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
15 #include "asan_activation.h"
16 #include "asan_allocator.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 "sanitizer_common/sanitizer_atomic.h"
28 #include "sanitizer_common/sanitizer_flags.h"
29 #include "sanitizer_common/sanitizer_libc.h"
30 #include "sanitizer_common/sanitizer_symbolizer.h"
31 #include "lsan/lsan_common.h"
32 #include "ubsan/ubsan_init.h"
33 #include "ubsan/ubsan_platform.h"
34
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 (flags()->sleep_before_dying) {
49 Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
50 SleepForSeconds(flags()->sleep_before_dying);
51 }
52 if (flags()->unmap_shadow_on_exit) {
53 if (kMidMemBeg) {
54 UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
55 UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
56 } else {
57 UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
58 }
59 }
60 }
61
AsanCheckFailed(const char * file,int line,const char * cond,u64 v1,u64 v2)62 static void AsanCheckFailed(const char *file, int line, const char *cond,
63 u64 v1, u64 v2) {
64 Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
65 line, cond, (uptr)v1, (uptr)v2);
66 // FIXME: check for infinite recursion without a thread-local counter here.
67 PRINT_CURRENT_STACK_CHECK();
68 Die();
69 }
70
71 // -------------------------- Globals --------------------- {{{1
72 int asan_inited;
73 bool asan_init_is_running;
74
75 #if !ASAN_FIXED_MAPPING
76 uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
77 #endif
78
79 // -------------------------- Misc ---------------- {{{1
ShowStatsAndAbort()80 void ShowStatsAndAbort() {
81 __asan_print_accumulated_stats();
82 Die();
83 }
84
85 // ---------------------- mmap -------------------- {{{1
86 // Reserve memory range [beg, end].
87 // We need to use inclusive range because end+1 may not be representable.
ReserveShadowMemoryRange(uptr beg,uptr end,const char * name)88 void ReserveShadowMemoryRange(uptr beg, uptr end, const char *name) {
89 CHECK_EQ((beg % GetMmapGranularity()), 0);
90 CHECK_EQ(((end + 1) % GetMmapGranularity()), 0);
91 uptr size = end - beg + 1;
92 DecreaseTotalMmap(size); // Don't count the shadow against mmap_limit_mb.
93 void *res = MmapFixedNoReserve(beg, size, name);
94 if (res != (void*)beg) {
95 Report("ReserveShadowMemoryRange failed while trying to map 0x%zx bytes. "
96 "Perhaps you're using ulimit -v\n", size);
97 Abort();
98 }
99 if (common_flags()->no_huge_pages_for_shadow)
100 NoHugePagesInRegion(beg, size);
101 if (common_flags()->use_madv_dontdump)
102 DontDumpShadowMemory(beg, size);
103 }
104
105 // --------------- LowLevelAllocateCallbac ---------- {{{1
OnLowLevelAllocate(uptr ptr,uptr size)106 static void OnLowLevelAllocate(uptr ptr, uptr size) {
107 PoisonShadow(ptr, size, kAsanInternalHeapMagic);
108 }
109
110 // -------------------------- Run-time entry ------------------- {{{1
111 // exported functions
112 #define ASAN_REPORT_ERROR(type, is_write, size) \
113 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
114 void __asan_report_ ## type ## size(uptr addr) { \
115 GET_CALLER_PC_BP_SP; \
116 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true); \
117 } \
118 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
119 void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) { \
120 GET_CALLER_PC_BP_SP; \
121 ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true); \
122 } \
123 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
124 void __asan_report_ ## type ## size ## _noabort(uptr addr) { \
125 GET_CALLER_PC_BP_SP; \
126 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false); \
127 } \
128
129 ASAN_REPORT_ERROR(load, false, 1)
130 ASAN_REPORT_ERROR(load, false, 2)
131 ASAN_REPORT_ERROR(load, false, 4)
132 ASAN_REPORT_ERROR(load, false, 8)
133 ASAN_REPORT_ERROR(load, false, 16)
134 ASAN_REPORT_ERROR(store, true, 1)
135 ASAN_REPORT_ERROR(store, true, 2)
136 ASAN_REPORT_ERROR(store, true, 4)
137 ASAN_REPORT_ERROR(store, true, 8)
138 ASAN_REPORT_ERROR(store, true, 16)
139
140 #define ASAN_REPORT_ERROR_N(type, is_write) \
141 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
142 void __asan_report_ ## type ## _n(uptr addr, uptr size) { \
143 GET_CALLER_PC_BP_SP; \
