1 //===-- asan_rtl.cpp ------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file is a part of AddressSanitizer, an address sanity checker.
10 //
11 // Main file of the ASan run-time library.
12 //===----------------------------------------------------------------------===//
13
14 #include "asan_activation.h"
15 #include "asan_allocator.h"
16 #include "asan_interceptors.h"
17 #include "asan_interface_internal.h"
18 #include "asan_internal.h"
19 #include "asan_mapping.h"
20 #include "asan_poisoning.h"
21 #include "asan_report.h"
22 #include "asan_stack.h"
23 #include "asan_stats.h"
24 #include "asan_suppressions.h"
25 #include "asan_thread.h"
26 #include "sanitizer_common/sanitizer_atomic.h"
27 #include "sanitizer_common/sanitizer_flags.h"
28 #include "sanitizer_common/sanitizer_libc.h"
29 #include "sanitizer_common/sanitizer_symbolizer.h"
30 #include "lsan/lsan_common.h"
31 #include "ubsan/ubsan_init.h"
32 #include "ubsan/ubsan_platform.h"
33
34 uptr __asan_shadow_memory_dynamic_address; // Global interface symbol.
35 int __asan_option_detect_stack_use_after_return; // Global interface symbol.
36 uptr *__asan_test_only_reported_buggy_pointer; // Used only for testing asan.
37
38 namespace __asan {
39
40 uptr AsanMappingProfile[kAsanMappingProfileSize];
41
AsanDie()42 static void AsanDie() {
43 static atomic_uint32_t num_calls;
44 if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
45 // Don't die twice - run a busy loop.
46 while (1) { }
47 }
48 if (common_flags()->print_module_map >= 1)
49 DumpProcessMap();
50 if (flags()->sleep_before_dying) {
51 Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
52 SleepForSeconds(flags()->sleep_before_dying);
53 }
54 if (flags()->unmap_shadow_on_exit) {
55 if (kMidMemBeg) {
56 UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
57 UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
58 } else {
59 if (kHighShadowEnd)
60 UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
61 }
62 }
63 }
64
AsanCheckFailed(const char * file,int line,const char * cond,u64 v1,u64 v2)65 static void AsanCheckFailed(const char *file, int line, const char *cond,
66 u64 v1, u64 v2) {
67 Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
68 line, cond, (uptr)v1, (uptr)v2);
69
70 // Print a stack trace the first time we come here. Otherwise, we probably
71 // failed a CHECK during symbolization.
72 static atomic_uint32_t num_calls;
73 if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) == 0) {
74 PRINT_CURRENT_STACK_CHECK();
75 }
76
77 Die();
78 }
79
80 // -------------------------- Globals --------------------- {{{1
81 int asan_inited;
82 bool asan_init_is_running;
83
84 #if !ASAN_FIXED_MAPPING
85 uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
86 #endif
87
88 // -------------------------- Misc ---------------- {{{1
ShowStatsAndAbort()89 void ShowStatsAndAbort() {
90 __asan_print_accumulated_stats();
91 Die();
92 }
93
94 // --------------- LowLevelAllocateCallbac ---------- {{{1
OnLowLevelAllocate(uptr ptr,uptr size)95 static void OnLowLevelAllocate(uptr ptr, uptr size) {
96 PoisonShadow(ptr, size, kAsanInternalHeapMagic);
97 }
98
99 // -------------------------- Run-time entry ------------------- {{{1
100 // exported functions
101 #define ASAN_REPORT_ERROR(type, is_write, size) \
102 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
103 void __asan_report_ ## type ## size(uptr addr) { \
104 GET_CALLER_PC_BP_SP; \
105 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true); \
106 } \
107 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
108 void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) { \
109 GET_CALLER_PC_BP_SP; \
110 ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true); \
111 } \
112 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
113 void __asan_report_ ## type ## size ## _noabort(uptr addr) { \
114 GET_CALLER_PC_BP_SP; \
115 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false); \
116 } \
117
118 ASAN_REPORT_ERROR(load, false, 1)
119 ASAN_REPORT_ERROR(load, false, 2)
120 ASAN_REPORT_ERROR(load, false, 4)
121 ASAN_REPORT_ERROR(load, false, 8)
122 ASAN_REPORT_ERROR(load, false, 16)
123 ASAN_REPORT_ERROR(store, true, 1)
124 ASAN_REPORT_ERROR(store, true, 2)
125 ASAN_REPORT_ERROR(store, true, 4)
126 ASAN_REPORT_ERROR(store, true, 8)
127 ASAN_REPORT_ERROR(store, true, 16)
128
129 #define ASAN_REPORT_ERROR_N(type, is_write) \
130 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
