src/compiler-rt/lib/sanitizer_common/sanitizer_mac.cc

   1 //===-- sanitizer_mac.cc --------------------------------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file is shared between various sanitizers' runtime libraries and
  11 // implements OSX-specific functions.
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "sanitizer_platform.h"
  15 #if SANITIZER_MAC
  16 #include "sanitizer_mac.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_flags.h"
  27 #include "sanitizer_internal_defs.h"
  28 #include "sanitizer_libc.h"
  29 #include "sanitizer_placement_new.h"
  30 #include "sanitizer_platform_limits_posix.h"
  31 #include "sanitizer_procmaps.h"
  32
  33 #if !SANITIZER_IOS
  34 #include <crt_externs.h>  // for _NSGetEnviron
  35 #else
  36 extern char **environ;
  37 #endif
  38
  39 #if defined(__has_include) && __has_include(<os/trace.h>)
  40 #define SANITIZER_OS_TRACE 1
  41 #include <os/trace.h>
  42 #else
  43 #define SANITIZER_OS_TRACE 0
  44 #endif
  45
  46 #if !SANITIZER_IOS
  47 #include <crt_externs.h>  // for _NSGetArgv and _NSGetEnviron
  48 #else
  49 extern "C" {
  50   extern char ***_NSGetArgv(void);
  51 }
  52 #endif
  53
  54 #include <asl.h>
  55 #include <dlfcn.h>  // for dladdr()
  56 #include <errno.h>
  57 #include <fcntl.h>
  58 #include <libkern/OSAtomic.h>
  59 #include <mach-o/dyld.h>
  60 #include <mach/mach.h>
  61 #include <mach/vm_statistics.h>
  62 #include <pthread.h>
  63 #include <sched.h>
  64 #include <signal.h>
  65 #include <stdlib.h>
  66 #include <sys/mman.h>
  67 #include <sys/resource.h>
  68 #include <sys/stat.h>
  69 #include <sys/sysctl.h>
  70 #include <sys/types.h>
  71 #include <sys/wait.h>
  72 #include <unistd.h>
  73 #include <util.h>
  74
  75 // From <crt_externs.h>, but we don't have that file on iOS.
  76 extern "C" {
  77   extern char ***_NSGetArgv(void);
  78   extern char ***_NSGetEnviron(void);
  79 }
  80
  81 // From <mach/mach_vm.h>, but we don't have that file on iOS.
  82 extern "C" {
  83   extern kern_return_t mach_vm_region_recurse(
  84     vm_map_t target_task,
  85     mach_vm_address_t *address,
  86     mach_vm_size_t *size,
  87     natural_t *nesting_depth,
  88     vm_region_recurse_info_t info,
  89     mach_msg_type_number_t *infoCnt);
  90 }
  91
  92 namespace __sanitizer {
  93
  94 #include "sanitizer_syscall_generic.inc"
  95
  96 // Direct syscalls, don't call libmalloc hooks.
  97 extern "C" void *__mmap(void *addr, size_t len, int prot, int flags, int fildes,
  98                         off_t off);
  99 extern "C" int __munmap(void *, size_t);
 100
 101 // ---------------------- sanitizer_libc.h
 102 uptr internal_mmap(void *addr, size_t length, int prot, int flags,
 103                    int fd, u64 offset) {
 104   if (fd == -1) fd = VM_MAKE_TAG(VM_MEMORY_ANALYSIS_TOOL);
 105   return (uptr)__mmap(addr, length, prot, flags, fd, offset);
 106 }
 107
 108 uptr internal_munmap(void *addr, uptr length) {
 109   return __munmap(addr, length);
 110 }
 111
 112 int internal_mprotect(void *addr, uptr length, int prot) {
 113   return mprotect(addr, length, prot);
 114 }
 115
 116 uptr internal_close(fd_t fd) {
 117   return close(fd);
 118 }
 119
 120 uptr internal_open(const char *filename, int flags) {
 121   return open(filename, flags);
 122 }
 123
 124 uptr internal_open(const char *filename, int flags, u32 mode) {
 125   return open(filename, flags, mode);
 126 }
 127
 128 uptr internal_read(fd_t fd, void *buf, uptr count) {
 129   return read(fd, buf, count);
 130 }
 131
 132 uptr internal_write(fd_t fd, const void *buf, uptr count) {
 133   return write(fd, buf, count);
 134 }
 135
 136 uptr internal_stat(const char *path, void *buf) {
 137   return stat(path, (struct stat *)buf);
 138 }
 139
 140 uptr internal_lstat(const char *path, void *buf) {
 141   return lstat(path, (struct stat *)buf);
 142 }
 143
 144 uptr internal_fstat(fd_t fd, void *buf) {
 145   return fstat(fd, (struct stat *)buf);
 146 }
 147
 148 uptr internal_filesize(fd_t fd) {
 149   struct stat st;
 150   if (internal_fstat(fd, &st))
 151     return -1;
 152   return (uptr)st.st_size;
 153 }
 154
 155 uptr internal_dup2(int oldfd, int newfd) {
 156   return dup2(oldfd, newfd);
 157 }
 158
 159 uptr internal_readlink(const char *path, char *buf, uptr bufsize) {
 160   return readlink(path, buf, bufsize);
 161 }
 162
 163 uptr internal_unlink(const char *path) {
 164   return unlink(path);
 165 }
 166
 167 uptr internal_sched_yield() {
 168   return sched_yield();
 169 }
 170
 171 void internal__exit(int exitcode) {
 172   _exit(exitcode);
 173 }
 174
 175 unsigned int internal_sleep(unsigned int seconds) {
 176   return sleep(seconds);
 177 }
 178
 179 uptr internal_getpid() {
 180   return getpid();
 181 }
 182
 183 int internal_sigaction(int signum, const void *act, void *oldact) {
 184   return sigaction(signum,
 185                    (struct sigaction *)act, (struct sigaction *)oldact);
 186 }
 187
 188 void internal_sigfillset(__sanitizer_sigset_t *set) { sigfillset(set); }
 189
 190 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
 191                           __sanitizer_sigset_t *oldset) {
 192   return sigprocmask(how, set, oldset);
 193 }
 194
 195 // Doesn't call pthread_atfork() handlers.
