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 } 622