asan_rtl.cpp revision 360784 
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
34uptr __asan_shadow_memory_dynamic_address;  // Global interface symbol.
35int __asan_option_detect_stack_use_after_return;  // Global interface symbol.
36uptr *__asan_test_only_reported_buggy_pointer;  // Used only for testing asan.
37
38namespace __asan {
39
40uptr AsanMappingProfile[kAsanMappingProfileSize];
41
42static 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) PrintModuleMap();
49  if (flags()->sleep_before_dying) {
50    Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
51    SleepForSeconds(flags()->sleep_before_dying);
52  }
53  if (flags()->unmap_shadow_on_exit) {
54    if (kMidMemBeg) {
55      UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
56      UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
57    } else {
58      if (kHighShadowEnd)
59        UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
60    }
61  }
62}
63
64static void AsanCheckFailed(const char *file, int line, const char *cond,
65                            u64 v1, u64 v2) {
66  Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
67         line, cond, (uptr)v1, (uptr)v2);
68
69  // Print a stack trace the first time we come here. Otherwise, we probably
70  // failed a CHECK during symbolization.
71  static atomic_uint32_t num_calls;
72  if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) == 0) {
73    PRINT_CURRENT_STACK_CHECK();
74  }
75
76  Die();
77}
78
79// -------------------------- Globals --------------------- {{{1
80int asan_inited;
81bool asan_init_is_running;
82
83#if !ASAN_FIXED_MAPPING
84uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
85#endif
86
87// -------------------------- Misc ---------------- {{{1
88void ShowStatsAndAbort() {
89  __asan_print_accumulated_stats();
90  Die();
91}
92
93// --------------- LowLevelAllocateCallbac ---------- {{{1
94static void OnLowLevelAllocate(uptr ptr, uptr size) {
95  PoisonShadow(ptr, size, kAsanInternalHeapMagic);
96}
97
98// -------------------------- Run-time entry ------------------- {{{1
99// exported functions
100#define ASAN_REPORT_ERROR(type, is_write, size)                     \
101extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
102void __asan_report_ ## type ## size(uptr addr) {                    \
103  GET_CALLER_PC_BP_SP;                                              \
104  ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);    \
105}                                                                   \
106extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
107void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) {       \
108  GET_CALLER_PC_BP_SP;                                              \
109  ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);  \
110}                                                                   \
111extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
112void __asan_report_ ## type ## size ## _noabort(uptr addr) {        \
113  GET_CALLER_PC_BP_SP;                                              \
114  ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);   \
115}                                                                   \
116
117ASAN_REPORT_ERROR(load, false, 1)
118ASAN_REPORT_ERROR(load, false, 2)
119ASAN_REPORT_ERROR(load, false, 4)
120ASAN_REPORT_ERROR(load, false, 8)
121ASAN_REPORT_ERROR(load, false, 16)
122ASAN_REPORT_ERROR(store, true, 1)
123ASAN_REPORT_ERROR(store, true, 2)
124ASAN_REPORT_ERROR(store, true, 4)
125ASAN_REPORT_ERROR(store, true, 8)
126ASAN_REPORT_ERROR(store, true, 16)
127
128#define ASAN_REPORT_ERROR_N(type, is_write)                                 \
129extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
130void __asan_report_ ## type ## _n(uptr addr, uptr size) {                   \
131  GET_CALLER_PC_BP_SP;                                                      \
132  ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true);            \
133}                                                                           \
134extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
135void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) {      \
136  GET_CALLER_PC_BP_SP;                                                      \
137  ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true);          \
138}                                                                           \
139extern "C" NOINLINE INTERFACE_ATTRIBUTE                                     \
140void __asan_report_ ## type ## _n_noabort(uptr addr, uptr size) {           \
141  GET_CALLER_PC_BP_SP;                                                      \
142  ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false);           \
143}                                                                           \
144
145ASAN_REPORT_ERROR_N(load, false)
146ASAN_REPORT_ERROR_N(store, true)
147
148#define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg, fatal) \
149    if (SANITIZER_MYRIAD2 && !AddrIsInMem(addr) && !AddrIsInShadow(addr))      \