 196 extern "C" pid_t __fork(void);
 197
 198 int internal_fork() {
 199   return __fork();
 200 }
 201
 202 int internal_forkpty(int *amaster) {
 203   int master, slave;
 204   if (openpty(&master, &slave, nullptr, nullptr, nullptr) == -1) return -1;
 205   int pid = __fork();
 206   if (pid == -1) {
 207     close(master);
 208     close(slave);
 209     return -1;
 210   }
 211   if (pid == 0) {
 212     close(master);
 213     if (login_tty(slave) != 0) {
 214       // We already forked, there's not much we can do.  Let's quit.
 215       Report("login_tty failed (errno %d)\n", errno);
 216       internal__exit(1);
 217     }
 218   } else {
 219     *amaster = master;
 220     close(slave);
 221   }
 222   return pid;
 223 }
 224
 225 uptr internal_rename(const char *oldpath, const char *newpath) {
 226   return rename(oldpath, newpath);
 227 }
 228
 229 uptr internal_ftruncate(fd_t fd, uptr size) {
 230   return ftruncate(fd, size);
 231 }
 232
 233 uptr internal_execve(const char *filename, char *const argv[],
 234                      char *const envp[]) {
 235   return execve(filename, argv, envp);
 236 }
 237
 238 uptr internal_waitpid(int pid, int *status, int options) {
 239   return waitpid(pid, status, options);
 240 }
 241
 242 // ----------------- sanitizer_common.h
 243 bool FileExists(const char *filename) {
 244   struct stat st;
 245   if (stat(filename, &st))
 246     return false;
 247   // Sanity check: filename is a regular file.
 248   return S_ISREG(st.st_mode);
 249 }
 250
 251 uptr GetTid() {
 252   // FIXME: This can potentially get truncated on 32-bit, where uptr is 4 bytes.
 253   uint64_t tid;
 254   pthread_threadid_np(nullptr, &tid);
 255   return tid;
 256 }
 257
 258 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
 259                                 uptr *stack_bottom) {
 260   CHECK(stack_top);
 261   CHECK(stack_bottom);
 262   uptr stacksize = pthread_get_stacksize_np(pthread_self());
 263   // pthread_get_stacksize_np() returns an incorrect stack size for the main
 264   // thread on Mavericks. See
 265   // https://github.com/google/sanitizers/issues/261
 266   if ((GetMacosVersion() >= MACOS_VERSION_MAVERICKS) && at_initialization &&
 267       stacksize == (1 << 19))  {
 268     struct rlimit rl;
 269     CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
 270     // Most often rl.rlim_cur will be the desired 8M.
 271     if (rl.rlim_cur < kMaxThreadStackSize) {
 272       stacksize = rl.rlim_cur;
 273     } else {
 274       stacksize = kMaxThreadStackSize;
 275     }
 276   }
 277   void *stackaddr = pthread_get_stackaddr_np(pthread_self());
 278   *stack_top = (uptr)stackaddr;
 279   *stack_bottom = *stack_top - stacksize;
 280 }
 281
 282 char **GetEnviron() {
 283 #if !SANITIZER_IOS
 284   char ***env_ptr = _NSGetEnviron();
 285   if (!env_ptr) {
 286     Report("_NSGetEnviron() returned NULL. Please make sure __asan_init() is "
 287            "called after libSystem_initializer().\n");
 288     CHECK(env_ptr);
 289   }
 290   char **environ = *env_ptr;
 291 #endif
 292   CHECK(environ);
 293   return environ;
 294 }
 295
 296 const char *GetEnv(const char *name) {
 297   char **env = GetEnviron();
 298   uptr name_len = internal_strlen(name);
 299   while (*env != 0) {
 300     uptr len = internal_strlen(*env);
 301     if (len > name_len) {
 302       const char *p = *env;
 303       if (!internal_memcmp(p, name, name_len) &&
 304           p[name_len] == '=') {  // Match.
