < 0)) {
6098 error = ENAMETOOLONG;
6099 goto bad;
6100 }
6101
6102 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(subsystem_root_path_string), UIO_SYSSPACE, FALSE);
6103 if (error) {
6104 goto bad;
6105 }
6106
6107 imgp->ip_applec++;
6108 }
6109 #if __has_feature(ptrauth_calls)
6110 if (is_arm64e_running_as_arm64(imgp)) {
6111 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(PTRAUTH_DISABLED_FLAG), UIO_SYSSPACE, FALSE);
6112 if (error) {
6113 goto bad;
6114 }
6115
6116 imgp->ip_applec++;
6117 }
6118 #endif /* __has_feature(ptrauth_calls) */
6119
6120
6121 #if __has_feature(ptrauth_calls) && defined(XNU_TARGET_OS_OSX)
6122 {
6123 char dyld_abi_string[strlen(DYLD_ARM64E_ABI_KEY) + 8];
6124 strlcpy(dyld_abi_string, DYLD_ARM64E_ABI_KEY, sizeof(dyld_abi_string));
6125 bool allowAll = bootarg_arm64e_preview_abi;
6126 strlcat(dyld_abi_string, (allowAll ? "all" : "os"), sizeof(dyld_abi_string));
6127 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_abi_string), UIO_SYSSPACE, FALSE);
6128 if (error) {
6129 goto bad;
6130 }
6131
6132 imgp->ip_applec++;
6133 }
6134 #endif
6135 /*
6136 * Add main thread mach port name
6137 * +1 uref on main thread port, this ref will be extracted by libpthread in __pthread_init
6138 * and consumed in _bsdthread_terminate. Leaking the main thread port name if not linked
6139 * against libpthread.
6140 */
6141 if ((new_thread = imgp->ip_new_thread) != THREAD_NULL) {
6142 thread_reference(new_thread);
6143 sright = convert_thread_to_port_pinned(new_thread);
6144 task_t new_task = get_threadtask(new_thread);
6145 mach_port_name_t name = ipc_port_copyout_send(sright, get_task_ipcspace(new_task));
6146 char port_name_hex_str[strlen(MAIN_TH_PORT_KEY) + HEX_STR_LEN32 + 1];
6147 snprintf(port_name_hex_str, sizeof(port_name_hex_str), MAIN_TH_PORT_KEY "0x%x", name);
6148
6149 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(port_name_hex_str), UIO_SYSSPACE, FALSE);
6150 if (error) {
6151 goto bad;
6152 }
6153 imgp->ip_applec++;
6154 }
6155
6156 #if XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES
6157 if (imgp->ip_px_sa != NULL) {
6158 struct _posix_spawnattr* psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
6159 if (psa->psa_flags & _POSIX_SPAWN_FORCE_4K_PAGES) {
6160 const char *vm_force_4k_string = VM_FORCE_4K_PAGES_KEY;
6161 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(vm_force_4k_string), UIO_SYSSPACE, FALSE);
6162 if (error) {
6163 goto bad;
6164 }
6165 imgp->ip_applec++;
6166 }
6167 }
6168 #endif /* XNU_TARGET_OS_OSX && _POSIX_SPAWN_FORCE_4K_PAGES && PMAP_CREATE_FORCE_4K_PAGES */
6169
6170 /* adding the libmalloc experiment string */
6171 local_experiment_factors = os_atomic_load_wide(&libmalloc_experiment_factors, relaxed);
6172 if (__improbable(local_experiment_factors != 0)) {
6173 char libmalloc_experiment_factors_string[strlen(LIBMALLOC_EXPERIMENT_FACTORS_KEY) + HEX_STR_LEN + 1];
6174
6175 snprintf(
6176 libmalloc_experiment_factors_string,
6177 sizeof(libmalloc_experiment_factors_string),
6178 LIBMALLOC_EXPERIMENT_FACTORS_KEY "0x%llx",
6179 local_experiment_factors);
6180 error = exec_add_user_string(
6181 imgp,
6182 CAST_USER_ADDR_T(libmalloc_experiment_factors_string),
6183 UIO_SYSSPACE,
6184 FALSE);
6185 if (error) {
6186 printf("Failed to add the libmalloc experiment factors string with error %d\n", error);
6187 goto bad;
6188 }
6189 imgp->ip_applec++;
6190 }
6191
6192 /* tell dyld that it can leverage hardware for its read-only/read-write trusted path */
6193 if (imgp->ip_flags & IMGPF_HW_TPRO) {
6194 const char *dyld_hw_tpro = "dyld_hw_tpro=1";
6195 error = exec_add_user_string(imgp, CAST_USER_ADDR_T(dyld_hw_tpro), UIO_SYSSPACE, FALSE);
6196 if (error) {
6197 printf("Failed to add dyld hw tpro setting with error %d\n", error);
6198 goto bad;
6199 }
6200
6201 imgp->ip_applec++;
6202 }
6203
6204 /* Align the tail of the combined applev area */
6205 while (imgp->ip_strspace % img_ptr_size != 0) {
6206 *imgp->ip_strendp++ = '\0';
6207 imgp->ip_strspace--;
6208 }
6209
6210 bad:
6211 return error;
6212 }
6213
6214 /*
6215 * exec_check_permissions
6216 *
6217 * Description: Verify that the file that is being attempted to be executed
6218 * is in fact allowed to be executed based on it POSIX file
6219 * permissions and other access control criteria
6220 *
6221 * Parameters: struct image_params * the image parameter block
6222 *
6223 * Returns: 0 Success
6224 * EACCES Permission denied
6225 * ENOEXEC Executable file format error
6226 * ETXTBSY Text file busy [misuse of error code]
6227 * vnode_getattr:???
6228 * vnode_authorize:???
6229 */
6230 static int
exec_check_permissions(struct image_params * imgp)6231 exec_check_permissions(struct image_params *imgp)
6232 {
6233 struct vnode *vp = imgp->ip_vp;
6234 struct vnode_attr *vap = imgp->ip_vattr;
6235 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
6236 int error;
6237 kauth_action_t action;
6238
6239 /* Only allow execution of regular files */
6240 if (!vnode_isreg(vp)) {
6241 return EACCES;
6242 }
6243
6244 /* Get the file attributes that we will be using here and elsewhere */
6245 VATTR_INIT(vap);
6246 VATTR_WANTED(vap, va_uid);
6247 VATTR_WANTED(vap, va_gid);
6248 VATTR_WANTED(vap, va_mode);
6249 VATTR_WANTED(vap, va_fsid);
6250 VATTR_WANTED(vap, va_fsid64);
6251 VATTR_WANTED(vap, va_fileid);
6252 VATTR_WANTED(vap, va_data_size);
6253 if ((error = vnode_getattr(vp, vap, imgp->ip_vfs_context)) != 0) {
6254 return error;
6255 }
6256
6257 /*
6258 * Ensure that at least one execute bit is on - otherwise root
6259 * will always succeed, and we don't want to happen unless the
6260 * file really is executable.
6261 */
6262 if (!vfs_authopaque(vnode_mount(vp)) && ((vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)) {
6263 return EACCES;
6264 }
6265
6266 /* Disallow zero length files */
6267 if (vap->va_data_size == 0) {
6268 return ENOEXEC;
6269 }
6270
6271 imgp->ip_arch_offset = (user_size_t)0;
6272 #if __LP64__
6273 imgp->ip_arch_size = vap->va_data_size;
6274 #else
6275 if (vap->va_data_size > UINT32_MAX) {
6276 return ENOEXEC;
6277 }
6278 imgp->ip_arch_size = (user_size_t)vap->va_data_size;
6279 #endif
6280
6281 /* Disable setuid-ness for traced programs or if MNT_NOSUID */
6282 if ((vp->v_mount->mnt_flag & MNT_NOSUID) || (p->p_lflag & P_LTRACED)) {
6283 vap->va_mode &= ~(VSUID | VSGID);
6284 }
6285
6286 /*
6287 * Disable _POSIX_SPAWN_ALLOW_DATA_EXEC and _POSIX_SPAWN_DISABLE_ASLR
6288 * flags for setuid/setgid binaries.
