1 /*
2 * Copyright (c) 2000-2025 Apple Computer, 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) 1991 NeXT Computer, Inc. All rights reserved.
29 *
30 * File: bsd/kern/kern_core.c
31 *
32 * This file contains machine independent code for performing core dumps.
33 *
34 */
35 #if CONFIG_COREDUMP || CONFIG_UCOREDUMP
36
37 #include <mach/vm_param.h>
38 #include <mach/thread_status.h>
39 #include <sys/content_protection.h>
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/signalvar.h>
43 #include <sys/resourcevar.h>
44 #include <sys/namei.h>
45 #include <sys/vnode_internal.h>
46 #include <sys/proc_internal.h>
47 #include <sys/kauth.h>
48 #include <sys/timeb.h>
49 #include <sys/times.h>
50 #include <sys/acct.h>
51 #include <sys/file_internal.h>
52 #include <sys/uio.h>
53 #include <sys/kernel.h>
54 #include <sys/stat.h>
55
56 #include <mach-o/loader.h>
57 #include <mach/vm_region.h>
58 #include <mach/vm_statistics.h>
59
60 #include <IOKit/IOBSD.h>
61
62 #include <vm/vm_kern_xnu.h>
63 #include <vm/vm_protos.h> /* last */
64 #include <vm/vm_map_xnu.h> /* current_map() */
65 #include <vm/pmap.h> /* pmap_user_va_bits() */
66 #include <mach/mach_vm.h> /* mach_vm_region_recurse() */
67 #include <mach/task.h> /* task_suspend() */
68 #include <kern/task.h> /* get_task_numacts() */
69
70 #include <security/audit/audit.h>
71
72 #if CONFIG_MACF
73 #include <security/mac_framework.h>
74 #endif /* CONFIG_MACF */
75
76
77 #include <kdp/core_notes.h>
78
79 extern int freespace_mb(vnode_t vp);
80
81 /* XXX not in a Mach header anywhere */
82 kern_return_t thread_getstatus(thread_t act, int flavor,
83 thread_state_t tstate, mach_msg_type_number_t *count);
84 void task_act_iterate_wth_args(task_t, void (*)(thread_t, void *), void *);
85
86 #ifdef SECURE_KERNEL
87 __XNU_PRIVATE_EXTERN int do_coredump = 0; /* default: don't dump cores */
88 #else
89 __XNU_PRIVATE_EXTERN int do_coredump = 1; /* default: dump cores */
90 #endif /* SECURE_KERNEL */
91 __XNU_PRIVATE_EXTERN int sugid_coredump = 0; /* default: but not SGUID binaries */
92
93 #if CONFIG_UCOREDUMP
94 __XNU_PRIVATE_EXTERN int do_ucoredump = 0; /* default: kernel does dumps */
95 #endif
96
97 /*
98 * is_coredump_eligible
99 *
100 * Determine if a core should even be dumped at all (by any mechanism)
101 *
102 * Does NOT include disk permission or space constraints
103 *
104 * core_proc Process to dump core [*] must be current proc!