 305         return *env + name_len + 1;  // String starting after =.
 306       }
 307     }
 308     env++;
 309   }
 310   return 0;
 311 }
 312
 313 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
 314   CHECK_LE(kMaxPathLength, buf_len);
 315
 316   // On OS X the executable path is saved to the stack by dyld. Reading it
 317   // from there is much faster than calling dladdr, especially for large
 318   // binaries with symbols.
 319   InternalScopedString exe_path(kMaxPathLength);
 320   uint32_t size = exe_path.size();
 321   if (_NSGetExecutablePath(exe_path.data(), &size) == 0 &&
 322       realpath(exe_path.data(), buf) != 0) {
 323     return internal_strlen(buf);
 324   }
 325   return 0;
 326 }
 327
 328 uptr ReadLongProcessName(/*out*/char *buf, uptr buf_len) {
 329   return ReadBinaryName(buf, buf_len);
 330 }
 331
 332 void ReExec() {
 333   UNIMPLEMENTED();
 334 }
 335
 336 uptr GetPageSize() {
 337   return sysconf(_SC_PAGESIZE);
 338 }
 339
 340 BlockingMutex::BlockingMutex() {
 341   internal_memset(this, 0, sizeof(*this));
 342 }
 343
 344 void BlockingMutex::Lock() {
 345   CHECK(sizeof(OSSpinLock) <= sizeof(opaque_storage_));
 346   CHECK_EQ(OS_SPINLOCK_INIT, 0);
 347   CHECK_NE(owner_, (uptr)pthread_self());
 348   OSSpinLockLock((OSSpinLock*)&opaque_storage_);
 349   CHECK(!owner_);
 350   owner_ = (uptr)pthread_self();
 351 }
 352
 353 void BlockingMutex::Unlock() {
 354   CHECK(owner_ == (uptr)pthread_self());
 355   owner_ = 0;
 356   OSSpinLockUnlock((OSSpinLock*)&opaque_storage_);
 357 }
 358
 359 void BlockingMutex::CheckLocked() {
 360   CHECK_EQ((uptr)pthread_self(), owner_);
 361 }
 362
 363 u64 NanoTime() {
 364   return 0;
 365 }
 366
 367 uptr GetTlsSize() {
 368   return 0;
 369 }
 370
 371 void InitTlsSize() {
 372 }
 373
 374 void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
 375                           uptr *tls_addr, uptr *tls_size) {
 376 #if !SANITIZER_GO
 377   uptr stack_top, stack_bottom;
 378   GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
 379   *stk_addr = stack_bottom;
 380   *stk_size = stack_top - stack_bottom;
 381   *tls_addr = 0;
 382   *tls_size = 0;
 383 #else
 384   *stk_addr = 0;
 385   *stk_size = 0;
 386   *tls_addr = 0;
 387   *tls_size = 0;
 388 #endif
 389 }
 390
 391 void ListOfModules::init() {
 392   clear();
 393   MemoryMappingLayout memory_mapping(false);
 394   memory_mapping.DumpListOfModules(&modules_);
 395 }
 396
 397 bool IsHandledDeadlySignal(int signum) {
 398   if ((SANITIZER_WATCHOS || SANITIZER_TVOS) && !(SANITIZER_IOSSIM))
 399     // Handling fatal signals on watchOS and tvOS devices is disallowed.
 400     return false;
 401   if (common_flags()->handle_abort && signum == SIGABRT)
 402     return true;
 403   if (common_flags()->handle_sigill && signum == SIGILL)
 404     return true;
 405   return (signum == SIGSEGV || signum == SIGBUS) && common_flags()->handle_segv;
 406 }
 407
 408 MacosVersion cached_macos_version = MACOS_VERSION_UNINITIALIZED;
 409
 410 MacosVersion GetMacosVersionInternal() {
 411   int mib[2] = { CTL_KERN, KERN_OSRELEASE };
 412   char version[100];
 413   uptr len = 0, maxlen = sizeof(version) / sizeof(version[0]);
 414   for (uptr i = 0; i < maxlen; i++) version[i] = '\0';
 415   // Get the version length.
