libsanitizer/asan/asan_rtl.cc

   1 //===-- asan_rtl.cc -------------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of AddressSanitizer, an address sanity checker.
   9 //
  10 // Main file of the ASan run-time library.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "asan_activation.h"
  14 #include "asan_allocator.h"
  15 #include "asan_interceptors.h"
  16 #include "asan_interface_internal.h"
  17 #include "asan_internal.h"
  18 #include "asan_mapping.h"
  19 #include "asan_poisoning.h"
  20 #include "asan_report.h"
  21 #include "asan_stack.h"
  22 #include "asan_stats.h"
  23 #include "asan_suppressions.h"
  24 #include "asan_thread.h"
  25 #include "sanitizer_common/sanitizer_atomic.h"
  26 #include "sanitizer_common/sanitizer_flags.h"
  27 #include "sanitizer_common/sanitizer_libc.h"
  28 #include "sanitizer_common/sanitizer_symbolizer.h"
  29 #include "lsan/lsan_common.h"
  30 #include "ubsan/ubsan_init.h"
  31 #include "ubsan/ubsan_platform.h"
  32
  33 uptr __asan_shadow_memory_dynamic_address;  // Global interface symbol.
  34 int __asan_option_detect_stack_use_after_return;  // Global interface symbol.
  35 uptr *__asan_test_only_reported_buggy_pointer;  // Used only for testing asan.
  36
  37 namespace __asan {
  38
  39 uptr AsanMappingProfile[kAsanMappingProfileSize];
  40
  41 static void AsanDie() {
  42   static atomic_uint32_t num_calls;
  43   if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
  44     // Don't die twice - run a busy loop.
  45     while (1) { }
  46   }
  47   if (common_flags()->print_module_map >= 1) PrintModuleMap();
  48   if (flags()->sleep_before_dying) {
  49     Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
  50     SleepForSeconds(flags()->sleep_before_dying);
  51   }
  52   if (flags()->unmap_shadow_on_exit) {
  53     if (kMidMemBeg) {
  54       UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
  55       UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
  56     } else {
  57       UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
  58     }
  59   }
  60 }
  61
  62 static void AsanCheckFailed(const char *file, int line, const char *cond,
  63                             u64 v1, u64 v2) {
  64   Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
  65          line, cond, (uptr)v1, (uptr)v2);
  66   // FIXME: check for infinite recursion without a thread-local counter here.
  67   PRINT_CURRENT_STACK_CHECK();
  68   Die();
  69 }
  70
  71 // -------------------------- Globals --------------------- {{{1
  72 int asan_inited;
  73 bool asan_init_is_running;
  74
  75 #if !ASAN_FIXED_MAPPING
  76 uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
  77 #endif
  78
  79 // -------------------------- Misc ---------------- {{{1
  80 void ShowStatsAndAbort() {
  81   __asan_print_accumulated_stats();
  82   Die();
  83 }
  84
  85 // --------------- LowLevelAllocateCallbac ---------- {{{1
  86 static void OnLowLevelAllocate(uptr ptr, uptr size) {
  87   PoisonShadow(ptr, size, kAsanInternalHeapMagic);
  88 }
  89
  90 // -------------------------- Run-time entry ------------------- {{{1
  91 // exported functions
  92 #define ASAN_REPORT_ERROR(type, is_write, size)                     \
  93 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
  94 void __asan_report_ ## type ## size(uptr addr) {                    \
  95   GET_CALLER_PC_BP_SP;                                              \
  96   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);    \
  97 }                                                                   \
  98 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
  99 void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) {       \
 100   GET_CALLER_PC_BP_SP;                                              \
 101   ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);  \
 102 }                                                                   \
 103 extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
 104 void __asan_report_ ## type ## size ## _noabort(uptr addr) {        \
 105   GET_CALLER_PC_BP_SP;                                              \
 106   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);   \
 107 }                                                                   \
 108
 109 ASAN_REPORT_ERROR(load, false, 1)
 110 ASAN_REPORT_ERROR(load, false, 2)
 111 ASAN_REPORT_ERROR(load, false, 4)
 112 ASAN_REPORT_ERROR(load, false, 8)
 113 ASAN_REPORT_ERROR(load, false, 16)
 114 ASAN_REPORT_ERROR(store, true, 1)
 115 ASAN_REPORT_ERROR(store, true, 2)
 116 ASAN_REPORT_ERROR(store, true, 4)
 117 ASAN_REPORT_ERROR(store, true, 8)
 118 ASAN_REPORT_ERROR(store, true, 16)
