libsanitizer/asan/asan_rtl.cpp

   1 //===-- asan_rtl.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 a part of AddressSanitizer, an address sanity checker.
  10 //
  11 // Main file of the ASan run-time library.
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "asan_activation.h"
  15 #include "asan_allocator.h"
  16 #include "asan_interceptors.h"
  17 #include "asan_interface_internal.h"
  18 #include "asan_internal.h"
  19 #include "asan_mapping.h"
  20 #include "asan_poisoning.h"
  21 #include "asan_report.h"
  22 #include "asan_stack.h"
  23 #include "asan_stats.h"
  24 #include "asan_suppressions.h"
  25 #include "asan_thread.h"
  26 #include "sanitizer_common/sanitizer_atomic.h"
  27 #include "sanitizer_common/sanitizer_flags.h"
  28 #include "sanitizer_common/sanitizer_libc.h"
  29 #include "sanitizer_common/sanitizer_symbolizer.h"
  30 #include "lsan/lsan_common.h"
  31 #include "ubsan/ubsan_init.h"
  32 #include "ubsan/ubsan_platform.h"
  33
  34 uptr __asan_shadow_memory_dynamic_address;  // Global interface symbol.
  35 int __asan_option_detect_stack_use_after_return;  // Global interface symbol.
  36 uptr *__asan_test_only_reported_buggy_pointer;  // Used only for testing asan.
  37
  38 namespace __asan {
  39
  40 uptr AsanMappingProfile[kAsanMappingProfileSize];
  41
  42 static void AsanDie() {
  43   static atomic_uint32_t num_calls;
  44   if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
  45     // Don't die twice - run a busy loop.
  46     while (1) { }
  47   }
  48   if (common_flags()->print_module_map >= 1)
  49     DumpProcessMap();
  50   if (flags()->sleep_before_dying) {
  51     Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
  52     SleepForSeconds(flags()->sleep_before_dying);
  53   }
  54   if (flags()->unmap_shadow_on_exit) {
  55     if (kMidMemBeg) {
  56       UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
  57       UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
  58     } else {
  59       if (kHighShadowEnd)
  60         UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
  61     }
  62   }
  63 }
  64
  65 static void CheckUnwind() {
  66   GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_check);
  67   stack.Print();
  68 }
  69
  70 // -------------------------- Globals --------------------- {{{1
  71 int asan_inited;
  72 bool asan_init_is_running;
  73
  74 #if !ASAN_FIXED_MAPPING
  75 uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
  76 #endif
  77
  78 // -------------------------- Misc ---------------- {{{1
  79 void ShowStatsAndAbort() {
  80   __asan_print_accumulated_stats();
  81   Die();
  82 }
  83
  84 // --------------- LowLevelAllocateCallbac ---------- {{{1
  85 static void OnLowLevelAllocate(uptr ptr, uptr size) {
  86   PoisonShadow(ptr, size, kAsanInternalHeapMagic);
  87 }
  88
  89 // -------------------------- Run-time entry ------------------- {{{1
  90 // exported functions
  91 #define ASAN_REPORT_ERROR(type, is_write, size)                     \
  92 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
  93 void __asan_report_ ## type ## size(uptr addr) {                    \
  94   GET_CALLER_PC_BP_SP;                                              \
  95   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);    \
  96 }                                                                   \
  97 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
  98 void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) {       \
  99   GET_CALLER_PC_BP_SP;                                              \
 100   ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);  \
 101 }                                                                   \
 102 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
 103 void __asan_report_ ## type ## size ## _noabort(uptr addr) {        \
 104   GET_CALLER_PC_BP_SP;                                              \
 105   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);   \
 106 }                                                                   \
 107
 108 ASAN_REPORT_ERROR(load, false, 1)
 109 ASAN_REPORT_ERROR(load, false, 2)
 110 ASAN_REPORT_ERROR(load, false, 4)
 111 ASAN_REPORT_ERROR(load, false, 8)
 112 ASAN_REPORT_ERROR(load, false, 16)
 113 ASAN_REPORT_ERROR(store, true, 1)
 114 ASAN_REPORT_ERROR(store, true, 2)
 115 ASAN_REPORT_ERROR(store, true, 4)
 116 ASAN_REPORT_ERROR(store, true, 8)
 117 ASAN_REPORT_ERROR(store, true, 16)
 118
 119 #define ASAN_REPORT_ERROR_N(type, is_write)                                 \
 120 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 121 void __asan_report_ ## type ## _n(uptr addr, uptr size) {                   \
 122   GET_CALLER_PC_BP_SP;                                                      \
 123   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);            \
 124 }                                                                           \
 125 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 126 void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) {      \
 127   GET_CALLER_PC_BP_SP;                                                      \
 128   ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);          \
 129 }                                                                           \