6289 */
6290 if (vap->va_mode & (VSUID | VSGID)) {
6291 imgp->ip_flags &= ~(IMGPF_ALLOW_DATA_EXEC | IMGPF_DISABLE_ASLR);
6292 }
6293
6294 #if CONFIG_MACF
6295 error = mac_vnode_check_exec(imgp->ip_vfs_context, vp, imgp);
6296 if (error) {
6297 return error;
6298 }
6299 #endif
6300
6301 /* Check for execute permission */
6302 action = KAUTH_VNODE_EXECUTE;
6303 /* Traced images must also be readable */
6304 if (p->p_lflag & P_LTRACED) {
6305 action |= KAUTH_VNODE_READ_DATA;
6306 }
6307 if ((error = vnode_authorize(vp, NULL, action, imgp->ip_vfs_context)) != 0) {
6308 return error;
6309 }
6310
6311 #if 0
6312 /* Don't let it run if anyone had it open for writing */
6313 vnode_lock(vp);
6314 if (vp->v_writecount) {
6315 panic("going to return ETXTBSY %x", vp);
6316 vnode_unlock(vp);
6317 return ETXTBSY;
6318 }
6319 vnode_unlock(vp);
6320 #endif
6321
6322 /* XXX May want to indicate to underlying FS that vnode is open */
6323
6324 return error;
6325 }
6326
6327
6328 /*
6329 * exec_handle_sugid
6330 *
6331 * Initially clear the P_SUGID in the process flags; if an SUGID process is
6332 * exec'ing a non-SUGID image, then this is the point of no return.
6333 *
6334 * If the image being activated is SUGID, then replace the credential with a
6335 * copy, disable tracing (unless the tracing process is root), reset the
6336 * mach task port to revoke it, set the P_SUGID bit,
6337 *
6338 * If the saved user and group ID will be changing, then make sure it happens
6339 * to a new credential, rather than a shared one.
6340 *
6341 * Set the security token (this is probably obsolete, given that the token
6342 * should not technically be separate from the credential itself).
6343 *
6344 * Parameters: struct image_params * the image parameter block
6345 *
6346 * Returns: void No failure indication
6347 *
6348 * Implicit returns:
6349 * <process credential> Potentially modified/replaced
6350 * <task port> Potentially revoked
6351 * <process flags> P_SUGID bit potentially modified
6352 * <security token> Potentially modified
6353 */
6354 __attribute__((noinline))
6355 static int
exec_handle_sugid(struct image_params * imgp)6356 exec_handle_sugid(struct image_params *imgp)
6357 {
6358 proc_t p = vfs_context_proc(imgp->ip_vfs_context);
6359 kauth_cred_t cred = vfs_context_ucred(imgp->ip_vfs_context);
6360 int i;
6361 int leave_sugid_clear = 0;
6362 int mac_reset_ipc = 0;
6363 int error = 0;
6364 task_t task = NULL;
6365 #if CONFIG_MACF
6366 int mac_transition, disjoint_cred = 0;
6367 int label_update_return = 0;
6368
6369 /*
6370 * Determine whether a call to update the MAC label will result in the
6371 * credential changing.
6372 *
6373 * Note: MAC policies which do not actually end up modifying
6374 * the label subsequently are strongly encouraged to
6375 * return 0 for this check, since a non-zero answer will
6376 * slow down the exec fast path for normal binaries.
6377 */
6378 mac_transition = mac_cred_check_label_update_execve(
6379 imgp->ip_vfs_context,
6380 imgp->ip_vp,
6381 imgp->ip_arch_offset,
6382 imgp->ip_scriptvp,
6383 imgp->ip_scriptlabelp,
6384 imgp->ip_execlabelp,
6385 p,
6386 &imgp->ip_px_smpx);
6387 #endif
6388
6389 OSBitAndAtomic(~((uint32_t)P_SUGID), &p->p_flag);
6390
6391 /*
6392 * Order of the following is important; group checks must go last,
6393 * as we use the success of the 'ismember' check combined with the
6394 * failure of the explicit match to indicate that we will be setting
6395 * the egid of the process even though the new process did not
6396 * require VSUID/VSGID bits in order for it to set the new group as
6397 * its egid.
6398 *
6399 * Note: Technically, by this we are implying a call to
6400 * setegid() in the new process, rather than implying
6401 * it used its VSGID bit to set the effective group,
6402 * even though there is no code in that process to make
6403 * such a call.
6404 */
6405 if (((imgp->ip_origvattr->va_mode & VSUID) != 0 &&
6406 kauth_cred_getuid(cred) != imgp->ip_origvattr->va_uid) ||
6407 ((imgp->ip_origvattr->va_mode & VSGID) != 0 &&
6408 ((kauth_cred_ismember_gid(cred, imgp->ip_origvattr->va_gid, &leave_sugid_clear) || !leave_sugid_clear) ||
6409 (kauth_cred_getgid(cred) != imgp->ip_origvattr->va_gid)))) {
6410 #if CONFIG_MACF
6411 /* label for MAC transition and neither VSUID nor VSGID */
6412 handle_mac_transition:
6413 #endif
6414
6415 #if CONFIG_SETUID
6416 /*
6417 * Replace the credential with a copy of itself if euid or
6418 * egid change.
6419 *
6420 * Note: setuid binaries will automatically opt out of
6421 * group resolver participation as a side effect
6422 * of this operation. This is an intentional
6423 * part of the security model, which requires a
6424 * participating credential be established by
6425 * escalating privilege, setting up all other
6426 * aspects of the credential including whether
6427 * or not to participate in external group
6428 * membership resolution, then dropping their
6429 * effective privilege to that of the desired
6430 * final credential state.
6431 *
6432 * Modifications to p_ucred must be guarded using the
6433 * proc's ucred lock. This prevents others from accessing
6434 * a garbage credential.
6435 */
6436
6437 if (imgp->ip_origvattr->va_mode & VSUID) {
6438 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred) {
6439 return kauth_cred_setresuid(my_cred,
6440 KAUTH_UID_NONE,
6441 imgp->ip_origvattr->va_uid,
6442 imgp->ip_origvattr->va_uid,
6443 KAUTH_UID_NONE);
6444 });
6445 }
6446
6447 if (imgp->ip_origvattr->va_mode & VSGID) {
6448 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred) {
6449 return kauth_cred_setresgid(my_cred,
6450 KAUTH_GID_NONE,
6451 imgp->ip_origvattr->va_gid,
6452 imgp->ip_origvattr->va_gid);
6453 });
6454 }
6455 #endif /* CONFIG_SETUID */
6456
6457 #if CONFIG_MACF
6458 /*
6459 * If a policy has indicated that it will transition the label,
6460 * before making the call into the MAC policies, get a new
6461 * duplicate credential, so they can modify it without
6462 * modifying any others sharing it.
6463 */
6464 if (mac_transition) {
6465 /*
6466 * This hook may generate upcalls that require
6467 * importance donation from the kernel.
6468 * (23925818)
6469 */
6470 thread_t thread = current_thread();
6471 thread_enable_send_importance(thread, TRUE);
6472 kauth_proc_label_update_execve(p,
6473 imgp->ip_vfs_context,
6474 imgp->ip_vp,
6475 imgp->ip_arch_offset,
6476 imgp->ip_scriptvp,
6477 imgp->ip_scriptlabelp,
6478 imgp->ip_execlabelp,
6479 &imgp->ip_csflags,
6480 &imgp->ip_px_smpx,
6481 &disjoint_cred, /* will be non zero if disjoint */
6482 &label_update_return);
6483 thread_enable_send_importance(thread, FALSE);
6484
6485 if (disjoint_cred) {
6486 /*
6487 * If updating the MAC label resulted in a
6488 * disjoint credential, flag that we need to
6489 * set the P_SUGID bit. This protects
6490 * against debuggers being attached by an
6491 * insufficiently privileged process onto the
6492 * result of a transition to a more privileged
6493 * credential.
6494 */
6495 leave_sugid_clear = 0;
6496 }
6497
6498 imgp->ip_mac_return = label_update_return;
6499 }
6500
6501 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);
6502
6503 #endif /* CONFIG_MACF */
6504
6505 /*
6506 * If 'leave_sugid_clear' is non-zero, then we passed the
6507 * VSUID and MACF checks, and successfully determined that
6508 * the previous cred was a member of the VSGID group, but
6509 * that it was not the default at the time of the execve,
6510 * and that the post-labelling credential was not disjoint.
6511 * So we don't set the P_SUGID or reset mach ports and fds
6512 * on the basis of simply running this code.
6513 */
6514 if (mac_reset_ipc || !leave_sugid_clear) {
6515 /*
6516 * Have mach reset the task and thread ports.
6517 * We don't want anyone who had the ports before
6518 * a setuid exec to be able to access/control the
6519 * task/thread after.
6520 */
6521 ipc_task_reset((imgp->ip_new_thread != NULL) ?
6522 get_threadtask(imgp->ip_new_thread) : proc_task(p));
6523 ipc_thread_reset((imgp->ip_new_thread != NULL) ?
