asan_rtl.cc revision dfeef67b23ba92bbee598293164ee20078f633a1 
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_allocator.h"
15#include "asan_interceptors.h"
16#include "asan_internal.h"
17#include "asan_mapping.h"
18#include "asan_poisoning.h"
19#include "asan_report.h"
20#include "asan_stack.h"
21#include "asan_stats.h"
22#include "asan_thread.h"
23#include "sanitizer_common/sanitizer_atomic.h"
24#include "sanitizer_common/sanitizer_flags.h"
25#include "sanitizer_common/sanitizer_libc.h"
26#include "sanitizer_common/sanitizer_symbolizer.h"
27
28namespace __asan {
29
30uptr AsanMappingProfile[kAsanMappingProfileSize];
31
32static void AsanDie() {
33  static atomic_uint32_t num_calls;
34  if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
35    // Don't die twice - run a busy loop.
36    while (1) { }
37  }
38  if (flags()->sleep_before_dying) {
39    Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
40    SleepForSeconds(flags()->sleep_before_dying);
41  }
42  if (flags()->unmap_shadow_on_exit) {
43    if (kMidMemBeg) {
44      UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
45      UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
46    } else {
47      UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
48    }
49  }
50  if (death_callback)
51    death_callback();
52  if (flags()->abort_on_error)
53    Abort();
54  internal__exit(flags()->exitcode);
55}
56
57static void AsanCheckFailed(const char *file, int line, const char *cond,
58                            u64 v1, u64 v2) {
59  Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n",
60             file, line, cond, (uptr)v1, (uptr)v2);
61  // FIXME: check for infinite recursion without a thread-local counter here.
62  PRINT_CURRENT_STACK();
63  Die();
64}
65
66// -------------------------- Flags ------------------------- {{{1
67static const int kDefaultMallocContextSize = 30;
68
69Flags asan_flags_dont_use_directly;  // use via flags().
70
71static const char *MaybeCallAsanDefaultOptions() {
72  return (&__asan_default_options) ? __asan_default_options() : "";
73}
74
75static const char *MaybeUseAsanDefaultOptionsCompileDefiniton() {
76#ifdef ASAN_DEFAULT_OPTIONS
77// Stringize the macro value.
78# define ASAN_STRINGIZE(x) #x
79# define ASAN_STRINGIZE_OPTIONS(options) ASAN_STRINGIZE(options)
80  return ASAN_STRINGIZE_OPTIONS(ASAN_DEFAULT_OPTIONS);
81#else
82  return "";
83#endif
84}
85
86static void ParseFlagsFromString(Flags *f, const char *str) {
87  ParseFlag(str, &f->quarantine_size, "quarantine_size");
88  ParseFlag(str, &f->symbolize, "symbolize");
89  ParseFlag(str, &f->verbosity, "verbosity");
90  ParseFlag(str, &f->redzone, "redzone");
91  CHECK_GE(f->redzone, 16);
92  CHECK(IsPowerOfTwo(f->redzone));
93
94  ParseFlag(str, &f->debug, "debug");
95  ParseFlag(str, &f->report_globals, "report_globals");
96  ParseFlag(str, &f->check_initialization_order, "check_initialization_order");
97  ParseFlag(str, &f->malloc_context_size, "malloc_context_size");
98  CHECK((uptr)f->malloc_context_size <= kStackTraceMax);
99
100  ParseFlag(str, &f->replace_str, "replace_str");
101  ParseFlag(str, &f->replace_intrin, "replace_intrin");
102  ParseFlag(str, &f->mac_ignore_invalid_free, "mac_ignore_invalid_free");
103  ParseFlag(str, &f->use_fake_stack, "use_fake_stack");
104  ParseFlag(str, &f->max_malloc_fill_size, "max_malloc_fill_size");
105  ParseFlag(str, &f->malloc_fill_byte, "malloc_fill_byte");
106  ParseFlag(str, &f->exitcode, "exitcode");
107  ParseFlag(str, &f->allow_user_poisoning, "allow_user_poisoning");
108  ParseFlag(str, &f->sleep_before_dying, "sleep_before_dying");
109  ParseFlag(str, &f->handle_segv, "handle_segv");
110  ParseFlag(str, &f->use_sigaltstack, "use_sigaltstack");