 416   CHECK_NE(sysctl(mib, 2, 0, &len, 0, 0), -1);
 417   CHECK_LT(len, maxlen);
 418   CHECK_NE(sysctl(mib, 2, version, &len, 0, 0), -1);
 419   switch (version[0]) {
 420     case '9': return MACOS_VERSION_LEOPARD;
 421     case '1': {
 422       switch (version[1]) {
 423         case '0': return MACOS_VERSION_SNOW_LEOPARD;
 424         case '1': return MACOS_VERSION_LION;
 425         case '2': return MACOS_VERSION_MOUNTAIN_LION;
 426         case '3': return MACOS_VERSION_MAVERICKS;
 427         case '4': return MACOS_VERSION_YOSEMITE;
 428         default:
 429           if (IsDigit(version[1]))
 430             return MACOS_VERSION_UNKNOWN_NEWER;
 431           else
 432             return MACOS_VERSION_UNKNOWN;
 433       }
 434     }
 435     default: return MACOS_VERSION_UNKNOWN;
 436   }
 437 }
 438
 439 MacosVersion GetMacosVersion() {
 440   atomic_uint32_t *cache =
 441       reinterpret_cast<atomic_uint32_t*>(&cached_macos_version);
 442   MacosVersion result =
 443       static_cast<MacosVersion>(atomic_load(cache, memory_order_acquire));
 444   if (result == MACOS_VERSION_UNINITIALIZED) {
 445     result = GetMacosVersionInternal();
 446     atomic_store(cache, result, memory_order_release);
 447   }
 448   return result;
 449 }
 450
 451 bool PlatformHasDifferentMemcpyAndMemmove() {
 452   // On OS X 10.7 memcpy() and memmove() are both resolved
 453   // into memmove$VARIANT$sse42.
 454   // See also https://github.com/google/sanitizers/issues/34.
 455   // TODO(glider): need to check dynamically that memcpy() and memmove() are
 456   // actually the same function.
 457   return GetMacosVersion() == MACOS_VERSION_SNOW_LEOPARD;
 458 }
 459
 460 uptr GetRSS() {
 461   struct task_basic_info info;
 462   unsigned count = TASK_BASIC_INFO_COUNT;
 463   kern_return_t result =
 464       task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)&info, &count);
 465   if (UNLIKELY(result != KERN_SUCCESS)) {
 466     Report("Cannot get task info. Error: %d\n", result);
 467     Die();
 468   }
 469   return info.resident_size;
 470 }
 471
 472 void *internal_start_thread(void(*func)(void *arg), void *arg) {
 473   // Start the thread with signals blocked, otherwise it can steal user signals.
 474   __sanitizer_sigset_t set, old;
 475   internal_sigfillset(&set);
 476   internal_sigprocmask(SIG_SETMASK, &set, &old);
 477   pthread_t th;
 478   pthread_create(&th, 0, (void*(*)(void *arg))func, arg);
 479   internal_sigprocmask(SIG_SETMASK, &old, 0);
 480   return th;
 481 }
 482
 483 void internal_join_thread(void *th) { pthread_join((pthread_t)th, 0); }
 484
 485 #if !SANITIZER_GO
 486 static BlockingMutex syslog_lock(LINKER_INITIALIZED);
 487 #endif
 488
 489 void WriteOneLineToSyslog(const char *s) {
 490 #if !SANITIZER_GO
 491   syslog_lock.CheckLocked();
 492   asl_log(nullptr, nullptr, ASL_LEVEL_ERR, "%s", s);
 493 #endif
 494 }
 495
 496 void LogMessageOnPrintf(const char *str) {
 497   // Log all printf output to CrashLog.
 498   if (common_flags()->abort_on_error)
 499     CRAppendCrashLogMessage(str);
 500 }
 501
 502 void LogFullErrorReport(const char *buffer) {
 503 #if !SANITIZER_GO
 504   // Log with os_trace. This will make it into the crash log.
 505 #if SANITIZER_OS_TRACE
 506   if (GetMacosVersion() >= MACOS_VERSION_YOSEMITE) {
 507     // os_trace requires the message (format parameter) to be a string literal.
 508     if (internal_strncmp(SanitizerToolName, "AddressSanitizer",
 509                          sizeof("AddressSanitizer") - 1) == 0)
 510       os_trace("Address Sanitizer reported a failure.");
 511     else if (internal_strncmp(SanitizerToolName, "UndefinedBehaviorSanitizer",
 512                               sizeof("UndefinedBehaviorSanitizer") - 1) == 0)
 513       os_trace("Undefined Behavior Sanitizer reported a failure.");
 514     else if (internal_strncmp(SanitizerToolName, "ThreadSanitizer",
 515                               sizeof("ThreadSanitizer") - 1) == 0)
 516       os_trace("Thread Sanitizer reported a failure.");
 517     else
 518       os_trace("Sanitizer tool reported a failure.");
 519
 520     if (common_flags()->log_to_syslog)
 521       os_trace("Consult syslog for more information.");
 522   }
 523 #endif
 524
 525   // Log to syslog.