 130 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 131 void __asan_report_ ## type ## _n_noabort(uptr addr, uptr size) {           \
 132   GET_CALLER_PC_BP_SP;                                                      \
 133   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);           \
 134 }                                                                           \
 135
 136 ASAN_REPORT_ERROR_N(load, false)
 137 ASAN_REPORT_ERROR_N(store, true)
 138
 139 #define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg, fatal) \
 140     if (SANITIZER_MYRIAD2 && !AddrIsInMem(addr) && !AddrIsInShadow(addr))      \
 141       return;                                                                  \
 142     uptr sp = MEM_TO_SHADOW(addr);                                             \
 143     uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp)          \
 144                                         : *reinterpret_cast<u16 *>(sp);        \
 145     if (UNLIKELY(s)) {                                                         \
 146       if (UNLIKELY(size >= SHADOW_GRANULARITY ||                               \
 147                    ((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >=     \
 148                        (s8)s)) {                                               \
 149         if (__asan_test_only_reported_buggy_pointer) {                         \
 150           *__asan_test_only_reported_buggy_pointer = addr;                     \
 151         } else {                                                               \
 152           GET_CALLER_PC_BP_SP;                                                 \
 153           ReportGenericError(pc, bp, sp, addr, is_write, size, exp_arg,        \
 154                               fatal);                                          \
 155         }                                                                      \
 156       }                                                                        \
 157     }
 158
 159 #define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size)                      \
 160   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 161   void __asan_##type##size(uptr addr) {                                        \
 162     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, true)            \
 163   }                                                                            \
 164   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 165   void __asan_exp_##type##size(uptr addr, u32 exp) {                           \
 166     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp, true)          \
 167   }                                                                            \
 168   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 169   void __asan_##type##size ## _noabort(uptr addr) {                            \
 170     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, false)           \
 171   }                                                                            \
 172
 173 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
 174 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
 175 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
 176 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
 177 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
 178 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
 179 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
 180 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
 181 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
 182 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
 183
 184 extern "C"
 185 NOINLINE INTERFACE_ATTRIBUTE
 186 void __asan_loadN(uptr addr, uptr size) {
 187   if (__asan_region_is_poisoned(addr, size)) {
 188     GET_CALLER_PC_BP_SP;
 189     ReportGenericError(pc, bp, sp, addr, false, size, 0, true);
 190   }
 191 }
 192
 193 extern "C"
 194 NOINLINE INTERFACE_ATTRIBUTE
 195 void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
 196   if (__asan_region_is_poisoned(addr, size)) {
 197     GET_CALLER_PC_BP_SP;
 198     ReportGenericError(pc, bp, sp, addr, false, size, exp, true);
 199   }
 200 }
 201
 202 extern "C"
 203 NOINLINE INTERFACE_ATTRIBUTE
 204 void __asan_loadN_noabort(uptr addr, uptr size) {
 205   if (__asan_region_is_poisoned(addr, size)) {
 206     GET_CALLER_PC_BP_SP;
 207     ReportGenericError(pc, bp, sp, addr, false, size, 0, false);
 208   }
 209 }
 210
 211 extern "C"
 212 NOINLINE INTERFACE_ATTRIBUTE
 213 void __asan_storeN(uptr addr, uptr size) {
 214   if (__asan_region_is_poisoned(addr, size)) {
 215     GET_CALLER_PC_BP_SP;
 216     ReportGenericError(pc, bp, sp, addr, true, size, 0, true);
 217   }
 218 }
 219
 220 extern "C"
 221 NOINLINE INTERFACE_ATTRIBUTE
 222 void __asan_exp_storeN(uptr addr, uptr size, u32 exp) {
 223   if (__asan_region_is_poisoned(addr, size)) {
 224     GET_CALLER_PC_BP_SP;
 225     ReportGenericError(pc, bp, sp, addr, true, size, exp, true);
 226   }
 227 }
 228
 229 extern "C"
 230 NOINLINE INTERFACE_ATTRIBUTE
 231 void __asan_storeN_noabort(uptr addr, uptr size) {
 232   if (__asan_region_is_poisoned(addr, size)) {
 233     GET_CALLER_PC_BP_SP;
 234     ReportGenericError(pc, bp, sp, addr, true, size, 0, false);
 235   }
 236 }
 237
 238 // Force the linker to keep the symbols for various ASan interface functions.