111  ParseFlag(str, &f->check_malloc_usable_size, "check_malloc_usable_size");
112  ParseFlag(str, &f->unmap_shadow_on_exit, "unmap_shadow_on_exit");
113  ParseFlag(str, &f->abort_on_error, "abort_on_error");
114  ParseFlag(str, &f->print_stats, "print_stats");
115  ParseFlag(str, &f->print_legend, "print_legend");
116  ParseFlag(str, &f->atexit, "atexit");
117  ParseFlag(str, &f->disable_core, "disable_core");
118  ParseFlag(str, &f->strip_path_prefix, "strip_path_prefix");
119  ParseFlag(str, &f->allow_reexec, "allow_reexec");
120  ParseFlag(str, &f->print_full_thread_history, "print_full_thread_history");
121  ParseFlag(str, &f->log_path, "log_path");
122  ParseFlag(str, &f->fast_unwind_on_fatal, "fast_unwind_on_fatal");
123  ParseFlag(str, &f->fast_unwind_on_malloc, "fast_unwind_on_malloc");
124  ParseFlag(str, &f->poison_heap, "poison_heap");
125  ParseFlag(str, &f->alloc_dealloc_mismatch, "alloc_dealloc_mismatch");
126  ParseFlag(str, &f->use_stack_depot, "use_stack_depot");
127  ParseFlag(str, &f->strict_memcmp, "strict_memcmp");
128  ParseFlag(str, &f->strict_init_order, "strict_init_order");
129}
130
131static const char *asan_external_symbolizer;
132
133void InitializeFlags(Flags *f, const char *env) {
134  internal_memset(f, 0, sizeof(*f));
135
136  f->quarantine_size = (ASAN_LOW_MEMORY) ? 1UL << 26 : 1UL << 28;
137  f->symbolize = (asan_external_symbolizer != 0);
138  f->verbosity = 0;
139  f->redzone = 16;
140  f->debug = false;
141  f->report_globals = 1;
142  f->check_initialization_order = false;
143  f->malloc_context_size = kDefaultMallocContextSize;
144  f->replace_str = true;
145  f->replace_intrin = true;
146  f->mac_ignore_invalid_free = false;
147  f->use_fake_stack = true;
148  f->max_malloc_fill_size = 0x1000;  // By default, fill only the first 4K.
149  f->malloc_fill_byte = 0xbe;
150  f->exitcode = ASAN_DEFAULT_FAILURE_EXITCODE;
151  f->allow_user_poisoning = true;
152  f->sleep_before_dying = 0;
153  f->handle_segv = ASAN_NEEDS_SEGV;
154  f->use_sigaltstack = false;
155  f->check_malloc_usable_size = true;
156  f->unmap_shadow_on_exit = false;
157  f->abort_on_error = false;
158  f->print_stats = false;
159  f->print_legend = true;
160  f->atexit = false;
161  f->disable_core = (SANITIZER_WORDSIZE == 64);
162  f->strip_path_prefix = "";
163  f->allow_reexec = true;
164  f->print_full_thread_history = true;
165  f->log_path = 0;
166  f->fast_unwind_on_fatal = false;
167  f->fast_unwind_on_malloc = true;
168  f->poison_heap = true;
169  // Turn off alloc/dealloc mismatch checker on Mac for now.
170  // TODO(glider): Fix known issues and enable this back.
171  f->alloc_dealloc_mismatch = (SANITIZER_MAC == 0);;
172  f->use_stack_depot = true;  // Only affects allocator2.
173  f->strict_memcmp = true;
174  f->strict_init_order = false;
175
176  // Override from compile definition.
177  ParseFlagsFromString(f, MaybeUseAsanDefaultOptionsCompileDefiniton());
178
179  // Override from user-specified string.
180  ParseFlagsFromString(f, MaybeCallAsanDefaultOptions());
181  if (flags()->verbosity) {
182    Report("Using the defaults from __asan_default_options: %s\n",
183           MaybeCallAsanDefaultOptions());
184  }
185
186  // Override from command line.
187  ParseFlagsFromString(f, env);
188}
189
190// -------------------------- Globals --------------------- {{{1
191int asan_inited;
192bool asan_init_is_running;
193void (*death_callback)(void);
194
195#if !ASAN_FIXED_MAPPING
196uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
197#endif
198
199// -------------------------- Misc ---------------- {{{1
200void ShowStatsAndAbort() {
201  __asan_print_accumulated_stats();
202  Die();
203}
204
205// ---------------------- mmap -------------------- {{{1
206// Reserve memory range [beg, end].
