1 //===-- sanitizer_mac.cpp -------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file is shared between various sanitizers' runtime libraries and
10 // implements OSX-specific functions.
11 //===----------------------------------------------------------------------===//
12
13 #include "sanitizer_platform.h"
14 #if SANITIZER_MAC
15 #include "sanitizer_mac.h"
16 #include "interception/interception.h"
17
18 // Use 64-bit inodes in file operations. ASan does not support OS X 10.5, so
19 // the clients will most certainly use 64-bit ones as well.
20 #ifndef _DARWIN_USE_64_BIT_INODE
21 #define _DARWIN_USE_64_BIT_INODE 1
22 #endif
23 #include <stdio.h>
24
25 #include "sanitizer_common.h"
26 #include "sanitizer_file.h"
27 #include "sanitizer_flags.h"
28 #include "sanitizer_internal_defs.h"
29 #include "sanitizer_libc.h"
30 #include "sanitizer_platform_limits_posix.h"
31 #include "sanitizer_procmaps.h"
32 #include "sanitizer_ptrauth.h"
33
34 #if !SANITIZER_IOS
35 #include <crt_externs.h> // for _NSGetEnviron
36 #else
37 extern char **environ;
38 #endif
39
40 #if defined(__has_include) && __has_include(<os/trace.h>)
41 #define SANITIZER_OS_TRACE 1
42 #include <os/trace.h>
43 #else
44 #define SANITIZER_OS_TRACE 0
45 #endif
46
47 // import new crash reporting api
48 #if defined(__has_include) && __has_include(<CrashReporterClient.h>)
49 #define HAVE_CRASHREPORTERCLIENT_H 1
50 #include <CrashReporterClient.h>
51 #else
52 #define HAVE_CRASHREPORTERCLIENT_H 0
53 #endif
54
55 #if !SANITIZER_IOS
56 #include <crt_externs.h> // for _NSGetArgv and _NSGetEnviron
57 #else
58 extern "C" {
59 extern char ***_NSGetArgv(void);
60 }
61 #endif
62
63 #include <asl.h>
64 #include <dlfcn.h> // for dladdr()
65 #include <errno.h>
66 #include <fcntl.h>
67 #include <libkern/OSAtomic.h>
68 #include <mach-o/dyld.h>
69 #include <mach/mach.h>
70 #include <mach/mach_time.h>
71 #include <mach/vm_statistics.h>
72 #include <malloc/malloc.h>
73 #include <os/log.h>
74 #include <pthread.h>
75 #include <sched.h>
76 #include <signal.h>
77 #include <spawn.h>
78 #include <stdlib.h>
79 #include <sys/ioctl.h>
80 #include <sys/mman.h>
81 #include <sys/resource.h>
82 #include <sys/stat.h>
83 #include <sys/sysctl.h>
84 #include <sys/types.h>
85 #include <sys/wait.h>
86 #include <unistd.h>
87 #include <util.h>
88
89 // From <crt_externs.h>, but we don't have that file on iOS.
90 extern "C" {
91 extern char ***_NSGetArgv(void);
92 extern char ***_NSGetEnviron(void);
93 }
94
95 // From <mach/mach_vm.h>, but we don't have that file on iOS.
96 extern "C" {
97 extern kern_return_t mach_vm_region_recurse(
98 vm_map_t target_task,
99 mach_vm_address_t *address,
100 mach_vm_size_t *size,
101 natural_t *nesting_depth,
102 vm_region_recurse_info_t info,
103 mach_msg_type_number_t *infoCnt);
104 }
105
106 namespace __sanitizer {
107
108 #include "sanitizer_syscall_generic.inc"
109
110 // Direct syscalls, don't call libmalloc hooks (but not available on 10.6).
111 extern "C" void *__mmap(void *addr, size_t len, int prot, int flags, int fildes,
112 off_t off) SANITIZER_WEAK_ATTRIBUTE;
113 extern "C" int __munmap(void *, size_t) SANITIZER_WEAK_ATTRIBUTE;
114
115 // ---------------------- sanitizer_libc.h
116
117 // From <mach/vm_statistics.h>, but not on older OSs.
118 #ifndef VM_MEMORY_SANITIZER
119 #define VM_MEMORY_SANITIZER 99
120 #endif
121
122 // XNU on Darwin provides a mmap flag that optimizes allocation/deallocation of
123 // giant memory regions (i.e. shadow memory regions).
124 #define kXnuFastMmapFd 0x4
125 static size_t kXnuFastMmapThreshold = 2 << 30; // 2 GB
126 static bool use_xnu_fast_mmap = false;
127
internal_mmap(void * addr,size_t length,int prot,int flags,int fd,u64 offset)128 uptr internal_mmap(void *addr, size_t length, int prot, int flags,
129 int fd, u64 offset) {
130 if (fd == -1) {
131 fd = VM_MAKE_TAG(VM_MEMORY_SANITIZER);
132 if (length >= kXnuFastMmapThreshold) {
133 if (use_xnu_fast_mmap) fd |= kXnuFastMmapFd;
134 }
135 }
136 if (&__mmap) return (uptr)__mmap(addr, length, prot, flags, fd, offset);
137 return (uptr)mmap(addr, length, prot, flags, fd, offset);
138 }
139
internal_munmap(void * addr,uptr length)140 uptr internal_munmap(void *addr, uptr length) {
141 if (&__munmap) return __munmap(addr, length);
142 return munmap(addr, length);
143 }
144
internal_mremap(void * old_address,uptr old_size,uptr new_size,int flags,void * new_address)145 uptr internal_mremap(void *old_address, uptr old_size, uptr new_size, int flags,
146 void *new_address) {
147 CHECK(false && "internal_mremap is unimplemented on Mac");
148 return 0;
149 }
150
internal_mprotect(void * addr,uptr length,int prot)151 int internal_mprotect(void *addr, uptr length, int prot) {
152 return mprotect(addr, length, prot);
153 }
154
internal_madvise(uptr addr,uptr length,int advice)155 int internal_madvise(uptr addr, uptr length, int advice) {
156 return madvise((void *)addr, length, advice);
157 }
158
internal_close(fd_t fd)159 uptr internal_close(fd_t fd) {
160 return close(fd);
161 }
162
internal_open(const char * filename,int flags)163 uptr internal_open(const char *filename, int flags) {
164 return open(filename, flags);
165 }
166
internal_open(const char * filename,int flags,u32 mode)167 uptr internal_open(const char *filename, int flags, u32 mode) {
168 return open(filename, flags, mode);
169 }
170
internal_read(fd_t fd,void * buf,uptr count)171 uptr internal_read(fd_t fd, void *buf, uptr count) {
172 return read(fd, buf, count);
173 }
174
internal_write(fd_t fd,const void * buf,uptr count)175 uptr internal_write(fd_t fd, const void *buf, uptr count) {
176 return write(fd, buf, count);
177 }
178
internal_stat(const char * path,void * buf)179 uptr internal_stat(const char *path, void *buf) {
180 return stat(path, (struct stat *)buf);
181 }
182
internal_lstat(const char * path,void * buf)183 uptr internal_lstat(const char *path, void *buf) {
184 return lstat(path, (struct stat *)buf);
185 }
186
internal_fstat(fd_t fd,void * buf)187 uptr internal_fstat(fd_t fd, void *buf) {
188 return fstat(fd, (struct stat *)buf);
189 }
190
internal_filesize(fd_t fd)191 uptr internal_filesize(fd_t fd) {
192 struct stat st;
193 if (internal_fstat(fd, &st))
194 return -1;
195 return (uptr)st.st_size;
196 }
197
internal_dup(int oldfd)198 uptr internal_dup(int oldfd) {
199 return dup(oldfd);
200 }
201
internal_dup2(int oldfd,int newfd)202 uptr internal_dup2(int oldfd, int newfd) {
203 return dup2(oldfd, newfd);
204 }
205
internal_readlink(const char * path,char * buf,uptr bufsize)206 uptr internal_readlink(const char *path, char *buf, uptr bufsize) {
207 return readlink(path, buf, bufsize);
208 }
209
internal_unlink(const char * path)210 uptr internal_unlink(const char *path) {
211 return unlink(path);
212 }
213
internal_sched_yield()214 uptr internal_sched_yield() {
215 return sched_yield();
216 }
217
internal__exit(int exitcode)218 void internal__exit(int exitcode) {
219 _exit(exitcode);
220 }
221
internal_usleep(u64 useconds)222 void internal_usleep(u64 useconds) { usleep(useconds); }
223
internal_getpid()224 uptr internal_getpid() {
225 return getpid();
226 }
227
internal_dlinfo(void * handle,int request,void * p)228 int internal_dlinfo(void *handle, int request, void *p) {
229 UNIMPLEMENTED();
230 }
231
internal_sigaction(int signum,const void * act,void * oldact)232 int internal_sigaction(int signum, const void *act, void *oldact) {
233 return sigaction(signum,
234 (const struct sigaction *)act, (struct sigaction *)oldact);
235 }
236
internal_sigfillset(__sanitizer_sigset_t * set)237 void internal_sigfillset(__sanitizer_sigset_t *set) { sigfillset(set); }
238
internal_sigprocmask(int how,__sanitizer_sigset_t * set,__sanitizer_sigset_t * oldset)239 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
240 __sanitizer_sigset_t *oldset) {
241 // Don't use sigprocmask here, because it affects all threads.