 239 // We want to keep those in the executable in order to let the instrumented
 240 // dynamic libraries access the symbol even if it is not used by the executable
 241 // itself. This should help if the build system is removing dead code at link
 242 // time.
 243 static NOINLINE void force_interface_symbols() {
 244   volatile int fake_condition = 0;  // prevent dead condition elimination.
 245   // __asan_report_* functions are noreturn, so we need a switch to prevent
 246   // the compiler from removing any of them.
 247   // clang-format off
 248   switch (fake_condition) {
 249     case 1: __asan_report_load1(0); break;
 250     case 2: __asan_report_load2(0); break;
 251     case 3: __asan_report_load4(0); break;
 252     case 4: __asan_report_load8(0); break;
 253     case 5: __asan_report_load16(0); break;
 254     case 6: __asan_report_load_n(0, 0); break;
 255     case 7: __asan_report_store1(0); break;
 256     case 8: __asan_report_store2(0); break;
 257     case 9: __asan_report_store4(0); break;
 258     case 10: __asan_report_store8(0); break;
 259     case 11: __asan_report_store16(0); break;
 260     case 12: __asan_report_store_n(0, 0); break;
 261     case 13: __asan_report_exp_load1(0, 0); break;
 262     case 14: __asan_report_exp_load2(0, 0); break;
 263     case 15: __asan_report_exp_load4(0, 0); break;
 264     case 16: __asan_report_exp_load8(0, 0); break;
 265     case 17: __asan_report_exp_load16(0, 0); break;
 266     case 18: __asan_report_exp_load_n(0, 0, 0); break;
 267     case 19: __asan_report_exp_store1(0, 0); break;
 268     case 20: __asan_report_exp_store2(0, 0); break;
 269     case 21: __asan_report_exp_store4(0, 0); break;
 270     case 22: __asan_report_exp_store8(0, 0); break;
 271     case 23: __asan_report_exp_store16(0, 0); break;
 272     case 24: __asan_report_exp_store_n(0, 0, 0); break;
 273     case 25: __asan_register_globals(nullptr, 0); break;
 274     case 26: __asan_unregister_globals(nullptr, 0); break;
 275     case 27: __asan_set_death_callback(nullptr); break;
 276     case 28: __asan_set_error_report_callback(nullptr); break;
 277     case 29: __asan_handle_no_return(); break;
 278     case 30: __asan_address_is_poisoned(nullptr); break;
 279     case 31: __asan_poison_memory_region(nullptr, 0); break;
 280     case 32: __asan_unpoison_memory_region(nullptr, 0); break;
 281     case 34: __asan_before_dynamic_init(nullptr); break;
 282     case 35: __asan_after_dynamic_init(); break;
 283     case 36: __asan_poison_stack_memory(0, 0); break;
 284     case 37: __asan_unpoison_stack_memory(0, 0); break;
 285     case 38: __asan_region_is_poisoned(0, 0); break;
 286     case 39: __asan_describe_address(0); break;
 287     case 40: __asan_set_shadow_00(0, 0); break;
 288     case 41: __asan_set_shadow_f1(0, 0); break;
 289     case 42: __asan_set_shadow_f2(0, 0); break;
 290     case 43: __asan_set_shadow_f3(0, 0); break;
 291     case 44: __asan_set_shadow_f5(0, 0); break;
 292     case 45: __asan_set_shadow_f8(0, 0); break;
 293   }
 294   // clang-format on
 295 }
 296
 297 static void asan_atexit() {
 298   Printf("AddressSanitizer exit stats:\n");
 299   __asan_print_accumulated_stats();
 300   // Print AsanMappingProfile.