105 *
106 * Return: 0 Success
107 * !0 Failure errno
108 */
109 int
is_coredump_eligible(proc_t core_proc)110 is_coredump_eligible(proc_t core_proc)
111 {
112 if (current_proc() != core_proc && (
113 core_proc->p_exit_reason &&
114 core_proc->p_exit_reason->osr_namespace == OS_REASON_JETSAM)) {
115 return EPERM;
116 }
117 if (current_proc() != core_proc) {
118 panic("coredump for proc that is not current: %p)", core_proc);
119 }
120
121 vfs_context_t ctx = vfs_context_current();
122 kauth_cred_t cred = vfs_context_ucred(ctx);
123
124 if (do_coredump == 0 || /* Not dumping at all */
125 ((sugid_coredump == 0) && /* Not dumping SUID/SGID binaries */
126 ((kauth_cred_getsvuid(cred) != kauth_cred_getruid(cred)) ||
127 (kauth_cred_getsvgid(cred) != kauth_cred_getrgid(cred))))) {
128 return EPERM;
129 }
130
131 #if CONFIG_MACF
132 const int error = mac_proc_check_dump_core(core_proc);
133 if (error != 0) {
134 return error;
135 }
136 #endif
137 return 0;
138 }
139
140 #else /* CONFIG_COREDUMP || CONFIG_UCOREDUMP */
141
142 /* When core dumps aren't needed, no need to compile this file at all */
143
144 #error assertion failed: this section is not compiled
145
146 #endif /* CONFIG_COREDUMP || CONFIG_UCOREDUMP */
147
148 #if CONFIG_COREDUMP
149
150 #define COREDUMP_CUSTOM_LOCATION_ENTITLEMENT "com.apple.private.custom-coredump-location"
151
152 typedef struct {
153 int flavor; /* the number for this flavor */
154 mach_msg_type_number_t count; /* count of ints in this flavor */
155 } mythread_state_flavor_t;
156
157 #if defined (__i386__) || defined (__x86_64__)
158 mythread_state_flavor_t thread_flavor_array[] = {
159 {x86_THREAD_STATE, x86_THREAD_STATE_COUNT},
160 {x86_FLOAT_STATE, x86_FLOAT_STATE_COUNT},
161 {x86_EXCEPTION_STATE, x86_EXCEPTION_STATE_COUNT},
162 };
163 int mynum_flavors = 3;
164 #elif defined (__arm64__)
165 mythread_state_flavor_t thread_flavor_array[] = {
166 {ARM_THREAD_STATE64, ARM_THREAD_STATE64_COUNT},
167 /* ARM64_TODO: VFP */
168 {ARM_EXCEPTION_STATE64, ARM_EXCEPTION_STATE64_COUNT}
169 };
170 int mynum_flavors = 2;
171 #else
172 #error architecture not supported
173 #endif
174
175
176 typedef struct {
177 vm_offset_t header;
178 size_t hoffset;
179 mythread_state_flavor_t *flavors;
180 size_t tstate_size;
181 size_t flavor_count;
182 } tir_t;
183
184 /* cpu_type returns only the most generic indication of the current CPU. */
185 /* in a core we want to know the kind of process. */
186
187 cpu_type_t
process_cpu_type(proc_t core_proc)188 process_cpu_type(proc_t core_proc)
189 {
190 cpu_type_t what_we_think;
191 #if defined (__i386__) || defined (__x86_64__)
192 if (IS_64BIT_PROCESS(core_proc)) {
193 what_we_think = CPU_TYPE_X86_64;
194 } else {
195 what_we_think = CPU_TYPE_I386;
196 }
197 #elif defined(__arm64__)
198 if (IS_64BIT_PROCESS(core_proc)) {
199 what_we_think = CPU_TYPE_ARM64;
200 } else {
201 what_we_think = CPU_TYPE_ARM;
202 }
203 #endif
204
205 return what_we_think;
206 }
207
208 cpu_type_t
process_cpu_subtype(proc_t core_proc)209 process_cpu_subtype(proc_t core_proc)
210 {
211 cpu_type_t what_we_think;
212 #if defined (__i386__) || defined (__x86_64__)
213 if (IS_64BIT_PROCESS(core_proc)) {
214 what_we_think = CPU_SUBTYPE_X86_64_ALL;
215 } else {
216 what_we_think = CPU_SUBTYPE_I386_ALL;
217 }
218 #elif defined(__arm64__)
219 if (IS_64BIT_PROCESS(core_proc)) {
220 what_we_think = CPU_SUBTYPE_ARM64_ALL;
221 } else {
222 what_we_think = CPU_SUBTYPE_ARM_ALL;
223 }
224 #endif
225 return what_we_think;
226 }
227
228 static void
collectth_state(thread_t th_act,void * tirp)229 collectth_state(thread_t th_act, void *tirp)
230 {
231 vm_offset_t header;
232 size_t hoffset, i;
233 mythread_state_flavor_t *flavors;
234 struct thread_command *tc;
235 tir_t *t = (tir_t *)tirp;
236
237 /*
238 * Fill in thread command structure.