6524 imgp->ip_new_thread : current_thread());
6525 }
6526
6527 if (!leave_sugid_clear) {
6528 /*
6529 * Flag the process as setuid.
6530 */
6531 OSBitOrAtomic(P_SUGID, &p->p_flag);
6532
6533 /*
6534 * Radar 2261856; setuid security hole fix
6535 * XXX For setuid processes, attempt to ensure that
6536 * stdin, stdout, and stderr are already allocated.
6537 * We do not want userland to accidentally allocate
6538 * descriptors in this range which has implied meaning
6539 * to libc.
6540 */
6541 for (i = 0; i < 3; i++) {
6542 if (fp_get_noref_locked(p, i) != NULL) {
6543 continue;
6544 }
6545
6546 /*
6547 * Do the kernel equivalent of
6548 *
6549 * if i == 0
6550 * (void) open("/dev/null", O_RDONLY);
6551 * else
6552 * (void) open("/dev/null", O_WRONLY);
6553 */
6554
6555 struct fileproc *fp;
6556 int indx;
6557 int flag;
6558 struct nameidata *ndp = NULL;
6559
6560 if (i == 0) {
6561 flag = FREAD;
6562 } else {
6563 flag = FWRITE;
6564 }
6565
6566 if ((error = falloc(p,
6567 &fp, &indx, imgp->ip_vfs_context)) != 0) {
6568 continue;
6569 }
6570
6571 ndp = kalloc_type(struct nameidata,
6572 Z_WAITOK | Z_ZERO | Z_NOFAIL);
6573
6574 NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW, UIO_SYSSPACE,
6575 CAST_USER_ADDR_T("/dev/null"),
6576 imgp->ip_vfs_context);
6577
6578 if ((error = vn_open(ndp, flag, 0)) != 0) {
6579 fp_free(p, indx, fp);
6580 kfree_type(struct nameidata, ndp);
6581 break;
6582 }
6583
6584 struct fileglob *fg = fp->fp_glob;
6585
6586 fg->fg_flag = flag;
6587 fg->fg_ops = &vnops;
6588 fp_set_data(fp, ndp->ni_vp);
6589
6590 vnode_put(ndp->ni_vp);
6591
6592 proc_fdlock(p);
6593 procfdtbl_releasefd(p, indx, NULL);
6594 fp_drop(p, indx, fp, 1);
6595 proc_fdunlock(p);
6596
6597 kfree_type(struct nameidata, ndp);
6598 }
6599 }
6600 }
6601 #if CONFIG_MACF
6602 else {
6603 /*
6604 * We are here because we were told that the MAC label will
6605 * be transitioned, and the binary is not VSUID or VSGID; to
6606 * deal with this case, we could either duplicate a lot of
6607 * code, or we can indicate we want to default the P_SUGID
6608 * bit clear and jump back up.
6609 */
6610 if (mac_transition) {
6611 leave_sugid_clear = 1;
6612 goto handle_mac_transition;
6613 }
6614 }
6615
6616 #endif /* CONFIG_MACF */
6617
6618 /*
6619 * Implement the semantic where the effective user and group become
6620 * the saved user and group in exec'ed programs.
6621 *
6622 * Modifications to p_ucred must be guarded using the
6623 * proc's ucred lock. This prevents others from accessing
6624 * a garbage credential.
6625 */
6626 proc_update_label(p, false, ^kauth_cred_t (kauth_cred_t my_cred) {
6627 return kauth_cred_setsvuidgid(my_cred,
6628 kauth_cred_getuid(my_cred),
6629 kauth_cred_getgid(my_cred));
6630 });
6631
6632 if (imgp->ip_new_thread != NULL) {
6633 task = get_threadtask(imgp->ip_new_thread);
6634 } else {
6635 task = proc_task(p);
6636 }
6637
6638 /* Update the process' identity version and set the security token */
6639 proc_setpidversion(p, OSIncrementAtomic(&nextpidversion));
6640 task_set_uniqueid(task);
6641 set_security_token_task_internal(p, task);
6642
6643 return error;
6644 }
6645
6646
6647 /*
6648 * create_unix_stack
6649 *
6650 * Description: Set the user stack address for the process to the provided
6651 * address. If a custom stack was not set as a result of the
6652 * load process (i.e. as specified by the image file for the
6653 * executable), then allocate the stack in the provided map and
6654 * set up appropriate guard pages for enforcing administrative
6655 * limits on stack growth, if they end up being needed.
6656 *
6657 * Parameters: p Process to set stack on
6658 * load_result Information from mach-o load commands
6659 * map Address map in which to allocate the new stack
6660 *
6661 * Returns: KERN_SUCCESS Stack successfully created
6662 * !KERN_SUCCESS Mach failure code
6663 */
6664 __attribute__((noinline))
6665 static kern_return_t
create_unix_stack(vm_map_t map,load_result_t * load_result,proc_t p)6666 create_unix_stack(vm_map_t map, load_result_t* load_result,
6667 proc_t p)
6668 {
6669 mach_vm_size_t size, prot_size;
6670 mach_vm_offset_t addr, prot_addr;
6671 kern_return_t kr;
6672
6673 mach_vm_address_t user_stack = load_result->user_stack;
6674
6675 proc_lock(p);
6676 p->user_stack = (uintptr_t)user_stack;
6677 if (load_result->custom_stack) {
6678 p->p_lflag |= P_LCUSTOM_STACK;
6679 }
6680 proc_unlock(p);
6681 if (vm_map_page_shift(map) < (int)PAGE_SHIFT) {
6682 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);
6683 }
6684
6685 if (load_result->user_stack_alloc_size > 0) {
6686 /*
6687 * Allocate enough space for the maximum stack size we
6688 * will ever authorize and an extra page to act as
6689 * a guard page for stack overflows. For default stacks,
6690 * vm_initial_limit_stack takes care of the extra guard page.
6691 * Otherwise we must allocate it ourselves.
6692 */
6693 if (mach_vm_round_page_overflow(load_result->user_stack_alloc_size, &size)) {
6694 return KERN_INVALID_ARGUMENT;
6695 }
6696 addr = vm_map_trunc_page(load_result->user_stack - size,
6697 vm_map_page_mask(map));
6698 kr = mach_vm_allocate_kernel(map, &addr, size,
6699 VM_FLAGS_FIXED, VM_MEMORY_STACK);
6700 if (kr != KERN_SUCCESS) {
6701 // Can't allocate at default location, try anywhere
6702 addr = 0;
6703 kr = mach_vm_allocate_kernel(map, &addr, size,
6704 VM_FLAGS_ANYWHERE, VM_MEMORY_STACK);
6705 if (kr != KERN_SUCCESS) {
6706 return kr;
6707 }
6708
6709 user_stack = addr + size;
6710 load_result->user_stack = (user_addr_t)user_stack;
6711
6712 proc_lock(p);
6713 p->user_stack = (uintptr_t)user_stack;
6714 proc_unlock(p);
6715 }
6716
6717 load_result->user_stack_alloc = (user_addr_t)addr;
6718
6719 /*
6720 * And prevent access to what's above the current stack
6721 * size limit for this process.
6722 */
6723 if (load_result->user_stack_size == 0) {
6724 load_result->user_stack_size = proc_limitgetcur(p, RLIMIT_STACK);
6725 prot_size = vm_map_trunc_page(size - load_result->user_stack_size, vm_map_page_mask(map));
6726 } else {
6727 prot_size = PAGE_SIZE;
6728 }
6729
6730 prot_addr = addr;
6731 kr = mach_vm_protect(map,
6732 prot_addr,
6733 prot_size,
6734 FALSE,
6735 VM_PROT_NONE);
6736 if (kr != KERN_SUCCESS) {
6737 (void)mach_vm_deallocate(map, addr, size);
6738 return kr;
6739 }
6740 }
6741
6742 return KERN_SUCCESS;
6743 }
6744
6745 #include <sys/reboot.h>
6746
6747 /*
6748 * load_init_program_at_path
6749 *
6750 * Description: Load the "init" program; in most cases, this will be "launchd"
6751 *
6752 * Parameters: p Process to call execve() to create
6753 * the "init" program
6754 * scratch_addr Page in p, scratch space
6755 * path NULL terminated path
6756 *
6757 * Returns: KERN_SUCCESS Success
6758 * !KERN_SUCCESS See execve/mac_execve for error codes
6759 *
6760 * Notes: The process that is passed in is the first manufactured
6761 * process on the system, and gets here via bsd_ast() firing
6762 * for the first time. This is done to ensure that bsd_init()
6763 * has run to completion.