144 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true); \
145 } \
146 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
147 void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) { \
148 GET_CALLER_PC_BP_SP; \
149 ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true); \
150 } \
151 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
152 void __asan_report_ ## type ## _n_noabort(uptr addr, uptr size) { \
153 GET_CALLER_PC_BP_SP; \
154 ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false); \
155 } \
156
ASAN_REPORT_ERROR_N(load,false)157 ASAN_REPORT_ERROR_N(load, false)
158 ASAN_REPORT_ERROR_N(store, true)
159
160 #define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg, fatal) \
161 uptr sp = MEM_TO_SHADOW(addr); \
162 uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp) \
163 : *reinterpret_cast<u16 *>(sp); \
164 if (UNLIKELY(s)) { \
165 if (UNLIKELY(size >= SHADOW_GRANULARITY || \
166 ((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >= \
167 (s8)s)) { \
168 if (__asan_test_only_reported_buggy_pointer) { \
169 *__asan_test_only_reported_buggy_pointer = addr; \
170 } else { \
171 GET_CALLER_PC_BP_SP; \
172 ReportGenericError(pc, bp, sp, addr, is_write, size, exp_arg, \
173 fatal); \
174 } \
175 } \
176 }
177
178 #define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size) \
179 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
180 void __asan_##type##size(uptr addr) { \
181 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, true) \
182 } \
183 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
184 void __asan_exp_##type##size(uptr addr, u32 exp) { \
185 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp, true) \
186 } \
187 extern "C" NOINLINE INTERFACE_ATTRIBUTE \
188 void __asan_##type##size ## _noabort(uptr addr) { \
189 ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, false) \
190 } \
191
192 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
193 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
194 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
195 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
196 ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
197 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
198 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
199 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
200 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
201 ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
202
203 extern "C"
204 NOINLINE INTERFACE_ATTRIBUTE
205 void __asan_loadN(uptr addr, uptr size) {
206 if (__asan_region_is_poisoned(addr, size)) {
207 GET_CALLER_PC_BP_SP;
208 ReportGenericError(pc, bp, sp, addr, false, size, 0, true);
209 }
210 }
211
212 extern "C"
213 NOINLINE INTERFACE_ATTRIBUTE
__asan_exp_loadN(uptr addr,uptr size,u32 exp)214 void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
215 if (__asan_region_is_poisoned(addr, size)) {
216 GET_CALLER_PC_BP_SP;
217 ReportGenericError(pc, bp, sp, addr, false, size, exp, true);
218 }
219 }
220
221 extern "C"
222 NOINLINE INTERFACE_ATTRIBUTE
__asan_loadN_noabort(uptr addr,uptr size)223 void __asan_loadN_noabort(uptr addr, uptr size) {
224 if (__asan_region_is_poisoned(addr, size)) {
225 GET_CALLER_PC_BP_SP;
226 ReportGenericError(pc, bp, sp, addr, false, size, 0, false);
227 }
228 }
229
230 extern "C"
231 NOINLINE INTERFACE_ATTRIBUTE
__asan_storeN(uptr addr,uptr size)232 void __asan_storeN(uptr addr, uptr size) {
233 if (__asan_region_is_poisoned(addr, size)) {
234 GET_CALLER_PC_BP_SP;
235 ReportGenericError(pc, bp, sp, addr, true, size, 0, true);
236 }
237 }
238
239 extern "C"
240 NOINLINE INTERFACE_ATTRIBUTE
__asan_exp_storeN(uptr addr,uptr size,u32 exp)241 void __asan_exp_storeN(uptr addr, uptr size, u32 exp) {
242 if (__asan_region_is_poisoned(addr, size)) {
243 GET_CALLER_PC_BP_SP;
244 ReportGenericError(pc, bp, sp, addr, true, size, exp, true);
245 }
246 }
247
248 extern "C"
249 NOINLINE INTERFACE_ATTRIBUTE
__asan_storeN_noabort(uptr addr,uptr size)250 void __asan_storeN_noabort(uptr addr, uptr size) {
251 if (__asan_region_is_poisoned(addr, size)) {
252 GET_CALLER_PC_BP_SP;
253 ReportGenericError(pc, bp, sp, addr, true, size, 0, false);
254 }
255 }
256
257 // Force the linker to keep the symbols for various ASan interface functions.