239 */
240 header = t->header;
241 hoffset = t->hoffset;
242 flavors = t->flavors;
243
244 tc = (struct thread_command *) (header + hoffset);
245 tc->cmd = LC_THREAD;
246 tc->cmdsize = (uint32_t)(sizeof(struct thread_command)
247 + t->tstate_size);
248 hoffset += sizeof(struct thread_command);
249 /*
250 * Follow with a struct thread_state_flavor and
251 * the appropriate thread state struct for each
252 * thread state flavor.
253 */
254 for (i = 0; i < t->flavor_count; i++) {
255 *(mythread_state_flavor_t *)(header + hoffset) =
256 flavors[i];
257 hoffset += sizeof(mythread_state_flavor_t);
258 thread_getstatus(th_act, flavors[i].flavor,
259 (thread_state_t)(header + hoffset),
260 &flavors[i].count);
261 hoffset += flavors[i].count * sizeof(int);
262 }
263
264 t->hoffset = hoffset;
265 }
266
267 #if DEVELOPMENT || DEBUG
268 #define COREDUMPLOG(fmt, args...) printf("coredump (%s, pid %d): " fmt "\n", core_proc->p_comm, proc_getpid(core_proc), ## args)
269 #else
270 #define COREDUMPLOG(fmt, args...)
271 #endif
272
273 /*
274 * LC_NOTE support for userspace coredumps.
275 */
276
277 typedef int (write_note_cb_t)(struct vnode *vp, off_t foffset);
278
279 static int
note_addrable_bits(struct vnode * vp,off_t foffset)280 note_addrable_bits(struct vnode *vp, off_t foffset)
281 {
282 task_t t = current_task();
283 vfs_context_t ctx = vfs_context_current();
284 kauth_cred_t cred = vfs_context_ucred(ctx);
285
286 addrable_bits_note_t note = {
287 .version = ADDRABLE_BITS_VER,
288 .addressing_bits = pmap_user_va_bits(get_task_pmap(t)),
289 .unused = 0
290 };
291
292 return vn_rdwr_64(UIO_WRITE, vp, (vm_offset_t)¬e, sizeof(note), foffset, UIO_SYSSPACE,
293 IO_NODELOCKED | IO_UNIT, cred, 0, current_proc());
294 }
295
296 /*
297 * note handling
298 */
299
300 struct core_note {
301 size_t cn_size;
302 const char *cn_owner;
303 write_note_cb_t *cn_write_cb;
304 } const core_notes[] = {
305 {
306 .cn_size = sizeof(addrable_bits_note_t),
307 .cn_owner = ADDRABLE_BITS_DATA_OWNER,
308 .cn_write_cb = note_addrable_bits,
309 }
310 };
311
312 const size_t notes_count = sizeof(core_notes) / sizeof(struct core_note);
313
314 /*
315 * LC_NOTE commands are allocated as a part of Mach-O header and are written to
316 * disk at the end of coredump. LC_NOTE's payload has to be written in callbacks here.
317 */
318 static int
dump_notes(proc_t __unused core_proc,vm_offset_t header,size_t hoffset,struct vnode * vp,off_t foffset)319 dump_notes(proc_t __unused core_proc, vm_offset_t header, size_t hoffset, struct vnode *vp, off_t foffset)
320 {
321 for (size_t i = 0; i < notes_count; i++) {
322 int error = 0;
323
324 if (core_notes[i].cn_write_cb == NULL) {
325 continue;
326 }
327
328 /* Generate LC_NOTE command. */
329 struct note_command *nc = (struct note_command *)(header + hoffset);
330
331 nc->cmd = LC_NOTE;
332 nc->cmdsize = sizeof(struct note_command);
333 nc->offset = foffset;
334 nc->size = core_notes[i].cn_size;
335 strlcpy(nc->data_owner, core_notes[i].cn_owner, sizeof(nc->data_owner));
336
337 hoffset += sizeof(struct note_command);
338
339 /* Add note's payload. */
340 error = core_notes[i].cn_write_cb(vp, foffset);
341 if (error != KERN_SUCCESS) {
342 COREDUMPLOG("failed to write LC_NOTE %s: error %d", core_notes[i].cn_owner, error);
343 return error;
344 }
345
346 foffset += core_notes[i].cn_size;
347 }
348
349 return 0;
350 }
351
352 /*
353 * coredump
354 *
355 * Description: Create a core image on the file "core" for the process
356 * indicated
357 *
358 * Parameters: core_proc Process to dump core [*]
359 * reserve_mb If non-zero, leave filesystem with
360 * at least this much free space.