6764 *
6765 * The address map of the first manufactured process matches the
6766 * word width of the kernel. Once the self-exec completes, the
6767 * initproc might be different.
6768 */
6769 static int
load_init_program_at_path(proc_t p,user_addr_t scratch_addr,const char * path)6770 load_init_program_at_path(proc_t p, user_addr_t scratch_addr, const char* path)
6771 {
6772 int retval[2];
6773 int error;
6774 struct execve_args init_exec_args;
6775 user_addr_t argv0 = USER_ADDR_NULL, argv1 = USER_ADDR_NULL;
6776
6777 /*
6778 * Validate inputs and pre-conditions
6779 */
6780 assert(p);
6781 assert(scratch_addr);
6782 assert(path);
6783
6784 /*
6785 * Copy out program name.
6786 */
6787 size_t path_length = strlen(path) + 1;
6788 argv0 = scratch_addr;
6789 error = copyout(path, argv0, path_length);
6790 if (error) {
6791 return error;
6792 }
6793
6794 scratch_addr = USER_ADDR_ALIGN(scratch_addr + path_length, sizeof(user_addr_t));
6795
6796 /*
6797 * Put out first (and only) argument, similarly.
6798 * Assumes everything fits in a page as allocated above.
6799 */
6800 if (boothowto & RB_SINGLE) {
6801 const char *init_args = "-s";
6802 size_t init_args_length = strlen(init_args) + 1;
6803
6804 argv1 = scratch_addr;
6805 error = copyout(init_args, argv1, init_args_length);
6806 if (error) {
6807 return error;
6808 }
6809
6810 scratch_addr = USER_ADDR_ALIGN(scratch_addr + init_args_length, sizeof(user_addr_t));
6811 }
6812
6813 if (proc_is64bit(p)) {
6814 user64_addr_t argv64bit[3] = {};
6815
6816 argv64bit[0] = argv0;
6817 argv64bit[1] = argv1;
6818 argv64bit[2] = USER_ADDR_NULL;
6819
6820 error = copyout(argv64bit, scratch_addr, sizeof(argv64bit));
6821 if (error) {
6822 return error;
6823 }
6824 } else {
6825 user32_addr_t argv32bit[3] = {};
6826
6827 argv32bit[0] = (user32_addr_t)argv0;
6828 argv32bit[1] = (user32_addr_t)argv1;
6829 argv32bit[2] = USER_ADDR_NULL;
6830
6831 error = copyout(argv32bit, scratch_addr, sizeof(argv32bit));
6832 if (error) {
6833 return error;
6834 }
6835 }
6836
6837 /*
6838 * Set up argument block for fake call to execve.
6839 */
6840 init_exec_args.fname = argv0;
6841 init_exec_args.argp = scratch_addr;
6842 init_exec_args.envp = USER_ADDR_NULL;
6843
6844 /*
6845 * So that init task is set with uid,gid 0 token
6846 */
6847 set_security_token(p);
6848
6849 return execve(p, &init_exec_args, retval);
6850 }
6851
6852 static const char * init_programs[] = {
6853 #if DEBUG
6854 "/usr/appleinternal/sbin/launchd.debug",
6855 #endif
6856 #if DEVELOPMENT || DEBUG
6857 "/usr/appleinternal/sbin/launchd.development",
6858 #endif
6859 "/sbin/launchd",
6860 };
6861
6862 /*
6863 * load_init_program
6864 *
6865 * Description: Load the "init" program; in most cases, this will be "launchd"
6866 *
6867 * Parameters: p Process to call execve() to create
6868 * the "init" program
6869 *
6870 * Returns: (void)
6871 *
6872 * Notes: The process that is passed in is the first manufactured
6873 * process on the system, and gets here via bsd_ast() firing
6874 * for the first time. This is done to ensure that bsd_init()
6875 * has run to completion.
6876 *
6877 * In DEBUG & DEVELOPMENT builds, the launchdsuffix boot-arg
6878 * may be used to select a specific launchd executable. As with
6879 * the kcsuffix boot-arg, setting launchdsuffix to "" or "release"
6880 * will force /sbin/launchd to be selected.
6881 *
6882 * Search order by build:
6883 *
6884 * DEBUG DEVELOPMENT RELEASE PATH
6885 * ----------------------------------------------------------------------------------
6886 * 1 1 NA /usr/appleinternal/sbin/launchd.$LAUNCHDSUFFIX
6887 * 2 NA NA /usr/appleinternal/sbin/launchd.debug
6888 * 3 2 NA /usr/appleinternal/sbin/launchd.development
6889 * 4 3 1 /sbin/launchd
6890 */
6891 void
load_init_program(proc_t p)6892 load_init_program(proc_t p)
6893 {
6894 uint32_t i;
6895 int error;
6896 vm_map_t map = current_map();
6897 mach_vm_offset_t scratch_addr = 0;
6898 mach_vm_size_t map_page_size = vm_map_page_size(map);
6899
6900 (void) mach_vm_allocate_kernel(map, &scratch_addr, map_page_size, VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_NONE);
6901 #if CONFIG_MEMORYSTATUS
6902 (void) memorystatus_init_at_boot_snapshot();
6903 #endif /* CONFIG_MEMORYSTATUS */
6904
6905 #if DEBUG || DEVELOPMENT
6906 /* Check for boot-arg suffix first */
6907 char launchd_suffix[64];
6908 if (PE_parse_boot_argn("launchdsuffix", launchd_suffix, sizeof(launchd_suffix))) {
6909 char launchd_path[128];
6910 boolean_t is_release_suffix = ((launchd_suffix[0] == 0) ||
6911 (strcmp(launchd_suffix, "release") == 0));
6912
6913 if (is_release_suffix) {
6914 printf("load_init_program: attempting to load /sbin/launchd\n");
6915 error = load_init_program_at_path(p, (user_addr_t)scratch_addr, "/sbin/launchd");
6916 if (!error) {
6917 return;
6918 }
6919
6920 panic("Process 1 exec of launchd.release failed, errno %d", error);
6921 } else {
6922 strlcpy(launchd_path, "/usr/appleinternal/sbin/launchd.", sizeof(launchd_path));
6923 strlcat(launchd_path, launchd_suffix, sizeof(launchd_path));
6924
6925 printf("load_init_program: attempting to load %s\n", launchd_path);
6926 error = load_init_program_at_path(p, (user_addr_t)scratch_addr, launchd_path);
6927 if (!error) {
6928 return;
6929 } else if (error != ENOENT) {
6930 printf("load_init_program: failed loading %s: errno %d\n", launchd_path, error);
6931 }
6932 }
6933 }
6934 #endif
6935
6936 error = ENOENT;
6937 for (i = 0; i < sizeof(init_programs) / sizeof(init_programs[0]); i++) {
6938 printf("load_init_program: attempting to load %s\n", init_programs[i]);
6939 error = load_init_program_at_path(p, (user_addr_t)scratch_addr, init_programs[i]);
6940 if (!error) {
6941 return;
6942 } else if (error != ENOENT) {
6943 printf("load_init_program: failed loading %s: errno %d\n", init_programs[i], error);
6944 }
6945 }
6946
6947 panic("Process 1 exec of %s failed, errno %d", ((i == 0) ? "<null>" : init_programs[i - 1]), error);
6948 }
6949
6950 /*
6951 * load_return_to_errno
6952 *
6953 * Description: Convert a load_return_t (Mach error) to an errno (BSD error)
6954 *
6955 * Parameters: lrtn Mach error number
6956 *
6957 * Returns: (int) BSD error number
6958 * 0 Success
6959 * EBADARCH Bad architecture
6960 * EBADMACHO Bad Mach object file
6961 * ESHLIBVERS Bad shared library version
6962 * ENOMEM Out of memory/resource shortage
6963 * EACCES Access denied
6964 * ENOENT Entry not found (usually "file does
6965 * does not exist")
6966 * EIO An I/O error occurred
6967 * EBADEXEC The executable is corrupt/unknown
6968 */
6969 static int
load_return_to_errno(load_return_t lrtn)6970 load_return_to_errno(load_return_t lrtn)
6971 {
6972 switch (lrtn) {
6973 case LOAD_SUCCESS:
6974 return 0;
6975 case LOAD_BADARCH:
6976 return EBADARCH;
6977 case LOAD_BADMACHO:
6978 case LOAD_BADMACHO_UPX:
6979 return EBADMACHO;
6980 case LOAD_SHLIB:
6981 return ESHLIBVERS;
6982 case LOAD_NOSPACE:
6983 case LOAD_RESOURCE:
6984 return ENOMEM;
6985 case LOAD_PROTECT:
6986 return EACCES;
6987 case LOAD_ENOENT:
6988 return ENOENT;
6989 case LOAD_IOERROR:
6990 return EIO;
6991 case LOAD_DECRYPTFAIL:
6992 return EAUTH;
6993 case LOAD_FAILURE:
6994 default:
6995 return EBADEXEC;
6996 }
6997 }
6998
6999 #include <mach/mach_types.h>
7000 #include <mach/vm_prot.h>
7001 #include <mach/semaphore.h>
7002 #include <mach/sync_policy.h>
7003 #include <kern/clock.h>
7004 #include <mach/kern_return.h>
7005
7006 /*
7007 * execargs_alloc
7008 *
7009 * Description: Allocate the block of memory used by the execve arguments.
