1 //===-- asan_rtl.cc -------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file is a part of AddressSanitizer, an address sanity checker.
11 //
12 // Main file of the ASan run-time library.
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 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
AsanDie()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 (flags()->sleep_before_dying) {
48 Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
49 SleepForSeconds(flags()->sleep_before_dying);
50 }
51 if (flags()->unmap_shadow_on_exit) {
52 if (kMidMemBeg) {
53 UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
54 UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
55 } else {
56 UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
57 }
58 }
59 if (common_flags()->coverage)
60 __sanitizer_cov_dump();
61 if (flags()->abort_on_error)
62 Abort();
63 internal__exit(flags()->exitcode);
64 }
65
AsanCheckFailed(const char * file,int line,const char * cond,u64 v1,u64 v2)66 static void AsanCheckFailed(const char *file, int line, const char *cond,
67 u64 v1, u64 v2) {
68 Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
69 line, cond, (uptr)v1, (uptr)v2);
70 // FIXME: check for infinite recursion without a thread-local counter here.
71 PRINT_CURRENT_STACK_CHECK();
72 Die();
73 }
74
75 // -------------------------- Globals --------------------- {{{1
76 int asan_inited;
77 bool asan_init_is_running;
78
79 #if !ASAN_FIXED_MAPPING
80 uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
81 #endif
82
83 // -------------------------- Misc ---------------- {{{1
ShowStatsAndAbort()84 void ShowStatsAndAbort() {
85 __asan_print_accumulated_stats();
86 Die();
87 }
88
89 // ---------------------- mmap -------------------- {{{1
90 // Reserve memory range [beg, end].
91 // We need to use inclusive range because end+1 may not be representable.
ReserveShadowMemoryRange(uptr beg,uptr end)92 void ReserveShadowMemoryRange(uptr beg, uptr end) {
93 CHECK_EQ((beg % GetPageSizeCached()), 0);
94 CHECK_EQ(((end + 1) % GetPageSizeCached()), 0);
95 uptr size = end - beg + 1;
96 DecreaseTotalMmap(size); // Don't count the shadow against mmap_limit_mb.
97 void *res = MmapFixedNoReserve(beg, size);
98 if (res != (void*)beg) {
99 Report("ReserveShadowMemoryRange failed while trying to map 0x%zx bytes. "
100 "Perhaps you're using ulimit -v\n", size);
101 Abort();
102 }
103 if (common_flags()->no_huge_pages_for_shadow)
104 NoHugePagesInRegion(beg, size);
105 if (common_flags()->use_madv_dontdump)
106 DontDumpShadowMemory(beg, size);
107 }
108
109 // --------------- LowLevelAllocateCallbac ---------- {{{1
OnLowLevelAllocate(uptr ptr,uptr size)110 static void OnLowLevelAllocate(uptr ptr, uptr size) {
111 PoisonShadow(ptr, size, kAsanInternalHeapMagic);
112 }
113
114 // -------------------------- Run-time entry ------------------- {{{1
115 // exported functions
116 #define ASAN_REPORT_ERROR(type, is_write, size) \
117 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
118 void __asan_report_ ## type ## size(uptr addr) { \
119 GET_CALLER_PC_BP_SP; \
120 __asan_report_error(pc, bp, sp, addr, is_write, size, 0); \
121 } \
122 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
123 void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) { \
124 GET_CALLER_PC_BP_SP; \
125 __asan_report_error(pc, bp, sp, addr, is_write, size, exp); \
126 }
127
128 ASAN_REPORT_ERROR(load, false, 1)
129 ASAN_REPORT_ERROR(load, false, 2)
130 ASAN_REPORT_ERROR(load, false, 4)
131 ASAN_REPORT_ERROR(load, false, 8)
132 ASAN_REPORT_ERROR(load, false, 16)
133 ASAN_REPORT_ERROR(store, true, 1)
134 ASAN_REPORT_ERROR(store, true, 2)
135 ASAN_REPORT_ERROR(store, true, 4)
136 ASAN_REPORT_ERROR(store, true, 8)
137 ASAN_REPORT_ERROR(store, true, 16)
138
139 #define ASAN_REPORT_ERROR_N(type, is_write) \
140 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
141 void __asan_report_ ## type ## _n(uptr addr, uptr size) { \
142 GET_CALLER_PC_BP_SP; \
143 __asan_report_error(pc, bp, sp, addr, is_write, size, 0); \
144 } \
145 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
146 void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) { \
147 GET_CALLER_PC_BP_SP; \
148 __asan_report_error(pc, bp, sp, addr, is_write, size, exp); \
149 }
150
ASAN_REPORT_ERROR_N(load,false)151 ASAN_REPORT_ERROR_N(load, false)
152 ASAN_REPORT_ERROR_N(store, true)
153
154 #define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg) \
155 uptr sp = MEM_TO_SHADOW(addr); \
156 uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp) \
157 : *reinterpret_cast<u16 *>(sp); \
158 if (UNLIKELY(s)) { \
159 if (UNLIKELY(size >= SHADOW_GRANULARITY || \
160 ((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >= \
161 (s8)s)) { \
162 if (__asan_test_only_reported_buggy_pointer) { \
163 *__asan_test_only_reported_buggy_pointer = addr; \
164 } else { \
165 GET_CALLER_PC_BP_SP; \