 526   // The logging on OS X may call pthread_create so we need the threading
 527   // environment to be fully initialized. Also, this should never be called when
 528   // holding the thread registry lock since that may result in a deadlock. If
 529   // the reporting thread holds the thread registry mutex, and asl_log waits
 530   // for GCD to dispatch a new thread, the process will deadlock, because the
 531   // pthread_create wrapper needs to acquire the lock as well.
 532   BlockingMutexLock l(&syslog_lock);
 533   if (common_flags()->log_to_syslog)
 534     WriteToSyslog(buffer);
 535
 536   // The report is added to CrashLog as part of logging all of Printf output.
 537 #endif
 538 }
 539
 540 SignalContext::WriteFlag SignalContext::GetWriteFlag(void *context) {
 541 #if defined(__x86_64__) || defined(__i386__)
 542   ucontext_t *ucontext = static_cast<ucontext_t*>(context);
 543   return ucontext->uc_mcontext->__es.__err & 2 /*T_PF_WRITE*/ ? WRITE : READ;
 544 #else
 545   return UNKNOWN;
 546 #endif
 547 }
 548
 549 void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
 550   ucontext_t *ucontext = (ucontext_t*)context;
 551 # if defined(__aarch64__)
 552   *pc = ucontext->uc_mcontext->__ss.__pc;
 553 #   if defined(__IPHONE_8_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_8_0
 554   *bp = ucontext->uc_mcontext->__ss.__fp;
 555 #   else
 556   *bp = ucontext->uc_mcontext->__ss.__lr;
 557 #   endif
 558   *sp = ucontext->uc_mcontext->__ss.__sp;
 559 # elif defined(__x86_64__)
 560   *pc = ucontext->uc_mcontext->__ss.__rip;
 561   *bp = ucontext->uc_mcontext->__ss.__rbp;
 562   *sp = ucontext->uc_mcontext->__ss.__rsp;
 563 # elif defined(__arm__)
 564   *pc = ucontext->uc_mcontext->__ss.__pc;
 565   *bp = ucontext->uc_mcontext->__ss.__r[7];
 566   *sp = ucontext->uc_mcontext->__ss.__sp;
 567 # elif defined(__i386__)
 568   *pc = ucontext->uc_mcontext->__ss.__eip;
 569   *bp = ucontext->uc_mcontext->__ss.__ebp;
 570   *sp = ucontext->uc_mcontext->__ss.__esp;
 571 # else
 572 # error "Unknown architecture"
 573 # endif
 574 }
 575
 576 #if !SANITIZER_GO
 577 static const char kDyldInsertLibraries[] = "DYLD_INSERT_LIBRARIES";
 578 LowLevelAllocator allocator_for_env;
 579
 580 // Change the value of the env var |name|, leaking the original value.
 581 // If |name_value| is NULL, the variable is deleted from the environment,
 582 // otherwise the corresponding "NAME=value" string is replaced with
 583 // |name_value|.
 584 void LeakyResetEnv(const char *name, const char *name_value) {
 585   char **env = GetEnviron();
 586   uptr name_len = internal_strlen(name);
 587   while (*env != 0) {
 588     uptr len = internal_strlen(*env);
 589     if (len > name_len) {
 590       const char *p = *env;
 591       if (!internal_memcmp(p, name, name_len) && p[name_len] == '=') {
 592         // Match.
 593         if (name_value) {
 594           // Replace the old value with the new one.
 595           *env = const_cast<char*>(name_value);
 596         } else {
 597           // Shift the subsequent pointers back.
 598           char **del = env;
 599           do {
 600             del[0] = del[1];
 601           } while (*del++);
 602         }
 603       }
 604     }
 605     env++;
 606   }
 607 }
 608
 609 SANITIZER_WEAK_CXX_DEFAULT_IMPL
 610 bool ReexecDisabled() {
 611   return false;
 612 }
 613
 614 extern "C" SANITIZER_WEAK_ATTRIBUTE double dyldVersionNumber;
 615 static const double kMinDyldVersionWithAutoInterposition = 360.0;
 616
 617 bool DyldNeedsEnvVariable() {
 618   // Although sanitizer support was added to LLVM on OS X 10.7+, GCC users
 619   // still may want use them on older systems. On older Darwin platforms, dyld
 620   // doesn't export dyldVersionNumber symbol and we simply return true.
 621   if (!&dyldVersionNumber) return true;
 622   // If running on OS X 10.11+ or iOS 9.0+, dyld will interpose even if
 623   // DYLD_INSERT_LIBRARIES is not set. However, checking OS version via
 624   // GetMacosVersion() doesn't work for the simulator. Let's instead check
 625   // `dyldVersionNumber`, which is exported by dyld, against a known version
 626   // number from the first OS release where this appeared.
 627   return dyldVersionNumber < kMinDyldVersionWithAutoInterposition;
 628 }
 629
 630 void MaybeReexec() {
 631   if (ReexecDisabled()) return;
 632
 633   // Make sure the dynamic runtime library is preloaded so that the
 634   // wrappers work. If it is not, set DYLD_INSERT_LIBRARIES and re-exec
 635   // ourselves.
