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_fake_stack.h"
  17 #include "asan_interceptors.h"
  18 #include "asan_interface_internal.h"
  19 #include "asan_internal.h"
  20 #include "asan_mapping.h"
  21 #include "asan_poisoning.h"
  22 #include "asan_report.h"
  23 #include "asan_stack.h"
  24 #include "asan_stats.h"
  25 #include "asan_suppressions.h"
  26 #include "asan_thread.h"
  27 #include "lsan/lsan_common.h"
  28 #include "sanitizer_common/sanitizer_atomic.h"
  29 #include "sanitizer_common/sanitizer_flags.h"
  30 #include "sanitizer_common/sanitizer_interface_internal.h"
  31 #include "sanitizer_common/sanitizer_libc.h"
  32 #include "sanitizer_common/sanitizer_symbolizer.h"
  33 #include "ubsan/ubsan_init.h"
  34 #include "ubsan/ubsan_platform.h"
  35
  36 uptr __asan_shadow_memory_dynamic_address;  // Global interface symbol.
  37 int __asan_option_detect_stack_use_after_return;  // Global interface symbol.
  38 uptr *__asan_test_only_reported_buggy_pointer;  // Used only for testing asan.
  39
  40 namespace __asan {
  41
  42 uptr AsanMappingProfile[kAsanMappingProfileSize];
  43
  44 static void AsanDie() {
  45   static atomic_uint32_t num_calls;
  46   if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
  47     // Don't die twice - run a busy loop.
  48     while (1) {
  49       internal_sched_yield();
  50     }
  51   }
  52   if (common_flags()->print_module_map >= 1)
  53     DumpProcessMap();
  54
  55   WaitForDebugger(flags()->sleep_before_dying, "before dying");
  56
  57   if (flags()->unmap_shadow_on_exit) {
  58     if (kMidMemBeg) {
  59       UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
  60       UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
  61     } else {
  62       if (kHighShadowEnd)
  63         UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
  64     }
  65   }
  66 }
  67
  68 static void CheckUnwind() {
  69   GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_check);
  70   stack.Print();
  71 }
  72
  73 // -------------------------- Globals --------------------- {{{1
  74 int asan_inited;
  75 bool asan_init_is_running;
  76 bool replace_intrin_cached;
  77
  78 #if !ASAN_FIXED_MAPPING
  79 uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
  80 #endif
  81
  82 // -------------------------- Misc ---------------- {{{1
  83 void ShowStatsAndAbort() {
  84   __asan_print_accumulated_stats();
  85   Die();
  86 }
  87
  88 NOINLINE
  89 static void ReportGenericErrorWrapper(uptr addr, bool is_write, int size,
  90                                       int exp_arg, bool fatal) {
  91   GET_CALLER_PC_BP_SP;
  92   ReportGenericError(pc, bp, sp, addr, is_write, size, exp_arg, fatal);
  93 }
  94
  95 // --------------- LowLevelAllocateCallbac ---------- {{{1
  96 static void OnLowLevelAllocate(uptr ptr, uptr size) {
  97   PoisonShadow(ptr, size, kAsanInternalHeapMagic);
  98 }
  99
 100 // -------------------------- Run-time entry ------------------- {{{1
 101 // exported functions
 102 #define ASAN_REPORT_ERROR(type, is_write, size)                     \
 103 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
 104 void __asan_report_ ## type ## size(uptr addr) {                    \
 105   GET_CALLER_PC_BP_SP;                                              \
 106   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);    \
 107 }                                                                   \
 108 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
 109 void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) {       \
 110   GET_CALLER_PC_BP_SP;                                              \
 111   ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);  \
 112 }                                                                   \
 113 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
 114 void __asan_report_ ## type ## size ## _noabort(uptr addr) {        \
 115   GET_CALLER_PC_BP_SP;                                              \
 116   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);   \
 117 }                                                                   \
 118
 119 ASAN_REPORT_ERROR(load, false, 1)
 120 ASAN_REPORT_ERROR(load, false, 2)
 121 ASAN_REPORT_ERROR(load, false, 4)
 122 ASAN_REPORT_ERROR(load, false, 8)
 123 ASAN_REPORT_ERROR(load, false, 16)
 124 ASAN_REPORT_ERROR(store, true, 1)
 125 ASAN_REPORT_ERROR(store, true, 2)
 126 ASAN_REPORT_ERROR(store, true, 4)
 127 ASAN_REPORT_ERROR(store, true, 8)
 128 ASAN_REPORT_ERROR(store, true, 16)
 129
 130 #define ASAN_REPORT_ERROR_N(type, is_write)                                 \
 131 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 132 void __asan_report_ ## type ## _n(uptr addr, uptr size) {                   \
 133   GET_CALLER_PC_BP_SP;                                                      \
 134   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);            \
 135 }                                                                           \
 136 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 137 void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) {      \