242 return pthread_sigmask(how, set, oldset);
243 }
244
245 // Doesn't call pthread_atfork() handlers (but not available on 10.6).
246 extern "C" pid_t __fork(void) SANITIZER_WEAK_ATTRIBUTE;
247
internal_fork()248 int internal_fork() {
249 if (&__fork)
250 return __fork();
251 return fork();
252 }
253
internal_sysctl(const int * name,unsigned int namelen,void * oldp,uptr * oldlenp,const void * newp,uptr newlen)254 int internal_sysctl(const int *name, unsigned int namelen, void *oldp,
255 uptr *oldlenp, const void *newp, uptr newlen) {
256 return sysctl(const_cast<int *>(name), namelen, oldp, (size_t *)oldlenp,
257 const_cast<void *>(newp), (size_t)newlen);
258 }
259
internal_sysctlbyname(const char * sname,void * oldp,uptr * oldlenp,const void * newp,uptr newlen)260 int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp,
261 const void *newp, uptr newlen) {
262 return sysctlbyname(sname, oldp, (size_t *)oldlenp, const_cast<void *>(newp),
263 (size_t)newlen);
264 }
265
internal_spawn_impl(const char * argv[],const char * envp[],pid_t * pid)266 static fd_t internal_spawn_impl(const char *argv[], const char *envp[],
267 pid_t *pid) {
268 fd_t master_fd = kInvalidFd;
269 fd_t slave_fd = kInvalidFd;
270
271 auto fd_closer = at_scope_exit([&] {
272 internal_close(master_fd);
273 internal_close(slave_fd);
274 });
275
276 // We need a new pseudoterminal to avoid buffering problems. The 'atos' tool
277 // in particular detects when it's talking to a pipe and forgets to flush the
278 // output stream after sending a response.
279 master_fd = posix_openpt(O_RDWR);
280 if (master_fd == kInvalidFd) return kInvalidFd;
281
282 int res = grantpt(master_fd) || unlockpt(master_fd);
283 if (res != 0) return kInvalidFd;
284
285 // Use TIOCPTYGNAME instead of ptsname() to avoid threading problems.
286 char slave_pty_name[128];
287 res = ioctl(master_fd, TIOCPTYGNAME, slave_pty_name);
288 if (res == -1) return kInvalidFd;
289
290 slave_fd = internal_open(slave_pty_name, O_RDWR);
291 if (slave_fd == kInvalidFd) return kInvalidFd;
292
293 // File descriptor actions
294 posix_spawn_file_actions_t acts;
295 res = posix_spawn_file_actions_init(&acts);
296 if (res != 0) return kInvalidFd;
297
298 auto acts_cleanup = at_scope_exit([&] {
299 posix_spawn_file_actions_destroy(&acts);
300 });
301
302 res = posix_spawn_file_actions_adddup2(&acts, slave_fd, STDIN_FILENO) ||
303 posix_spawn_file_actions_adddup2(&acts, slave_fd, STDOUT_FILENO) ||
304 posix_spawn_file_actions_addclose(&acts, slave_fd);
305 if (res != 0) return kInvalidFd;
306
307 // Spawn attributes
308 posix_spawnattr_t attrs;
309 res = posix_spawnattr_init(&attrs);
310 if (res != 0) return kInvalidFd;
311
312 auto attrs_cleanup = at_scope_exit([&] {
313 posix_spawnattr_destroy(&attrs);
314 });
315
316 // In the spawned process, close all file descriptors that are not explicitly
317 // described by the file actions object. This is Darwin-specific extension.
318 res = posix_spawnattr_setflags(&attrs, POSIX_SPAWN_CLOEXEC_DEFAULT);
319 if (res != 0) return kInvalidFd;
320
321 // posix_spawn
322 char **argv_casted = const_cast<char **>(argv);
323 char **envp_casted = const_cast<char **>(envp);
324 res = posix_spawn(pid, argv[0], &acts, &attrs, argv_casted, envp_casted);
325 if (res != 0) return kInvalidFd;
326
327 // Disable echo in the new terminal, disable CR.
328 struct termios termflags;
329 tcgetattr(master_fd, &termflags);
330 termflags.c_oflag &= ~ONLCR;
331 termflags.c_lflag &= ~ECHO;
332 tcsetattr(master_fd, TCSANOW, &termflags);
333
334 // On success, do not close master_fd on scope exit.
335 fd_t fd = master_fd;
336 master_fd = kInvalidFd;
337
338 return fd;
339 }
340
internal_spawn(const char * argv[],const char * envp[],pid_t * pid)341 fd_t internal_spawn(const char *argv[], const char *envp[], pid_t *pid) {
342 // The client program may close its stdin and/or stdout and/or stderr thus
343 // allowing open/posix_openpt to reuse file descriptors 0, 1 or 2. In this
344 // case the communication is broken if either the parent or the child tries to
345 // close or duplicate these descriptors. We temporarily reserve these
346 // descriptors here to prevent this.
347 fd_t low_fds[3];
348 size_t count = 0;
349
350 for (; count < 3; count++) {
351 low_fds[count] = posix_openpt(O_RDWR);
352 if (low_fds[count] >= STDERR_FILENO)
353 break;
354 }
355
356 fd_t fd = internal_spawn_impl(argv, envp, pid);
357
358 for (; count > 0; count--) {
359 internal_close(low_fds[count]);
360 }
361
362 return fd;
363 }
364
internal_rename(const char * oldpath,const char * newpath)365 uptr internal_rename(const char *oldpath, const char *newpath) {
366 return rename(oldpath, newpath);
367 }
368
internal_ftruncate(fd_t fd,uptr size)369 uptr internal_ftruncate(fd_t fd, uptr size) {
370 return ftruncate(fd, size);
371 }
372
internal_execve(const char * filename,char * const argv[],char * const envp[])373 uptr internal_execve(const char *filename, char *const argv[],
374 char *const envp[]) {
375 return execve(filename, argv, envp);
376 }
377
internal_waitpid(int pid,int * status,int options)378 uptr internal_waitpid(int pid, int *status, int options) {
379 return waitpid(pid, status, options);
380 }
381
382 // ----------------- sanitizer_common.h
FileExists(const char * filename)383 bool FileExists(const char *filename) {
384 if (ShouldMockFailureToOpen(filename))
385 return false;
386 struct stat st;
387 if (stat(filename, &st))
388 return false;
389 // Sanity check: filename is a regular file.