258 // We want to keep those in the executable in order to let the instrumented
259 // dynamic libraries access the symbol even if it is not used by the executable
260 // itself. This should help if the build system is removing dead code at link
261 // time.
force_interface_symbols()262 static NOINLINE void force_interface_symbols() {
263 volatile int fake_condition = 0; // prevent dead condition elimination.
264 // __asan_report_* functions are noreturn, so we need a switch to prevent
265 // the compiler from removing any of them.
266 switch (fake_condition) {
267 case 1: __asan_report_load1(0); break;
268 case 2: __asan_report_load2(0); break;
269 case 3: __asan_report_load4(0); break;
270 case 4: __asan_report_load8(0); break;
271 case 5: __asan_report_load16(0); break;
272 case 6: __asan_report_load_n(0, 0); break;
273 case 7: __asan_report_store1(0); break;
274 case 8: __asan_report_store2(0); break;
275 case 9: __asan_report_store4(0); break;
276 case 10: __asan_report_store8(0); break;
277 case 11: __asan_report_store16(0); break;
278 case 12: __asan_report_store_n(0, 0); break;
279 case 13: __asan_report_exp_load1(0, 0); break;
280 case 14: __asan_report_exp_load2(0, 0); break;
281 case 15: __asan_report_exp_load4(0, 0); break;
282 case 16: __asan_report_exp_load8(0, 0); break;
283 case 17: __asan_report_exp_load16(0, 0); break;
284 case 18: __asan_report_exp_load_n(0, 0, 0); break;
285 case 19: __asan_report_exp_store1(0, 0); break;
286 case 20: __asan_report_exp_store2(0, 0); break;
287 case 21: __asan_report_exp_store4(0, 0); break;
288 case 22: __asan_report_exp_store8(0, 0); break;
289 case 23: __asan_report_exp_store16(0, 0); break;
290 case 24: __asan_report_exp_store_n(0, 0, 0); break;
291 case 25: __asan_register_globals(nullptr, 0); break;
292 case 26: __asan_unregister_globals(nullptr, 0); break;
293 case 27: __asan_set_death_callback(nullptr); break;
294 case 28: __asan_set_error_report_callback(nullptr); break;
295 case 29: __asan_handle_no_return(); break;
296 case 30: __asan_address_is_poisoned(nullptr); break;
297 case 31: __asan_poison_memory_region(nullptr, 0); break;
298 case 32: __asan_unpoison_memory_region(nullptr, 0); break;
299 case 34: __asan_before_dynamic_init(nullptr); break;
300 case 35: __asan_after_dynamic_init(); break;
301 case 36: __asan_poison_stack_memory(0, 0); break;
302 case 37: __asan_unpoison_stack_memory(0, 0); break;
303 case 38: __asan_region_is_poisoned(0, 0); break;
304 case 39: __asan_describe_address(0); break;
305 }
306 }
307
asan_atexit()308 static void asan_atexit() {
309 Printf("AddressSanitizer exit stats:\n");
310 __asan_print_accumulated_stats();
311 // Print AsanMappingProfile.
312 for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
313 if (AsanMappingProfile[i] == 0) continue;
314 Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
315 }
316 }
317
InitializeHighMemEnd()318 static void InitializeHighMemEnd() {
319 #if !ASAN_FIXED_MAPPING
320 kHighMemEnd = GetMaxVirtualAddress();
321 // Increase kHighMemEnd to make sure it's properly
322 // aligned together with kHighMemBeg:
323 kHighMemEnd |= SHADOW_GRANULARITY * GetMmapGranularity() - 1;
324 #endif // !ASAN_FIXED_MAPPING
325 CHECK_EQ((kHighMemBeg % GetMmapGranularity()), 0);
326 }
327
ProtectGap(uptr addr,uptr size)328 static void ProtectGap(uptr addr, uptr size) {
329 if (!flags()->protect_shadow_gap)
330 return;
331 void *res = MmapFixedNoAccess(addr, size, "shadow gap");
332 if (addr == (uptr)res)
333 return;
334 // A few pages at the start of the address space can not be protected.