361 * coredump_flags Extra options (ignore rlimit, run fsync)
362 *
363 * Returns: 0 Success
364 * !0 Failure errno
365 *
366 * IMPORTANT: This function can only be called on the current process, due
367 * to assumptions below; see variable declaration section for
368 * details.
369 */
370 #define MAX_TSTATE_FLAVORS 10
371 int
coredump(proc_t core_proc,uint32_t reserve_mb,int coredump_flags)372 coredump(proc_t core_proc, uint32_t reserve_mb, int coredump_flags)
373 {
374 /* Begin assumptions that limit us to only the current process */
375 vfs_context_t ctx = vfs_context_current();
376 vm_map_t map = current_map();
377 task_t task = current_task();
378 /* End assumptions */
379 kauth_cred_t cred = vfs_context_ucred(ctx);
380 int error = 0;
381 struct vnode_attr *vap = NULL;
382 size_t thread_count, segment_count;
383 size_t command_size, header_size, tstate_size;
384 size_t hoffset;
385 off_t foffset;
386 mach_vm_offset_t vmoffset;
387 vm_offset_t header;
388 mach_vm_size_t vmsize;
389 vm_prot_t prot;
390 vm_prot_t maxprot;
391 int error1 = 0;
392 char stack_name[MAXCOMLEN + 6];
393 char *alloced_name = NULL;
394 char *name = NULL;
395 mythread_state_flavor_t flavors[MAX_TSTATE_FLAVORS];
396 vm_size_t mapsize;
397 size_t i;
398 uint32_t nesting_depth = 0;
399 kern_return_t kret;
400 struct vm_region_submap_info_64 vbr;
401 mach_msg_type_number_t vbrcount = 0;
402 tir_t tir1;
403 struct vnode * vp;
404 struct mach_header *mh = NULL; /* protected by is_64 */
405 struct mach_header_64 *mh64 = NULL; /* protected by is_64 */
406 int is_64 = 0;
407 size_t mach_header_sz = sizeof(struct mach_header);
408 size_t segment_command_sz = sizeof(struct segment_command);
409 size_t notes_size = 0;
410 const char *format = NULL;
411 char *custom_location_entitlement = NULL;
412 size_t custom_location_entitlement_len = 0;
413 char *alloced_format = NULL;
414 size_t alloced_format_len = 0;
415 bool include_iokit_memory = task_is_driver(task);
416 bool coredump_attempted = false;
417
418 if ((error = is_coredump_eligible(core_proc)) != 0) {
419 goto out2;
420 }
421
422 if (IS_64BIT_PROCESS(core_proc)) {
423 is_64 = 1;
424 mach_header_sz = sizeof(struct mach_header_64);
425 segment_command_sz = sizeof(struct segment_command_64);
426 }
427
428 mapsize = get_vmmap_size(map);
429
430 custom_location_entitlement = IOCurrentTaskGetEntitlement(COREDUMP_CUSTOM_LOCATION_ENTITLEMENT);
431 if (custom_location_entitlement != NULL) {
432 custom_location_entitlement_len = strlen(custom_location_entitlement);
433 const char * dirname;
434 if (proc_is_driver(core_proc)) {
435 dirname = defaultdrivercorefiledir;
436 } else {
437 dirname = defaultcorefiledir;
438 }
439 size_t dirname_len = strlen(dirname);
440 size_t printed_len;
441