390 return S_ISREG(st.st_mode);
391 }
392
GetTid()393 tid_t GetTid() {
394 tid_t tid;
395 pthread_threadid_np(nullptr, &tid);
396 return tid;
397 }
398
GetThreadStackTopAndBottom(bool at_initialization,uptr * stack_top,uptr * stack_bottom)399 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
400 uptr *stack_bottom) {
401 CHECK(stack_top);
402 CHECK(stack_bottom);
403 uptr stacksize = pthread_get_stacksize_np(pthread_self());
404 // pthread_get_stacksize_np() returns an incorrect stack size for the main
405 // thread on Mavericks. See
406 // https://github.com/google/sanitizers/issues/261
407 if ((GetMacosAlignedVersion() >= MacosVersion(10, 9)) && at_initialization &&
408 stacksize == (1 << 19)) {
409 struct rlimit rl;
410 CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
411 // Most often rl.rlim_cur will be the desired 8M.
412 if (rl.rlim_cur < kMaxThreadStackSize) {
413 stacksize = rl.rlim_cur;
414 } else {
415 stacksize = kMaxThreadStackSize;
416 }
417 }
418 void *stackaddr = pthread_get_stackaddr_np(pthread_self());
419 *stack_top = (uptr)stackaddr;
420 *stack_bottom = *stack_top - stacksize;
421 }
422
GetEnviron()423 char **GetEnviron() {
424 #if !SANITIZER_IOS
425 char ***env_ptr = _NSGetEnviron();
426 if (!env_ptr) {
427 Report("_NSGetEnviron() returned NULL. Please make sure __asan_init() is "
428 "called after libSystem_initializer().\n");
429 CHECK(env_ptr);
430 }
431 char **environ = *env_ptr;
432 #endif
433 CHECK(environ);
434 return environ;
435 }
436
GetEnv(const char * name)437 const char *GetEnv(const char *name) {
438 char **env = GetEnviron();
439 uptr name_len = internal_strlen(name);
440 while (*env != 0) {
441 uptr len = internal_strlen(*env);
442 if (len > name_len) {
443 const char *p = *env;
444 if (!internal_memcmp(p, name, name_len) &&
445 p[name_len] == '=') { // Match.
446 return *env + name_len + 1; // String starting after =.
447 }
448 }
449 env++;
450 }
451 return 0;
452 }
453
ReadBinaryName(char * buf,uptr buf_len)454 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
455 CHECK_LE(kMaxPathLength, buf_len);
456
457 // On OS X the executable path is saved to the stack by dyld. Reading it
458 // from there is much faster than calling dladdr, especially for large
459 // binaries with symbols.
460 InternalMmapVector<char> exe_path(kMaxPathLength);
461 uint32_t size = exe_path.size();
462 if (_NSGetExecutablePath(exe_path.data(), &size) == 0 &&
463 realpath(exe_path.data(), buf) != 0) {
464 return internal_strlen(buf);
465 }
466 return 0;
467 }
468
ReadLongProcessName(char * buf,uptr buf_len)469 uptr ReadLongProcessName(/*out*/char *buf, uptr buf_len) {
470 return ReadBinaryName(buf, buf_len);
471 }
472
ReExec()473 void ReExec() {
474 UNIMPLEMENTED();
475 }
476
CheckASLR()477 void CheckASLR() {
478 // Do nothing
479 }
480
CheckMPROTECT()481 void CheckMPROTECT() {
482 // Do nothing
483 }
484
GetPageSize()485 uptr GetPageSize() {
486 return sysconf(_SC_PAGESIZE);
487 }
488
489 extern "C" unsigned malloc_num_zones;
490 extern "C" malloc_zone_t **malloc_zones;
491 malloc_zone_t sanitizer_zone;
492
493 // We need to make sure that sanitizer_zone is registered as malloc_zones[0]. If
494 // libmalloc tries to set up a different zone as malloc_zones[0], it will call
495 // mprotect(malloc_zones, ..., PROT_READ). This interceptor will catch that and
496 // make sure we are still the first (default) zone.
MprotectMallocZones(void * addr,int prot)497 void MprotectMallocZones(void *addr, int prot) {
498 if (addr == malloc_zones && prot == PROT_READ) {
499 if (malloc_num_zones > 1 && malloc_zones[0] != &sanitizer_zone) {
500 for (unsigned i = 1; i < malloc_num_zones; i++) {
501 if (malloc_zones[i] == &sanitizer_zone) {
502 // Swap malloc_zones[0] and malloc_zones[i].
503 malloc_zones[i] = malloc_zones[0];
504 malloc_zones[0] = &sanitizer_zone;
505 break;
506 }
507 }
508 }
509 }
510 }
511
FutexWait(atomic_uint32_t * p,u32 cmp)512 void FutexWait(atomic_uint32_t *p, u32 cmp) {
513 // FIXME: implement actual blocking.
514 sched_yield();
515 }
516
FutexWake(atomic_uint32_t * p,u32 count)517 void FutexWake(atomic_uint32_t *p, u32 count) {}
518
NanoTime()519 u64 NanoTime() {
520 timeval tv;
521 internal_memset(&tv, 0, sizeof(tv));
522 gettimeofday(&tv, 0);
523 return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000;
524 }
525
526 // This needs to be called during initialization to avoid being racy.
MonotonicNanoTime()527 u64 MonotonicNanoTime() {
528 static mach_timebase_info_data_t timebase_info;
529 if (timebase_info.denom == 0) mach_timebase_info(&timebase_info);
530 return (mach_absolute_time() * timebase_info.numer) / timebase_info.denom;
531 }
532
GetTlsSize()533 uptr GetTlsSize() {
534 return 0;
535 }
536
InitTlsSize()537 void InitTlsSize() {
538 }
539
TlsBaseAddr()540 uptr TlsBaseAddr() {
541 uptr segbase = 0;
542 #if defined(__x86_64__)
543 asm("movq %%gs:0,%0" : "=r"(segbase));
544 #elif defined(__i386__)
545 asm("movl %%gs:0,%0" : "=r"(segbase));
546 #endif
547 return segbase;
548 }
549
550 // The size of the tls on darwin does not appear to be well documented,
551 // however the vm memory map suggests that it is 1024 uptrs in size,
552 // with a size of 0x2000 bytes on x86_64 and 0x1000 bytes on i386.
TlsSize()553 uptr TlsSize() {
554 #if defined(__x86_64__) || defined(__i386__)
555 return 1024 * sizeof(uptr);
556 #else
557 return 0;
558 #endif
559 }
560
GetThreadStackAndTls(bool main,uptr * stk_addr,uptr * stk_size,uptr * tls_addr,uptr * tls_size)561 void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
562 uptr *tls_addr, uptr *tls_size) {
563 #if !SANITIZER_GO
564 uptr stack_top, stack_bottom;
565 GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
566 *stk_addr = stack_bottom;
567 *stk_size = stack_top - stack_bottom;
568 *tls_addr = TlsBaseAddr();
569 *tls_size = TlsSize();
570 #else
571 *stk_addr = 0;
572 *stk_size = 0;
573 *tls_addr = 0;
574 *tls_size = 0;
575 #endif
576 }
577
init()578 void ListOfModules::init() {
579 clearOrInit();
580 MemoryMappingLayout memory_mapping(false);
581 memory_mapping.DumpListOfModules(&modules_);
582 }
583
fallbackInit()584 void ListOfModules::fallbackInit() { clear(); }
585
GetHandleSignalModeImpl(int signum)586 static HandleSignalMode GetHandleSignalModeImpl(int signum) {
587 switch (signum) {
588 case SIGABRT:
589 return common_flags()->handle_abort;
590 case SIGILL:
591 return common_flags()->handle_sigill;
592 case SIGTRAP:
593 return common_flags()->handle_sigtrap;
594 case SIGFPE:
595 return common_flags()->handle_sigfpe;
596 case SIGSEGV:
597 return common_flags()->handle_segv;
598 case SIGBUS:
599 return common_flags()->handle_sigbus;
600 }
601 return kHandleSignalNo;
602 }
603
GetHandleSignalMode(int signum)604 HandleSignalMode GetHandleSignalMode(int signum) {
605 // Handling fatal signals on watchOS and tvOS devices is disallowed.