335 // But we really want to protect as much as possible, to prevent this memory
336 // being returned as a result of a non-FIXED mmap().
337 if (addr == kZeroBaseShadowStart) {
338 uptr step = GetMmapGranularity();
339 while (size > step && addr < kZeroBaseMaxShadowStart) {
340 addr += step;
341 size -= step;
342 void *res = MmapFixedNoAccess(addr, size, "shadow gap");
343 if (addr == (uptr)res)
344 return;
345 }
346 }
347
348 Report("ERROR: Failed to protect the shadow gap. "
349 "ASan cannot proceed correctly. ABORTING.\n");
350 DumpProcessMap();
351 Die();
352 }
353
PrintAddressSpaceLayout()354 static void PrintAddressSpaceLayout() {
355 Printf("|| `[%p, %p]` || HighMem ||\n",
356 (void*)kHighMemBeg, (void*)kHighMemEnd);
357 Printf("|| `[%p, %p]` || HighShadow ||\n",
358 (void*)kHighShadowBeg, (void*)kHighShadowEnd);
359 if (kMidMemBeg) {
360 Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
361 (void*)kShadowGap3Beg, (void*)kShadowGap3End);
362 Printf("|| `[%p, %p]` || MidMem ||\n",
363 (void*)kMidMemBeg, (void*)kMidMemEnd);
364 Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
365 (void*)kShadowGap2Beg, (void*)kShadowGap2End);
366 Printf("|| `[%p, %p]` || MidShadow ||\n",
367 (void*)kMidShadowBeg, (void*)kMidShadowEnd);
368 }
369 Printf("|| `[%p, %p]` || ShadowGap ||\n",
370 (void*)kShadowGapBeg, (void*)kShadowGapEnd);
371 if (kLowShadowBeg) {
372 Printf("|| `[%p, %p]` || LowShadow ||\n",
373 (void*)kLowShadowBeg, (void*)kLowShadowEnd);
374 Printf("|| `[%p, %p]` || LowMem ||\n",
375 (void*)kLowMemBeg, (void*)kLowMemEnd);
376 }
377 Printf("MemToShadow(shadow): %p %p %p %p",
378 (void*)MEM_TO_SHADOW(kLowShadowBeg),
379 (void*)MEM_TO_SHADOW(kLowShadowEnd),
380 (void*)MEM_TO_SHADOW(kHighShadowBeg),
381 (void*)MEM_TO_SHADOW(kHighShadowEnd));
382 if (kMidMemBeg) {
383 Printf(" %p %p",
384 (void*)MEM_TO_SHADOW(kMidShadowBeg),
385 (void*)MEM_TO_SHADOW(kMidShadowEnd));
386 }
387 Printf("\n");
388 Printf("redzone=%zu\n", (uptr)flags()->redzone);
389 Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
390 Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
391 Printf("malloc_context_size=%zu\n",
392 (uptr)common_flags()->malloc_context_size);
393
394 Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE);
395 Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY);
396 Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET);
397 CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
398 if (kMidMemBeg)
399 CHECK(kMidShadowBeg > kLowShadowEnd &&
400 kMidMemBeg > kMidShadowEnd &&
401 kHighShadowBeg > kMidMemEnd);
402 }
403
AsanInitInternal()404 static void AsanInitInternal() {
405 if (LIKELY(asan_inited)) return;
406 SanitizerToolName = "AddressSanitizer";
407 CHECK(!asan_init_is_running && "ASan init calls itself!");
408 asan_init_is_running = true;
409
410 CacheBinaryName();
411
412 // Initialize flags. This must be done early, because most of the
413 // initialization steps look at flags().
414 InitializeFlags();
415
416 AsanCheckIncompatibleRT();
417 AsanCheckDynamicRTPrereqs();
418 AvoidCVE_2016_2143();
419
420 SetCanPoisonMemory(flags()->poison_heap);
421 SetMallocContextSize(common_flags()->malloc_context_size);
422
423 InitializePlatformExceptionHandlers();
424
425 InitializeHighMemEnd();
426
427 // Make sure we are not statically linked.
428 AsanDoesNotSupportStaticLinkage();
429
430 // Install tool-specific callbacks in sanitizer_common.