7010 * At the same time, we allocate a page so that we can read in
7011 * the first page of the image.
7012 *
7013 * Parameters: struct image_params * the image parameter block
7014 *
7015 * Returns: 0 Success
7016 * EINVAL Invalid argument
7017 * EACCES Permission denied
7018 * EINTR Interrupted function
7019 * ENOMEM Not enough space
7020 *
7021 * Notes: This is a temporary allocation into the kernel address space
7022 * to enable us to copy arguments in from user space. This is
7023 * necessitated by not mapping the process calling execve() into
7024 * the kernel address space during the execve() system call.
7025 *
7026 * We assemble the argument and environment, etc., into this
7027 * region before copying it as a single block into the child
7028 * process address space (at the top or bottom of the stack,
7029 * depending on which way the stack grows; see the function
7030 * exec_copyout_strings() for details).
7031 *
7032 * This ends up with a second (possibly unnecessary) copy compared
7033 * with assembing the data directly into the child address space,
7034 * instead, but since we cannot be guaranteed that the parent has
7035 * not modified its environment, we can't really know that it's
7036 * really a block there as well.
7037 */
7038
7039
7040 static int execargs_waiters = 0;
7041 static LCK_MTX_DECLARE_ATTR(execargs_cache_lock, &proc_lck_grp, &proc_lck_attr);
7042
7043 static void
execargs_lock_lock(void)7044 execargs_lock_lock(void)
7045 {
7046 lck_mtx_lock_spin(&execargs_cache_lock);
7047 }
7048
7049 static void
execargs_lock_unlock(void)7050 execargs_lock_unlock(void)
7051 {
7052 lck_mtx_unlock(&execargs_cache_lock);
7053 }
7054
7055 static wait_result_t
execargs_lock_sleep(void)7056 execargs_lock_sleep(void)
7057 {
7058 return lck_mtx_sleep(&execargs_cache_lock, LCK_SLEEP_DEFAULT, &execargs_free_count, THREAD_INTERRUPTIBLE);
7059 }
7060
7061 static kern_return_t
execargs_purgeable_allocate(char ** execarg_address)7062 execargs_purgeable_allocate(char **execarg_address)
7063 {
7064 mach_vm_offset_t addr = 0;
7065 kern_return_t kr = mach_vm_allocate_kernel(bsd_pageable_map, &addr,
7066 BSD_PAGEABLE_SIZE_PER_EXEC, VM_FLAGS_ANYWHERE | VM_FLAGS_PURGABLE,
7067 VM_KERN_MEMORY_NONE);
7068 *execarg_address = (char *)addr;
7069 assert(kr == KERN_SUCCESS);
7070 return kr;
7071 }
7072
7073 static kern_return_t
execargs_purgeable_reference(void * execarg_address)7074 execargs_purgeable_reference(void *execarg_address)
7075 {
7076 int state = VM_PURGABLE_NONVOLATILE;
7077 kern_return_t kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
7078
7079 assert(kr == KERN_SUCCESS);
7080 return kr;
7081 }
7082
7083 static kern_return_t
execargs_purgeable_volatilize(void * execarg_address)7084 execargs_purgeable_volatilize(void *execarg_address)
7085 {
7086 int state = VM_PURGABLE_VOLATILE | VM_PURGABLE_ORDERING_OBSOLETE;
7087 kern_return_t kr;
7088 kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
7089
7090 assert(kr == KERN_SUCCESS);
7091
7092 return kr;
7093 }
7094
7095 static void
execargs_wakeup_waiters(void)7096 execargs_wakeup_waiters(void)
7097 {
7098 thread_wakeup(&execargs_free_count);
7099 }
7100
7101 static int
execargs_alloc(struct image_params * imgp)7102 execargs_alloc(struct image_params *imgp)
7103 {
7104 kern_return_t kret;
7105 wait_result_t res;
7106 int i, cache_index = -1;
7107
7108 execargs_lock_lock();
7109
7110 while (execargs_free_count == 0) {
7111 execargs_waiters++;
7112 res = execargs_lock_sleep();
7113 execargs_waiters--;
7114 if (res != THREAD_AWAKENED) {
7115 execargs_lock_unlock();
7116 return EINTR;
7117 }
7118 }
7119
7120 execargs_free_count--;
7121
7122 for (i = 0; i < execargs_cache_size; i++) {
7123 vm_offset_t element = execargs_cache[i];
7124 if (element) {
7125 cache_index = i;
7126 imgp->ip_strings = (char *)(execargs_cache[i]);
7127 execargs_cache[i] = 0;
7128 break;
7129 }
7130 }
7131
7132 assert(execargs_free_count >= 0);
7133
7134 execargs_lock_unlock();
7135
7136 if (cache_index == -1) {
7137 kret = execargs_purgeable_allocate(&imgp->ip_strings);
7138 } else {
7139 kret = execargs_purgeable_reference(imgp->ip_strings);
7140 }
7141
7142 assert(kret == KERN_SUCCESS);
7143 if (kret != KERN_SUCCESS) {
7144 return ENOMEM;
7145 }
7146
7147 /* last page used to read in file headers */
7148 imgp->ip_vdata = imgp->ip_strings + (NCARGS + PAGE_SIZE);
7149 imgp->ip_strendp = imgp->ip_strings;
7150 imgp->ip_argspace = NCARGS;
7151 imgp->ip_strspace = (NCARGS + PAGE_SIZE);
7152
7153 return 0;
7154 }
7155
7156 /*
7157 * execargs_free
7158 *
7159 * Description: Free the block of memory used by the execve arguments and the
7160 * first page of the executable by a previous call to the function
7161 * execargs_alloc().
7162 *
7163 * Parameters: struct image_params * the image parameter block
7164 *
7165 * Returns: 0 Success
7166 * EINVAL Invalid argument
7167 * EINTR Oeration interrupted
7168 */
7169 static int
execargs_free(struct image_params * imgp)7170 execargs_free(struct image_params *imgp)
7171 {
7172 kern_return_t kret;
7173 int i;
7174 boolean_t needs_wakeup = FALSE;
7175
7176 kret = execargs_purgeable_volatilize(imgp->ip_strings);
7177
7178 execargs_lock_lock();
7179 execargs_free_count++;
7180
7181 for (i = 0; i < execargs_cache_size; i++) {
7182 vm_offset_t element = execargs_cache[i];
7183 if (element == 0) {
7184 execargs_cache[i] = (vm_offset_t) imgp->ip_strings;
7185 imgp->ip_strings = NULL;
7186 break;
7187 }
7188 }
7189
7190 assert(imgp->ip_strings == NULL);
7191
7192 if (execargs_waiters > 0) {
7193 needs_wakeup = TRUE;
7194 }
7195
7196 execargs_lock_unlock();
7197
7198 if (needs_wakeup == TRUE) {
7199 execargs_wakeup_waiters();
7200 }
7201
7202 return kret == KERN_SUCCESS ? 0 : EINVAL;
7203 }
7204
7205 void
uthread_set_exec_data(struct uthread * uth,struct image_params * imgp)7206 uthread_set_exec_data(struct uthread *uth, struct image_params *imgp)
7207 {
7208 uth->uu_save.uus_exec_data.imgp = imgp;
7209 }
7210
7211 size_t
thread_get_current_exec_path(char * path,size_t size)7212 thread_get_current_exec_path(char *path, size_t size)
7213 {
7214 struct uthread *uth = current_uthread();
7215 struct image_params *imgp = uth->uu_save.uus_exec_data.imgp;
7216 size_t string_size = 0;
7217 char *exec_path;
7218
7219 if (path == NULL || imgp == NULL || imgp->ip_strings == NULL) {
7220 return 0;
7221 }
7222
7223 exec_path = imgp->ip_strings + strlen(EXECUTABLE_KEY);
7224 string_size = imgp->ip_strendp - exec_path;
7225 string_size = MIN(MAXPATHLEN, string_size);
7226 string_size = MIN(size, string_size);
7227
7228 string_size = strlcpy(path, exec_path, string_size);
7229 return string_size;
7230 }
7231 static void
exec_resettextvp(proc_t p,struct image_params * imgp)7232 exec_resettextvp(proc_t p, struct image_params *imgp)
7233 {
7234 vnode_t vp;
7235 off_t offset;
7236 vnode_t tvp = p->p_textvp;
7237 int ret;
7238
7239 vp = imgp->ip_vp;
7240 offset = imgp->ip_arch_offset;
7241
7242 if (vp == NULLVP) {
7243 panic("exec_resettextvp: expected valid vp");
7244 }
7245
7246 ret = vnode_ref(vp);
7247 proc_lock(p);
7248 if (ret == 0) {
7249 p->p_textvp = vp;
7250 p->p_textoff = offset;
7251 } else {
7252 p->p_textvp = NULLVP; /* this is paranoia */
7253 p->p_textoff = 0;
7254 }
7255 proc_unlock(p);
7256
7257 if (tvp != NULLVP) {
7258 if (vnode_getwithref(tvp) == 0) {
7259 vnode_rele(tvp);
7260 vnode_put(tvp);
7261 }
7262 }
7263 }
7264
7265 // Includes the 0-byte (therefore "SIZE" instead of "LEN").
