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
34int __asan_option_detect_stack_use_after_return;  // Global interface symbol.
35uptr *__asan_test_only_reported_buggy_pointer;  // Used only for testing asan.
36
37namespace __asan {
38
39uptr AsanMappingProfile[kAsanMappingProfileSize];
40
41static 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
66static 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
76int asan_inited;
77bool asan_init_is_running;
78
79#if !ASAN_FIXED_MAPPING
80uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
81#endif
82
83// -------------------------- Misc ---------------- {{{1
84void 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.
92void 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
110static 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)                     \
117extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
118void __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}                                                                   \
122extern "C" NOINLINE INTERFACE_ATTRIBUTE                             \
123void __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
128ASAN_REPORT_ERROR(load, false, 1)
129ASAN_REPORT_ERROR(load, false, 2)
130ASAN_REPORT_ERROR(load, false, 4)
131ASAN_REPORT_ERROR(load, false, 8)
132ASAN_REPORT_ERROR(load, false, 16)
133ASAN_REPORT_ERROR(store, true, 1)
134ASAN_REPORT_ERROR(store, true, 2)
135ASAN_REPORT_ERROR(store, true, 4)
136ASAN_REPORT_ERROR(store, true, 8)
137ASAN_REPORT_ERROR(store, true, 16)
138
139#define ASAN_REPORT_ERROR_N(type, is_write)                    \
140extern "C" NOINLINE INTERFACE_ATTRIBUTE                        \
141void __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}                                                              \
145extern "C" NOINLINE INTERFACE_ATTRIBUTE                        \
146void __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
151ASAN_REPORT_ERROR_N(load, false)
152ASAN_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
181ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
182ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
183ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
184ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
185ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
186ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
187ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
188ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
189ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
190ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
191
192extern "C"
193NOINLINE INTERFACE_ATTRIBUTE
194void __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
201extern "C"
202NOINLINE INTERFACE_ATTRIBUTE
203void __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
210extern "C"
211NOINLINE INTERFACE_ATTRIBUTE
212void __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
219extern "C"
220NOINLINE INTERFACE_ATTRIBUTE
221void __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.
233static 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
280static 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
290static 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
300static 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
310static 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
360static 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).
511void 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
519class AsanInitializer {
520public:  // NOLINT
521  AsanInitializer() {
522    AsanCheckIncompatibleRT();
523    AsanCheckDynamicRTPrereqs();
524    AsanInitFromRtl();
525  }
526};
527
528static AsanInitializer asan_initializer;
529#endif  // ASAN_DYNAMIC
530
531}  // namespace __asan
532
533// ---------------------- Interface ---------------- {{{1
534using namespace __asan;  // NOLINT
535
536int NOINLINE __asan_set_error_exit_code(int exit_code) {
537  int old = flags()->exitcode;
538  flags()->exitcode = exit_code;
539  return old;
540}
541
542void 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
568void 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.
574void __asan_init() {
575  AsanCheckIncompatibleRT();
576  AsanActivate();
577  AsanInitInternal();
578}
579