431 AddDieCallback(AsanDie);
432 SetCheckFailedCallback(AsanCheckFailed);
433 SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
434
435 __sanitizer_set_report_path(common_flags()->log_path);
436
437 // Enable UAR detection, if required.
438 __asan_option_detect_stack_use_after_return =
439 flags()->detect_stack_use_after_return;
440
441 // Re-exec ourselves if we need to set additional env or command line args.
442 MaybeReexec();
443
444 // Setup internal allocator callback.
445 SetLowLevelAllocateCallback(OnLowLevelAllocate);
446
447 InitializeAsanInterceptors();
448
449 // Enable system log ("adb logcat") on Android.
450 // Doing this before interceptors are initialized crashes in:
451 // AsanInitInternal -> android_log_write -> __interceptor_strcmp
452 AndroidLogInit();
453
454 ReplaceSystemMalloc();
455
456 uptr shadow_start = kLowShadowBeg;
457 if (kLowShadowBeg)
458 shadow_start -= GetMmapGranularity();
459 bool full_shadow_is_available =
460 MemoryRangeIsAvailable(shadow_start, kHighShadowEnd);
461
462 #if SANITIZER_LINUX && defined(__x86_64__) && defined(_LP64) && \
463 !ASAN_FIXED_MAPPING
464 if (!full_shadow_is_available) {
465 kMidMemBeg = kLowMemEnd < 0x3000000000ULL ? 0x3000000000ULL : 0;
466 kMidMemEnd = kLowMemEnd < 0x3000000000ULL ? 0x4fffffffffULL : 0;
467 }
468 #elif SANITIZER_WINDOWS64
469 // Disable the "mid mem" shadow layout.
470 if (!full_shadow_is_available) {
471 kMidMemBeg = 0;
472 kMidMemEnd = 0;
473 }
474 #endif
475
476 if (Verbosity()) PrintAddressSpaceLayout();
477
478 DisableCoreDumperIfNecessary();
479
480 if (full_shadow_is_available) {
481 // mmap the low shadow plus at least one page at the left.
482 if (kLowShadowBeg)
483 ReserveShadowMemoryRange(shadow_start, kLowShadowEnd, "low shadow");
484 // mmap the high shadow.
485 ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd, "high shadow");
486 // protect the gap.
487 ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
488 CHECK_EQ(kShadowGapEnd, kHighShadowBeg - 1);
489 } else if (kMidMemBeg &&
490 MemoryRangeIsAvailable(shadow_start, kMidMemBeg - 1) &&
491 MemoryRangeIsAvailable(kMidMemEnd + 1, kHighShadowEnd)) {
492 CHECK(kLowShadowBeg != kLowShadowEnd);
493 // mmap the low shadow plus at least one page at the left.
494 ReserveShadowMemoryRange(shadow_start, kLowShadowEnd, "low shadow");
495 // mmap the mid shadow.
496 ReserveShadowMemoryRange(kMidShadowBeg, kMidShadowEnd, "mid shadow");
497 // mmap the high shadow.
498 ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd, "high shadow");
499 // protect the gaps.
500 ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
501 ProtectGap(kShadowGap2Beg, kShadowGap2End - kShadowGap2Beg + 1);
502 ProtectGap(kShadowGap3Beg, kShadowGap3End - kShadowGap3Beg + 1);
503 } else {
504 Report("Shadow memory range interleaves with an existing memory mapping. "
505 "ASan cannot proceed correctly. ABORTING.\n");
506 Report("ASan shadow was supposed to be located in the [%p-%p] range.\n",
507 shadow_start, kHighShadowEnd);
508 DumpProcessMap();
509 Die();
510 }
511
512 AsanTSDInit(PlatformTSDDtor);
513 InstallDeadlySignalHandlers(AsanOnDeadlySignal);
514
515 AllocatorOptions allocator_options;
516 allocator_options.SetFrom(flags(), common_flags());
517 InitializeAllocator(allocator_options);
518
519 MaybeStartBackgroudThread();
520 SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
521
522 // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
523 // should be set to 1 prior to initializing the threads.
524 asan_inited = 1;
525 asan_init_is_running = false;
526
527 if (flags()->atexit)
528 Atexit(asan_atexit);
529
530 InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
531
532 // Now that ASan runtime is (mostly) initialized, deactivate it if
533 // necessary, so that it can be re-activated when requested.