442 /* new format is dirname + "/" + string from entitlement */
443 alloced_format_len = dirname_len + 1 + custom_location_entitlement_len;
444 alloced_format = kalloc_data(alloced_format_len + 1, Z_ZERO | Z_WAITOK | Z_NOFAIL);
445 printed_len = snprintf(alloced_format, alloced_format_len + 1, "%s/%s", dirname, custom_location_entitlement);
446 assert(printed_len == alloced_format_len);
447
448 format = alloced_format;
449 } else {
450 if (proc_is_driver(core_proc)) {
451 format = drivercorefilename;
452 } else {
453 format = corefilename;
454 }
455 }
456
457 if (((coredump_flags & COREDUMP_IGNORE_ULIMIT) == 0) &&
458 (mapsize >= proc_limitgetcur(core_proc, RLIMIT_CORE))) {
459 error = EFAULT;
460 goto out2;
461 }
462
463 /* log coredump failures from here */
464 coredump_attempted = true;
465
466 (void) task_suspend_internal(task);
467
468
469 alloced_name = zalloc_flags(ZV_NAMEI, Z_NOWAIT | Z_ZERO);
470
471 /* create name according to sysctl'able format string */
472 /* if name creation fails, fall back to historical behaviour... */
473 if (alloced_name == NULL ||
474 proc_core_name(format, core_proc->p_comm, kauth_cred_getuid(cred),
475 proc_getpid(core_proc), alloced_name, MAXPATHLEN)) {
476 snprintf(stack_name, sizeof(stack_name),
477 "/cores/core.%d", proc_getpid(core_proc));
478 name = stack_name;
479 } else {
480 name = alloced_name;
481 }
482
483 COREDUMPLOG("writing core to %s", name);
484 if ((error = vnode_open(name, (O_CREAT | FWRITE | O_NOFOLLOW), S_IRUSR, VNODE_LOOKUP_NOFOLLOW, &vp, ctx))) {
485 COREDUMPLOG("failed to open core dump file %s: error %d", name, error);
486 goto out2;
487 }
488
489 vap = kalloc_type(struct vnode_attr, Z_WAITOK | Z_ZERO);
490 VATTR_INIT(vap);
491 VATTR_WANTED(vap, va_nlink);
492 /* Don't dump to non-regular files or files with links. */
493 if (vp->v_type != VREG ||
494 vnode_getattr(vp, vap, ctx) || vap->va_nlink != 1) {
495 COREDUMPLOG("failed to write core to non-regular file");
496 error = EFAULT;
497 goto out;
498 }
499
500 VATTR_INIT(vap); /* better to do it here than waste more stack in vnode_setsize */
501 VATTR_SET(vap, va_data_size, 0);
502 if (core_proc == initproc) {
503 VATTR_SET(vap, va_dataprotect_class, PROTECTION_CLASS_D);
504 }
505 vnode_setattr(vp, vap, ctx);
506 core_proc->p_acflag |= ACORE;
507
508 COREDUMPLOG("map size: %lu", mapsize);
509 if ((reserve_mb > 0) &&
510 ((freespace_mb(vp) - (mapsize >> 20)) < reserve_mb)) {
511 COREDUMPLOG("insufficient free space (free=%d MB, needed=%lu MB, reserve=%d MB)", freespace_mb(vp), (mapsize >> 20), reserve_mb);
512 error = ENOSPC;
513 goto out;
514 }
515
516 /*
517 * If the task is modified while dumping the file
518 * (e.g., changes in threads or VM, the resulting
519 * file will not necessarily be correct.