166 __asan_report_error(pc, bp, sp, addr, is_write, size, exp_arg); \
167 } \
168 } \
169 }
170
171 #define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size) \
172 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
173 void __asan_##type##size(uptr addr) { \
174 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0) \
175 } \
176 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
177 void __asan_exp_##type##size(uptr addr, u32 exp) { \
178 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp) \
179 }
180
181 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
182 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
183 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
184 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
185 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
186 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
187 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
188 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
189 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
190 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
191
192 extern "C"
193 NOINLINE INTERFACE_ATTRIBUTE
194 void __asan_loadN(uptr addr, uptr size) {
195 if (__asan_region_is_poisoned(addr, size)) {
196 GET_CALLER_PC_BP_SP;
197 __asan_report_error(pc, bp, sp, addr, false, size, 0);
198 }
199 }
200
201 extern "C"
202 NOINLINE INTERFACE_ATTRIBUTE
__asan_exp_loadN(uptr addr,uptr size,u32 exp)203 void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
204 if (__asan_region_is_poisoned(addr, size)) {
205 GET_CALLER_PC_BP_SP;
206 __asan_report_error(pc, bp, sp, addr, false, size, exp);
207 }
208 }
209
210 extern "C"
211 NOINLINE INTERFACE_ATTRIBUTE
__asan_storeN(uptr addr,uptr size)212 void __asan_storeN(uptr addr, uptr size) {
213 if (__asan_region_is_poisoned(addr, size)) {
214 GET_CALLER_PC_BP_SP;
215 __asan_report_error(pc, bp, sp, addr, true, size, 0);
216 }
217 }
218
219 extern "C"
220 NOINLINE INTERFACE_ATTRIBUTE
__asan_exp_storeN(uptr addr,uptr size,u32 exp)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 __asan_report_error(pc, bp, sp, addr, true, size, exp);
225 }
226 }
227
228 // Force the linker to keep the symbols for various ASan interface functions.
229 // We want to keep those in the executable in order to let the instrumented
230 // dynamic libraries access the symbol even if it is not used by the executable
231 // itself. This should help if the build system is removing dead code at link
232 // time.
force_interface_symbols()233 static NOINLINE void force_interface_symbols() {
234 volatile int fake_condition = 0; // prevent dead condition elimination.
235 // __asan_report_* functions are noreturn, so we need a switch to prevent
236 // the compiler from removing any of them.
237 switch (fake_condition) {
238 case 1: __asan_report_load1(0); break;
239 case 2: __asan_report_load2(0); break;
240 case 3: __asan_report_load4(0); break;
241 case 4: __asan_report_load8(0); break;
242 case 5: __asan_report_load16(0); break;
243 case 6: __asan_report_load_n(0, 0); break;
244 case 7: __asan_report_store1(0); break;
245 case 8: __asan_report_store2(0); break;
246 case 9: __asan_report_store4(0); break;
247 case 10: __asan_report_store8(0); break;
248 case 11: __asan_report_store16(0); break;
249 case 12: __asan_report_store_n(0, 0); break;
250 case 13: __asan_report_exp_load1(0, 0); break;
251 case 14: __asan_report_exp_load2(0, 0); break;
252 case 15: __asan_report_exp_load4(0, 0); break;
253 case 16: __asan_report_exp_load8(0, 0); break;
254 case 17: __asan_report_exp_load16(0, 0); break;
255 case 18: __asan_report_exp_load_n(0, 0, 0); break;
256 case 19: __asan_report_exp_store1(0, 0); break;
257 case 20: __asan_report_exp_store2(0, 0); break;
258 case 21: __asan_report_exp_store4(0, 0); break;
259 case 22: __asan_report_exp_store8(0, 0); break;
260 case 23: __asan_report_exp_store16(0, 0); break;
261 case 24: __asan_report_exp_store_n(0, 0, 0); break;
262 case 25: __asan_register_globals(0, 0); break;
263 case 26: __asan_unregister_globals(0, 0); break;
264 case 27: __asan_set_death_callback(0); break;
265 case 28: __asan_set_error_report_callback(0); break;
266 case 29: __asan_handle_no_return(); break;
267 case 30: __asan_address_is_poisoned(0); break;
268 case 31: __asan_poison_memory_region(0, 0); break;
269 case 32: __asan_unpoison_memory_region(0, 0); break;
270 case 33: __asan_set_error_exit_code(0); break;
271 case 34: __asan_before_dynamic_init(0); break;
272 case 35: __asan_after_dynamic_init(); break;
273 case 36: __asan_poison_stack_memory(0, 0); break;
274 case 37: __asan_unpoison_stack_memory(0, 0); break;
275 case 38: __asan_region_is_poisoned(0, 0); break;
276 case 39: __asan_describe_address(0); break;
277 }
278 }
279
asan_atexit()280 static void asan_atexit() {
281 Printf("AddressSanitizer exit stats:\n");
282 __asan_print_accumulated_stats();
283 // Print AsanMappingProfile.