131 void __asan_report_ ## type ## _n(uptr addr, uptr size) { \
132 GET_CALLER_PC_BP_SP; \
133 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true); \
134 } \
135 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
136 void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) { \
137 GET_CALLER_PC_BP_SP; \
138 ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true); \
139 } \
140 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
141 void __asan_report_ ## type ## _n_noabort(uptr addr, uptr size) { \
142 GET_CALLER_PC_BP_SP; \
143 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false); \
144 } \
145
ASAN_REPORT_ERROR_N(load,false)146 ASAN_REPORT_ERROR_N(load, false)
147 ASAN_REPORT_ERROR_N(store, true)
148
149 #define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg, fatal) \
150 if (SANITIZER_MYRIAD2 && !AddrIsInMem(addr) && !AddrIsInShadow(addr)) \
151 return; \
152 uptr sp = MEM_TO_SHADOW(addr); \
153 uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp) \
154 : *reinterpret_cast<u16 *>(sp); \
155 if (UNLIKELY(s)) { \
156 if (UNLIKELY(size >= SHADOW_GRANULARITY || \
157 ((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >= \
158 (s8)s)) { \
159 if (__asan_test_only_reported_buggy_pointer) { \
160 *__asan_test_only_reported_buggy_pointer = addr; \
161 } else { \
162 GET_CALLER_PC_BP_SP; \
163 ReportGenericError(pc, bp, sp, addr, is_write, size, exp_arg, \
164 fatal); \
165 } \
166 } \
167 }
168
169 #define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size) \
170 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
171 void __asan_##type##size(uptr addr) { \
172 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, true) \
173 } \
174 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
175 void __asan_exp_##type##size(uptr addr, u32 exp) { \
176 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp, true) \
177 } \
178 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
179 void __asan_##type##size ## _noabort(uptr addr) { \
180 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, false) \
181 } \
182
183 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
184 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
185 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
186 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
187 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
188 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
189 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
190 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
191 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
192 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
193
194 extern "C"
195 NOINLINE INTERFACE_ATTRIBUTE
196 void __asan_loadN(uptr addr, uptr size) {
197 if (__asan_region_is_poisoned(addr, size)) {
198 GET_CALLER_PC_BP_SP;
199 ReportGenericError(pc, bp, sp, addr, false, size, 0, true);
200 }
201 }
202
203 extern "C"
204 NOINLINE INTERFACE_ATTRIBUTE
__asan_exp_loadN(uptr addr,uptr size,u32 exp)205 void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
206 if (__asan_region_is_poisoned(addr, size)) {
207 GET_CALLER_PC_BP_SP;
208 ReportGenericError(pc, bp, sp, addr, false, size, exp, true);
209 }
210 }
211
212 extern "C"
213 NOINLINE INTERFACE_ATTRIBUTE
__asan_loadN_noabort(uptr addr,uptr size)214 void __asan_loadN_noabort(uptr addr, uptr size) {
215 if (__asan_region_is_poisoned(addr, size)) {
216 GET_CALLER_PC_BP_SP;
217 ReportGenericError(pc, bp, sp, addr, false, size, 0, false);
218 }
219 }
220
221 extern "C"
222 NOINLINE INTERFACE_ATTRIBUTE
__asan_storeN(uptr addr,uptr size)223 void __asan_storeN(uptr addr, uptr size) {
224 if (__asan_region_is_poisoned(addr, size)) {
225 GET_CALLER_PC_BP_SP;
226 ReportGenericError(pc, bp, sp, addr, true, size, 0, true);
227 }
228 }
229
230 extern "C"
231 NOINLINE INTERFACE_ATTRIBUTE
__asan_exp_storeN(uptr addr,uptr size,u32 exp)232 void __asan_exp_storeN(uptr addr, uptr size, u32 exp) {
233 if (__asan_region_is_poisoned(addr, size)) {
234 GET_CALLER_PC_BP_SP;
235 ReportGenericError(pc, bp, sp, addr, true, size, exp, true);
236 }
237 }
238
239 extern "C"
240 NOINLINE INTERFACE_ATTRIBUTE
__asan_storeN_noabort(uptr addr,uptr size)241 void __asan_storeN_noabort(uptr addr, uptr size) {
242 if (__asan_region_is_poisoned(addr, size)) {
243 GET_CALLER_PC_BP_SP;
244 ReportGenericError(pc, bp, sp, addr, true, size, 0, false);
245 }
246 }
247
248 // Force the linker to keep the symbols for various ASan interface functions.