 636   Dl_info info;
 637   RAW_CHECK(dladdr((void*)((uptr)&__sanitizer_report_error_summary), &info));
 638   char *dyld_insert_libraries =
 639       const_cast<char*>(GetEnv(kDyldInsertLibraries));
 640   uptr old_env_len = dyld_insert_libraries ?
 641       internal_strlen(dyld_insert_libraries) : 0;
 642   uptr fname_len = internal_strlen(info.dli_fname);
 643   const char *dylib_name = StripModuleName(info.dli_fname);
 644   uptr dylib_name_len = internal_strlen(dylib_name);
 645
 646   bool lib_is_in_env = dyld_insert_libraries &&
 647                        internal_strstr(dyld_insert_libraries, dylib_name);
 648   if (DyldNeedsEnvVariable() && !lib_is_in_env) {
 649     // DYLD_INSERT_LIBRARIES is not set or does not contain the runtime
 650     // library.
 651     InternalScopedString program_name(1024);
 652     uint32_t buf_size = program_name.size();
 653     _NSGetExecutablePath(program_name.data(), &buf_size);
 654     char *new_env = const_cast<char*>(info.dli_fname);
 655     if (dyld_insert_libraries) {
 656       // Append the runtime dylib name to the existing value of
 657       // DYLD_INSERT_LIBRARIES.
 658       new_env = (char*)allocator_for_env.Allocate(old_env_len + fname_len + 2);
 659       internal_strncpy(new_env, dyld_insert_libraries, old_env_len);
 660       new_env[old_env_len] = ':';
 661       // Copy fname_len and add a trailing zero.
 662       internal_strncpy(new_env + old_env_len + 1, info.dli_fname,
 663                        fname_len + 1);
 664       // Ok to use setenv() since the wrappers don't depend on the value of
 665       // asan_inited.
 666       setenv(kDyldInsertLibraries, new_env, /*overwrite*/1);
 667     } else {
 668       // Set DYLD_INSERT_LIBRARIES equal to the runtime dylib name.
 669       setenv(kDyldInsertLibraries, info.dli_fname, /*overwrite*/0);
 670     }
 671     VReport(1, "exec()-ing the program with\n");
 672     VReport(1, "%s=%s\n", kDyldInsertLibraries, new_env);
 673     VReport(1, "to enable wrappers.\n");
 674     execv(program_name.data(), *_NSGetArgv());
 675
 676     // We get here only if execv() failed.
 677     Report("ERROR: The process is launched without DYLD_INSERT_LIBRARIES, "
 678            "which is required for the sanitizer to work. We tried to set the "
 679            "environment variable and re-execute itself, but execv() failed, "
 680            "possibly because of sandbox restrictions. Make sure to launch the "
 681            "executable with:\n%s=%s\n", kDyldInsertLibraries, new_env);
 682     RAW_CHECK("execv failed" && 0);
 683   }
 684
 685   // Verify that interceptors really work.  We'll use dlsym to locate
 686   // "pthread_create", if interceptors are working, it should really point to
 687   // "wrap_pthread_create" within our own dylib.
 688   Dl_info info_pthread_create;
 689   void *dlopen_addr = dlsym(RTLD_DEFAULT, "pthread_create");
 690   RAW_CHECK(dladdr(dlopen_addr, &info_pthread_create));
 691   if (internal_strcmp(info.dli_fname, info_pthread_create.dli_fname) != 0) {
 692     Report(
 693         "ERROR: Interceptors are not working. This may be because %s is "
 694         "loaded too late (e.g. via dlopen). Please launch the executable "
 695         "with:\n%s=%s\n",
 696         SanitizerToolName, kDyldInsertLibraries, info.dli_fname);
 697     RAW_CHECK("interceptors not installed" && 0);
 698   }
 699
 700   if (!lib_is_in_env)
 701     return;
 702
 703   // DYLD_INSERT_LIBRARIES is set and contains the runtime library. Let's remove
 704   // the dylib from the environment variable, because interceptors are installed
 705   // and we don't want our children to inherit the variable.
 706
 707   uptr env_name_len = internal_strlen(kDyldInsertLibraries);
 708   // Allocate memory to hold the previous env var name, its value, the '='
 709   // sign and the '\0' char.
 710   char *new_env = (char*)allocator_for_env.Allocate(
 711       old_env_len + 2 + env_name_len);
 712   RAW_CHECK(new_env);
 713   internal_memset(new_env, '\0', old_env_len + 2 + env_name_len);
 714   internal_strncpy(new_env, kDyldInsertLibraries, env_name_len);
 715   new_env[env_name_len] = '=';
 716   char *new_env_pos = new_env + env_name_len + 1;
 717
 718   // Iterate over colon-separated pieces of |dyld_insert_libraries|.