520 */
521
522 thread_count = get_task_numacts(task);
523 segment_count = get_vmmap_entries(map); /* XXX */
524 tir1.flavor_count = sizeof(thread_flavor_array) / sizeof(mythread_state_flavor_t);
525 bcopy(thread_flavor_array, flavors, sizeof(thread_flavor_array));
526 tstate_size = 0;
527 for (i = 0; i < tir1.flavor_count; i++) {
528 tstate_size += sizeof(mythread_state_flavor_t) +
529 (flavors[i].count * sizeof(int));
530 }
531
532 {
533 size_t lhs;
534 size_t rhs;
535
536 /* lhs = segment_count * segment_command_sz */
537 if (os_mul_overflow(segment_count, segment_command_sz, &lhs)) {
538 COREDUMPLOG("error: segment size overflow: segment_count=%lu, segment_command_sz=%lu", segment_count, segment_command_sz);
539 error = ENOMEM;
540 goto out;
541 }
542
543 /* rhs = (tstate_size + sizeof(struct thread_command)) * thread_count */
544 if (os_add_and_mul_overflow(tstate_size, sizeof(struct thread_command), thread_count, &rhs)) {
545 COREDUMPLOG("error: thread state size overflow: tstate_size=%lu, thread_count=%lu", tstate_size, thread_count);
546 error = ENOMEM;
547 goto out;
548 }
549
550 /* command_size = lhs + rhs */
551 if (os_add_overflow(lhs, rhs, &command_size)) {
552 COREDUMPLOG("error: command size overflow: lhs=%lu, rhs=%lu", lhs, rhs);
553 error = ENOMEM;
554 goto out;
555 }
556
557 /* Add notes payload. */
558 if (os_mul_overflow(notes_count, sizeof(struct note_command), ¬es_size)) {
559 COREDUMPLOG("error: note command size overflow: note=%lu", i);
560 error = ENOMEM;
561 goto out;
562 }
563
564 if (os_add_overflow(command_size, notes_size, &command_size)) {
565 COREDUMPLOG("error: notes overflow: notes_size=%lu", notes_size);
566 error = ENOMEM;
567 goto out;
568 }
569 }
570
571 if (os_add_overflow(command_size, mach_header_sz, &header_size)) {
572 COREDUMPLOG("error: header size overflow: command_size=%lu, mach_header_sz=%lu", command_size, mach_header_sz);
573 error = ENOMEM;
574 goto out;
575 }
576
577 if (kmem_alloc(kernel_map, &header, (vm_size_t)header_size,
578 KMA_DATA | KMA_ZERO, VM_KERN_MEMORY_DIAG) != KERN_SUCCESS) {
579 COREDUMPLOG("error: failed to allocate memory for header (size=%lu)", header_size);
580 error = ENOMEM;
581 goto out;
582 }
583
584 /*
585 * Set up Mach-O header.
586 */
587 if (is_64) {
588 mh64 = (struct mach_header_64 *)header;
589 mh64->magic = MH_MAGIC_64;
590 mh64->cputype = process_cpu_type(core_proc);
591 mh64->cpusubtype = process_cpu_subtype(core_proc);
592 mh64->filetype = MH_CORE;
593 mh64->ncmds = (uint32_t)(segment_count + notes_count + thread_count);
594 mh64->sizeofcmds = (uint32_t)command_size;
595 } else {
596 mh = (struct mach_header *)header;
597 mh->magic = MH_MAGIC;
598 mh->cputype = process_cpu_type(core_proc);
599 mh->cpusubtype = process_cpu_subtype(core_proc);
600 mh->filetype = MH_CORE;
601 mh->ncmds = (uint32_t)(segment_count + notes_count + thread_count);
602 mh->sizeofcmds = (uint32_t)command_size;
603 }
604
605 hoffset = mach_header_sz; /* offset into header */
606 foffset = round_page(header_size); /* offset into file */
607 vmoffset = MACH_VM_MIN_ADDRESS; /* offset into VM */
608 COREDUMPLOG("mach header size: %zu", header_size);
609
610 /*
611 * We use to check for an error, here, now we try and get
612 * as much as we can
613 */
614 COREDUMPLOG("dumping %zu segments", segment_count);
615 while (segment_count > 0) {
616 struct segment_command *sc;
617 struct segment_command_64 *sc64;
618
619 /*
620 * Get region information for next region.
621 */
622
623 while (1) {
624 vbrcount = VM_REGION_SUBMAP_INFO_COUNT_64;
625 if ((kret = mach_vm_region_recurse(map,
626 &vmoffset, &vmsize, &nesting_depth,
627 (vm_region_recurse_info_t)&vbr,
628 &vbrcount)) != KERN_SUCCESS) {
629 break;
630 }
631 /*
632 * If we get a valid mapping back, but we're dumping
633 * a 32 bit process, and it's over the allowable
634 * address space of a 32 bit process, it's the same
635 * as if mach_vm_region_recurse() failed.