7266 static const size_t CS_CDHASH_STRING_SIZE = CS_CDHASH_LEN * 2 + 1;
7267
7268 static void
cdhash_to_string(char str[CS_CDHASH_STRING_SIZE],uint8_t const * const cdhash)7269 cdhash_to_string(char str[CS_CDHASH_STRING_SIZE], uint8_t const * const cdhash)
7270 {
7271 static char const nibble[] = "0123456789abcdef";
7272
7273 /* Apparently still the safest way to get a hex representation
7274 * of binary data.
7275 * xnu's printf routines have %*D/%20D in theory, but "not really", see:
7276 * <rdar://problem/33328859> confusion around %*D/%nD in printf
7277 */
7278 for (int i = 0; i < CS_CDHASH_LEN; ++i) {
7279 str[i * 2] = nibble[(cdhash[i] & 0xf0) >> 4];
7280 str[i * 2 + 1] = nibble[cdhash[i] & 0x0f];
7281 }
7282 str[CS_CDHASH_STRING_SIZE - 1] = 0;
7283 }
7284
7285 /*
7286 * __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__
7287 *
7288 * Description: Waits for the userspace daemon to respond to the request
7289 * we made. Function declared non inline to be visible in
7290 * stackshots and spindumps as well as debugging.
7291 */
7292 __attribute__((noinline)) int
__EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port,int32_t new_pid)7293 __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid)
7294 {
7295 return find_code_signature(task_access_port, new_pid);
7296 }
7297
7298 /*
7299 * Update signature dependent process state, called by
7300 * process_signature.
7301 */
7302 static int
proc_process_signature(proc_t p,os_reason_t * signature_failure_reason)7303 proc_process_signature(proc_t p, os_reason_t *signature_failure_reason)
7304 {
7305 int error = 0;
7306 char const *error_msg = NULL;
7307
7308 kern_return_t kr = machine_task_process_signature(proc_get_task_raw(p), proc_platform(p), proc_sdk(p), &error_msg);
7309
7310 if (kr != KERN_SUCCESS) {
7311 error = EINVAL;
7312
7313 if (error_msg != NULL) {
7314 uint32_t error_msg_len = (uint32_t)strlen(error_msg) + 1;
7315 mach_vm_address_t data_addr = 0;
7316 int reason_error = 0;
7317 int kcdata_error = 0;
7318
7319 os_reason_t reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
7320 reason->osr_flags = OS_REASON_FLAG_GENERATE_CRASH_REPORT | OS_REASON_FLAG_CONSISTENT_FAILURE;
7321
7322 if ((reason_error = os_reason_alloc_buffer_noblock(reason,
7323 kcdata_estimate_required_buffer_size(1, error_msg_len))) == 0 &&
7324 (kcdata_error = kcdata_get_memory_addr(&reason->osr_kcd_descriptor,
7325 EXIT_REASON_USER_DESC, error_msg_len,
7326 &data_addr)) == KERN_SUCCESS) {
7327 kern_return_t mc_error = kcdata_memcpy(&reason->osr_kcd_descriptor, (mach_vm_address_t)data_addr,
7328 error_msg, error_msg_len);
7329
7330 if (mc_error != KERN_SUCCESS) {
7331 printf("process_signature: failed to copy reason string (kcdata_memcpy error: %d)\n",
7332 mc_error);
7333 }
7334 } else {
7335 printf("failed to allocate space for reason string (os_reason_alloc_buffer error: %d, kcdata error: %d, length: %u)\n",
7336 reason_error, kcdata_error, error_msg_len);
7337 }
7338
7339 assert(*signature_failure_reason == NULL); // shouldn't have gotten so far
7340 *signature_failure_reason = reason;
7341 }
7342 }
7343 return error;
7344 }
7345
7346 static int
process_signature(proc_t p,struct image_params * imgp)7347 process_signature(proc_t p, struct image_params *imgp)
7348 {
7349 mach_port_t port = IPC_PORT_NULL;
7350 kern_return_t kr = KERN_FAILURE;
7351 int error = EACCES;
7352 boolean_t unexpected_failure = FALSE;
7353 struct cs_blob *csb;
7354 boolean_t require_success = FALSE;
7355 int spawn = (imgp->ip_flags & IMGPF_SPAWN);
7356 const int vfexec = 0;
7357 os_reason_t signature_failure_reason = OS_REASON_NULL;
7358
7359 /*
7360 * Override inherited code signing flags with the
7361 * ones for the process that is being successfully
7362 * loaded
7363 */
7364 proc_lock(p);
7365 proc_csflags_update(p, imgp->ip_csflags);
7366 proc_unlock(p);
7367
7368 /* Set the switch_protect flag on the map */
7369 if (proc_getcsflags(p) & (CS_HARD | CS_KILL)) {
7370 vm_map_switch_protect(get_task_map(proc_task(p)), TRUE);
7371 }
7372 /* set the cs_enforced flags in the map */
7373 if (proc_getcsflags(p) & CS_ENFORCEMENT) {
7374 vm_map_cs_enforcement_set(get_task_map(proc_task(p)), TRUE);
7375 } else {
7376 vm_map_cs_enforcement_set(get_task_map(proc_task(p)), FALSE);
7377 }
7378
7379 /*
7380 * image activation may be failed due to policy
7381 * which is unexpected but security framework does not
7382 * approve of exec, kill and return immediately.