 138   GET_CALLER_PC_BP_SP;                                                      \
 139   ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);          \
 140 }                                                                           \
 141 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 142 void __asan_report_ ## type ## _n_noabort(uptr addr, uptr size) {           \
 143   GET_CALLER_PC_BP_SP;                                                      \
 144   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);           \
 145 }                                                                           \
 146
 147 ASAN_REPORT_ERROR_N(load, false)
 148 ASAN_REPORT_ERROR_N(store, true)
 149
 150 #define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg, fatal) \
 151   uptr sp = MEM_TO_SHADOW(addr);                                               \
 152   uptr s = size <= ASAN_SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp)       \
 153                                            : *reinterpret_cast<u16 *>(sp);     \
 154   if (UNLIKELY(s)) {                                                           \
 155     if (UNLIKELY(size >= ASAN_SHADOW_GRANULARITY ||                            \
 156                  ((s8)((addr & (ASAN_SHADOW_GRANULARITY - 1)) + size - 1)) >=  \
 157                      (s8)s)) {                                                 \
 158       ReportGenericErrorWrapper(addr, is_write, size, exp_arg, fatal);         \
 159     }                                                                          \
 160   }
 161
 162 #define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size)                      \
 163   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 164   void __asan_##type##size(uptr addr) {                                        \
 165     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, true)            \
 166   }                                                                            \
 167   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 168   void __asan_exp_##type##size(uptr addr, u32 exp) {                           \
 169     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp, true)          \
 170   }                                                                            \
 171   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 172   void __asan_##type##size ## _noabort(uptr addr) {                            \
 173     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, false)           \
 174   }                                                                            \
 175
 176 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
 177 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
 178 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
 179 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
 180 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
 181 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
 182 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
 183 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
 184 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
 185 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
 186
 187 extern "C"
 188 NOINLINE INTERFACE_ATTRIBUTE
 189 void __asan_loadN(uptr addr, uptr size) {
 190   if ((addr = __asan_region_is_poisoned(addr, size))) {
 191     GET_CALLER_PC_BP_SP;
 192     ReportGenericError(pc, bp, sp, addr, false, size, 0, true);
 193   }
 194 }
 195
 196 extern "C"
 197 NOINLINE INTERFACE_ATTRIBUTE
 198 void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
 199   if ((addr = __asan_region_is_poisoned(addr, size))) {
 200     GET_CALLER_PC_BP_SP;
 201     ReportGenericError(pc, bp, sp, addr, false, size, exp, true);
 202   }
 203 }
 204
 205 extern "C"
 206 NOINLINE INTERFACE_ATTRIBUTE
 207 void __asan_loadN_noabort(uptr addr, uptr size) {
 208   if ((addr = __asan_region_is_poisoned(addr, size))) {
 209     GET_CALLER_PC_BP_SP;
 210     ReportGenericError(pc, bp, sp, addr, false, size, 0, false);
 211   }
 212 }
 213
 214 extern "C"
 215 NOINLINE INTERFACE_ATTRIBUTE
 216 void __asan_storeN(uptr addr, uptr size) {
 217   if ((addr = __asan_region_is_poisoned(addr, size))) {
 218     GET_CALLER_PC_BP_SP;
 219     ReportGenericError(pc, bp, sp, addr, true, size, 0, true);
 220   }
 221 }
 222
 223 extern "C"
 224 NOINLINE INTERFACE_ATTRIBUTE
 225 void __asan_exp_storeN(uptr addr, uptr size, u32 exp) {
 226   if ((addr = __asan_region_is_poisoned(addr, size))) {
 227     GET_CALLER_PC_BP_SP;
 228     ReportGenericError(pc, bp, sp, addr, true, size, exp, true);
 229   }
 230 }
 231
 232 extern "C"
 233 NOINLINE INTERFACE_ATTRIBUTE
 234 void __asan_storeN_noabort(uptr addr, uptr size) {
 235   if ((addr = __asan_region_is_poisoned(addr, size))) {
 236     GET_CALLER_PC_BP_SP;
 237     ReportGenericError(pc, bp, sp, addr, true, size, 0, false);
 238   }
 239 }
 240
 241 // Force the linker to keep the symbols for various ASan interface functions.