534 if (flags()->start_deactivated)
535 AsanDeactivate();
536
537 // interceptors
538 InitTlsSize();
539
540 // Create main thread.
541 AsanThread *main_thread = AsanThread::Create(
542 /* start_routine */ nullptr, /* arg */ nullptr, /* parent_tid */ 0,
543 /* stack */ nullptr, /* detached */ true);
544 CHECK_EQ(0, main_thread->tid());
545 SetCurrentThread(main_thread);
546 main_thread->ThreadStart(internal_getpid(),
547 /* signal_thread_is_registered */ nullptr);
548 force_interface_symbols(); // no-op.
549 SanitizerInitializeUnwinder();
550
551 if (CAN_SANITIZE_LEAKS) {
552 __lsan::InitCommonLsan();
553 if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
554 Atexit(__lsan::DoLeakCheck);
555 }
556 }
557
558 #if CAN_SANITIZE_UB
559 __ubsan::InitAsPlugin();
560 #endif
561
562 InitializeSuppressions();
563
564 if (CAN_SANITIZE_LEAKS) {
565 // LateInitialize() calls dlsym, which can allocate an error string buffer
566 // in the TLS. Let's ignore the allocation to avoid reporting a leak.
567 __lsan::ScopedInterceptorDisabler disabler;
568 Symbolizer::LateInitialize();
569 } else {
570 Symbolizer::LateInitialize();
571 }
572
573 VReport(1, "AddressSanitizer Init done\n");
574 }
575
576 // Initialize as requested from some part of ASan runtime library (interceptors,
577 // allocator, etc).
AsanInitFromRtl()578 void AsanInitFromRtl() {
579 AsanInitInternal();
580 }
581
582 #if ASAN_DYNAMIC
583 // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
584 // (and thus normal initializers from .preinit_array or modules haven't run).
585
586 class AsanInitializer {
587 public: // NOLINT
AsanInitializer()588 AsanInitializer() {
589 AsanInitFromRtl();
590 }
591 };
592
593 static AsanInitializer asan_initializer;
594 #endif // ASAN_DYNAMIC
595
596 } // namespace __asan
597
598 // ---------------------- Interface ---------------- {{{1
599 using namespace __asan; // NOLINT
600
__asan_handle_no_return()601 void NOINLINE __asan_handle_no_return() {
602 int local_stack;
603 AsanThread *curr_thread = GetCurrentThread();
604 uptr PageSize = GetPageSizeCached();
605 uptr top, bottom;
606 if (curr_thread) {
607 top = curr_thread->stack_top();
608 bottom = ((uptr)&local_stack - PageSize) & ~(PageSize - 1);
609 } else {
610 // If we haven't seen this thread, try asking the OS for stack bounds.
611 uptr tls_addr, tls_size, stack_size;
612 GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr,
613 &tls_size);
614 top = bottom + stack_size;
615 }
616 static const uptr kMaxExpectedCleanupSize = 64 << 20; // 64M
617 if (top - bottom > kMaxExpectedCleanupSize) {
618 static bool reported_warning = false;
619 if (reported_warning)
620 return;
621 reported_warning = true;
622 Report("WARNING: ASan is ignoring requested __asan_handle_no_return: "
623 "stack top: %p; bottom %p; size: %p (%zd)\n"
624 "False positive error reports may follow\n"
625 "For details see "
626 "https://github.com/google/sanitizers/issues/189\n",
627 top, bottom, top - bottom, top - bottom);
628 return;
629 }
630 PoisonShadow(bottom, top - bottom, 0);
631 if (curr_thread && curr_thread->has_fake_stack())
632 curr_thread->fake_stack()->HandleNoReturn();
633 }
634
__asan_set_death_callback(void (* callback)(void))635 void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
636 SetUserDieCallback(callback);
637 }
638
639 // Initialize as requested from instrumented application code.
640 // We use this call as a trigger to wake up ASan from deactivated state.
__asan_init()641 void __asan_init() {
642 AsanActivate();
643 AsanInitInternal();
644 }
645
__asan_version_mismatch_check()646 void __asan_version_mismatch_check() {
647 // Do nothing.
648 }
649