 301   for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
 302     if (AsanMappingProfile[i] == 0) continue;
 303     Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
 304   }
 305 }
 306
 307 static void InitializeHighMemEnd() {
 308 #if !SANITIZER_MYRIAD2
 309 #if !ASAN_FIXED_MAPPING
 310   kHighMemEnd = GetMaxUserVirtualAddress();
 311   // Increase kHighMemEnd to make sure it's properly
 312   // aligned together with kHighMemBeg:
 313   kHighMemEnd |= (GetMmapGranularity() << SHADOW_SCALE) - 1;
 314 #endif  // !ASAN_FIXED_MAPPING
 315   CHECK_EQ((kHighMemBeg % GetMmapGranularity()), 0);
 316 #endif  // !SANITIZER_MYRIAD2
 317 }
 318
 319 void PrintAddressSpaceLayout() {
 320   if (kHighMemBeg) {
 321     Printf("|| `[%p, %p]` || HighMem    ||\n",
 322            (void*)kHighMemBeg, (void*)kHighMemEnd);
 323     Printf("|| `[%p, %p]` || HighShadow ||\n",
 324            (void*)kHighShadowBeg, (void*)kHighShadowEnd);
 325   }
 326   if (kMidMemBeg) {
 327     Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
 328            (void*)kShadowGap3Beg, (void*)kShadowGap3End);
 329     Printf("|| `[%p, %p]` || MidMem     ||\n",
 330            (void*)kMidMemBeg, (void*)kMidMemEnd);
 331     Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
 332            (void*)kShadowGap2Beg, (void*)kShadowGap2End);
 333     Printf("|| `[%p, %p]` || MidShadow  ||\n",
 334            (void*)kMidShadowBeg, (void*)kMidShadowEnd);
 335   }
 336   Printf("|| `[%p, %p]` || ShadowGap  ||\n",
 337          (void*)kShadowGapBeg, (void*)kShadowGapEnd);
 338   if (kLowShadowBeg) {
 339     Printf("|| `[%p, %p]` || LowShadow  ||\n",
 340            (void*)kLowShadowBeg, (void*)kLowShadowEnd);
 341     Printf("|| `[%p, %p]` || LowMem     ||\n",
 342            (void*)kLowMemBeg, (void*)kLowMemEnd);
 343   }
 344   Printf("MemToShadow(shadow): %p %p",
 345          (void*)MEM_TO_SHADOW(kLowShadowBeg),
 346          (void*)MEM_TO_SHADOW(kLowShadowEnd));
 347   if (kHighMemBeg) {
 348     Printf(" %p %p",
 349            (void*)MEM_TO_SHADOW(kHighShadowBeg),
 350            (void*)MEM_TO_SHADOW(kHighShadowEnd));
 351   }
 352   if (kMidMemBeg) {
 353     Printf(" %p %p",
 354            (void*)MEM_TO_SHADOW(kMidShadowBeg),
 355            (void*)MEM_TO_SHADOW(kMidShadowEnd));
 356   }
 357   Printf("\n");
 358   Printf("redzone=%zu\n", (uptr)flags()->redzone);
 359   Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
 360   Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
 361   Printf("thread_local_quarantine_size_kb=%zuK\n",
 362          (uptr)flags()->thread_local_quarantine_size_kb);
 363   Printf("malloc_context_size=%zu\n",
 364          (uptr)common_flags()->malloc_context_size);
 365
 366   Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE);
 367   Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY);
 368   Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET);
 369   CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
 370   if (kMidMemBeg)
 371     CHECK(kMidShadowBeg > kLowShadowEnd &&
 372           kMidMemBeg > kMidShadowEnd &&
 373           kHighShadowBeg > kMidMemEnd);
 374 }
 375
 376 #if defined(__thumb__) && defined(__linux__)
 377 #define START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
 378 #endif
 379
 380 #ifndef START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
 381 static bool UNUSED __local_asan_dyninit = [] {
 382   MaybeStartBackgroudThread();
 383   SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
 384
 385   return false;
 386 }();
 387 #endif
 388
 389 static void AsanInitInternal() {
 390   if (LIKELY(asan_inited)) return;
 391   SanitizerToolName = "AddressSanitizer";
 392   CHECK(!asan_init_is_running && "ASan init calls itself!");
 393   asan_init_is_running = true;
 394
 395   CacheBinaryName();
 396
 397   // Initialize flags. This must be done early, because most of the
 398   // initialization steps look at flags().