249 // We want to keep those in the executable in order to let the instrumented
250 // dynamic libraries access the symbol even if it is not used by the executable
251 // itself. This should help if the build system is removing dead code at link
252 // time.
force_interface_symbols()253 static NOINLINE void force_interface_symbols() {
254 volatile int fake_condition = 0; // prevent dead condition elimination.
255 // __asan_report_* functions are noreturn, so we need a switch to prevent
256 // the compiler from removing any of them.
257 // clang-format off
258 switch (fake_condition) {
259 case 1: __asan_report_load1(0); break;
260 case 2: __asan_report_load2(0); break;
261 case 3: __asan_report_load4(0); break;
262 case 4: __asan_report_load8(0); break;
263 case 5: __asan_report_load16(0); break;
264 case 6: __asan_report_load_n(0, 0); break;
265 case 7: __asan_report_store1(0); break;
266 case 8: __asan_report_store2(0); break;
267 case 9: __asan_report_store4(0); break;
268 case 10: __asan_report_store8(0); break;
269 case 11: __asan_report_store16(0); break;
270 case 12: __asan_report_store_n(0, 0); break;
271 case 13: __asan_report_exp_load1(0, 0); break;
272 case 14: __asan_report_exp_load2(0, 0); break;
273 case 15: __asan_report_exp_load4(0, 0); break;
274 case 16: __asan_report_exp_load8(0, 0); break;
275 case 17: __asan_report_exp_load16(0, 0); break;
276 case 18: __asan_report_exp_load_n(0, 0, 0); break;
277 case 19: __asan_report_exp_store1(0, 0); break;
278 case 20: __asan_report_exp_store2(0, 0); break;
279 case 21: __asan_report_exp_store4(0, 0); break;
280 case 22: __asan_report_exp_store8(0, 0); break;
281 case 23: __asan_report_exp_store16(0, 0); break;
282 case 24: __asan_report_exp_store_n(0, 0, 0); break;
283 case 25: __asan_register_globals(nullptr, 0); break;
284 case 26: __asan_unregister_globals(nullptr, 0); break;
285 case 27: __asan_set_death_callback(nullptr); break;
286 case 28: __asan_set_error_report_callback(nullptr); break;
287 case 29: __asan_handle_no_return(); break;
288 case 30: __asan_address_is_poisoned(nullptr); break;
289 case 31: __asan_poison_memory_region(nullptr, 0); break;
290 case 32: __asan_unpoison_memory_region(nullptr, 0); break;
291 case 34: __asan_before_dynamic_init(nullptr); break;
292 case 35: __asan_after_dynamic_init(); break;
293 case 36: __asan_poison_stack_memory(0, 0); break;
294 case 37: __asan_unpoison_stack_memory(0, 0); break;
295 case 38: __asan_region_is_poisoned(0, 0); break;
296 case 39: __asan_describe_address(0); break;
297 case 40: __asan_set_shadow_00(0, 0); break;
298 case 41: __asan_set_shadow_f1(0, 0); break;
299 case 42: __asan_set_shadow_f2(0, 0); break;
300 case 43: __asan_set_shadow_f3(0, 0); break;
301 case 44: __asan_set_shadow_f5(0, 0); break;
302 case 45: __asan_set_shadow_f8(0, 0); break;
303 }
304 // clang-format on
305 }
306
asan_atexit()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
InitializeHighMemEnd()317 static void InitializeHighMemEnd() {
318 #if !SANITIZER_MYRIAD2
319 #if !ASAN_FIXED_MAPPING
320 kHighMemEnd = GetMaxUserVirtualAddress();
321 // Increase kHighMemEnd to make sure it's properly
322 // aligned together with kHighMemBeg:
323 kHighMemEnd |= (GetMmapGranularity() << SHADOW_SCALE) - 1;
324 #endif // !ASAN_FIXED_MAPPING
325 CHECK_EQ((kHighMemBeg % GetMmapGranularity()), 0);
326 #endif // !SANITIZER_MYRIAD2
327 }
328
PrintAddressSpaceLayout()329 void PrintAddressSpaceLayout() {
330 if (kHighMemBeg) {
331 Printf("|| `[%p, %p]` || HighMem ||\n",
332 (void*)kHighMemBeg, (void*)kHighMemEnd);
333 Printf("|| `[%p, %p]` || HighShadow ||\n",
334 (void*)kHighShadowBeg, (void*)kHighShadowEnd);
335 }
336 if (kMidMemBeg) {
337 Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
338 (void*)kShadowGap3Beg, (void*)kShadowGap3End);
339 Printf("|| `[%p, %p]` || MidMem ||\n",
340 (void*)kMidMemBeg, (void*)kMidMemEnd);
341 Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
342 (void*)kShadowGap2Beg, (void*)kShadowGap2End);
343 Printf("|| `[%p, %p]` || MidShadow ||\n",
344 (void*)kMidShadowBeg, (void*)kMidShadowEnd);
345 }
346 Printf("|| `[%p, %p]` || ShadowGap ||\n",
347 (void*)kShadowGapBeg, (void*)kShadowGapEnd);
348 if (kLowShadowBeg) {
349 Printf("|| `[%p, %p]` || LowShadow ||\n",
350 (void*)kLowShadowBeg, (void*)kLowShadowEnd);
351 Printf("|| `[%p, %p]` || LowMem ||\n",
352 (void*)kLowMemBeg, (void*)kLowMemEnd);
353 }
354 Printf("MemToShadow(shadow): %p %p",
355 (void*)MEM_TO_SHADOW(kLowShadowBeg),
356 (void*)MEM_TO_SHADOW(kLowShadowEnd));
357 if (kHighMemBeg) {
358 Printf(" %p %p",
359 (void*)MEM_TO_SHADOW(kHighShadowBeg),
360 (void*)MEM_TO_SHADOW(kHighShadowEnd));
361 }
362 if (kMidMemBeg) {
363 Printf(" %p %p",
364 (void*)MEM_TO_SHADOW(kMidShadowBeg),
365 (void*)MEM_TO_SHADOW(kMidShadowEnd));
366 }
367 Printf("\n");
368 Printf("redzone=%zu\n", (uptr)flags()->redzone);
369 Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
370 Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
371 Printf("thread_local_quarantine_size_kb=%zuK\n",
372 (uptr)flags()->thread_local_quarantine_size_kb);
373 Printf("malloc_context_size=%zu\n",
374 (uptr)common_flags()->malloc_context_size);
375
376 Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE);
377 Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY);
378 Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET);
379 CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
380 if (kMidMemBeg)
381 CHECK(kMidShadowBeg > kLowShadowEnd &&
382 kMidMemBeg > kMidShadowEnd &&
383 kHighShadowBeg > kMidMemEnd);
384 }
385
386 #if defined(__thumb__) && defined(__linux__)
387 #define START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
388 #endif
389
390 #ifndef START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
__anon5b305cd90102null391 static bool UNUSED __local_asan_dyninit = [] {
392 MaybeStartBackgroudThread();
393 SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
394
395 return false;
396 }();
397 #endif
398
AsanInitInternal()399 static void AsanInitInternal() {
400 if (LIKELY(asan_inited)) return;
401 SanitizerToolName = "AddressSanitizer";
402 CHECK(!asan_init_is_running && "ASan init calls itself!");
403 asan_init_is_running = true;
404
405 CacheBinaryName();
406
407 // Initialize flags. This must be done early, because most of the
408 // initialization steps look at flags().