284 for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
285 if (AsanMappingProfile[i] == 0) continue;
286 Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
287 }
288 }
289
InitializeHighMemEnd()290 static void InitializeHighMemEnd() {
291 #if !ASAN_FIXED_MAPPING
292 kHighMemEnd = GetMaxVirtualAddress();
293 // Increase kHighMemEnd to make sure it's properly
294 // aligned together with kHighMemBeg:
295 kHighMemEnd |= SHADOW_GRANULARITY * GetPageSizeCached() - 1;
296 #endif // !ASAN_FIXED_MAPPING
297 CHECK_EQ((kHighMemBeg % GetPageSizeCached()), 0);
298 }
299
ProtectGap(uptr addr,uptr size)300 static void ProtectGap(uptr addr, uptr size) {
301 void *res = MmapNoAccess(addr, size);
302 if (addr == (uptr)res)
303 return;
304 Report("ERROR: Failed to protect the shadow gap. "
305 "ASan cannot proceed correctly. ABORTING.\n");
306 DumpProcessMap();
307 Die();
308 }
309
PrintAddressSpaceLayout()310 static void PrintAddressSpaceLayout() {
311 Printf("|| `[%p, %p]` || HighMem ||\n",
312 (void*)kHighMemBeg, (void*)kHighMemEnd);
313 Printf("|| `[%p, %p]` || HighShadow ||\n",
314 (void*)kHighShadowBeg, (void*)kHighShadowEnd);
315 if (kMidMemBeg) {
316 Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
317 (void*)kShadowGap3Beg, (void*)kShadowGap3End);
318 Printf("|| `[%p, %p]` || MidMem ||\n",
319 (void*)kMidMemBeg, (void*)kMidMemEnd);
320 Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
321 (void*)kShadowGap2Beg, (void*)kShadowGap2End);
322 Printf("|| `[%p, %p]` || MidShadow ||\n",
323 (void*)kMidShadowBeg, (void*)kMidShadowEnd);
324 }
325 Printf("|| `[%p, %p]` || ShadowGap ||\n",
326 (void*)kShadowGapBeg, (void*)kShadowGapEnd);
327 if (kLowShadowBeg) {
328 Printf("|| `[%p, %p]` || LowShadow ||\n",
329 (void*)kLowShadowBeg, (void*)kLowShadowEnd);
330 Printf("|| `[%p, %p]` || LowMem ||\n",
331 (void*)kLowMemBeg, (void*)kLowMemEnd);
332 }
333 Printf("MemToShadow(shadow): %p %p %p %p",
334 (void*)MEM_TO_SHADOW(kLowShadowBeg),
335 (void*)MEM_TO_SHADOW(kLowShadowEnd),
336 (void*)MEM_TO_SHADOW(kHighShadowBeg),
337 (void*)MEM_TO_SHADOW(kHighShadowEnd));
338 if (kMidMemBeg) {
339 Printf(" %p %p",
340 (void*)MEM_TO_SHADOW(kMidShadowBeg),
341 (void*)MEM_TO_SHADOW(kMidShadowEnd));
342 }
343 Printf("\n");
344 Printf("redzone=%zu\n", (uptr)flags()->redzone);
345 Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
346 Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
347 Printf("malloc_context_size=%zu\n",
348 (uptr)common_flags()->malloc_context_size);
349
350 Printf("SHADOW_SCALE: %zx\n", (uptr)SHADOW_SCALE);
351 Printf("SHADOW_GRANULARITY: %zx\n", (uptr)SHADOW_GRANULARITY);
352 Printf("SHADOW_OFFSET: %zx\n", (uptr)SHADOW_OFFSET);
353 CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
354 if (kMidMemBeg)
355 CHECK(kMidShadowBeg > kLowShadowEnd &&
356 kMidMemBeg > kMidShadowEnd &&
357 kHighShadowBeg > kMidMemEnd);
358 }
359
AsanInitInternal()360 static void AsanInitInternal() {
361 if (LIKELY(asan_inited)) return;
362 SanitizerToolName = "AddressSanitizer";
363 CHECK(!asan_init_is_running && "ASan init calls itself!");
364 asan_init_is_running = true;
365
366 // Initialize flags. This must be done early, because most of the
367 // initialization steps look at flags().