 242 // We want to keep those in the executable in order to let the instrumented
 243 // dynamic libraries access the symbol even if it is not used by the executable
 244 // itself. This should help if the build system is removing dead code at link
 245 // time.
 246 static NOINLINE void force_interface_symbols() {
 247   volatile int fake_condition = 0;  // prevent dead condition elimination.
 248   // __asan_report_* functions are noreturn, so we need a switch to prevent
 249   // the compiler from removing any of them.
 250   // clang-format off
 251   switch (fake_condition) {
 252     case 1: __asan_report_load1(0); break;
 253     case 2: __asan_report_load2(0); break;
 254     case 3: __asan_report_load4(0); break;
 255     case 4: __asan_report_load8(0); break;
 256     case 5: __asan_report_load16(0); break;
 257     case 6: __asan_report_load_n(0, 0); break;
 258     case 7: __asan_report_store1(0); break;
 259     case 8: __asan_report_store2(0); break;
 260     case 9: __asan_report_store4(0); break;
 261     case 10: __asan_report_store8(0); break;
 262     case 11: __asan_report_store16(0); break;
 263     case 12: __asan_report_store_n(0, 0); break;
 264     case 13: __asan_report_exp_load1(0, 0); break;
 265     case 14: __asan_report_exp_load2(0, 0); break;
 266     case 15: __asan_report_exp_load4(0, 0); break;
 267     case 16: __asan_report_exp_load8(0, 0); break;
 268     case 17: __asan_report_exp_load16(0, 0); break;
 269     case 18: __asan_report_exp_load_n(0, 0, 0); break;
 270     case 19: __asan_report_exp_store1(0, 0); break;
 271     case 20: __asan_report_exp_store2(0, 0); break;
 272     case 21: __asan_report_exp_store4(0, 0); break;
 273     case 22: __asan_report_exp_store8(0, 0); break;
 274     case 23: __asan_report_exp_store16(0, 0); break;
 275     case 24: __asan_report_exp_store_n(0, 0, 0); break;
 276     case 25: __asan_register_globals(nullptr, 0); break;
 277     case 26: __asan_unregister_globals(nullptr, 0); break;
 278     case 27: __asan_set_death_callback(nullptr); break;
 279     case 28: __asan_set_error_report_callback(nullptr); break;
 280     case 29: __asan_handle_no_return(); break;
 281     case 30: __asan_address_is_poisoned(nullptr); break;
 282     case 31: __asan_poison_memory_region(nullptr, 0); break;
 283     case 32: __asan_unpoison_memory_region(nullptr, 0); break;
 284     case 34: __asan_before_dynamic_init(nullptr); break;
 285     case 35: __asan_after_dynamic_init(); break;
 286     case 36: __asan_poison_stack_memory(0, 0); break;
 287     case 37: __asan_unpoison_stack_memory(0, 0); break;
 288     case 38: __asan_region_is_poisoned(0, 0); break;
 289     case 39: __asan_describe_address(0); break;
 290     case 40: __asan_set_shadow_00(0, 0); break;
 291     case 41: __asan_set_shadow_01(0, 0); break;
 292     case 42: __asan_set_shadow_02(0, 0); break;
 293     case 43: __asan_set_shadow_03(0, 0); break;
 294     case 44: __asan_set_shadow_04(0, 0); break;
 295     case 45: __asan_set_shadow_05(0, 0); break;
 296     case 46: __asan_set_shadow_06(0, 0); break;
 297     case 47: __asan_set_shadow_07(0, 0); break;
 298     case 48: __asan_set_shadow_f1(0, 0); break;
 299     case 49: __asan_set_shadow_f2(0, 0); break;
 300     case 50: __asan_set_shadow_f3(0, 0); break;
 301     case 51: __asan_set_shadow_f5(0, 0); break;
 302     case 52: __asan_set_shadow_f8(0, 0); break;
 303   }
 304   // clang-format on
 305 }
 306
 307 static void asan_atexit() {
 308   Printf("AddressSanitizer exit stats:\n");
 309   __asan_print_accumulated_stats();
 310   // Print AsanMappingProfile.