 119
 120 #define ASAN_REPORT_ERROR_N(type, is_write)                                 \
 121 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 122 void __asan_report_ ## type ## _n(uptr addr, uptr size) {                   \
 123   GET_CALLER_PC_BP_SP;                                                      \
 124   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);            \
 125 }                                                                           \
 126 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 127 void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) {      \
 128   GET_CALLER_PC_BP_SP;                                                      \
 129   ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);          \
 130 }                                                                           \
 131 extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
 132 void __asan_report_ ## type ## _n_noabort(uptr addr, uptr size) {           \
 133   GET_CALLER_PC_BP_SP;                                                      \
 134   ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);           \
 135 }                                                                           \
 136
 137 ASAN_REPORT_ERROR_N(load, false)
 138 ASAN_REPORT_ERROR_N(store, true)
 139
 140 #define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg, fatal) \
 141     uptr sp = MEM_TO_SHADOW(addr);                                             \
 142     uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp)          \
 143                                         : *reinterpret_cast<u16 *>(sp);        \
 144     if (UNLIKELY(s)) {                                                         \
 145       if (UNLIKELY(size >= SHADOW_GRANULARITY ||                               \
 146                    ((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >=     \
 147                        (s8)s)) {                                               \
 148         if (__asan_test_only_reported_buggy_pointer) {                         \
 149           *__asan_test_only_reported_buggy_pointer = addr;                     \
 150         } else {                                                               \
 151           GET_CALLER_PC_BP_SP;                                                 \
 152           ReportGenericError(pc, bp, sp, addr, is_write, size, exp_arg,        \
 153                               fatal);                                          \
 154         }                                                                      \
 155       }                                                                        \
 156     }
 157
 158 #define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size)                      \
 159   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 160   void __asan_##type##size(uptr addr) {                                        \
 161     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, true)            \
 162   }                                                                            \
 163   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 164   void __asan_exp_##type##size(uptr addr, u32 exp) {                           \
 165     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp, true)          \
 166   }                                                                            \
 167   extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
 168   void __asan_##type##size ## _noabort(uptr addr) {                            \
 169     ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, false)           \
 170   }                                                                            \
 171
 172 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
 173 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
 174 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
 175 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
 176 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
 177 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
 178 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
 179 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
 180 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
 181 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
 182
 183 extern "C"
 184 NOINLINE INTERFACE_ATTRIBUTE
 185 void __asan_loadN(uptr addr, uptr size) {
 186   if (__asan_region_is_poisoned(addr, size)) {
 187     GET_CALLER_PC_BP_SP;
 188     ReportGenericError(pc, bp, sp, addr, false, size, 0, true);
 189   }
 190 }
 191
 192 extern "C"
 193 NOINLINE INTERFACE_ATTRIBUTE