207static void ReserveShadowMemoryRange(uptr beg, uptr end) {
208  CHECK_EQ((beg % GetPageSizeCached()), 0);
209  CHECK_EQ(((end + 1) % GetPageSizeCached()), 0);
210  uptr size = end - beg + 1;
211  void *res = MmapFixedNoReserve(beg, size);
212  if (res != (void*)beg) {
213    Report("ReserveShadowMemoryRange failed while trying to map 0x%zx bytes. "
214           "Perhaps you're using ulimit -v\n", size);
215    Abort();
216  }
217}
218
219// --------------- LowLevelAllocateCallbac ---------- {{{1
220static void OnLowLevelAllocate(uptr ptr, uptr size) {
221  PoisonShadow(ptr, size, kAsanInternalHeapMagic);
222}
223
224// -------------------------- Run-time entry ------------------- {{{1
225// exported functions
226#define ASAN_REPORT_ERROR(type, is_write, size)                     \
227extern "C" NOINLINE INTERFACE_ATTRIBUTE                        \
228void __asan_report_ ## type ## size(uptr addr);                \
229void __asan_report_ ## type ## size(uptr addr) {               \
230  GET_CALLER_PC_BP_SP;                                              \
231  __asan_report_error(pc, bp, sp, addr, is_write, size);            \
232}
233
234ASAN_REPORT_ERROR(load, false, 1)
235ASAN_REPORT_ERROR(load, false, 2)
236ASAN_REPORT_ERROR(load, false, 4)
237ASAN_REPORT_ERROR(load, false, 8)
238ASAN_REPORT_ERROR(load, false, 16)
239ASAN_REPORT_ERROR(store, true, 1)
240ASAN_REPORT_ERROR(store, true, 2)
241ASAN_REPORT_ERROR(store, true, 4)
242ASAN_REPORT_ERROR(store, true, 8)
243ASAN_REPORT_ERROR(store, true, 16)
244
245#define ASAN_REPORT_ERROR_N(type, is_write)                    \
246extern "C" NOINLINE INTERFACE_ATTRIBUTE                        \
247void __asan_report_ ## type ## _n(uptr addr, uptr size);       \
248void __asan_report_ ## type ## _n(uptr addr, uptr size) {      \
249  GET_CALLER_PC_BP_SP;                                         \
250  __asan_report_error(pc, bp, sp, addr, is_write, size);       \
251}
252
253ASAN_REPORT_ERROR_N(load, false)
254ASAN_REPORT_ERROR_N(store, true)
255
256// Force the linker to keep the symbols for various ASan interface functions.
257// We want to keep those in the executable in order to let the instrumented
258// dynamic libraries access the symbol even if it is not used by the executable
259// itself. This should help if the build system is removing dead code at link
260// time.
261static NOINLINE void force_interface_symbols() {
262  volatile int fake_condition = 0;  // prevent dead condition elimination.
263  // __asan_report_* functions are noreturn, so we need a switch to prevent
264  // the compiler from removing any of them.
265  switch (fake_condition) {
266    case 1: __asan_report_load1(0); break;
267    case 2: __asan_report_load2(0); break;
268    case 3: __asan_report_load4(0); break;
269    case 4: __asan_report_load8(0); break;
270    case 5: __asan_report_load16(0); break;
271    case 6: __asan_report_store1(0); break;
272    case 7: __asan_report_store2(0); break;
273    case 8: __asan_report_store4(0); break;
274    case 9: __asan_report_store8(0); break;
275    case 10: __asan_report_store16(0); break;
276    case 12: __asan_register_globals(0, 0); break;
277    case 13: __asan_unregister_globals(0, 0); break;
278    case 14: __asan_set_death_callback(0); break;
279    case 15: __asan_set_error_report_callback(0); break;
280    case 16: __asan_handle_no_return(); break;
281    case 17: __asan_address_is_poisoned(0); break;
282    case 18: __asan_get_allocated_size(0); break;
283    case 19: __asan_get_current_allocated_bytes(); break;
284    case 20: __asan_get_estimated_allocated_size(0); break;
285    case 21: __asan_get_free_bytes(); break;
286    case 22: __asan_get_heap_size(); break;
287    case 23: __asan_get_ownership(0); break;
288    case 24: __asan_get_unmapped_bytes(); break;
289    case 25: __asan_poison_memory_region(0, 0); break;
290    case 26: __asan_unpoison_memory_region(0, 0); break;
291    case 27: __asan_set_error_exit_code(0); break;
292    case 28: __asan_stack_free(0, 0, 0); break;
293    case 29: __asan_stack_malloc(0, 0); break;
294    case 30: __asan_before_dynamic_init(0); break;
295    case 31: __asan_after_dynamic_init(); break;
296    case 32: __asan_poison_stack_memory(0, 0); break;
297    case 33: __asan_unpoison_stack_memory(0, 0); break;
298    case 34: __asan_region_is_poisoned(0, 0); break;
299    case 35: __asan_describe_address(0); break;
300  }
301}
302
303static void asan_atexit() {
304  Printf("AddressSanitizer exit stats:\n");
305  __asan_print_accumulated_stats();
306  // Print AsanMappingProfile.
307  for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
308    if (AsanMappingProfile[i] == 0) continue;
309    Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
310  }
311}
312
313static void InitializeHighMemEnd() {
314#if !ASAN_FIXED_MAPPING
315#if SANITIZER_WORDSIZE == 64
316# if defined(__powerpc64__)
317  // FIXME:
318  // On PowerPC64 we have two different address space layouts: 44- and 46-bit.