606 if ((SANITIZER_WATCHOS || SANITIZER_TVOS) && !(SANITIZER_IOSSIM))
607 return kHandleSignalNo;
608 HandleSignalMode result = GetHandleSignalModeImpl(signum);
609 if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler)
610 return kHandleSignalExclusive;
611 return result;
612 }
613
614 // Offset example:
615 // XNU 17 -- macOS 10.13 -- iOS 11 -- tvOS 11 -- watchOS 4
GetOSMajorKernelOffset()616 constexpr u16 GetOSMajorKernelOffset() {
617 if (TARGET_OS_OSX) return 4;
618 if (TARGET_OS_IOS || TARGET_OS_TV) return 6;
619 if (TARGET_OS_WATCH) return 13;
620 }
621
622 using VersStr = char[64];
623
ApproximateOSVersionViaKernelVersion(VersStr vers)624 static uptr ApproximateOSVersionViaKernelVersion(VersStr vers) {
625 u16 kernel_major = GetDarwinKernelVersion().major;
626 u16 offset = GetOSMajorKernelOffset();
627 CHECK_GE(kernel_major, offset);
628 u16 os_major = kernel_major - offset;
629
630 const char *format = "%d.0";
631 if (TARGET_OS_OSX) {
632 if (os_major >= 16) { // macOS 11+
633 os_major -= 5;
634 } else { // macOS 10.15 and below
635 format = "10.%d";
636 }
637 }
638 return internal_snprintf(vers, sizeof(VersStr), format, os_major);
639 }
640
GetOSVersion(VersStr vers)641 static void GetOSVersion(VersStr vers) {
642 uptr len = sizeof(VersStr);
643 if (SANITIZER_IOSSIM) {
644 const char *vers_env = GetEnv("SIMULATOR_RUNTIME_VERSION");
645 if (!vers_env) {
646 Report("ERROR: Running in simulator but SIMULATOR_RUNTIME_VERSION env "
647 "var is not set.\n");
648 Die();
649 }
650 len = internal_strlcpy(vers, vers_env, len);
651 } else {
652 int res =
653 internal_sysctlbyname("kern.osproductversion", vers, &len, nullptr, 0);
654
655 // XNU 17 (macOS 10.13) and below do not provide the sysctl
656 // `kern.osproductversion` entry (res != 0).
657 bool no_os_version = res != 0;
658
659 // For launchd, sanitizer initialization runs before sysctl is setup
660 // (res == 0 && len != strlen(vers), vers is not a valid version). However,
661 // the kernel version `kern.osrelease` is available.
662 bool launchd = (res == 0 && internal_strlen(vers) < 3);
663 if (launchd) CHECK_EQ(internal_getpid(), 1);
664
665 if (no_os_version || launchd) {
666 len = ApproximateOSVersionViaKernelVersion(vers);
667 }
668 }
669 CHECK_LT(len, sizeof(VersStr));
670 }
671
ParseVersion(const char * vers,u16 * major,u16 * minor)672 void ParseVersion(const char *vers, u16 *major, u16 *minor) {
673 // Format: <major>.<minor>[.<patch>]\0
674 CHECK_GE(internal_strlen(vers), 3);
675 const char *p = vers;
676 *major = internal_simple_strtoll(p, &p, /*base=*/10);
677 CHECK_EQ(*p, '.');
678 p += 1;
679 *minor = internal_simple_strtoll(p, &p, /*base=*/10);
680 }
681
682 // Aligned versions example:
683 // macOS 10.15 -- iOS 13 -- tvOS 13 -- watchOS 6
MapToMacos(u16 * major,u16 * minor)684 static void MapToMacos(u16 *major, u16 *minor) {
685 if (TARGET_OS_OSX)
686 return;
687
688 if (TARGET_OS_IOS || TARGET_OS_TV)
689 *major += 2;
690 else if (TARGET_OS_WATCH)
691 *major += 9;
692 else
693 UNREACHABLE("unsupported platform");
694
695 if (*major >= 16) { // macOS 11+
696 *major -= 5;
697 } else { // macOS 10.15 and below
698 *minor = *major;
699 *major = 10;
700 }
701 }
702
GetMacosAlignedVersionInternal()703 static MacosVersion GetMacosAlignedVersionInternal() {
704 VersStr vers = {};
705 GetOSVersion(vers);
706
707 u16 major, minor;
708 ParseVersion(vers, &major, &minor);
709 MapToMacos(&major, &minor);
710
711 return MacosVersion(major, minor);
712 }
713
714 static_assert(sizeof(MacosVersion) == sizeof(atomic_uint32_t::Type),
715 "MacosVersion cache size");
716 static atomic_uint32_t cached_macos_version;
717
GetMacosAlignedVersion()718 MacosVersion GetMacosAlignedVersion() {
719 atomic_uint32_t::Type result =
720 atomic_load(&cached_macos_version, memory_order_acquire);
721 if (!result) {
722 MacosVersion version = GetMacosAlignedVersionInternal();
723 result = *reinterpret_cast<atomic_uint32_t::Type *>(&version);
724 atomic_store(&cached_macos_version, result, memory_order_release);
725 }
726 return *reinterpret_cast<MacosVersion *>(&result);
727 }
728
GetDarwinKernelVersion()729 DarwinKernelVersion GetDarwinKernelVersion() {
730 VersStr vers = {};
731 uptr len = sizeof(VersStr);
732 int res = internal_sysctlbyname("kern.osrelease", vers, &len, nullptr, 0);
733 CHECK_EQ(res, 0);
734 CHECK_LT(len, sizeof(VersStr));
735
736 u16 major, minor;
737 ParseVersion(vers, &major, &minor);
738
739 return DarwinKernelVersion(major, minor);
740 }
741
GetRSS()742 uptr GetRSS() {
743 struct task_basic_info info;
744 unsigned count = TASK_BASIC_INFO_COUNT;
745 kern_return_t result =
746 task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)&info, &count);
747 if (UNLIKELY(result != KERN_SUCCESS)) {
748 Report("Cannot get task info. Error: %d\n", result);
749 Die();
750 }
751 return info.resident_size;
752 }
753
internal_start_thread(void * (* func)(void * arg),void * arg)754 void *internal_start_thread(void *(*func)(void *arg), void *arg) {
755 // Start the thread with signals blocked, otherwise it can steal user signals.
756 __sanitizer_sigset_t set, old;
757 internal_sigfillset(&set);
758 internal_sigprocmask(SIG_SETMASK, &set, &old);
759 pthread_t th;
760 pthread_create(&th, 0, func, arg);
761 internal_sigprocmask(SIG_SETMASK, &old, 0);
762 return th;
763 }
764
internal_join_thread(void * th)765 void internal_join_thread(void *th) { pthread_join((pthread_t)th, 0); }
766
767 #if !SANITIZER_GO
768 static Mutex syslog_lock;
769 # endif
770
WriteOneLineToSyslog(const char * s)771 void WriteOneLineToSyslog(const char *s) {
772 #if !SANITIZER_GO
773 syslog_lock.CheckLocked();
774 if (GetMacosAlignedVersion() >= MacosVersion(10, 12)) {
775 os_log_error(OS_LOG_DEFAULT, "%{public}s", s);
776 } else {
777 asl_log(nullptr, nullptr, ASL_LEVEL_ERR, "%s", s);
778 }
779 #endif
780 }
781
782 // buffer to store crash report application information
783 static char crashreporter_info_buff[__sanitizer::kErrorMessageBufferSize] = {};
784 static Mutex crashreporter_info_mutex;
785
786 extern "C" {
787 // Integrate with crash reporter libraries.