 194 void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
 195   if (__asan_region_is_poisoned(addr, size)) {
 196     GET_CALLER_PC_BP_SP;
 197     ReportGenericError(pc, bp, sp, addr, false, size, exp, true);
 198   }
 199 }
 200
 201 extern "C"
 202 NOINLINE INTERFACE_ATTRIBUTE
 203 void __asan_loadN_noabort(uptr addr, uptr size) {
 204   if (__asan_region_is_poisoned(addr, size)) {
 205     GET_CALLER_PC_BP_SP;
 206     ReportGenericError(pc, bp, sp, addr, false, size, 0, false);
 207   }
 208 }
 209
 210 extern "C"
 211 NOINLINE INTERFACE_ATTRIBUTE
 212 void __asan_storeN(uptr addr, uptr size) {
 213   if (__asan_region_is_poisoned(addr, size)) {
 214     GET_CALLER_PC_BP_SP;
 215     ReportGenericError(pc, bp, sp, addr, true, size, 0, true);
 216   }
 217 }
 218
 219 extern "C"
 220 NOINLINE INTERFACE_ATTRIBUTE
 221 void __asan_exp_storeN(uptr addr, uptr size, u32 exp) {
 222   if (__asan_region_is_poisoned(addr, size)) {
 223     GET_CALLER_PC_BP_SP;
 224     ReportGenericError(pc, bp, sp, addr, true, size, exp, true);
 225   }
 226 }
 227
 228 extern "C"
 229 NOINLINE INTERFACE_ATTRIBUTE
 230 void __asan_storeN_noabort(uptr addr, uptr size) {
 231   if (__asan_region_is_poisoned(addr, size)) {
 232     GET_CALLER_PC_BP_SP;
 233     ReportGenericError(pc, bp, sp, addr, true, size, 0, false);
 234   }
 235 }
 236
 237 // Force the linker to keep the symbols for various ASan interface functions.
 238 // We want to keep those in the executable in order to let the instrumented
 239 // dynamic libraries access the symbol even if it is not used by the executable
 240 // itself. This should help if the build system is removing dead code at link
 241 // time.
 242 static NOINLINE void force_interface_symbols() {
 243   volatile int fake_condition = 0;  // prevent dead condition elimination.
 244   // __asan_report_* functions are noreturn, so we need a switch to prevent
 245   // the compiler from removing any of them.
 246   // clang-format off
 247   switch (fake_condition) {
 248     case 1: __asan_report_load1(0); break;
 249     case 2: __asan_report_load2(0); break;
 250     case 3: __asan_report_load4(0); break;
 251     case 4: __asan_report_load8(0); break;
 252     case 5: __asan_report_load16(0); break;
 253     case 6: __asan_report_load_n(0, 0); break;
 254     case 7: __asan_report_store1(0); break;
 255     case 8: __asan_report_store2(0); break;
 256     case 9: __asan_report_store4(0); break;
 257     case 10: __asan_report_store8(0); break;
 258     case 11: __asan_report_store16(0); break;
 259     case 12: __asan_report_store_n(0, 0); break;
 260     case 13: __asan_report_exp_load1(0, 0); break;
 261     case 14: __asan_report_exp_load2(0, 0); break;
 262     case 15: __asan_report_exp_load4(0, 0); break;
 263     case 16: __asan_report_exp_load8(0, 0); break;
 264     case 17: __asan_report_exp_load16(0, 0); break;
 265     case 18: __asan_report_exp_load_n(0, 0, 0); break;
 266     case 19: __asan_report_exp_store1(0, 0); break;
 267     case 20: __asan_report_exp_store2(0, 0); break;
 268     case 21: __asan_report_exp_store4(0, 0); break;
 269     case 22: __asan_report_exp_store8(0, 0); break;
 270     case 23: __asan_report_exp_store16(0, 0); break;
 271     case 24: __asan_report_exp_store_n(0, 0, 0); break;
 272     case 25: __asan_register_globals(nullptr, 0); break;
 273     case 26: __asan_unregister_globals(nullptr, 0); break;
 274     case 27: __asan_set_death_callback(nullptr); break;
 275     case 28: __asan_set_error_report_callback(nullptr); break;
 276     case 29: __asan_handle_no_return(); break;
 277     case 30: __asan_address_is_poisoned(nullptr); break;
 278     case 31: __asan_poison_memory_region(nullptr, 0); break;
 279     case 32: __asan_unpoison_memory_region(nullptr, 0); break;
 280     case 34: __asan_before_dynamic_init(nullptr); break;
 281     case 35: __asan_after_dynamic_init(); break;
 282     case 36: __asan_poison_stack_memory(0, 0); break;
 283     case 37: __asan_unpoison_stack_memory(0, 0); break;
 284     case 38: __asan_region_is_poisoned(0, 0); break;
 285     case 39: __asan_describe_address(0); break;
 286     case 40: __asan_set_shadow_00(0, 0); break;
 287     case 41: __asan_set_shadow_f1(0, 0); break;
 288     case 42: __asan_set_shadow_f2(0, 0); break;
 289     case 43: __asan_set_shadow_f3(0, 0); break;
 290     case 44: __asan_set_shadow_f5(0, 0); break;
 291     case 45: __asan_set_shadow_f8(0, 0); break;
 292   }
 293   // clang-format on
 294 }
 295
 296 static void asan_atexit() {
 297   Printf("AddressSanitizer exit stats:\n");
 298   __asan_print_accumulated_stats();
 299   // Print AsanMappingProfile.
