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