 719   char *piece_start = dyld_insert_libraries;
 720   char *piece_end = NULL;
 721   char *old_env_end = dyld_insert_libraries + old_env_len;
 722   do {
 723     if (piece_start[0] == ':') piece_start++;
 724     piece_end = internal_strchr(piece_start, ':');
 725     if (!piece_end) piece_end = dyld_insert_libraries + old_env_len;
 726     if ((uptr)(piece_start - dyld_insert_libraries) > old_env_len) break;
 727     uptr piece_len = piece_end - piece_start;
 728
 729     char *filename_start =
 730         (char *)internal_memrchr(piece_start, '/', piece_len);
 731     uptr filename_len = piece_len;
 732     if (filename_start) {
 733       filename_start += 1;
 734       filename_len = piece_len - (filename_start - piece_start);
 735     } else {
 736       filename_start = piece_start;
 737     }
 738
 739     // If the current piece isn't the runtime library name,
 740     // append it to new_env.
 741     if ((dylib_name_len != filename_len) ||
 742         (internal_memcmp(filename_start, dylib_name, dylib_name_len) != 0)) {
 743       if (new_env_pos != new_env + env_name_len + 1) {
 744         new_env_pos[0] = ':';
 745         new_env_pos++;
 746       }
 747       internal_strncpy(new_env_pos, piece_start, piece_len);
 748       new_env_pos += piece_len;
 749     }
 750     // Move on to the next piece.
 751     piece_start = piece_end;
 752   } while (piece_start < old_env_end);
 753
 754   // Can't use setenv() here, because it requires the allocator to be
 755   // initialized.
 756   // FIXME: instead of filtering DYLD_INSERT_LIBRARIES here, do it in
 757   // a separate function called after InitializeAllocator().
 758   if (new_env_pos == new_env + env_name_len + 1) new_env = NULL;
 759   LeakyResetEnv(kDyldInsertLibraries, new_env);
 760 }
 761 #endif  // SANITIZER_GO
 762
 763 char **GetArgv() {
 764   return *_NSGetArgv();
 765 }
 766
 767 uptr FindAvailableMemoryRange(uptr shadow_size,
 768                               uptr alignment,
 769                               uptr left_padding) {
 770   typedef vm_region_submap_short_info_data_64_t RegionInfo;
 771   enum { kRegionInfoSize = VM_REGION_SUBMAP_SHORT_INFO_COUNT_64 };
 772   // Start searching for available memory region past PAGEZERO, which is
 773   // 4KB on 32-bit and 4GB on 64-bit.
 774   mach_vm_address_t start_address =
 775     (SANITIZER_WORDSIZE == 32) ? 0x000000001000 : 0x000100000000;
 776
 777   mach_vm_address_t address = start_address;
 778   mach_vm_address_t free_begin = start_address;
 779   kern_return_t kr = KERN_SUCCESS;
 780   while (kr == KERN_SUCCESS) {
 781     mach_vm_size_t vmsize = 0;
 782     natural_t depth = 0;
 783     RegionInfo vminfo;
 784     mach_msg_type_number_t count = kRegionInfoSize;
 785     kr = mach_vm_region_recurse(mach_task_self(), &address, &vmsize, &depth,
 786                                 (vm_region_info_t)&vminfo, &count);
 787     if (free_begin != address) {
 788       // We found a free region [free_begin..address-1].
 789       uptr shadow_address = RoundUpTo((uptr)free_begin + left_padding,
 790                                       alignment);
 791       if (shadow_address + shadow_size < (uptr)address) {
 792         return shadow_address;
 793       }
 794     }
 795     // Move to the next region.
 796     address += vmsize;
 797     free_begin = address;
 798   }
 799
 800   // We looked at all free regions and could not find one large enough.
 801   return 0;
 802 }
 803
 804 // FIXME implement on this platform.