 300   for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
 301     if (AsanMappingProfile[i] == 0) continue;
 302     Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
 303   }
 304 }
 305
 306 static void InitializeHighMemEnd() {
 307 #if !ASAN_FIXED_MAPPING
 308   kHighMemEnd = GetMaxVirtualAddress();
 309   // Increase kHighMemEnd to make sure it's properly
 310   // aligned together with kHighMemBeg:
 311   kHighMemEnd |= SHADOW_GRANULARITY * GetMmapGranularity() - 1;
 312 #endif  // !ASAN_FIXED_MAPPING
 313   CHECK_EQ((kHighMemBeg % GetMmapGranularity()), 0);
 314 }
 315
 316 void PrintAddressSpaceLayout() {
 317   Printf("|| `[%p, %p]` || HighMem    ||\n",
 318          (void*)kHighMemBeg, (void*)kHighMemEnd);
 319   Printf("|| `[%p, %p]` || HighShadow ||\n",
 320          (void*)kHighShadowBeg, (void*)kHighShadowEnd);
 321   if (kMidMemBeg) {
 322     Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
 323            (void*)kShadowGap3Beg, (void*)kShadowGap3End);
 324     Printf("|| `[%p, %p]` || MidMem     ||\n",
 325            (void*)kMidMemBeg, (void*)kMidMemEnd);
 326     Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
 327            (void*)kShadowGap2Beg, (void*)kShadowGap2End);
 328     Printf("|| `[%p, %p]` || MidShadow  ||\n",
 329            (void*)kMidShadowBeg, (void*)kMidShadowEnd);
 330   }
 331   Printf("|| `[%p, %p]` || ShadowGap  ||\n",
 332          (void*)kShadowGapBeg, (void*)kShadowGapEnd);
 333   if (kLowShadowBeg) {
 334     Printf("|| `[%p, %p]` || LowShadow  ||\n",
 335            (void*)kLowShadowBeg, (void*)kLowShadowEnd);
 336     Printf("|| `[%p, %p]` || LowMem     ||\n",
 337            (void*)kLowMemBeg, (void*)kLowMemEnd);
 338   }
 339   Printf("MemToShadow(shadow): %p %p %p %p",
 340          (void*)MEM_TO_SHADOW(kLowShadowBeg),
 341          (void*)MEM_TO_SHADOW(kLowShadowEnd),
 342          (void*)MEM_TO_SHADOW(kHighShadowBeg),
 343          (void*)MEM_TO_SHADOW(kHighShadowEnd));
 344   if (kMidMemBeg) {
 345     Printf(" %p %p",
 346            (void*)MEM_TO_SHADOW(kMidShadowBeg),
 347            (void*)MEM_TO_SHADOW(kMidShadowEnd));
 348   }
 349   Printf("\n");
 350   Printf("redzone=%zu\n", (uptr)flags()->redzone);
 351   Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
 352   Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
 353   Printf("thread_local_quarantine_size_kb=%zuK\n",
 354          (uptr)flags()->thread_local_quarantine_size_kb);
 355   Printf("malloc_context_size=%zu\n",
 356          (uptr)common_flags()->malloc_context_size);
 357
 358   Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE);
 359   Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY);
 360   Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET);
 361   CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
 362   if (kMidMemBeg)
 363     CHECK(kMidShadowBeg > kLowShadowEnd &&
 364           kMidMemBeg > kMidShadowEnd &&
 365           kHighShadowBeg > kMidMemEnd);
 366 }
 367
 368 static void AsanInitInternal() {
 369   if (LIKELY(asan_inited)) return;
 370   SanitizerToolName = "AddressSanitizer";
 371   CHECK(!asan_init_is_running && "ASan init calls itself!");
 372   asan_init_is_running = true;
 373
 374   CacheBinaryName();
 375
 376   // Initialize flags. This must be done early, because most of the
 377   // initialization steps look at flags().