636 */
637 if (!(is_64) &&
638 (vmoffset + vmsize > VM_MAX_ADDRESS)) {
639 kret = KERN_INVALID_ADDRESS;
640 COREDUMPLOG("exceeded allowable region for 32-bit process");
641 break;
642 }
643 if (vbr.is_submap) {
644 nesting_depth++;
645 continue;
646 } else {
647 break;
648 }
649 }
650 if (kret != KERN_SUCCESS) {
651 COREDUMPLOG("ending segment dump, kret=%d", kret);
652 break;
653 }
654
655 prot = vbr.protection;
656 maxprot = vbr.max_protection;
657
658 if ((prot | maxprot) == VM_PROT_NONE) {
659 /*
660 * Elide unreadable (likely reserved) segments
661 */
662 COREDUMPLOG("eliding unreadable segment %llx->%llx", vmoffset, vmoffset + vmsize);
663 vmoffset += vmsize;
664 continue;
665 }
666
667 /*
668 * Try as hard as possible to get read access to the data.
669 */
670 if ((prot & VM_PROT_READ) == 0) {
671 mach_vm_protect(map, vmoffset, vmsize, FALSE,
672 prot | VM_PROT_READ);
673 }
674
675 /*
676 * But only try and perform the write if we can read it.
677 */
678 int64_t fsize = ((maxprot & VM_PROT_READ) == VM_PROT_READ
679 && (include_iokit_memory || vbr.user_tag != VM_MEMORY_IOKIT)
680 && coredumpok(map, vmoffset)) ? vmsize : 0;
681
682 if (fsize) {
683 int64_t resid = 0;
684 const enum uio_seg sflg = IS_64BIT_PROCESS(core_proc) ?
685 UIO_USERSPACE64 : UIO_USERSPACE32;
686
687 error = vn_rdwr_64(UIO_WRITE, vp, vmoffset, fsize,
688 foffset, sflg, IO_NODELOCKED | IO_UNIT,
689 cred, &resid, core_proc);
690
691 if (error) {
692 /*
693 * Mark segment as empty
694 */
695 fsize = 0;
696 COREDUMPLOG("failed to write segment %llx->%llx: error %d", vmoffset, vmoffset + vmsize, error);
697 } else if (resid) {
698 /*
699 * Partial write. Extend the file size so
700 * that the segment command contains a valid
701 * range of offsets, possibly creating a hole.
702 */
703 VATTR_INIT(vap);
704 VATTR_SET(vap, va_data_size, foffset + fsize);
705 vnode_setattr(vp, vap, ctx);
706 COREDUMPLOG("partially wrote segment %llx->%llx, resid %lld", vmoffset, vmoffset + vmsize, resid);
707 }
708 } else {
709 COREDUMPLOG("skipping unreadable segment %llx->%llx", vmoffset, vmoffset + vmsize);
710 }
711
712 /*
713 * Fill in segment command structure.