150      return;                                                                  \
151    uptr sp = MEM_TO_SHADOW(addr);                                             \
152    uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp)          \
153                                        : *reinterpret_cast<u16 *>(sp);        \
154    if (UNLIKELY(s)) {                                                         \
155      if (UNLIKELY(size >= SHADOW_GRANULARITY ||                               \
156                   ((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >=     \
157                       (s8)s)) {                                               \
158        if (__asan_test_only_reported_buggy_pointer) {                         \
159          *__asan_test_only_reported_buggy_pointer = addr;                     \
160        } else {                                                               \
161          GET_CALLER_PC_BP_SP;                                                 \
162          ReportGenericError(pc, bp, sp, addr, is_write, size, exp_arg,        \
163                              fatal);                                          \
164        }                                                                      \
165      }                                                                        \
166    }
167
168#define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size)                      \
169  extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
170  void __asan_##type##size(uptr addr) {                                        \
171    ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, true)            \
172  }                                                                            \
173  extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
174  void __asan_exp_##type##size(uptr addr, u32 exp) {                           \
175    ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp, true)          \
176  }                                                                            \
177  extern "C" NOINLINE INTERFACE_ATTRIBUTE                                      \
178  void __asan_##type##size ## _noabort(uptr addr) {                            \
179    ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, false)           \
180  }                                                                            \
181
182ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
183ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
184ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
185ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
186ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
187ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
188ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
189ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
190ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
191ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
192
193extern "C"
194NOINLINE INTERFACE_ATTRIBUTE
195void __asan_loadN(uptr addr, uptr size) {
196  if (__asan_region_is_poisoned(addr, size)) {
197    GET_CALLER_PC_BP_SP;
198    ReportGenericError(pc, bp, sp, addr, false, size, 0, true);
199  }
200}
201
202extern "C"
203NOINLINE INTERFACE_ATTRIBUTE
204void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
205  if (__asan_region_is_poisoned(addr, size)) {
206    GET_CALLER_PC_BP_SP;
207    ReportGenericError(pc, bp, sp, addr, false, size, exp, true);
208  }
209}
210
211extern "C"
212NOINLINE INTERFACE_ATTRIBUTE
213void __asan_loadN_noabort(uptr addr, uptr size) {
214  if (__asan_region_is_poisoned(addr, size)) {
215    GET_CALLER_PC_BP_SP;
216    ReportGenericError(pc, bp, sp, addr, false, size, 0, false);
217  }
218}
219
220extern "C"
221NOINLINE INTERFACE_ATTRIBUTE
222void __asan_storeN(uptr addr, uptr size) {
223  if (__asan_region_is_poisoned(addr, size)) {
224    GET_CALLER_PC_BP_SP;
225    ReportGenericError(pc, bp, sp, addr, true, size, 0, true);
226  }
227}
228
229extern "C"
230NOINLINE INTERFACE_ATTRIBUTE
231void __asan_exp_storeN(uptr addr, uptr size, u32 exp) {
232  if (__asan_region_is_poisoned(addr, size)) {
233    GET_CALLER_PC_BP_SP;
234    ReportGenericError(pc, bp, sp, addr, true, size, exp, true);
235  }
236}
237
238extern "C"
239NOINLINE INTERFACE_ATTRIBUTE
240void __asan_storeN_noabort(uptr addr, uptr size) {
241  if (__asan_region_is_poisoned(addr, size)) {
242    GET_CALLER_PC_BP_SP;
243    ReportGenericError(pc, bp, sp, addr, true, size, 0, false);
244  }
245}
246
247// Force the linker to keep the symbols for various ASan interface functions.
248// We want to keep those in the executable in order to let the instrumented
249// dynamic libraries access the symbol even if it is not used by the executable
250// itself. This should help if the build system is removing dead code at link
251// time.
252static NOINLINE void force_interface_symbols() {
253  volatile int fake_condition = 0;  // prevent dead condition elimination.
254  // __asan_report_* functions are noreturn, so we need a switch to prevent
255  // the compiler from removing any of them.