409 InitializeFlags();
410
411 // Stop performing init at this point if we are being loaded via
412 // dlopen() and the platform supports it.
413 if (SANITIZER_SUPPORTS_INIT_FOR_DLOPEN && UNLIKELY(HandleDlopenInit())) {
414 asan_init_is_running = false;
415 VReport(1, "AddressSanitizer init is being performed for dlopen().\n");
416 return;
417 }
418
419 AsanCheckIncompatibleRT();
420 AsanCheckDynamicRTPrereqs();
421 AvoidCVE_2016_2143();
422
423 SetCanPoisonMemory(flags()->poison_heap);
424 SetMallocContextSize(common_flags()->malloc_context_size);
425
426 InitializePlatformExceptionHandlers();
427
428 InitializeHighMemEnd();
429
430 // Make sure we are not statically linked.
431 AsanDoesNotSupportStaticLinkage();
432
433 // Install tool-specific callbacks in sanitizer_common.
434 AddDieCallback(AsanDie);
435 SetCheckFailedCallback(AsanCheckFailed);
436 SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
437
438 __sanitizer_set_report_path(common_flags()->log_path);
439
440 __asan_option_detect_stack_use_after_return =
441 flags()->detect_stack_use_after_return;
442
443 __sanitizer::InitializePlatformEarly();
444
445 // Re-exec ourselves if we need to set additional env or command line args.
446 MaybeReexec();
447
448 // Setup internal allocator callback.
449 SetLowLevelAllocateMinAlignment(SHADOW_GRANULARITY);
450 SetLowLevelAllocateCallback(OnLowLevelAllocate);
451
452 InitializeAsanInterceptors();
453 CheckASLR();
454
455 // Enable system log ("adb logcat") on Android.
456 // Doing this before interceptors are initialized crashes in:
457 // AsanInitInternal -> android_log_write -> __interceptor_strcmp
458 AndroidLogInit();
459
460 ReplaceSystemMalloc();
461
462 DisableCoreDumperIfNecessary();
463
464 InitializeShadowMemory();
465
466 AsanTSDInit(PlatformTSDDtor);
467 InstallDeadlySignalHandlers(AsanOnDeadlySignal);
468
469 AllocatorOptions allocator_options;
470 allocator_options.SetFrom(flags(), common_flags());
471 InitializeAllocator(allocator_options);
472
473 #ifdef START_BACKGROUND_THREAD_IN_ASAN_INTERNAL
474 MaybeStartBackgroudThread();
475 SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
476 #endif
477
478 // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
479 // should be set to 1 prior to initializing the threads.
480 asan_inited = 1;
481 asan_init_is_running = false;
482
483 if (flags()->atexit)
484 Atexit(asan_atexit);
485
486 InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
487
488 // Now that ASan runtime is (mostly) initialized, deactivate it if
489 // necessary, so that it can be re-activated when requested.
490 if (flags()->start_deactivated)
491 AsanDeactivate();
492
493 // interceptors
494 InitTlsSize();
495
496 // Create main thread.
497 AsanThread *main_thread = CreateMainThread();
498 CHECK_EQ(0, main_thread->tid());
499 force_interface_symbols(); // no-op.
500 SanitizerInitializeUnwinder();
501
502 if (CAN_SANITIZE_LEAKS) {
503 __lsan::InitCommonLsan();
504 if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
505 if (flags()->halt_on_error)
506 Atexit(__lsan::DoLeakCheck);
507 else
508 Atexit(__lsan::DoRecoverableLeakCheckVoid);
509 }
510 }
511
512 #if CAN_SANITIZE_UB
513 __ubsan::InitAsPlugin();
514 #endif
515
516 InitializeSuppressions();
517
518 if (CAN_SANITIZE_LEAKS) {
519 // LateInitialize() calls dlsym, which can allocate an error string buffer
520 // in the TLS. Let's ignore the allocation to avoid reporting a leak.