7383 */
7384 if (imgp->ip_mac_return != 0) {
7385 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7386 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY, 0, 0);
7387 signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY);
7388 error = imgp->ip_mac_return;
7389 unexpected_failure = TRUE;
7390 goto done;
7391 }
7392
7393 if (imgp->ip_cs_error != OS_REASON_NULL) {
7394 signature_failure_reason = imgp->ip_cs_error;
7395 imgp->ip_cs_error = OS_REASON_NULL;
7396 error = EACCES;
7397 goto done;
7398 }
7399
7400 /* call the launch constraints hook */
7401 os_reason_t launch_constraint_reason;
7402 if ((error = mac_proc_check_launch_constraints(p, imgp, &launch_constraint_reason)) != 0) {
7403 signature_failure_reason = launch_constraint_reason;
7404 goto done;
7405 }
7406
7407 #if XNU_TARGET_OS_OSX
7408 /* Check for platform passed in spawn attr if iOS binary is being spawned */
7409 if (proc_platform(p) == PLATFORM_IOS) {
7410 struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
7411 if (psa == NULL || psa->psa_platform == 0) {
7412 boolean_t no_sandbox_entitled = FALSE;
7413 #if DEBUG || DEVELOPMENT
7414 /*
7415 * Allow iOS binaries to spawn on internal systems
7416 * if no-sandbox entitlement is present of unentitled_ios_sim_launch
7417 * boot-arg set to true
7418 */
7419 if (unentitled_ios_sim_launch) {
7420 no_sandbox_entitled = TRUE;
7421 } else {
7422 no_sandbox_entitled = IOVnodeHasEntitlement(imgp->ip_vp,
7423 (int64_t)imgp->ip_arch_offset, "com.apple.private.security.no-sandbox");
7424 }
7425 #endif /* DEBUG || DEVELOPMENT */
7426 if (!no_sandbox_entitled) {
7427 signature_failure_reason = os_reason_create(OS_REASON_EXEC,
7428 EXEC_EXIT_REASON_WRONG_PLATFORM);
7429 error = EACCES;
7430 goto done;
7431 }
7432 printf("Allowing spawn of iOS binary %s since it has "
7433 "com.apple.private.security.no-sandbox entitlement or unentitled_ios_sim_launch "
7434 "boot-arg set to true\n", p->p_name);
7435 } else if (psa->psa_platform != PLATFORM_IOS) {
7436 /* Simulator binary spawned with wrong platform */
7437 signature_failure_reason = os_reason_create(OS_REASON_EXEC,
7438 EXEC_EXIT_REASON_WRONG_PLATFORM);
7439 error = EACCES;
7440 goto done;
7441 } else {
7442 printf("Allowing spawn of iOS binary %s since correct platform was passed in spawn\n",
7443 p->p_name);
7444 }
7445 }
7446 #endif /* XNU_TARGET_OS_OSX */
7447
7448 /* If the code signature came through the image activation path, we skip the
7449 * taskgated / externally attached path. */
7450 if (imgp->ip_csflags & CS_SIGNED) {
7451 error = 0;
7452 goto done;
7453 }
7454
7455 /* The rest of the code is for signatures that either already have been externally
7456 * attached (likely, but not necessarily by a previous run through the taskgated
7457 * path), or that will now be attached by taskgated. */
7458
7459 kr = task_get_task_access_port(proc_task(p), &port);
7460 if (KERN_SUCCESS != kr || !IPC_PORT_VALID(port)) {
7461 error = 0;
7462 if (require_success) {
7463 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7464 proc_getpid(p), OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT, 0, 0);
7465 signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT);
7466 error = EACCES;
7467 }
7468 goto done;
7469 }
7470
7471 /*
7472 * taskgated returns KERN_SUCCESS if it has completed its work
7473 * and the exec should continue, KERN_FAILURE if the exec should
7474 * fail, or it may error out with different error code in an
7475 * event of mig failure (e.g. process was signalled during the
7476 * rpc call, taskgated died, mig server died etc.).
7477 */
7478
7479 kr = __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(port, proc_getpid(p));
7480 switch (kr) {
7481 case KERN_SUCCESS:
7482 error = 0;
7483 break;
7484 case KERN_FAILURE:
7485 error = EACCES;
7486
7487 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7488 proc_getpid(p), OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG, 0, 0);
7489 signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG);
7490 goto done;
7491 default:
7492 error = EACCES;
7493
7494 KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
7495 proc_getpid(p), OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER, 0, 0);
7496 signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER);
7497 unexpected_failure = TRUE;
7498 goto done;
7499 }
7500
7501 /* Only do this if exec_resettextvp() did not fail */
7502 if (p->p_textvp != NULLVP) {
7503 csb = ubc_cs_blob_get(p->p_textvp, -1, -1, p->p_textoff);
7504
7505 if (csb != NULL) {
7506 /* As the enforcement we can do here is very limited, we only allow things that
7507 * are the only reason why this code path still exists:
7508 * Adhoc signed non-platform binaries without special cs_flags and without any
7509 * entitlements (unrestricted ones still pass AMFI). */
7510 if (
7511 /* Revalidate the blob if necessary through bumped generation count. */
7512 (ubc_cs_generation_check(p->p_textvp) == 0 ||
7513 ubc_cs_blob_revalidate(p->p_textvp, csb, imgp, 0, proc_platform(p)) == 0) &&
7514 /* Only CS_ADHOC, no CS_KILL, CS_HARD etc. */
7515 (csb->csb_flags & CS_ALLOWED_MACHO) == CS_ADHOC &&
7516 /* If it has a CMS blob, it's not adhoc. The CS_ADHOC flag can lie. */
7517 csblob_find_blob_bytes((const uint8_t *)csb->csb_mem_kaddr, csb->csb_mem_size,
7518 CSSLOT_SIGNATURESLOT,
7519 CSMAGIC_BLOBWRAPPER) == NULL &&
7520 /* It could still be in a trust cache (unlikely with CS_ADHOC), or a magic path. */
7521 csb->csb_platform_binary == 0 &&
7522 /* No entitlements, not even unrestricted ones. */
7523 csb->csb_entitlements_blob == NULL &&
7524 csb->csb_der_entitlements_blob == NULL) {
7525 proc_lock(p);
7526 proc_csflags_set(p, CS_SIGNED | CS_VALID);
7527 proc_unlock(p);
7528 } else {
7529 uint8_t cdhash[CS_CDHASH_LEN];
7530 char cdhash_string[CS_CDHASH_STRING_SIZE];
7531 proc_getcdhash(p, cdhash);
7532 cdhash_to_string(cdhash_string, cdhash);
7533 printf("ignoring detached code signature on '%s' with cdhash '%s' "
7534 "because it is invalid, or not a simple adhoc signature.\n",
7535 p->p_name, cdhash_string);
7536 }
7537 }
7538 }
7539
7540 done:
7541 if (0 == error) {
7542 /*
7543 * Update the new process's signature-dependent process state.
7544 * state.
7545 */
7546
7547 error = proc_process_signature(p, &signature_failure_reason);
7548 }
7549
7550 if (0 == error) {
7551 /*
7552 * Update the new main thread's signature-dependent thread
7553 * state. This was also called when the thread was created,
7554 * but for the main thread the signature was not yet attached
7555 * at that time.
7556 */
7557 kr = thread_process_signature(imgp->ip_new_thread, proc_get_task_raw(p));
7558
7559 if (kr != KERN_SUCCESS) {
7560 error = EINVAL;
7561 signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_MACHINE_THREAD);
7562 }
7563 }
7564
7565 if (0 == error) {
7566 /* The process's code signature related properties are
7567 * fully set up, so this is an opportune moment to log
7568 * platform binary execution, if desired. */
7569 if (platform_exec_logging != 0 && csproc_get_platform_binary(p)) {
7570 uint8_t cdhash[CS_CDHASH_LEN];
7571 char cdhash_string[CS_CDHASH_STRING_SIZE];
7572 proc_getcdhash(p, cdhash);
7573 cdhash_to_string(cdhash_string, cdhash);
7574
7575 os_log(peLog, "CS Platform Exec Logging: Executing platform signed binary "
7576 "'%s' with cdhash %s\n", p->p_name, cdhash_string);
7577 }
7578 } else {
7579 if (!unexpected_failure) {
7580 proc_csflags_set(p, CS_KILLED);
7581 }
7582 /* make very sure execution fails */
7583 if (vfexec || spawn) {
7584 assert(signature_failure_reason != OS_REASON_NULL);
7585 psignal_vfork_with_reason(p, proc_task(p), imgp->ip_new_thread,
7586 SIGKILL, signature_failure_reason);
7587 signature_failure_reason = OS_REASON_NULL;
7588 error = 0;
7589 } else {
7590 assert(signature_failure_reason != OS_REASON_NULL);
7591 psignal_with_reason(p, SIGKILL, signature_failure_reason);
7592 signature_failure_reason = OS_REASON_NULL;
7593 }
7594 }
7595
7596 if (port != IPC_PORT_NULL) {
7597 ipc_port_release_send(port);
7598 }
7599
7600 /* If we hit this, we likely would have leaked an exit reason */
7601 assert(signature_failure_reason == OS_REASON_NULL);
7602 return error;
7603 }
7604
7605 /*
7606 * Typically as soon as we start executing this process, the
7607 * first instruction will trigger a VM fault to bring the text
7608 * pages (as executable) into the address space, followed soon
7609 * thereafter by dyld data structures (for dynamic executable).
7610 * To optimize this, as well as improve support for hardware
7611 * debuggers that can only access resident pages present
7612 * in the process' page tables, we prefault some pages if
7613 * possible. Errors are non-fatal.
7614 */
7615 #ifndef PREVENT_CALLER_STACK_USE
7616 #define PREVENT_CALLER_STACK_USE __attribute__((noinline))
7617 #endif
7618 static void PREVENT_CALLER_STACK_USE
exec_prefault_data(proc_t p __unused,struct image_params * imgp,load_result_t * load_result)7619 exec_prefault_data(proc_t p __unused, struct image_params *imgp, load_result_t *load_result)
7620 {
7621 int ret;
7622 size_t expected_all_image_infos_size;
7623 kern_return_t kr;
7624
7625 /*
7626 * Prefault executable or dyld entry point.