368 InitializeFlags();
369
370 SetCanPoisonMemory(flags()->poison_heap);
371 SetMallocContextSize(common_flags()->malloc_context_size);
372
373 InitializeHighMemEnd();
374
375 // Make sure we are not statically linked.
376 AsanDoesNotSupportStaticLinkage();
377
378 // Install tool-specific callbacks in sanitizer_common.
379 SetDieCallback(AsanDie);
380 SetCheckFailedCallback(AsanCheckFailed);
381 SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
382
383 __sanitizer_set_report_path(common_flags()->log_path);
384
385 // Enable UAR detection, if required.
386 __asan_option_detect_stack_use_after_return =
387 flags()->detect_stack_use_after_return;
388
389 // Re-exec ourselves if we need to set additional env or command line args.
390 MaybeReexec();
391
392 // Setup internal allocator callback.
393 SetLowLevelAllocateCallback(OnLowLevelAllocate);
394
395 InitializeAsanInterceptors();
396
397 // Enable system log ("adb logcat") on Android.
398 // Doing this before interceptors are initialized crashes in:
399 // AsanInitInternal -> android_log_write -> __interceptor_strcmp
400 AndroidLogInit();
401
402 ReplaceSystemMalloc();
403
404 uptr shadow_start = kLowShadowBeg;
405 if (kLowShadowBeg)
406 shadow_start -= GetMmapGranularity();
407 bool full_shadow_is_available =
408 MemoryRangeIsAvailable(shadow_start, kHighShadowEnd);
409
410 #if SANITIZER_LINUX && defined(__x86_64__) && defined(_LP64) && \
411 !ASAN_FIXED_MAPPING
412 if (!full_shadow_is_available) {
413 kMidMemBeg = kLowMemEnd < 0x3000000000ULL ? 0x3000000000ULL : 0;
414 kMidMemEnd = kLowMemEnd < 0x3000000000ULL ? 0x4fffffffffULL : 0;
415 }
416 #endif
417
418 if (Verbosity()) PrintAddressSpaceLayout();
419
420 DisableCoreDumperIfNecessary();
421
422 if (full_shadow_is_available) {
423 // mmap the low shadow plus at least one page at the left.
424 if (kLowShadowBeg)
425 ReserveShadowMemoryRange(shadow_start, kLowShadowEnd);
426 // mmap the high shadow.
427 ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd);
428 // protect the gap.
429 ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
430 CHECK_EQ(kShadowGapEnd, kHighShadowBeg - 1);
431 } else if (kMidMemBeg &&
432 MemoryRangeIsAvailable(shadow_start, kMidMemBeg - 1) &&
433 MemoryRangeIsAvailable(kMidMemEnd + 1, kHighShadowEnd)) {
434 CHECK(kLowShadowBeg != kLowShadowEnd);
435 // mmap the low shadow plus at least one page at the left.
436 ReserveShadowMemoryRange(shadow_start, kLowShadowEnd);
437 // mmap the mid shadow.
438 ReserveShadowMemoryRange(kMidShadowBeg, kMidShadowEnd);
439 // mmap the high shadow.
440 ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd);
441 // protect the gaps.
442 ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
443 ProtectGap(kShadowGap2Beg, kShadowGap2End - kShadowGap2Beg + 1);
444 ProtectGap(kShadowGap3Beg, kShadowGap3End - kShadowGap3Beg + 1);
445 } else {
446 Report("Shadow memory range interleaves with an existing memory mapping. "
447 "ASan cannot proceed correctly. ABORTING.\n");
448 Report("ASan shadow was supposed to be located in the [%p-%p] range.\n",
449 shadow_start, kHighShadowEnd);
450 DumpProcessMap();
451 Die();
452 }
453
454 AsanTSDInit(PlatformTSDDtor);
455 InstallDeadlySignalHandlers(AsanOnSIGSEGV);
456
457 AllocatorOptions allocator_options;
458 allocator_options.SetFrom(flags(), common_flags());
459 InitializeAllocator(allocator_options);
460
461 MaybeStartBackgroudThread();
462 SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
463
464 // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
465 // should be set to 1 prior to initializing the threads.