 399   InitializeFlags();
 400
 401   // Stop performing init at this point if we are being loaded via
 402   // dlopen() and the platform supports it.
 403   if (SANITIZER_SUPPORTS_INIT_FOR_DLOPEN && UNLIKELY(HandleDlopenInit())) {
 404     asan_init_is_running = false;
 405     VReport(1, "AddressSanitizer init is being performed for dlopen().\n");
 406     return;
 407   }
 408
 409   AsanCheckIncompatibleRT();
 410   AsanCheckDynamicRTPrereqs();
 411   AvoidCVE_2016_2143();
 412
 413   SetCanPoisonMemory(flags()->poison_heap);
 414   SetMallocContextSize(common_flags()->malloc_context_size);
 415
 416   InitializePlatformExceptionHandlers();
 417
 418   InitializeHighMemEnd();
 419
 420   // Make sure we are not statically linked.
 421   AsanDoesNotSupportStaticLinkage();
 422
 423   // Install tool-specific callbacks in sanitizer_common.
 424   AddDieCallback(AsanDie);
 425   SetCheckUnwindCallback(CheckUnwind);
 426   SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
 427
 428   __sanitizer_set_report_path(common_flags()->log_path);
 429
 430   __asan_option_detect_stack_use_after_return =
 431       flags()->detect_stack_use_after_return;
 432
 433   __sanitizer::InitializePlatformEarly();
 434
 435   // Re-exec ourselves if we need to set additional env or command line args.
 436   MaybeReexec();
 437
 438   // Setup internal allocator callback.
 439   SetLowLevelAllocateMinAlignment(SHADOW_GRANULARITY);
 440   SetLowLevelAllocateCallback(OnLowLevelAllocate);
 441
 442   InitializeAsanInterceptors();
 443   CheckASLR();
 444
 445   // Enable system log ("adb logcat") on Android.
 446   // Doing this before interceptors are initialized crashes in:
 447   // AsanInitInternal -> android_log_write -> __interceptor_strcmp
 448   AndroidLogInit();
 449
 450   ReplaceSystemMalloc();
 451
 452   DisableCoreDumperIfNecessary();
 453
 454   InitializeShadowMemory();
 455
 456   AsanTSDInit(PlatformTSDDtor);
 457   InstallDeadlySignalHandlers(AsanOnDeadlySignal);
 458
 459   AllocatorOptions allocator_options;
 460   allocator_options.SetFrom(flags(), common_flags());
 461   InitializeAllocator(allocator_options);
 462
 463 #ifdef START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
 464   MaybeStartBackgroudThread();
 465   SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
 466 #endif
 467
 468   // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
 469   // should be set to 1 prior to initializing the threads.
 470   asan_inited = 1;
 471   asan_init_is_running = false;
 472
 473   if (flags()->atexit)
 474     Atexit(asan_atexit);
 475
 476   InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
 477
 478   // Now that ASan runtime is (mostly) initialized, deactivate it if
 479   // necessary, so that it can be re-activated when requested.
 480   if (flags()->start_deactivated)
 481     AsanDeactivate();
 482
 483   // interceptors
 484   InitTlsSize();
 485
 486   // Create main thread.
 487   AsanThread *main_thread = CreateMainThread();
 488   CHECK_EQ(0, main_thread->tid());
 489   force_interface_symbols();  // no-op.
 490   SanitizerInitializeUnwinder();
 491
 492   if (CAN_SANITIZE_LEAKS) {
 493     __lsan::InitCommonLsan();
 494     if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
 495       if (flags()->halt_on_error)
 496         Atexit(__lsan::DoLeakCheck);
 497       else
 498         Atexit(__lsan::DoRecoverableLeakCheckVoid);
 499     }
 500   }
 501
 502 #if CAN_SANITIZE_UB
 503   __ubsan::InitAsPlugin();
 504 #endif
 505
 506   InitializeSuppressions();
 507
 508   if (CAN_SANITIZE_LEAKS) {
 509     // LateInitialize() calls dlsym, which can allocate an error string buffer
 510     // in the TLS.  Let's ignore the allocation to avoid reporting a leak.