788 #if HAVE_CRASHREPORTERCLIENT_H
789 CRASH_REPORTER_CLIENT_HIDDEN
790 struct crashreporter_annotations_t gCRAnnotations
791 __attribute__((section("__DATA," CRASHREPORTER_ANNOTATIONS_SECTION))) = {
792 CRASHREPORTER_ANNOTATIONS_VERSION,
793 0,
794 0,
795 0,
796 0,
797 0,
798 0,
799 #if CRASHREPORTER_ANNOTATIONS_VERSION > 4
800 0,
801 #endif
802 };
803
804 #else
805 // fall back to old crashreporter api
806 static const char *__crashreporter_info__ __attribute__((__used__)) =
807 &crashreporter_info_buff[0];
808 asm(".desc ___crashreporter_info__, 0x10");
809 #endif
810
811 } // extern "C"
812
CRAppendCrashLogMessage(const char * msg)813 static void CRAppendCrashLogMessage(const char *msg) {
814 Lock l(&crashreporter_info_mutex);
815 internal_strlcat(crashreporter_info_buff, msg,
816 sizeof(crashreporter_info_buff));
817 #if HAVE_CRASHREPORTERCLIENT_H
818 (void)CRSetCrashLogMessage(crashreporter_info_buff);
819 #endif
820 }
821
LogMessageOnPrintf(const char * str)822 void LogMessageOnPrintf(const char *str) {
823 // Log all printf output to CrashLog.
824 if (common_flags()->abort_on_error)
825 CRAppendCrashLogMessage(str);
826 }
827
LogFullErrorReport(const char * buffer)828 void LogFullErrorReport(const char *buffer) {
829 #if !SANITIZER_GO
830 // Log with os_trace. This will make it into the crash log.
831 #if SANITIZER_OS_TRACE
832 if (GetMacosAlignedVersion() >= MacosVersion(10, 10)) {
833 // os_trace requires the message (format parameter) to be a string literal.
834 if (internal_strncmp(SanitizerToolName, "AddressSanitizer",
835 sizeof("AddressSanitizer") - 1) == 0)
836 os_trace("Address Sanitizer reported a failure.");
837 else if (internal_strncmp(SanitizerToolName, "UndefinedBehaviorSanitizer",
838 sizeof("UndefinedBehaviorSanitizer") - 1) == 0)
839 os_trace("Undefined Behavior Sanitizer reported a failure.");
840 else if (internal_strncmp(SanitizerToolName, "ThreadSanitizer",
841 sizeof("ThreadSanitizer") - 1) == 0)
842 os_trace("Thread Sanitizer reported a failure.");
843 else
844 os_trace("Sanitizer tool reported a failure.");
845
846 if (common_flags()->log_to_syslog)
847 os_trace("Consult syslog for more information.");
848 }
849 #endif
850
851 // Log to syslog.
852 // The logging on OS X may call pthread_create so we need the threading
853 // environment to be fully initialized. Also, this should never be called when
854 // holding the thread registry lock since that may result in a deadlock. If
855 // the reporting thread holds the thread registry mutex, and asl_log waits
856 // for GCD to dispatch a new thread, the process will deadlock, because the
857 // pthread_create wrapper needs to acquire the lock as well.
858 Lock l(&syslog_lock);
859 if (common_flags()->log_to_syslog)
860 WriteToSyslog(buffer);
861
862 // The report is added to CrashLog as part of logging all of Printf output.
863 #endif
864 }
865
GetWriteFlag() const866 SignalContext::WriteFlag SignalContext::GetWriteFlag() const {
867 #if defined(__x86_64__) || defined(__i386__)
868 ucontext_t *ucontext = static_cast<ucontext_t*>(context);
869 return ucontext->uc_mcontext->__es.__err & 2 /*T_PF_WRITE*/ ? WRITE : READ;
870 #else
871 return UNKNOWN;
872 #endif
873 }
874
IsTrueFaultingAddress() const875 bool SignalContext::IsTrueFaultingAddress() const {
876 auto si = static_cast<const siginfo_t *>(siginfo);
877 // "Real" SIGSEGV codes (e.g., SEGV_MAPERR, SEGV_MAPERR) are non-zero.
878 return si->si_signo == SIGSEGV && si->si_code != 0;
879 }
880
881 #if defined(__aarch64__) && defined(arm_thread_state64_get_sp)
882 #define AARCH64_GET_REG(r) \
883 (uptr)ptrauth_strip( \
884 (void *)arm_thread_state64_get_##r(ucontext->uc_mcontext->__ss), 0)
885 #else
886 #define AARCH64_GET_REG(r) ucontext->uc_mcontext->__ss.__##r
887 #endif
888
GetPcSpBp(void * context,uptr * pc,uptr * sp,uptr * bp)889 static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
890 ucontext_t *ucontext = (ucontext_t*)context;
891 # if defined(__aarch64__)
892 *pc = AARCH64_GET_REG(pc);
893 # if defined(__IPHONE_8_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_8_0
894 *bp = AARCH64_GET_REG(fp);
895 # else
896 *bp = AARCH64_GET_REG(lr);
897 # endif
898 *sp = AARCH64_GET_REG(sp);
899 # elif defined(__x86_64__)
900 *pc = ucontext->uc_mcontext->__ss.__rip;
901 *bp = ucontext->uc_mcontext->__ss.__rbp;
902 *sp = ucontext->uc_mcontext->__ss.__rsp;
903 # elif defined(__arm__)
904 *pc = ucontext->uc_mcontext->__ss.__pc;
905 *bp = ucontext->uc_mcontext->__ss.__r[7];
906 *sp = ucontext->uc_mcontext->__ss.__sp;
907 # elif defined(__i386__)
908 *pc = ucontext->uc_mcontext->__ss.__eip;
909 *bp = ucontext->uc_mcontext->__ss.__ebp;
910 *sp = ucontext->uc_mcontext->__ss.__esp;
911 # else
912 # error "Unknown architecture"
913 # endif
914 }
915
InitPcSpBp()916 void SignalContext::InitPcSpBp() {
917 addr = (uptr)ptrauth_strip((void *)addr, 0);
918 GetPcSpBp(context, &pc, &sp, &bp);
919 }
920
921 // ASan/TSan use mmap in a way that creates “deallocation gaps” which triggers
922 // EXC_GUARD exceptions on macOS 10.15+ (XNU 19.0+).
DisableMmapExcGuardExceptions()923 static void DisableMmapExcGuardExceptions() {
924 using task_exc_guard_behavior_t = uint32_t;
925 using task_set_exc_guard_behavior_t =
926 kern_return_t(task_t task, task_exc_guard_behavior_t behavior);
927 auto *set_behavior = (task_set_exc_guard_behavior_t *)dlsym(
928 RTLD_DEFAULT, "task_set_exc_guard_behavior");
929 if (set_behavior == nullptr) return;
930 const task_exc_guard_behavior_t task_exc_guard_none = 0;
931 set_behavior(mach_task_self(), task_exc_guard_none);
932 }
933
InitializePlatformEarly()934 void InitializePlatformEarly() {
935 // Only use xnu_fast_mmap when on x86_64 and the kernel supports it.
936 use_xnu_fast_mmap =
937 #if defined(__x86_64__)
938 GetDarwinKernelVersion() >= DarwinKernelVersion(17, 5);
939 #else
940 false;
941 #endif
942 if (GetDarwinKernelVersion() >= DarwinKernelVersion(19, 0))
943 DisableMmapExcGuardExceptions();
944 }
945
946 #if !SANITIZER_GO
947 static const char kDyldInsertLibraries[] = "DYLD_INSERT_LIBRARIES";
948 LowLevelAllocator allocator_for_env;
949
950 // Change the value of the env var |name|, leaking the original value.
951 // If |name_value| is NULL, the variable is deleted from the environment,
952 // otherwise the corresponding "NAME=value" string is replaced with
953 // |name_value|.
LeakyResetEnv(const char * name,const char * name_value)954 void LeakyResetEnv(const char *name, const char *name_value) {
955 char **env = GetEnviron();
956 uptr name_len = internal_strlen(name);
957 while (*env != 0) {
958 uptr len = internal_strlen(*env);
959 if (len > name_len) {
960 const char *p = *env;
961 if (!internal_memcmp(p, name, name_len) && p[name_len] == '=') {
962 // Match.
963 if (name_value) {
964 // Replace the old value with the new one.
965 *env = const_cast<char*>(name_value);
966 } else {
967 // Shift the subsequent pointers back.