 378   InitializeFlags();
 379
 380   AsanCheckIncompatibleRT();
 381   AsanCheckDynamicRTPrereqs();
 382   AvoidCVE_2016_2143();
 383
 384   SetCanPoisonMemory(flags()->poison_heap);
 385   SetMallocContextSize(common_flags()->malloc_context_size);
 386
 387   InitializePlatformExceptionHandlers();
 388
 389   InitializeHighMemEnd();
 390
 391   // Make sure we are not statically linked.
 392   AsanDoesNotSupportStaticLinkage();
 393
 394   // Install tool-specific callbacks in sanitizer_common.
 395   AddDieCallback(AsanDie);
 396   SetCheckFailedCallback(AsanCheckFailed);
 397   SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
 398
 399   __sanitizer_set_report_path(common_flags()->log_path);
 400
 401   __asan_option_detect_stack_use_after_return =
 402       flags()->detect_stack_use_after_return;
 403
 404   // Re-exec ourselves if we need to set additional env or command line args.
 405   MaybeReexec();
 406
 407   // Setup internal allocator callback.
 408   SetLowLevelAllocateCallback(OnLowLevelAllocate);
 409
 410   InitializeAsanInterceptors();
 411
 412   // Enable system log ("adb logcat") on Android.
 413   // Doing this before interceptors are initialized crashes in:
 414   // AsanInitInternal -> android_log_write -> __interceptor_strcmp
 415   AndroidLogInit();
 416
 417   ReplaceSystemMalloc();
 418
 419   DisableCoreDumperIfNecessary();
 420
 421   InitializeShadowMemory();
 422
 423   AsanTSDInit(PlatformTSDDtor);
 424   InstallDeadlySignalHandlers(AsanOnDeadlySignal);
 425
 426   AllocatorOptions allocator_options;
 427   allocator_options.SetFrom(flags(), common_flags());
 428   InitializeAllocator(allocator_options);
 429
 430   MaybeStartBackgroudThread();
 431   SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
 432
 433   // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
 434   // should be set to 1 prior to initializing the threads.
 435   asan_inited = 1;
 436   asan_init_is_running = false;
 437
 438   if (flags()->atexit)
 439     Atexit(asan_atexit);
 440
 441   InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
 442
 443   // Now that ASan runtime is (mostly) initialized, deactivate it if
 444   // necessary, so that it can be re-activated when requested.
 445   if (flags()->start_deactivated)
 446     AsanDeactivate();
 447
 448   // interceptors
 449   InitTlsSize();
 450
 451   // Create main thread.
 452   AsanThread *main_thread = CreateMainThread();
 453   CHECK_EQ(0, main_thread->tid());
 454   force_interface_symbols();  // no-op.