 311   for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
 312     if (AsanMappingProfile[i] == 0) continue;
 313     Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
 314   }
 315 }
 316
 317 static void InitializeHighMemEnd() {
 318 #if !ASAN_FIXED_MAPPING
 319   kHighMemEnd = GetMaxUserVirtualAddress();
 320   // Increase kHighMemEnd to make sure it's properly
 321   // aligned together with kHighMemBeg:
 322   kHighMemEnd |= (GetMmapGranularity() << ASAN_SHADOW_SCALE) - 1;
 323 #endif  // !ASAN_FIXED_MAPPING
 324   CHECK_EQ((kHighMemBeg % GetMmapGranularity()), 0);
 325 }
 326
 327 void PrintAddressSpaceLayout() {
 328   if (kHighMemBeg) {
 329     Printf("|| `[%p, %p]` || HighMem    ||\n",
 330            (void*)kHighMemBeg, (void*)kHighMemEnd);
 331     Printf("|| `[%p, %p]` || HighShadow ||\n",
 332            (void*)kHighShadowBeg, (void*)kHighShadowEnd);
 333   }
 334   if (kMidMemBeg) {
 335     Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
 336            (void*)kShadowGap3Beg, (void*)kShadowGap3End);
 337     Printf("|| `[%p, %p]` || MidMem     ||\n",
 338            (void*)kMidMemBeg, (void*)kMidMemEnd);
 339     Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
 340            (void*)kShadowGap2Beg, (void*)kShadowGap2End);
 341     Printf("|| `[%p, %p]` || MidShadow  ||\n",
 342            (void*)kMidShadowBeg, (void*)kMidShadowEnd);
 343   }
 344   Printf("|| `[%p, %p]` || ShadowGap  ||\n",
 345          (void*)kShadowGapBeg, (void*)kShadowGapEnd);
 346   if (kLowShadowBeg) {
 347     Printf("|| `[%p, %p]` || LowShadow  ||\n",
 348            (void*)kLowShadowBeg, (void*)kLowShadowEnd);
 349     Printf("|| `[%p, %p]` || LowMem     ||\n",
 350            (void*)kLowMemBeg, (void*)kLowMemEnd);
 351   }
 352   Printf("MemToShadow(shadow): %p %p",
 353          (void*)MEM_TO_SHADOW(kLowShadowBeg),
 354          (void*)MEM_TO_SHADOW(kLowShadowEnd));
 355   if (kHighMemBeg) {
 356     Printf(" %p %p",
 357            (void*)MEM_TO_SHADOW(kHighShadowBeg),
 358            (void*)MEM_TO_SHADOW(kHighShadowEnd));
 359   }
 360   if (kMidMemBeg) {
 361     Printf(" %p %p",
 362            (void*)MEM_TO_SHADOW(kMidShadowBeg),
 363            (void*)MEM_TO_SHADOW(kMidShadowEnd));
 364   }
 365   Printf("\n");
 366   Printf("redzone=%zu\n", (uptr)flags()->redzone);
 367   Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
 368   Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
 369   Printf("thread_local_quarantine_size_kb=%zuK\n",
 370          (uptr)flags()->thread_local_quarantine_size_kb);
 371   Printf("malloc_context_size=%zu\n",
 372          (uptr)common_flags()->malloc_context_size);
 373
 374   Printf("SHADOW_SCALE: %d\n", (int)ASAN_SHADOW_SCALE);
 375   Printf("SHADOW_GRANULARITY: %d\n", (int)ASAN_SHADOW_GRANULARITY);
 376   Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)ASAN_SHADOW_OFFSET);
 377   CHECK(ASAN_SHADOW_SCALE >= 3 && ASAN_SHADOW_SCALE <= 7);
 378   if (kMidMemBeg)
 379     CHECK(kMidShadowBeg > kLowShadowEnd &&
 380           kMidMemBeg > kMidShadowEnd &&
 381           kHighShadowBeg > kMidMemEnd);
 382 }
 383
 384 static void AsanInitInternal() {
 385   if (LIKELY(asan_inited)) return;
 386   SanitizerToolName = "AddressSanitizer";
 387   CHECK(!asan_init_is_running && "ASan init calls itself!");
 388   asan_init_is_running = true;
 389
 390   CacheBinaryName();
 391
 392   // Initialize flags. This must be done early, because most of the
 393   // initialization steps look at flags().