968 char **del = env;
969 do {
970 del[0] = del[1];
971 } while (*del++);
972 }
973 }
974 }
975 env++;
976 }
977 }
978
979 SANITIZER_WEAK_CXX_DEFAULT_IMPL
ReexecDisabled()980 bool ReexecDisabled() {
981 return false;
982 }
983
DyldNeedsEnvVariable()984 static bool DyldNeedsEnvVariable() {
985 // If running on OS X 10.11+ or iOS 9.0+, dyld will interpose even if
986 // DYLD_INSERT_LIBRARIES is not set.
987 return GetMacosAlignedVersion() < MacosVersion(10, 11);
988 }
989
MaybeReexec()990 void MaybeReexec() {
991 // FIXME: This should really live in some "InitializePlatform" method.
992 MonotonicNanoTime();
993
994 if (ReexecDisabled()) return;
995
996 // Make sure the dynamic runtime library is preloaded so that the
997 // wrappers work. If it is not, set DYLD_INSERT_LIBRARIES and re-exec
998 // ourselves.
999 Dl_info info;
1000 RAW_CHECK(dladdr((void*)((uptr)&__sanitizer_report_error_summary), &info));
1001 char *dyld_insert_libraries =
1002 const_cast<char*>(GetEnv(kDyldInsertLibraries));
1003 uptr old_env_len = dyld_insert_libraries ?
1004 internal_strlen(dyld_insert_libraries) : 0;
1005 uptr fname_len = internal_strlen(info.dli_fname);
1006 const char *dylib_name = StripModuleName(info.dli_fname);
1007 uptr dylib_name_len = internal_strlen(dylib_name);
1008
1009 bool lib_is_in_env = dyld_insert_libraries &&
1010 internal_strstr(dyld_insert_libraries, dylib_name);
1011 if (DyldNeedsEnvVariable() && !lib_is_in_env) {
1012 // DYLD_INSERT_LIBRARIES is not set or does not contain the runtime
1013 // library.
1014 InternalMmapVector<char> program_name(1024);
1015 uint32_t buf_size = program_name.size();
1016 _NSGetExecutablePath(program_name.data(), &buf_size);
1017 char *new_env = const_cast<char*>(info.dli_fname);
1018 if (dyld_insert_libraries) {
1019 // Append the runtime dylib name to the existing value of
1020 // DYLD_INSERT_LIBRARIES.
1021 new_env = (char*)allocator_for_env.Allocate(old_env_len + fname_len + 2);
1022 internal_strncpy(new_env, dyld_insert_libraries, old_env_len);
1023 new_env[old_env_len] = ':';
1024 // Copy fname_len and add a trailing zero.
1025 internal_strncpy(new_env + old_env_len + 1, info.dli_fname,
1026 fname_len + 1);
1027 // Ok to use setenv() since the wrappers don't depend on the value of
1028 // asan_inited.
1029 setenv(kDyldInsertLibraries, new_env, /*overwrite*/1);
1030 } else {
1031 // Set DYLD_INSERT_LIBRARIES equal to the runtime dylib name.
1032 setenv(kDyldInsertLibraries, info.dli_fname, /*overwrite*/0);
1033 }
1034 VReport(1, "exec()-ing the program with\n");
1035 VReport(1, "%s=%s\n", kDyldInsertLibraries, new_env);
1036 VReport(1, "to enable wrappers.\n");
1037 execv(program_name.data(), *_NSGetArgv());
1038
1039 // We get here only if execv() failed.
1040 Report("ERROR: The process is launched without DYLD_INSERT_LIBRARIES, "
1041 "which is required for the sanitizer to work. We tried to set the "
1042 "environment variable and re-execute itself, but execv() failed, "
1043 "possibly because of sandbox restrictions. Make sure to launch the "
1044 "executable with:\n%s=%s\n", kDyldInsertLibraries, new_env);
1045 RAW_CHECK("execv failed" && 0);
1046 }
1047
1048 // Verify that interceptors really work. We'll use dlsym to locate
1049 // "pthread_create", if interceptors are working, it should really point to
1050 // "wrap_pthread_create" within our own dylib.
1051 Dl_info info_pthread_create;
1052 void *dlopen_addr = dlsym(RTLD_DEFAULT, "pthread_create");
1053 RAW_CHECK(dladdr(dlopen_addr, &info_pthread_create));
1054 if (internal_strcmp(info.dli_fname, info_pthread_create.dli_fname) != 0) {
1055 Report(
1056 "ERROR: Interceptors are not working. This may be because %s is "
1057 "loaded too late (e.g. via dlopen). Please launch the executable "
1058 "with:\n%s=%s\n",
1059 SanitizerToolName, kDyldInsertLibraries, info.dli_fname);
1060 RAW_CHECK("interceptors not installed" && 0);
1061 }
1062
1063 if (!lib_is_in_env)
1064 return;
1065
1066 if (!common_flags()->strip_env)
1067 return;
1068
1069 // DYLD_INSERT_LIBRARIES is set and contains the runtime library. Let's remove
1070 // the dylib from the environment variable, because interceptors are installed
1071 // and we don't want our children to inherit the variable.
1072
1073 uptr env_name_len = internal_strlen(kDyldInsertLibraries);
1074 // Allocate memory to hold the previous env var name, its value, the '='
1075 // sign and the '\0' char.
1076 char *new_env = (char*)allocator_for_env.Allocate(
1077 old_env_len + 2 + env_name_len);
1078 RAW_CHECK(new_env);
1079 internal_memset(new_env, '\0', old_env_len + 2 + env_name_len);
1080 internal_strncpy(new_env, kDyldInsertLibraries, env_name_len);
1081 new_env[env_name_len] = '=';
1082 char *new_env_pos = new_env + env_name_len + 1;
1083
1084 // Iterate over colon-separated pieces of |dyld_insert_libraries|.
1085 char *piece_start = dyld_insert_libraries;
1086 char *piece_end = NULL;
1087 char *old_env_end = dyld_insert_libraries + old_env_len;
1088 do {
1089 if (piece_start[0] == ':') piece_start++;
1090 piece_end = internal_strchr(piece_start, ':');
1091 if (!piece_end) piece_end = dyld_insert_libraries + old_env_len;
1092 if ((uptr)(piece_start - dyld_insert_libraries) > old_env_len) break;
1093 uptr piece_len = piece_end - piece_start;
1094
1095 char *filename_start =
1096 (char *)internal_memrchr(piece_start, '/', piece_len);
1097 uptr filename_len = piece_len;
1098 if (filename_start) {
1099 filename_start += 1;
1100 filename_len = piece_len - (filename_start - piece_start);
1101 } else {
1102 filename_start = piece_start;
1103 }
1104
1105 // If the current piece isn't the runtime library name,
1106 // append it to new_env.
1107 if ((dylib_name_len != filename_len) ||
1108 (internal_memcmp(filename_start, dylib_name, dylib_name_len) != 0)) {
1109 if (new_env_pos != new_env + env_name_len + 1) {
1110 new_env_pos[0] = ':';
1111 new_env_pos++;
1112 }
1113 internal_strncpy(new_env_pos, piece_start, piece_len);
1114 new_env_pos += piece_len;
1115 }
1116 // Move on to the next piece.
1117 piece_start = piece_end;
1118 } while (piece_start < old_env_end);
1119
1120 // Can't use setenv() here, because it requires the allocator to be
1121 // initialized.
1122 // FIXME: instead of filtering DYLD_INSERT_LIBRARIES here, do it in
1123 // a separate function called after InitializeAllocator().
1124 if (new_env_pos == new_env + env_name_len + 1) new_env = NULL;
1125 LeakyResetEnv(kDyldInsertLibraries, new_env);
1126 }
1127 #endif // SANITIZER_GO
1128
GetArgv()1129 char **GetArgv() {
1130 return *_NSGetArgv();
1131 }
1132
1133 #if SANITIZER_IOS && !SANITIZER_IOSSIM
1134 // The task_vm_info struct is normally provided by the macOS SDK, but we need
1135 // fields only available in 10.12+. Declare the struct manually to be able to
1136 // build against older SDKs.