 455   SanitizerInitializeUnwinder();
 456
 457   if (CAN_SANITIZE_LEAKS) {
 458     __lsan::InitCommonLsan();
 459     if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
 460       if (flags()->halt_on_error)
 461         Atexit(__lsan::DoLeakCheck);
 462       else
 463         Atexit(__lsan::DoRecoverableLeakCheckVoid);
 464     }
 465   }
 466
 467 #if CAN_SANITIZE_UB
 468   __ubsan::InitAsPlugin();
 469 #endif
 470
 471   InitializeSuppressions();
 472
 473   if (CAN_SANITIZE_LEAKS) {
 474     // LateInitialize() calls dlsym, which can allocate an error string buffer
 475     // in the TLS.  Let's ignore the allocation to avoid reporting a leak.
 476     __lsan::ScopedInterceptorDisabler disabler;
 477     Symbolizer::LateInitialize();
 478   } else {
 479     Symbolizer::LateInitialize();
 480   }
 481
 482   VReport(1, "AddressSanitizer Init done\n");
 483
 484   if (flags()->sleep_after_init) {
 485     Report("Sleeping for %d second(s)\n", flags()->sleep_after_init);
 486     SleepForSeconds(flags()->sleep_after_init);
 487   }
 488 }
 489
 490 // Initialize as requested from some part of ASan runtime library (interceptors,
 491 // allocator, etc).
 492 void AsanInitFromRtl() {
 493   AsanInitInternal();
 494 }
 495
 496 #if ASAN_DYNAMIC
 497 // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
 498 // (and thus normal initializers from .preinit_array or modules haven't run).
 499
 500 class AsanInitializer {
 501 public:  // NOLINT
 502   AsanInitializer() {
 503     AsanInitFromRtl();
 504   }
 505 };
 506
 507 static AsanInitializer asan_initializer;
 508 #endif  // ASAN_DYNAMIC
 509
 510 } // namespace __asan
 511
 512 // ---------------------- Interface ---------------- {{{1
 513 using namespace __asan;  // NOLINT
 514
 515 void NOINLINE __asan_handle_no_return() {
 516   if (asan_init_is_running)
 517     return;
 518
 519   int local_stack;
 520   AsanThread *curr_thread = GetCurrentThread();
 521   uptr PageSize = GetPageSizeCached();
 522   uptr top, bottom;
 523   if (curr_thread) {
 524     top = curr_thread->stack_top();
 525     bottom = ((uptr)&local_stack - PageSize) & ~(PageSize - 1);
 526   } else {
 527     CHECK(!SANITIZER_FUCHSIA);
 528     // If we haven't seen this thread, try asking the OS for stack bounds.
 529     uptr tls_addr, tls_size, stack_size;
 530     GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr,
 531                          &tls_size);
 532     top = bottom + stack_size;
 533   }
 534   static const uptr kMaxExpectedCleanupSize = 64 << 20;  // 64M
 535   if (top - bottom > kMaxExpectedCleanupSize) {
 536     static bool reported_warning = false;
 537     if (reported_warning)
 538       return;
 539     reported_warning = true;
 540     Report("WARNING: ASan is ignoring requested __asan_handle_no_return: "
 541            "stack top: %p; bottom %p; size: %p (%zd)\n"
 542            "False positive error reports may follow\n"
 543            "For details see "
 544            "https://github.com/google/sanitizers/issues/189\n",
 545            top, bottom, top - bottom, top - bottom);
 546     return;
 547   }
 548   PoisonShadow(bottom, top - bottom, 0);
 549   if (curr_thread && curr_thread->has_fake_stack())
 550     curr_thread->fake_stack()->HandleNoReturn();
 551 }
 552
 553 void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
 554   SetUserDieCallback(callback);
 555 }
 556
 557 // Initialize as requested from instrumented application code.
 558 // We use this call as a trigger to wake up ASan from deactivated state.
 559 void __asan_init() {
 560   AsanActivate();
 561   AsanInitInternal();
 562 }
 563
 564 void __asan_version_mismatch_check() {
 565   // Do nothing.
 566 }