 511     __lsan::ScopedInterceptorDisabler disabler;
 512     Symbolizer::LateInitialize();
 513   } else {
 514     Symbolizer::LateInitialize();
 515   }
 516
 517   VReport(1, "AddressSanitizer Init done\n");
 518
 519   if (flags()->sleep_after_init) {
 520     Report("Sleeping for %d second(s)\n", flags()->sleep_after_init);
 521     SleepForSeconds(flags()->sleep_after_init);
 522   }
 523 }
 524
 525 // Initialize as requested from some part of ASan runtime library (interceptors,
 526 // allocator, etc).
 527 void AsanInitFromRtl() {
 528   AsanInitInternal();
 529 }
 530
 531 #if ASAN_DYNAMIC
 532 // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
 533 // (and thus normal initializers from .preinit_array or modules haven't run).
 534
 535 class AsanInitializer {
 536  public:
 537   AsanInitializer() {
 538     AsanInitFromRtl();
 539   }
 540 };
 541
 542 static AsanInitializer asan_initializer;
 543 #endif  // ASAN_DYNAMIC
 544
 545 void UnpoisonStack(uptr bottom, uptr top, const char *type) {
 546   static const uptr kMaxExpectedCleanupSize = 64 << 20;  // 64M
 547   if (top - bottom > kMaxExpectedCleanupSize) {
 548     static bool reported_warning = false;
 549     if (reported_warning)
 550       return;
 551     reported_warning = true;
 552     Report(
 553         "WARNING: ASan is ignoring requested __asan_handle_no_return: "
 554         "stack type: %s top: %p; bottom %p; size: %p (%zd)\n"
 555         "False positive error reports may follow\n"
 556         "For details see "
 557         "https://github.com/google/sanitizers/issues/189\n",
 558         type, top, bottom, top - bottom, top - bottom);
 559     return;
 560   }
 561   PoisonShadow(bottom, RoundUpTo(top - bottom, SHADOW_GRANULARITY), 0);
 562 }
 563
 564 static void UnpoisonDefaultStack() {
 565   uptr bottom, top;
 566
 567   if (AsanThread *curr_thread = GetCurrentThread()) {
 568     int local_stack;
 569     const uptr page_size = GetPageSizeCached();
 570     top = curr_thread->stack_top();
 571     bottom = ((uptr)&local_stack - page_size) & ~(page_size - 1);
 572   } else if (SANITIZER_RTEMS) {
 573     // Give up On RTEMS.
 574     return;
 575   } else {
 576     CHECK(!SANITIZER_FUCHSIA);
 577     // If we haven't seen this thread, try asking the OS for stack bounds.
 578     uptr tls_addr, tls_size, stack_size;
 579     GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr,
 580                          &tls_size);
 581     top = bottom + stack_size;
 582   }
 583
 584   UnpoisonStack(bottom, top, "default");
 585 }
 586
 587 static void UnpoisonFakeStack() {
 588   AsanThread *curr_thread = GetCurrentThread();
 589   if (curr_thread && curr_thread->has_fake_stack())
 590     curr_thread->fake_stack()->HandleNoReturn();
 591 }
 592
 593 }  // namespace __asan
 594
 595 // ---------------------- Interface ---------------- {{{1
 596 using namespace __asan;
 597
 598 void NOINLINE __asan_handle_no_return() {
 599   if (asan_init_is_running)
 600     return;
 601
 602   if (!PlatformUnpoisonStacks())
 603     UnpoisonDefaultStack();
 604
 605   UnpoisonFakeStack();
 606 }
 607
 608 extern "C" void *__asan_extra_spill_area() {
 609   AsanThread *t = GetCurrentThread();
 610   CHECK(t);
 611   return t->extra_spill_area();
 612 }
 613
 614 void __asan_handle_vfork(void *sp) {
 615   AsanThread *t = GetCurrentThread();
 616   CHECK(t);
 617   uptr bottom = t->stack_bottom();
 618   PoisonShadow(bottom, (uptr)sp - bottom, 0);
 619 }
 620
 621 void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
 622   SetUserDieCallback(callback);
 623 }
 624
 625 // Initialize as requested from instrumented application code.
 626 // We use this call as a trigger to wake up ASan from deactivated state.
 627 void __asan_init() {
 628   AsanActivate();
 629   AsanInitInternal();
 630 }
 631
 632 void __asan_version_mismatch_check() {
 633   // Do nothing.
 634 }