466 asan_inited = 1;
467 asan_init_is_running = false;
468
469 if (flags()->atexit)
470 Atexit(asan_atexit);
471
472 InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
473
474 // Now that ASan runtime is (mostly) initialized, deactivate it if
475 // necessary, so that it can be re-activated when requested.
476 if (flags()->start_deactivated)
477 AsanDeactivate();
478
479 // interceptors
480 InitTlsSize();
481
482 // Create main thread.
483 AsanThread *main_thread = AsanThread::Create(
484 /* start_routine */ nullptr, /* arg */ nullptr, /* parent_tid */ 0,
485 /* stack */ nullptr, /* detached */ true);
486 CHECK_EQ(0, main_thread->tid());
487 SetCurrentThread(main_thread);
488 main_thread->ThreadStart(internal_getpid(),
489 /* signal_thread_is_registered */ nullptr);
490 force_interface_symbols(); // no-op.
491 SanitizerInitializeUnwinder();
492
493 #if CAN_SANITIZE_LEAKS
494 __lsan::InitCommonLsan();
495 if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
496 Atexit(__lsan::DoLeakCheck);
497 }
498 #endif // CAN_SANITIZE_LEAKS
499
500 #if CAN_SANITIZE_UB
501 __ubsan::InitAsPlugin();
502 #endif
503
504 InitializeSuppressions();
505
506 VReport(1, "AddressSanitizer Init done\n");
507 }
508
509 // Initialize as requested from some part of ASan runtime library (interceptors,
510 // allocator, etc).
AsanInitFromRtl()511 void AsanInitFromRtl() {
512 AsanInitInternal();
513 }
514
515 #if ASAN_DYNAMIC
516 // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
517 // (and thus normal initializer from .preinit_array haven't run).
518
519 class AsanInitializer {
520 public: // NOLINT
AsanInitializer()521 AsanInitializer() {
522 AsanCheckIncompatibleRT();
523 AsanCheckDynamicRTPrereqs();
524 AsanInitFromRtl();
525 }
526 };
527
528 static AsanInitializer asan_initializer;
529 #endif // ASAN_DYNAMIC
530
531 } // namespace __asan
532
533 // ---------------------- Interface ---------------- {{{1
534 using namespace __asan; // NOLINT
535
__asan_set_error_exit_code(int exit_code)536 int NOINLINE __asan_set_error_exit_code(int exit_code) {
537 int old = flags()->exitcode;
538 flags()->exitcode = exit_code;
539 return old;
540 }
541
__asan_handle_no_return()542 void NOINLINE __asan_handle_no_return() {
543 int local_stack;
544 AsanThread *curr_thread = GetCurrentThread();
545 CHECK(curr_thread);
546 uptr PageSize = GetPageSizeCached();
547 uptr top = curr_thread->stack_top();
548 uptr bottom = ((uptr)&local_stack - PageSize) & ~(PageSize-1);
549 static const uptr kMaxExpectedCleanupSize = 64 << 20; // 64M
550 if (top - bottom > kMaxExpectedCleanupSize) {
551 static bool reported_warning = false;
552 if (reported_warning)
553 return;
554 reported_warning = true;
555 Report("WARNING: ASan is ignoring requested __asan_handle_no_return: "
556 "stack top: %p; bottom %p; size: %p (%zd)\n"
557 "False positive error reports may follow\n"
558 "For details see "
559 "http://code.google.com/p/address-sanitizer/issues/detail?id=189\n",
560 top, bottom, top - bottom, top - bottom);
561 return;
562 }
563 PoisonShadow(bottom, top - bottom, 0);
564 if (curr_thread->has_fake_stack())
565 curr_thread->fake_stack()->HandleNoReturn();
566 }
567
__asan_set_death_callback(void (* callback)(void))568 void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
569 SetUserDieCallback(callback);
570 }
571
572 // Initialize as requested from instrumented application code.
573 // We use this call as a trigger to wake up ASan from deactivated state.
__asan_init()574 void __asan_init() {
575 AsanCheckIncompatibleRT();
576 AsanActivate();
577 AsanInitInternal();
578 }
579