521 __lsan::ScopedInterceptorDisabler disabler;
522 Symbolizer::LateInitialize();
523 } else {
524 Symbolizer::LateInitialize();
525 }
526
527 VReport(1, "AddressSanitizer Init done\n");
528
529 if (flags()->sleep_after_init) {
530 Report("Sleeping for %d second(s)\n", flags()->sleep_after_init);
531 SleepForSeconds(flags()->sleep_after_init);
532 }
533 }
534
535 // Initialize as requested from some part of ASan runtime library (interceptors,
536 // allocator, etc).
AsanInitFromRtl()537 void AsanInitFromRtl() {
538 AsanInitInternal();
539 }
540
541 #if ASAN_DYNAMIC
542 // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
543 // (and thus normal initializers from .preinit_array or modules haven't run).
544
545 class AsanInitializer {
546 public:
AsanInitializer()547 AsanInitializer() {
548 AsanInitFromRtl();
549 }
550 };
551
552 static AsanInitializer asan_initializer;
553 #endif // ASAN_DYNAMIC
554
UnpoisonStack(uptr bottom,uptr top,const char * type)555 void UnpoisonStack(uptr bottom, uptr top, const char *type) {
556 static const uptr kMaxExpectedCleanupSize = 64 << 20; // 64M
557 if (top - bottom > kMaxExpectedCleanupSize) {
558 static bool reported_warning = false;
559 if (reported_warning)
560 return;
561 reported_warning = true;
562 Report(
563 "WARNING: ASan is ignoring requested __asan_handle_no_return: "
564 "stack type: %s top: %p; bottom %p; size: %p (%zd)\n"
565 "False positive error reports may follow\n"
566 "For details see "
567 "https://github.com/google/sanitizers/issues/189\n",
568 type, top, bottom, top - bottom, top - bottom);
569 return;
570 }
571 PoisonShadow(bottom, top - bottom, 0);
572 }
573
UnpoisonDefaultStack()574 static void UnpoisonDefaultStack() {
575 uptr bottom, top;
576
577 if (AsanThread *curr_thread = GetCurrentThread()) {
578 int local_stack;
579 const uptr page_size = GetPageSizeCached();
580 top = curr_thread->stack_top();
581 bottom = ((uptr)&local_stack - page_size) & ~(page_size - 1);
582 } else if (SANITIZER_RTEMS) {
583 // Give up On RTEMS.
584 return;
585 } else {
586 CHECK(!SANITIZER_FUCHSIA);
587 // If we haven't seen this thread, try asking the OS for stack bounds.
588 uptr tls_addr, tls_size, stack_size;
589 GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr,
590 &tls_size);
591 top = bottom + stack_size;
592 }
593
594 UnpoisonStack(bottom, top, "default");
595 }
596
UnpoisonFakeStack()597 static void UnpoisonFakeStack() {
598 AsanThread *curr_thread = GetCurrentThread();
599 if (curr_thread && curr_thread->has_fake_stack())
600 curr_thread->fake_stack()->HandleNoReturn();
601 }
602
603 } // namespace __asan
604
605 // ---------------------- Interface ---------------- {{{1
606 using namespace __asan;
607
__asan_handle_no_return()608 void NOINLINE __asan_handle_no_return() {
609 if (asan_init_is_running)
610 return;
611
612 if (!PlatformUnpoisonStacks())
613 UnpoisonDefaultStack();
614
615 UnpoisonFakeStack();
616 }
617
__asan_extra_spill_area()618 extern "C" void *__asan_extra_spill_area() {
619 AsanThread *t = GetCurrentThread();
620 CHECK(t);
621 return t->extra_spill_area();
622 }
623
__asan_handle_vfork(void * sp)624 void __asan_handle_vfork(void *sp) {
625 AsanThread *t = GetCurrentThread();
626 CHECK(t);
627 uptr bottom = t->stack_bottom();
628 PoisonShadow(bottom, (uptr)sp - bottom, 0);
629 }
630
__asan_set_death_callback(void (* callback)(void))631 void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
632 SetUserDieCallback(callback);
633 }
634
635 // Initialize as requested from instrumented application code.
636 // We use this call as a trigger to wake up ASan from deactivated state.
__asan_init()637 void __asan_init() {
638 AsanActivate();
639 AsanInitInternal();
640 }
641
__asan_version_mismatch_check()642 void __asan_version_mismatch_check() {
643 // Do nothing.
644 }
645