256  // clang-format off
257  switch (fake_condition) {
258    case 1: __asan_report_load1(0); break;
259    case 2: __asan_report_load2(0); break;
260    case 3: __asan_report_load4(0); break;
261    case 4: __asan_report_load8(0); break;
262    case 5: __asan_report_load16(0); break;
263    case 6: __asan_report_load_n(0, 0); break;
264    case 7: __asan_report_store1(0); break;
265    case 8: __asan_report_store2(0); break;
266    case 9: __asan_report_store4(0); break;
267    case 10: __asan_report_store8(0); break;
268    case 11: __asan_report_store16(0); break;
269    case 12: __asan_report_store_n(0, 0); break;
270    case 13: __asan_report_exp_load1(0, 0); break;
271    case 14: __asan_report_exp_load2(0, 0); break;
272    case 15: __asan_report_exp_load4(0, 0); break;
273    case 16: __asan_report_exp_load8(0, 0); break;
274    case 17: __asan_report_exp_load16(0, 0); break;
275    case 18: __asan_report_exp_load_n(0, 0, 0); break;
276    case 19: __asan_report_exp_store1(0, 0); break;
277    case 20: __asan_report_exp_store2(0, 0); break;
278    case 21: __asan_report_exp_store4(0, 0); break;
279    case 22: __asan_report_exp_store8(0, 0); break;
280    case 23: __asan_report_exp_store16(0, 0); break;
281    case 24: __asan_report_exp_store_n(0, 0, 0); break;
282    case 25: __asan_register_globals(nullptr, 0); break;
283    case 26: __asan_unregister_globals(nullptr, 0); break;
284    case 27: __asan_set_death_callback(nullptr); break;
285    case 28: __asan_set_error_report_callback(nullptr); break;
286    case 29: __asan_handle_no_return(); break;
287    case 30: __asan_address_is_poisoned(nullptr); break;
288    case 31: __asan_poison_memory_region(nullptr, 0); break;
289    case 32: __asan_unpoison_memory_region(nullptr, 0); break;
290    case 34: __asan_before_dynamic_init(nullptr); break;
291    case 35: __asan_after_dynamic_init(); break;
292    case 36: __asan_poison_stack_memory(0, 0); break;
293    case 37: __asan_unpoison_stack_memory(0, 0); break;
294    case 38: __asan_region_is_poisoned(0, 0); break;
295    case 39: __asan_describe_address(0); break;
296    case 40: __asan_set_shadow_00(0, 0); break;
297    case 41: __asan_set_shadow_f1(0, 0); break;
298    case 42: __asan_set_shadow_f2(0, 0); break;
299    case 43: __asan_set_shadow_f3(0, 0); break;
300    case 44: __asan_set_shadow_f5(0, 0); break;
301    case 45: __asan_set_shadow_f8(0, 0); break;
302  }
303  // clang-format on
304}
305
306static void asan_atexit() {
307  Printf("AddressSanitizer exit stats:\n");
308  __asan_print_accumulated_stats();
309  // Print AsanMappingProfile.
310  for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
311    if (AsanMappingProfile[i] == 0) continue;
312    Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
313  }
314}
315
316static void InitializeHighMemEnd() {
317#if !SANITIZER_MYRIAD2
318#if !ASAN_FIXED_MAPPING
319  kHighMemEnd = GetMaxUserVirtualAddress();
320  // Increase kHighMemEnd to make sure it's properly
321  // aligned together with kHighMemBeg:
322  kHighMemEnd |= SHADOW_GRANULARITY * GetMmapGranularity() - 1;
323#endif  // !ASAN_FIXED_MAPPING
324  CHECK_EQ((kHighMemBeg % GetMmapGranularity()), 0);
325#endif  // !SANITIZER_MYRIAD2
326}
327
328void PrintAddressSpaceLayout() {
329  if (kHighMemBeg) {
330    Printf("|| `[%p, %p]` || HighMem    ||\n",
331           (void*)kHighMemBeg, (void*)kHighMemEnd);
332    Printf("|| `[%p, %p]` || HighShadow ||\n",
333           (void*)kHighShadowBeg, (void*)kHighShadowEnd);
334  }
335  if (kMidMemBeg) {
336    Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
337           (void*)kShadowGap3Beg, (void*)kShadowGap3End);
338    Printf("|| `[%p, %p]` || MidMem     ||\n",
339           (void*)kMidMemBeg, (void*)kMidMemEnd);
340    Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
341           (void*)kShadowGap2Beg, (void*)kShadowGap2End);
342    Printf("|| `[%p, %p]` || MidShadow  ||\n",
343           (void*)kMidShadowBeg, (void*)kMidShadowEnd);
344  }
345  Printf("|| `[%p, %p]` || ShadowGap  ||\n",
346         (void*)kShadowGapBeg, (void*)kShadowGapEnd);
347  if (kLowShadowBeg) {
348    Printf("|| `[%p, %p]` || LowShadow  ||\n",
349           (void*)kLowShadowBeg, (void*)kLowShadowEnd);
350    Printf("|| `[%p, %p]` || LowMem     ||\n",
351           (void*)kLowMemBeg, (void*)kLowMemEnd);
352  }
353  Printf("MemToShadow(shadow): %p %p",
354         (void*)MEM_TO_SHADOW(kLowShadowBeg),
355         (void*)MEM_TO_SHADOW(kLowShadowEnd));
356  if (kHighMemBeg) {