1137 struct __sanitizer_task_vm_info {
1138 mach_vm_size_t virtual_size;
1139 integer_t region_count;
1140 integer_t page_size;
1141 mach_vm_size_t resident_size;
1142 mach_vm_size_t resident_size_peak;
1143 mach_vm_size_t device;
1144 mach_vm_size_t device_peak;
1145 mach_vm_size_t internal;
1146 mach_vm_size_t internal_peak;
1147 mach_vm_size_t external;
1148 mach_vm_size_t external_peak;
1149 mach_vm_size_t reusable;
1150 mach_vm_size_t reusable_peak;
1151 mach_vm_size_t purgeable_volatile_pmap;
1152 mach_vm_size_t purgeable_volatile_resident;
1153 mach_vm_size_t purgeable_volatile_virtual;
1154 mach_vm_size_t compressed;
1155 mach_vm_size_t compressed_peak;
1156 mach_vm_size_t compressed_lifetime;
1157 mach_vm_size_t phys_footprint;
1158 mach_vm_address_t min_address;
1159 mach_vm_address_t max_address;
1160 };
1161 #define __SANITIZER_TASK_VM_INFO_COUNT ((mach_msg_type_number_t) \
1162 (sizeof(__sanitizer_task_vm_info) / sizeof(natural_t)))
1163
GetTaskInfoMaxAddress()1164 static uptr GetTaskInfoMaxAddress() {
1165 __sanitizer_task_vm_info vm_info = {} /* zero initialize */;
1166 mach_msg_type_number_t count = __SANITIZER_TASK_VM_INFO_COUNT;
1167 int err = task_info(mach_task_self(), TASK_VM_INFO, (int *)&vm_info, &count);
1168 return err ? 0 : vm_info.max_address;
1169 }
1170
GetMaxUserVirtualAddress()1171 uptr GetMaxUserVirtualAddress() {
1172 static uptr max_vm = GetTaskInfoMaxAddress();
1173 if (max_vm != 0) {
1174 const uptr ret_value = max_vm - 1;
1175 CHECK_LE(ret_value, SANITIZER_MMAP_RANGE_SIZE);
1176 return ret_value;
1177 }
1178
1179 // xnu cannot provide vm address limit
1180 # if SANITIZER_WORDSIZE == 32
1181 constexpr uptr fallback_max_vm = 0xffe00000 - 1;
1182 # else
1183 constexpr uptr fallback_max_vm = 0x200000000 - 1;
1184 # endif
1185 static_assert(fallback_max_vm <= SANITIZER_MMAP_RANGE_SIZE,
1186 "Max virtual address must be less than mmap range size.");
1187 return fallback_max_vm;
1188 }
1189
1190 #else // !SANITIZER_IOS
1191
GetMaxUserVirtualAddress()1192 uptr GetMaxUserVirtualAddress() {
1193 # if SANITIZER_WORDSIZE == 64
1194 constexpr uptr max_vm = (1ULL << 47) - 1; // 0x00007fffffffffffUL;
1195 # else // SANITIZER_WORDSIZE == 32
1196 static_assert(SANITIZER_WORDSIZE == 32, "Wrong wordsize");
1197 constexpr uptr max_vm = (1ULL << 32) - 1; // 0xffffffff;
1198 # endif
1199 static_assert(max_vm <= SANITIZER_MMAP_RANGE_SIZE,
1200 "Max virtual address must be less than mmap range size.");
1201 return max_vm;
1202 }
1203 #endif
1204
GetMaxVirtualAddress()1205 uptr GetMaxVirtualAddress() {
1206 return GetMaxUserVirtualAddress();
1207 }
1208
MapDynamicShadow(uptr shadow_size_bytes,uptr shadow_scale,uptr min_shadow_base_alignment,uptr & high_mem_end)1209 uptr MapDynamicShadow(uptr shadow_size_bytes, uptr shadow_scale,
1210 uptr min_shadow_base_alignment, uptr &high_mem_end) {
1211 const uptr granularity = GetMmapGranularity();
1212 const uptr alignment =
1213 Max<uptr>(granularity << shadow_scale, 1ULL << min_shadow_base_alignment);
1214 const uptr left_padding =
1215 Max<uptr>(granularity, 1ULL << min_shadow_base_alignment);
1216
1217 uptr space_size = shadow_size_bytes + left_padding;
1218
1219 uptr largest_gap_found = 0;
1220 uptr max_occupied_addr = 0;
1221 VReport(2, "FindDynamicShadowStart, space_size = %p\n", space_size);
1222 uptr shadow_start =
1223 FindAvailableMemoryRange(space_size, alignment, granularity,
1224 &largest_gap_found, &max_occupied_addr);
1225 // If the shadow doesn't fit, restrict the address space to make it fit.
1226 if (shadow_start == 0) {
1227 VReport(
1228 2,
1229 "Shadow doesn't fit, largest_gap_found = %p, max_occupied_addr = %p\n",
1230 largest_gap_found, max_occupied_addr);
1231 uptr new_max_vm = RoundDownTo(largest_gap_found << shadow_scale, alignment);
1232 if (new_max_vm < max_occupied_addr) {
1233 Report("Unable to find a memory range for dynamic shadow.\n");
1234 Report(
1235 "space_size = %p, largest_gap_found = %p, max_occupied_addr = %p, "
1236 "new_max_vm = %p\n",
1237 space_size, largest_gap_found, max_occupied_addr, new_max_vm);
1238 CHECK(0 && "cannot place shadow");
1239 }
1240 RestrictMemoryToMaxAddress(new_max_vm);
1241 high_mem_end = new_max_vm - 1;
1242 space_size = (high_mem_end >> shadow_scale) + left_padding;
1243 VReport(2, "FindDynamicShadowStart, space_size = %p\n", space_size);
1244 shadow_start = FindAvailableMemoryRange(space_size, alignment, granularity,
1245 nullptr, nullptr);
1246 if (shadow_start == 0) {
1247 Report("Unable to find a memory range after restricting VM.\n");
1248 CHECK(0 && "cannot place shadow after restricting vm");
1249 }
1250 }
1251 CHECK_NE((uptr)0, shadow_start);
1252 CHECK(IsAligned(shadow_start, alignment));
1253 return shadow_start;
1254 }
1255
MapDynamicShadowAndAliases(uptr shadow_size,uptr alias_size,uptr num_aliases,uptr ring_buffer_size)1256 uptr MapDynamicShadowAndAliases(uptr shadow_size, uptr alias_size,
1257 uptr num_aliases, uptr ring_buffer_size) {
1258 CHECK(false && "HWASan aliasing is unimplemented on Mac");
1259 return 0;
1260 }
1261
FindAvailableMemoryRange(uptr size,uptr alignment,uptr left_padding,uptr * largest_gap_found,uptr * max_occupied_addr)1262 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
1263 uptr *largest_gap_found,
1264 uptr *max_occupied_addr) {
1265 typedef vm_region_submap_short_info_data_64_t RegionInfo;
1266 enum { kRegionInfoSize = VM_REGION_SUBMAP_SHORT_INFO_COUNT_64 };
1267 // Start searching for available memory region past PAGEZERO, which is
1268 // 4KB on 32-bit and 4GB on 64-bit.
1269 mach_vm_address_t start_address =
1270 (SANITIZER_WORDSIZE == 32) ? 0x000000001000 : 0x000100000000;
1271
1272 mach_vm_address_t address = start_address;
1273 mach_vm_address_t free_begin = start_address;
1274 kern_return_t kr = KERN_SUCCESS;
1275 if (largest_gap_found) *largest_gap_found = 0;
1276 if (max_occupied_addr) *max_occupied_addr = 0;
1277 while (kr == KERN_SUCCESS) {
1278 mach_vm_size_t vmsize = 0;
1279 natural_t depth = 0;
1280 RegionInfo vminfo;
1281 mach_msg_type_number_t count = kRegionInfoSize;
1282 kr = mach_vm_region_recurse(mach_task_self(), &address, &vmsize, &depth,
1283 (vm_region_info_t)&vminfo, &count);
1284 if (kr == KERN_INVALID_ADDRESS) {
1285 // No more regions beyond "address", consider the gap at the end of VM.