714 */
715
716 if (is_64) {
717 sc64 = (struct segment_command_64 *)(header + hoffset);
718 sc64->cmd = LC_SEGMENT_64;
719 sc64->cmdsize = sizeof(struct segment_command_64);
720 /* segment name is zeroed by kmem_alloc */
721 sc64->segname[0] = 0;
722 sc64->vmaddr = vmoffset;
723 sc64->vmsize = vmsize;
724 sc64->fileoff = foffset;
725 sc64->filesize = fsize;
726 sc64->maxprot = maxprot;
727 sc64->initprot = prot;
728 sc64->nsects = 0;
729 sc64->flags = 0;
730 } else {
731 sc = (struct segment_command *) (header + hoffset);
732 sc->cmd = LC_SEGMENT;
733 sc->cmdsize = sizeof(struct segment_command);
734 /* segment name is zeroed by kmem_alloc */
735 sc->segname[0] = 0;
736 sc->vmaddr = CAST_DOWN_EXPLICIT(uint32_t, vmoffset);
737 sc->vmsize = CAST_DOWN_EXPLICIT(uint32_t, vmsize);
738 sc->fileoff = CAST_DOWN_EXPLICIT(uint32_t, foffset); /* will never truncate */
739 sc->filesize = CAST_DOWN_EXPLICIT(uint32_t, fsize); /* will never truncate */
740 sc->maxprot = maxprot;
741 sc->initprot = prot;
742 sc->nsects = 0;
743 sc->flags = 0;
744 }
745
746 hoffset += segment_command_sz;
747 foffset += fsize;
748 vmoffset += vmsize;
749 segment_count--;
750 }
751 COREDUMPLOG("max file offset: %lld", foffset);
752
753 /*
754 * If there are remaining segments which have not been written
755 * out because break in the loop above, then they were not counted
756 * because they exceed the real address space of the executable
757 * type: remove them from the header's count. This is OK, since
758 * we are allowed to have a sparse area following the segments.
759 */
760 if (is_64) {
761 mh64->ncmds -= segment_count;
762 mh64->sizeofcmds -= segment_count * segment_command_sz;
763 } else {
764 mh->ncmds -= segment_count;
765 mh->sizeofcmds -= segment_count * segment_command_sz;
766 }
767
768 /* Add LC_NOTES */
769 COREDUMPLOG("dumping %zu notes", notes_count);
770 if (dump_notes(core_proc, header, hoffset, vp, foffset) != 0) {
771 error = EFAULT;
772 goto out;
773 }
774
775 tir1.header = header;
776 tir1.hoffset = hoffset + notes_size;
777 tir1.flavors = flavors;
778 tir1.tstate_size = tstate_size;
779 COREDUMPLOG("dumping %zu threads", thread_count);
780 task_act_iterate_wth_args(task, collectth_state, &tir1);
781
782 /*
783 * Write out the Mach header at the beginning of the
784 * file. OK to use a 32 bit write for this.
785 */
786 error = vn_rdwr(UIO_WRITE, vp, (caddr_t)header, (int)MIN(header_size, INT_MAX), (off_t)0,
787 UIO_SYSSPACE, IO_NODELOCKED | IO_UNIT, cred, (int *) 0, core_proc);
788 if (error != KERN_SUCCESS) {
789 COREDUMPLOG("failed to write mach header: error %d", error);
790 }
791 kmem_free(kernel_map, header, header_size);
792
793 if ((coredump_flags & COREDUMP_FULLFSYNC) && error == 0) {
794 error = VNOP_IOCTL(vp, F_FULLFSYNC, (caddr_t)NULL, 0, ctx);
795 if (error != KERN_SUCCESS) {
796 COREDUMPLOG("failed to FULLFSYNC core: error %d", error);
797 }
798 }
799 out:
800 if (vap) {
801 kfree_type(struct vnode_attr, vap);
802 }
803 error1 = vnode_close(vp, FWRITE, ctx);
804 if (error1 != KERN_SUCCESS) {
805 COREDUMPLOG("failed to close core file: error %d", error1);
806 }
807 out2:
808 #if CONFIG_AUDIT
809 audit_proc_coredump(core_proc, name, error);
810 #endif
811 if (alloced_name != NULL) {
812 zfree(ZV_NAMEI, alloced_name);
813 }
814 if (alloced_format != NULL) {
815 kfree_data(alloced_format, alloced_format_len + 1);
816 }
817 if (custom_location_entitlement != NULL) {
818 kfree_data(custom_location_entitlement, custom_location_entitlement_len + 1);
819 }
820 if (error == 0) {
821 error = error1;
822 }
823
824 if (coredump_attempted) {
825 if (error != 0) {
826 COREDUMPLOG("core dump failed: error %d\n", error);
827 } else {
828 COREDUMPLOG("core dump succeeded");
829 }
830 }
831
832 return error;
833 }
834
835 #endif /* CONFIG_COREDUMP */
836