 394   InitializeFlags();
 395
 396   WaitForDebugger(flags()->sleep_before_init, "before init");
 397
 398   // Stop performing init at this point if we are being loaded via
 399   // dlopen() and the platform supports it.
 400   if (SANITIZER_SUPPORTS_INIT_FOR_DLOPEN && UNLIKELY(HandleDlopenInit())) {
 401     asan_init_is_running = false;
 402     VReport(1, "AddressSanitizer init is being performed for dlopen().\n");
 403     return;
 404   }
 405
 406   AsanCheckIncompatibleRT();
 407   AsanCheckDynamicRTPrereqs();
 408   AvoidCVE_2016_2143();
 409
 410   SetCanPoisonMemory(flags()->poison_heap);
 411   SetMallocContextSize(common_flags()->malloc_context_size);
 412
 413   InitializePlatformExceptionHandlers();
 414
 415   InitializeHighMemEnd();
 416
 417   // Make sure we are not statically linked.
 418   AsanDoesNotSupportStaticLinkage();
 419
 420   // Install tool-specific callbacks in sanitizer_common.
 421   AddDieCallback(AsanDie);
 422   SetCheckUnwindCallback(CheckUnwind);
 423   SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
 424
 425   __sanitizer_set_report_path(common_flags()->log_path);
 426
 427   __asan_option_detect_stack_use_after_return =
 428       flags()->detect_stack_use_after_return;
 429
 430   __sanitizer::InitializePlatformEarly();
 431
 432   // Setup internal allocator callback.
 433   SetLowLevelAllocateMinAlignment(ASAN_SHADOW_GRANULARITY);
 434   SetLowLevelAllocateCallback(OnLowLevelAllocate);
 435
 436   InitializeAsanInterceptors();
 437   CheckASLR();
 438
 439   // Enable system log ("adb logcat") on Android.
 440   // Doing this before interceptors are initialized crashes in:
 441   // AsanInitInternal -> android_log_write -> __interceptor_strcmp
 442   AndroidLogInit();
 443
 444   ReplaceSystemMalloc();
 445
 446   DisableCoreDumperIfNecessary();
 447
 448   InitializeShadowMemory();
 449
 450   AsanTSDInit(PlatformTSDDtor);
 451   InstallDeadlySignalHandlers(AsanOnDeadlySignal);
 452
 453   AllocatorOptions allocator_options;
 454   allocator_options.SetFrom(flags(), common_flags());
 455   InitializeAllocator(allocator_options);
 456
 457   if (SANITIZER_START_BACKGROUND_THREAD_IN_ASAN_INTERNAL)
 458     MaybeStartBackgroudThread();
 459
 460   // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
 461   // should be set to 1 prior to initializing the threads.
 462   replace_intrin_cached = flags()->replace_intrin;
 463   asan_inited = 1;
 464   asan_init_is_running = false;
 465
 466   if (flags()->atexit)
 467     Atexit(asan_atexit);
 468
 469   InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
 470
 471   // Now that ASan runtime is (mostly) initialized, deactivate it if
 472   // necessary, so that it can be re-activated when requested.
 473   if (flags()->start_deactivated)
 474     AsanDeactivate();
 475
 476   // interceptors
 477   InitTlsSize();
 478
 479   // Create main thread.
 480   AsanThread *main_thread = CreateMainThread();
 481   CHECK_EQ(0, main_thread->tid());
 482   force_interface_symbols();  // no-op.
 483   SanitizerInitializeUnwinder();
 484
 485   if (CAN_SANITIZE_LEAKS) {
 486     __lsan::InitCommonLsan();
 487     InstallAtExitCheckLeaks();
 488   }
 489
 490 #if CAN_SANITIZE_UB
 491   __ubsan::InitAsPlugin();
 492 #endif
 493
 494   InitializeSuppressions();
 495
 496   if (CAN_SANITIZE_LEAKS) {
 497     // LateInitialize() calls dlsym, which can allocate an error string buffer
 498     // in the TLS.  Let's ignore the allocation to avoid reporting a leak.