357    Printf(" %p %p",
358           (void*)MEM_TO_SHADOW(kHighShadowBeg),
359           (void*)MEM_TO_SHADOW(kHighShadowEnd));
360  }
361  if (kMidMemBeg) {
362    Printf(" %p %p",
363           (void*)MEM_TO_SHADOW(kMidShadowBeg),
364           (void*)MEM_TO_SHADOW(kMidShadowEnd));
365  }
366  Printf("\n");
367  Printf("redzone=%zu\n", (uptr)flags()->redzone);
368  Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
369  Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
370  Printf("thread_local_quarantine_size_kb=%zuK\n",
371         (uptr)flags()->thread_local_quarantine_size_kb);
372  Printf("malloc_context_size=%zu\n",
373         (uptr)common_flags()->malloc_context_size);
374
375  Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE);
376  Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY);
377  Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET);
378  CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
379  if (kMidMemBeg)
380    CHECK(kMidShadowBeg > kLowShadowEnd &&
381          kMidMemBeg > kMidShadowEnd &&
382          kHighShadowBeg > kMidMemEnd);
383}
384
385#if defined(__thumb__) && defined(__linux__)
386#define START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
387#endif
388
389#ifndef START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
390static bool UNUSED __local_asan_dyninit = [] {
391  MaybeStartBackgroudThread();
392  SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
393
394  return false;
395}();
396#endif
397
398static void AsanInitInternal() {
399  if (LIKELY(asan_inited)) return;
400  SanitizerToolName = "AddressSanitizer";
401  CHECK(!asan_init_is_running && "ASan init calls itself!");
402  asan_init_is_running = true;
403
404  CacheBinaryName();
405
406  // Initialize flags. This must be done early, because most of the
407  // initialization steps look at flags().
408  InitializeFlags();
409
410  // Stop performing init at this point if we are being loaded via
411  // dlopen() and the platform supports it.
412  if (SANITIZER_SUPPORTS_INIT_FOR_DLOPEN && UNLIKELY(HandleDlopenInit())) {
413    asan_init_is_running = false;
414    VReport(1, "AddressSanitizer init is being performed for dlopen().\n");
415    return;
416  }
417
418  AsanCheckIncompatibleRT();
419  AsanCheckDynamicRTPrereqs();
420  AvoidCVE_2016_2143();
421
422  SetCanPoisonMemory(flags()->poison_heap);
423  SetMallocContextSize(common_flags()->malloc_context_size);
424
425  InitializePlatformExceptionHandlers();
426
427  InitializeHighMemEnd();
428
429  // Make sure we are not statically linked.
430  AsanDoesNotSupportStaticLinkage();
431
432  // Install tool-specific callbacks in sanitizer_common.
433  AddDieCallback(AsanDie);
434  SetCheckFailedCallback(AsanCheckFailed);
435  SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
436
437  __sanitizer_set_report_path(common_flags()->log_path);
438
439  __asan_option_detect_stack_use_after_return =
440      flags()->detect_stack_use_after_return;
441
442  __sanitizer::InitializePlatformEarly();
443
444  // Re-exec ourselves if we need to set additional env or command line args.
445  MaybeReexec();
446
447  // Setup internal allocator callback.
448  SetLowLevelAllocateMinAlignment(SHADOW_GRANULARITY);
449  SetLowLevelAllocateCallback(OnLowLevelAllocate);
450
451  InitializeAsanInterceptors();
452  CheckASLR();
453
454  // Enable system log ("adb logcat") on Android.
455  // Doing this before interceptors are initialized crashes in:
456  // AsanInitInternal -> android_log_write -> __interceptor_strcmp
457  AndroidLogInit();
458
459  ReplaceSystemMalloc();
460
461  DisableCoreDumperIfNecessary();
462
463  InitializeShadowMemory();
464
465  AsanTSDInit(PlatformTSDDtor);
466  InstallDeadlySignalHandlers(AsanOnDeadlySignal);
467
468  AllocatorOptions allocator_options;
469  allocator_options.SetFrom(flags(), common_flags());
470  InitializeAllocator(allocator_options);
471
472#ifdef START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
473  MaybeStartBackgroudThread();
474  SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
475#endif
476
477  // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
478  // should be set to 1 prior to initializing the threads.
479  asan_inited = 1;
480  asan_init_is_running = false;
481
482  if (flags()->atexit)
483    Atexit(asan_atexit);
484
485  InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
486
487  // Now that ASan runtime is (mostly) initialized, deactivate it if
488  // necessary, so that it can be re-activated when requested.