7627 */
7628 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7629 DEBUG4K_LOAD("entry_point 0x%llx\n", (uint64_t)load_result->entry_point);
7630 }
7631 kr = vm_fault(current_map(),
7632 vm_map_trunc_page(load_result->entry_point,
7633 vm_map_page_mask(current_map())),
7634 VM_PROT_READ | VM_PROT_EXECUTE,
7635 FALSE, VM_KERN_MEMORY_NONE,
7636 THREAD_UNINT, NULL, 0);
7637 if (kr != KERN_SUCCESS) {
7638 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);
7639 }
7640
7641 if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
7642 expected_all_image_infos_size = sizeof(struct user64_dyld_all_image_infos);
7643 } else {
7644 expected_all_image_infos_size = sizeof(struct user32_dyld_all_image_infos);
7645 }
7646
7647 /* Decode dyld anchor structure from <mach-o/dyld_images.h> */
7648 if (load_result->dynlinker &&
7649 load_result->all_image_info_addr &&
7650 load_result->all_image_info_size >= expected_all_image_infos_size) {
7651 union {
7652 struct user64_dyld_all_image_infos infos64;
7653 struct user32_dyld_all_image_infos infos32;
7654 } all_image_infos;
7655
7656 /*
7657 * Pre-fault to avoid copyin() going through the trap handler
7658 * and recovery path.
7659 */
7660 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7661 DEBUG4K_LOAD("all_image_info_addr 0x%llx\n", load_result->all_image_info_addr);
7662 }
7663 kr = vm_fault(current_map(),
7664 vm_map_trunc_page(load_result->all_image_info_addr,
7665 vm_map_page_mask(current_map())),
7666 VM_PROT_READ | VM_PROT_WRITE,
7667 FALSE, VM_KERN_MEMORY_NONE,
7668 THREAD_UNINT, NULL, 0);
7669 if (kr != KERN_SUCCESS) {
7670 // 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);
7671 }
7672 if ((load_result->all_image_info_addr & PAGE_MASK) + expected_all_image_infos_size > PAGE_SIZE) {
7673 /* all_image_infos straddles a page */
7674 kr = vm_fault(current_map(),
7675 vm_map_trunc_page(load_result->all_image_info_addr + expected_all_image_infos_size - 1,
7676 vm_map_page_mask(current_map())),
7677 VM_PROT_READ | VM_PROT_WRITE,
7678 FALSE, VM_KERN_MEMORY_NONE,
7679 THREAD_UNINT, NULL, 0);
7680 if (kr != KERN_SUCCESS) {
7681 // 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);
7682 }
7683 }
7684
7685 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7686 DEBUG4K_LOAD("copyin(0x%llx, 0x%lx)\n", load_result->all_image_info_addr, expected_all_image_infos_size);
7687 }
7688 ret = copyin((user_addr_t)load_result->all_image_info_addr,
7689 &all_image_infos,
7690 expected_all_image_infos_size);
7691 if (ret == 0 && all_image_infos.infos32.version >= DYLD_ALL_IMAGE_INFOS_ADDRESS_MINIMUM_VERSION) {
7692 user_addr_t notification_address;
7693 user_addr_t dyld_image_address;
7694 user_addr_t dyld_version_address;
7695 user_addr_t dyld_all_image_infos_address;
7696 user_addr_t dyld_slide_amount;
7697
7698 if (imgp->ip_flags & IMGPF_IS_64BIT_ADDR) {
7699 notification_address = (user_addr_t)all_image_infos.infos64.notification;
7700 dyld_image_address = (user_addr_t)all_image_infos.infos64.dyldImageLoadAddress;
7701 dyld_version_address = (user_addr_t)all_image_infos.infos64.dyldVersion;
7702 dyld_all_image_infos_address = (user_addr_t)all_image_infos.infos64.dyldAllImageInfosAddress;
7703 } else {
7704 notification_address = all_image_infos.infos32.notification;
7705 dyld_image_address = all_image_infos.infos32.dyldImageLoadAddress;
7706 dyld_version_address = all_image_infos.infos32.dyldVersion;
7707 dyld_all_image_infos_address = all_image_infos.infos32.dyldAllImageInfosAddress;
7708 }
7709
7710 /*
7711 * dyld statically sets up the all_image_infos in its Mach-O
7712 * binary at static link time, with pointers relative to its default
7713 * load address. Since ASLR might slide dyld before its first
7714 * instruction is executed, "dyld_slide_amount" tells us how far
7715 * dyld was loaded compared to its default expected load address.
7716 * All other pointers into dyld's image should be adjusted by this
7717 * amount. At some point later, dyld will fix up pointers to take
7718 * into account the slide, at which point the all_image_infos_address
7719 * field in the structure will match the runtime load address, and
7720 * "dyld_slide_amount" will be 0, if we were to consult it again.
7721 */
7722
7723 dyld_slide_amount = (user_addr_t)load_result->all_image_info_addr - dyld_all_image_infos_address;
7724
7725 #if 0
7726 kprintf("exec_prefault: 0x%016llx 0x%08x 0x%016llx 0x%016llx 0x%016llx 0x%016llx\n",
7727 (uint64_t)load_result->all_image_info_addr,
7728 all_image_infos.infos32.version,
7729 (uint64_t)notification_address,
7730 (uint64_t)dyld_image_address,
7731 (uint64_t)dyld_version_address,
7732 (uint64_t)dyld_all_image_infos_address);
7733 #endif
7734
7735 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7736 DEBUG4K_LOAD("notification_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)notification_address, (uint64_t)dyld_slide_amount);
7737 }
7738 kr = vm_fault(current_map(),
7739 vm_map_trunc_page(notification_address + dyld_slide_amount,
7740 vm_map_page_mask(current_map())),
7741 VM_PROT_READ | VM_PROT_EXECUTE,
7742 FALSE, VM_KERN_MEMORY_NONE,
7743 THREAD_UNINT, NULL, 0);
7744 if (kr != KERN_SUCCESS) {
7745 // 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);
7746 }
7747 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7748 DEBUG4K_LOAD("dyld_image_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)dyld_image_address, (uint64_t)dyld_slide_amount);
7749 }
7750 kr = vm_fault(current_map(),
7751 vm_map_trunc_page(dyld_image_address + dyld_slide_amount,
7752 vm_map_page_mask(current_map())),
7753 VM_PROT_READ | VM_PROT_EXECUTE,
7754 FALSE, VM_KERN_MEMORY_NONE,
7755 THREAD_UNINT, NULL, 0);
7756 if (kr != KERN_SUCCESS) {
7757 // 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);
7758 }
7759 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7760 DEBUG4K_LOAD("dyld_version_address 0x%llx dyld_slide_amount 0x%llx\n", (uint64_t)dyld_version_address, (uint64_t)dyld_slide_amount);
7761 }
7762 kr = vm_fault(current_map(),
7763 vm_map_trunc_page(dyld_version_address + dyld_slide_amount,
7764 vm_map_page_mask(current_map())),
7765 VM_PROT_READ,
7766 FALSE, VM_KERN_MEMORY_NONE,
7767 THREAD_UNINT, NULL, 0);
7768 if (kr != KERN_SUCCESS) {
7769 // 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);
7770 }
7771 if (vm_map_page_shift(current_map()) < (int)PAGE_SHIFT) {
7772 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);
7773 }
7774 kr = vm_fault(current_map(),
7775 vm_map_trunc_page(dyld_all_image_infos_address + dyld_slide_amount,
7776 vm_map_page_mask(current_map())),
7777 VM_PROT_READ | VM_PROT_WRITE,
7778 FALSE, VM_KERN_MEMORY_NONE,
7779 THREAD_UNINT, NULL, 0);
7780 if (kr != KERN_SUCCESS) {
7781 // 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);
7782 }
7783 }
7784 }
7785 }
7786
7787 static int
7788 sysctl_libmalloc_experiments SYSCTL_HANDLER_ARGS
7789 {
7790 #pragma unused(oidp, arg2, req)
7791 int changed;
7792 errno_t error;
7793 uint64_t value = os_atomic_load_wide(&libmalloc_experiment_factors, relaxed);
7794
7795 error = sysctl_io_number(req, value, sizeof(value), &value, &changed);
7796 if (error) {
7797 return error;
7798 }
7799
7800 if (changed) {
7801 os_atomic_store_wide(&libmalloc_experiment_factors, value, relaxed);
7802 }
7803
7804 return 0;
7805 }
7806
7807 EXPERIMENT_FACTOR_PROC(_kern, libmalloc_experiments, CTLTYPE_QUAD | CTLFLAG_RW, 0, 0, &sysctl_libmalloc_experiments, "A", "");
7808