 499     __lsan::ScopedInterceptorDisabler disabler;
 500     Symbolizer::LateInitialize();
 501   } else {
 502     Symbolizer::LateInitialize();
 503   }
 504
 505   VReport(1, "AddressSanitizer Init done\n");
 506
 507   WaitForDebugger(flags()->sleep_after_init, "after init");
 508 }
 509
 510 // Initialize as requested from some part of ASan runtime library (interceptors,
 511 // allocator, etc).
 512 void AsanInitFromRtl() {
 513   AsanInitInternal();
 514 }
 515
 516 #if ASAN_DYNAMIC
 517 // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
 518 // (and thus normal initializers from .preinit_array or modules haven't run).
 519
 520 class AsanInitializer {
 521  public:
 522   AsanInitializer() {
 523     AsanInitFromRtl();
 524   }
 525 };
 526
 527 static AsanInitializer asan_initializer;
 528 #endif  // ASAN_DYNAMIC
 529
 530 void UnpoisonStack(uptr bottom, uptr top, const char *type) {
 531   static const uptr kMaxExpectedCleanupSize = 64 << 20;  // 64M
 532   if (top - bottom > kMaxExpectedCleanupSize) {
 533     static bool reported_warning = false;
 534     if (reported_warning)
 535       return;
 536     reported_warning = true;
 537     Report(
 538         "WARNING: ASan is ignoring requested __asan_handle_no_return: "
 539         "stack type: %s top: %p; bottom %p; size: %p (%zd)\n"
 540         "False positive error reports may follow\n"
 541         "For details see "
 542         "https://github.com/google/sanitizers/issues/189\n",
 543         type, (void *)top, (void *)bottom, (void *)(top - bottom),
 544         top - bottom);
 545     return;
 546   }
 547   PoisonShadow(bottom, RoundUpTo(top - bottom, ASAN_SHADOW_GRANULARITY), 0);
 548 }
 549
 550 static void UnpoisonDefaultStack() {
 551   uptr bottom, top;
 552
 553   if (AsanThread *curr_thread = GetCurrentThread()) {
 554     int local_stack;
 555     const uptr page_size = GetPageSizeCached();
 556     top = curr_thread->stack_top();
 557     bottom = ((uptr)&local_stack - page_size) & ~(page_size - 1);
 558   } else {
 559     CHECK(!SANITIZER_FUCHSIA);
 560     // If we haven't seen this thread, try asking the OS for stack bounds.
 561     uptr tls_addr, tls_size, stack_size;
 562     GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr,
 563                          &tls_size);
 564     top = bottom + stack_size;
 565   }
 566
 567   UnpoisonStack(bottom, top, "default");
 568 }
 569
 570 static void UnpoisonFakeStack() {
 571   AsanThread *curr_thread = GetCurrentThread();
 572   if (!curr_thread)
 573     return;
 574   FakeStack *stack = curr_thread->get_fake_stack();
 575   if (!stack)
 576     return;
 577   stack->HandleNoReturn();
 578 }
 579
 580 }  // namespace __asan
 581
 582 // ---------------------- Interface ---------------- {{{1
 583 using namespace __asan;
 584
 585 void NOINLINE __asan_handle_no_return() {
 586   if (asan_init_is_running)
 587     return;
 588
 589   if (!PlatformUnpoisonStacks())
 590     UnpoisonDefaultStack();
 591
 592   UnpoisonFakeStack();
 593 }
 594
 595 extern "C" void *__asan_extra_spill_area() {
 596   AsanThread *t = GetCurrentThread();
 597   CHECK(t);
 598   return t->extra_spill_area();
 599 }
 600
 601 void __asan_handle_vfork(void *sp) {
 602   AsanThread *t = GetCurrentThread();
 603   CHECK(t);
 604   uptr bottom = t->stack_bottom();
 605   PoisonShadow(bottom, (uptr)sp - bottom, 0);
 606 }
 607
 608 void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
 609   SetUserDieCallback(callback);
 610 }
 611
 612 // Initialize as requested from instrumented application code.
 613 // We use this call as a trigger to wake up ASan from deactivated state.
 614 void __asan_init() {
 615   AsanActivate();
 616   AsanInitInternal();
 617 }
 618
 619 void __asan_version_mismatch_check() {
 620   // Do nothing.
 621 }