1286 address = GetMaxVirtualAddress() + 1;
1287 vmsize = 0;
1288 } else {
1289 if (max_occupied_addr) *max_occupied_addr = address + vmsize;
1290 }
1291 if (free_begin != address) {
1292 // We found a free region [free_begin..address-1].
1293 uptr gap_start = RoundUpTo((uptr)free_begin + left_padding, alignment);
1294 uptr gap_end = RoundDownTo((uptr)address, alignment);
1295 uptr gap_size = gap_end > gap_start ? gap_end - gap_start : 0;
1296 if (size < gap_size) {
1297 return gap_start;
1298 }
1299
1300 if (largest_gap_found && *largest_gap_found < gap_size) {
1301 *largest_gap_found = gap_size;
1302 }
1303 }
1304 // Move to the next region.
1305 address += vmsize;
1306 free_begin = address;
1307 }
1308
1309 // We looked at all free regions and could not find one large enough.
1310 return 0;
1311 }
1312
1313 // FIXME implement on this platform.
GetMemoryProfile(fill_profile_f cb,uptr * stats,uptr stats_size)1314 void GetMemoryProfile(fill_profile_f cb, uptr *stats, uptr stats_size) { }
1315
DumpAllRegisters(void * context)1316 void SignalContext::DumpAllRegisters(void *context) {
1317 Report("Register values:\n");
1318
1319 ucontext_t *ucontext = (ucontext_t*)context;
1320 # define DUMPREG64(r) \
1321 Printf("%s = 0x%016llx ", #r, ucontext->uc_mcontext->__ss.__ ## r);
1322 # define DUMPREGA64(r) \
1323 Printf(" %s = 0x%016llx ", #r, AARCH64_GET_REG(r));
1324 # define DUMPREG32(r) \
1325 Printf("%s = 0x%08x ", #r, ucontext->uc_mcontext->__ss.__ ## r);
1326 # define DUMPREG_(r) Printf(" "); DUMPREG(r);
1327 # define DUMPREG__(r) Printf(" "); DUMPREG(r);
1328 # define DUMPREG___(r) Printf(" "); DUMPREG(r);
1329
1330 # if defined(__x86_64__)
1331 # define DUMPREG(r) DUMPREG64(r)
1332 DUMPREG(rax); DUMPREG(rbx); DUMPREG(rcx); DUMPREG(rdx); Printf("\n");
1333 DUMPREG(rdi); DUMPREG(rsi); DUMPREG(rbp); DUMPREG(rsp); Printf("\n");
1334 DUMPREG_(r8); DUMPREG_(r9); DUMPREG(r10); DUMPREG(r11); Printf("\n");
1335 DUMPREG(r12); DUMPREG(r13); DUMPREG(r14); DUMPREG(r15); Printf("\n");
1336 # elif defined(__i386__)
1337 # define DUMPREG(r) DUMPREG32(r)
1338 DUMPREG(eax); DUMPREG(ebx); DUMPREG(ecx); DUMPREG(edx); Printf("\n");
1339 DUMPREG(edi); DUMPREG(esi); DUMPREG(ebp); DUMPREG(esp); Printf("\n");
1340 # elif defined(__aarch64__)
1341 # define DUMPREG(r) DUMPREG64(r)
1342 DUMPREG_(x[0]); DUMPREG_(x[1]); DUMPREG_(x[2]); DUMPREG_(x[3]); Printf("\n");
1343 DUMPREG_(x[4]); DUMPREG_(x[5]); DUMPREG_(x[6]); DUMPREG_(x[7]); Printf("\n");
1344 DUMPREG_(x[8]); DUMPREG_(x[9]); DUMPREG(x[10]); DUMPREG(x[11]); Printf("\n");
1345 DUMPREG(x[12]); DUMPREG(x[13]); DUMPREG(x[14]); DUMPREG(x[15]); Printf("\n");
1346 DUMPREG(x[16]); DUMPREG(x[17]); DUMPREG(x[18]); DUMPREG(x[19]); Printf("\n");
1347 DUMPREG(x[20]); DUMPREG(x[21]); DUMPREG(x[22]); DUMPREG(x[23]); Printf("\n");
1348 DUMPREG(x[24]); DUMPREG(x[25]); DUMPREG(x[26]); DUMPREG(x[27]); Printf("\n");
1349 DUMPREG(x[28]); DUMPREGA64(fp); DUMPREGA64(lr); DUMPREGA64(sp); Printf("\n");
1350 # elif defined(__arm__)
1351 # define DUMPREG(r) DUMPREG32(r)
1352 DUMPREG_(r[0]); DUMPREG_(r[1]); DUMPREG_(r[2]); DUMPREG_(r[3]); Printf("\n");
1353 DUMPREG_(r[4]); DUMPREG_(r[5]); DUMPREG_(r[6]); DUMPREG_(r[7]); Printf("\n");
1354 DUMPREG_(r[8]); DUMPREG_(r[9]); DUMPREG(r[10]); DUMPREG(r[11]); Printf("\n");
1355 DUMPREG(r[12]); DUMPREG___(sp); DUMPREG___(lr); DUMPREG___(pc); Printf("\n");
1356 # else
1357 # error "Unknown architecture"
1358 # endif
1359
1360 # undef DUMPREG64
1361 # undef DUMPREG32
1362 # undef DUMPREG_
1363 # undef DUMPREG__
1364 # undef DUMPREG___
1365 # undef DUMPREG
1366 }
1367
CompareBaseAddress(const LoadedModule & a,const LoadedModule & b)1368 static inline bool CompareBaseAddress(const LoadedModule &a,
1369 const LoadedModule &b) {
1370 return a.base_address() < b.base_address();
1371 }
1372
FormatUUID(char * out,uptr size,const u8 * uuid)1373 void FormatUUID(char *out, uptr size, const u8 *uuid) {
1374 internal_snprintf(out, size,
1375 "<%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-"
1376 "%02X%02X%02X%02X%02X%02X>",
1377 uuid[0], uuid[1], uuid[2], uuid[3], uuid[4], uuid[5],
1378 uuid[6], uuid[7], uuid[8], uuid[9], uuid[10], uuid[11],
1379 uuid[12], uuid[13], uuid[14], uuid[15]);
1380 }
1381
DumpProcessMap()1382 void DumpProcessMap() {
1383 Printf("Process module map:\n");
1384 MemoryMappingLayout memory_mapping(false);
1385 InternalMmapVector<LoadedModule> modules;
1386 modules.reserve(128);
1387 memory_mapping.DumpListOfModules(&modules);
1388 Sort(modules.data(), modules.size(), CompareBaseAddress);
1389 for (uptr i = 0; i < modules.size(); ++i) {
1390 char uuid_str[128];
1391 FormatUUID(uuid_str, sizeof(uuid_str), modules[i].uuid());
1392 Printf("0x%zx-0x%zx %s (%s) %s\n", modules[i].base_address(),
1393 modules[i].max_executable_address(), modules[i].full_name(),
1394 ModuleArchToString(modules[i].arch()), uuid_str);
1395 }
1396 Printf("End of module map.\n");
1397 }
1398
CheckNoDeepBind(const char * filename,int flag)1399 void CheckNoDeepBind(const char *filename, int flag) {
1400 // Do nothing.
1401 }
1402
GetRandom(void * buffer,uptr length,bool blocking)1403 bool GetRandom(void *buffer, uptr length, bool blocking) {
1404 if (!buffer || !length || length > 256)
1405 return false;
1406 // arc4random never fails.
1407 REAL(arc4random_buf)(buffer, length);
1408 return true;
1409 }
1410
GetNumberOfCPUs()1411 u32 GetNumberOfCPUs() {
1412 return (u32)sysconf(_SC_NPROCESSORS_ONLN);
1413 }
1414
InitializePlatformCommonFlags(CommonFlags * cf)1415 void InitializePlatformCommonFlags(CommonFlags *cf) {}
1416
1417 } // namespace __sanitizer
1418
1419 #endif // SANITIZER_MAC
1420