 805 void GetMemoryProfile(fill_profile_f cb, uptr *stats, uptr stats_size) { }
 806
 807 void SignalContext::DumpAllRegisters(void *context) {
 808   Report("Register values:\n");
 809
 810   ucontext_t *ucontext = (ucontext_t*)context;
 811 # define DUMPREG64(r) \
 812     Printf("%s = 0x%016llx  ", #r, ucontext->uc_mcontext->__ss.__ ## r);
 813 # define DUMPREG32(r) \
 814     Printf("%s = 0x%08x  ", #r, ucontext->uc_mcontext->__ss.__ ## r);
 815 # define DUMPREG_(r)   Printf(" "); DUMPREG(r);
 816 # define DUMPREG__(r)  Printf("  "); DUMPREG(r);
 817 # define DUMPREG___(r) Printf("   "); DUMPREG(r);
 818
 819 # if defined(__x86_64__)
 820 #  define DUMPREG(r) DUMPREG64(r)
 821   DUMPREG(rax); DUMPREG(rbx); DUMPREG(rcx); DUMPREG(rdx); Printf("\n");
 822   DUMPREG(rdi); DUMPREG(rsi); DUMPREG(rbp); DUMPREG(rsp); Printf("\n");
 823   DUMPREG_(r8); DUMPREG_(r9); DUMPREG(r10); DUMPREG(r11); Printf("\n");
 824   DUMPREG(r12); DUMPREG(r13); DUMPREG(r14); DUMPREG(r15); Printf("\n");
 825 # elif defined(__i386__)
 826 #  define DUMPREG(r) DUMPREG32(r)
 827   DUMPREG(eax); DUMPREG(ebx); DUMPREG(ecx); DUMPREG(edx); Printf("\n");
 828   DUMPREG(edi); DUMPREG(esi); DUMPREG(ebp); DUMPREG(esp); Printf("\n");
 829 # elif defined(__aarch64__)
 830 #  define DUMPREG(r) DUMPREG64(r)
 831   DUMPREG_(x[0]); DUMPREG_(x[1]); DUMPREG_(x[2]); DUMPREG_(x[3]); Printf("\n");
 832   DUMPREG_(x[4]); DUMPREG_(x[5]); DUMPREG_(x[6]); DUMPREG_(x[7]); Printf("\n");
 833   DUMPREG_(x[8]); DUMPREG_(x[9]); DUMPREG(x[10]); DUMPREG(x[11]); Printf("\n");
 834   DUMPREG(x[12]); DUMPREG(x[13]); DUMPREG(x[14]); DUMPREG(x[15]); Printf("\n");
 835   DUMPREG(x[16]); DUMPREG(x[17]); DUMPREG(x[18]); DUMPREG(x[19]); Printf("\n");
 836   DUMPREG(x[20]); DUMPREG(x[21]); DUMPREG(x[22]); DUMPREG(x[23]); Printf("\n");
 837   DUMPREG(x[24]); DUMPREG(x[25]); DUMPREG(x[26]); DUMPREG(x[27]); Printf("\n");
 838   DUMPREG(x[28]); DUMPREG___(fp); DUMPREG___(lr); DUMPREG___(sp); Printf("\n");
 839 # elif defined(__arm__)
 840 #  define DUMPREG(r) DUMPREG32(r)
 841   DUMPREG_(r[0]); DUMPREG_(r[1]); DUMPREG_(r[2]); DUMPREG_(r[3]); Printf("\n");
 842   DUMPREG_(r[4]); DUMPREG_(r[5]); DUMPREG_(r[6]); DUMPREG_(r[7]); Printf("\n");
 843   DUMPREG_(r[8]); DUMPREG_(r[9]); DUMPREG(r[10]); DUMPREG(r[11]); Printf("\n");
 844   DUMPREG(r[12]); DUMPREG___(sp); DUMPREG___(lr); DUMPREG___(pc); Printf("\n");
 845 # else
 846 # error "Unknown architecture"
 847 # endif
 848
 849 # undef DUMPREG64
 850 # undef DUMPREG32
 851 # undef DUMPREG_
 852 # undef DUMPREG__
 853 # undef DUMPREG___
 854 # undef DUMPREG
 855 }
 856
 857 static inline bool CompareBaseAddress(const LoadedModule &a,
 858                                       const LoadedModule &b) {
 859   return a.base_address() < b.base_address();
 860 }
 861
 862 void FormatUUID(char *out, uptr size, const u8 *uuid) {
 863   internal_snprintf(out, size,
 864                     "<%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-"
 865                     "%02X%02X%02X%02X%02X%02X>",
 866                     uuid[0], uuid[1], uuid[2], uuid[3], uuid[4], uuid[5],
 867                     uuid[6], uuid[7], uuid[8], uuid[9], uuid[10], uuid[11],
 868                     uuid[12], uuid[13], uuid[14], uuid[15]);
 869 }
 870
 871 void PrintModuleMap() {
 872   Printf("Process module map:\n");
 873   MemoryMappingLayout memory_mapping(false);
 874   InternalMmapVector<LoadedModule> modules(/*initial_capacity*/ 128);
 875   memory_mapping.DumpListOfModules(&modules);
 876   InternalSort(&modules, modules.size(), CompareBaseAddress);
 877   for (uptr i = 0; i < modules.size(); ++i) {
 878     char uuid_str[128];
 879     FormatUUID(uuid_str, sizeof(uuid_str), modules[i].uuid());
 880     Printf("0x%zx-0x%zx %s (%s) %s\n", modules[i].base_address(),
 881            modules[i].max_executable_address(), modules[i].full_name(),
 882            ModuleArchToString(modules[i].arch()), uuid_str);
 883   }
 884   Printf("End of module map.\n");
 885 }
 886
 887 }  // namespace __sanitizer
 888
 889 #endif  // SANITIZER_MAC