489  if (flags()->start_deactivated)
490    AsanDeactivate();
491
492  // interceptors
493  InitTlsSize();
494
495  // Create main thread.
496  AsanThread *main_thread = CreateMainThread();
497  CHECK_EQ(0, main_thread->tid());
498  force_interface_symbols();  // no-op.
499  SanitizerInitializeUnwinder();
500
501  if (CAN_SANITIZE_LEAKS) {
502    __lsan::InitCommonLsan();
503    if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
504      if (flags()->halt_on_error)
505        Atexit(__lsan::DoLeakCheck);
506      else
507        Atexit(__lsan::DoRecoverableLeakCheckVoid);
508    }
509  }
510
511#if CAN_SANITIZE_UB
512  __ubsan::InitAsPlugin();
513#endif
514
515  InitializeSuppressions();
516
517  if (CAN_SANITIZE_LEAKS) {
518    // LateInitialize() calls dlsym, which can allocate an error string buffer
519    // in the TLS.  Let's ignore the allocation to avoid reporting a leak.
520    __lsan::ScopedInterceptorDisabler disabler;
521    Symbolizer::LateInitialize();
522  } else {
523    Symbolizer::LateInitialize();
524  }
525
526  VReport(1, "AddressSanitizer Init done\n");
527
528  if (flags()->sleep_after_init) {
529    Report("Sleeping for %d second(s)\n", flags()->sleep_after_init);
530    SleepForSeconds(flags()->sleep_after_init);
531  }
532}
533
534// Initialize as requested from some part of ASan runtime library (interceptors,
535// allocator, etc).
536void AsanInitFromRtl() {
537  AsanInitInternal();
538}
539
540#if ASAN_DYNAMIC
541// Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
542// (and thus normal initializers from .preinit_array or modules haven't run).
543
544class AsanInitializer {
545 public:
546  AsanInitializer() {
547    AsanInitFromRtl();
548  }
549};
550
551static AsanInitializer asan_initializer;
552#endif  // ASAN_DYNAMIC
553
554} // namespace __asan
555
556// ---------------------- Interface ---------------- {{{1
557using namespace __asan;
558
559void NOINLINE __asan_handle_no_return() {
560  if (asan_init_is_running)
561    return;
562
563  int local_stack;
564  AsanThread *curr_thread = GetCurrentThread();
565  uptr PageSize = GetPageSizeCached();
566  uptr top, bottom;
567  if (curr_thread) {
568    top = curr_thread->stack_top();
569    bottom = ((uptr)&local_stack - PageSize) & ~(PageSize - 1);
570  } else if (SANITIZER_RTEMS) {
571    // Give up On RTEMS.
572    return;
573  } else {
574    CHECK(!SANITIZER_FUCHSIA);
575    // If we haven't seen this thread, try asking the OS for stack bounds.
576    uptr tls_addr, tls_size, stack_size;
577    GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr,
578                         &tls_size);
579    top = bottom + stack_size;
580  }
581  static const uptr kMaxExpectedCleanupSize = 64 << 20;  // 64M
582  if (top - bottom > kMaxExpectedCleanupSize) {
583    static bool reported_warning = false;
584    if (reported_warning)
585      return;
586    reported_warning = true;
587    Report("WARNING: ASan is ignoring requested __asan_handle_no_return: "
588           "stack top: %p; bottom %p; size: %p (%zd)\n"
589           "False positive error reports may follow\n"
590           "For details see "
591           "https://github.com/google/sanitizers/issues/189\n",
592           top, bottom, top - bottom, top - bottom);
593    return;
594  }
595  PoisonShadow(bottom, top - bottom, 0);
596  if (curr_thread && curr_thread->has_fake_stack())
597    curr_thread->fake_stack()->HandleNoReturn();
598}
599
600extern "C" void *__asan_extra_spill_area() {
601  AsanThread *t = GetCurrentThread();
602  CHECK(t);
603  return t->extra_spill_area();
604}
605
606void __asan_handle_vfork(void *sp) {
607  AsanThread *t = GetCurrentThread();
608  CHECK(t);
609  uptr bottom = t->stack_bottom();
610  PoisonShadow(bottom, (uptr)sp - bottom, 0);
611}
612
613void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
614  SetUserDieCallback(callback);
615}
616
617// Initialize as requested from instrumented application code.
618// We use this call as a trigger to wake up ASan from deactivated state.
619void __asan_init() {
620  AsanActivate();
621  AsanInitInternal();
622}
623
624void __asan_version_mismatch_check() {
625  // Do nothing.
626}
627