319  // We somehow need to figure our which one we are using now and choose
320  // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL.
321  // Note that with 'ulimit -s unlimited' the stack is moved away from the top
322  // of the address space, so simply checking the stack address is not enough.
323  kHighMemEnd = (1ULL << 44) - 1;  // 0x00000fffffffffffUL
324# else
325  kHighMemEnd = (1ULL << 47) - 1;  // 0x00007fffffffffffUL;
326# endif
327#else  // SANITIZER_WORDSIZE == 32
328  kHighMemEnd = (1ULL << 32) - 1;  // 0xffffffff;
329#endif  // SANITIZER_WORDSIZE
330#endif  // !ASAN_FIXED_MAPPING
331}
332
333static void ProtectGap(uptr a, uptr size) {
334  CHECK_EQ(a, (uptr)Mprotect(a, size));
335}
336
337static void PrintAddressSpaceLayout() {
338  Printf("|| `[%p, %p]` || HighMem    ||\n",
339         (void*)kHighMemBeg, (void*)kHighMemEnd);
340  Printf("|| `[%p, %p]` || HighShadow ||\n",
341         (void*)kHighShadowBeg, (void*)kHighShadowEnd);
342  if (kMidMemBeg) {
343    Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
344           (void*)kShadowGap3Beg, (void*)kShadowGap3End);
345    Printf("|| `[%p, %p]` || MidMem     ||\n",
346           (void*)kMidMemBeg, (void*)kMidMemEnd);
347    Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
348           (void*)kShadowGap2Beg, (void*)kShadowGap2End);
349    Printf("|| `[%p, %p]` || MidShadow  ||\n",
350           (void*)kMidShadowBeg, (void*)kMidShadowEnd);
351  }
352  Printf("|| `[%p, %p]` || ShadowGap  ||\n",
353         (void*)kShadowGapBeg, (void*)kShadowGapEnd);
354  if (kLowShadowBeg) {
355    Printf("|| `[%p, %p]` || LowShadow  ||\n",
356           (void*)kLowShadowBeg, (void*)kLowShadowEnd);
357    Printf("|| `[%p, %p]` || LowMem     ||\n",
358           (void*)kLowMemBeg, (void*)kLowMemEnd);
359  }
360  Printf("MemToShadow(shadow): %p %p %p %p",
361         (void*)MEM_TO_SHADOW(kLowShadowBeg),
362         (void*)MEM_TO_SHADOW(kLowShadowEnd),
363         (void*)MEM_TO_SHADOW(kHighShadowBeg),
364         (void*)MEM_TO_SHADOW(kHighShadowEnd));
365  if (kMidMemBeg) {
366    Printf(" %p %p",
367           (void*)MEM_TO_SHADOW(kMidShadowBeg),
368           (void*)MEM_TO_SHADOW(kMidShadowEnd));
369  }
370  Printf("\n");
371  Printf("red_zone=%zu\n", (uptr)flags()->redzone);
372  Printf("malloc_context_size=%zu\n", (uptr)flags()->malloc_context_size);
373
374  Printf("SHADOW_SCALE: %zx\n", (uptr)SHADOW_SCALE);
375  Printf("SHADOW_GRANULARITY: %zx\n", (uptr)SHADOW_GRANULARITY);
376  Printf("SHADOW_OFFSET: %zx\n", (uptr)SHADOW_OFFSET);
377  CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
378  if (kMidMemBeg)
379    CHECK(kMidShadowBeg > kLowShadowEnd &&
380          kMidMemBeg > kMidShadowEnd &&
381          kHighShadowBeg > kMidMemEnd);
382}
383
384}  // namespace __asan
385
386// ---------------------- Interface ---------------- {{{1
387using namespace __asan;  // NOLINT
388
389#if !SANITIZER_SUPPORTS_WEAK_HOOKS
390extern "C" {
391SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE
392const char* __asan_default_options() { return ""; }
393}  // extern "C"
394#endif
395
396int NOINLINE __asan_set_error_exit_code(int exit_code) {
397  int old = flags()->exitcode;
398  flags()->exitcode = exit_code;
399  return old;
400}
401
402void NOINLINE __asan_handle_no_return() {
403  int local_stack;
404  AsanThread *curr_thread = GetCurrentThread();
405  CHECK(curr_thread);
406  uptr PageSize = GetPageSizeCached();
407  uptr top = curr_thread->stack_top();
408  uptr bottom = ((uptr)&local_stack - PageSize) & ~(PageSize-1);
409  PoisonShadow(bottom, top - bottom, 0);
410}
411
412void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
413  death_callback = callback;
414}
415
416void __asan_init() {
417  if (asan_inited) return;
418  SanitizerToolName = "AddressSanitizer";
419  CHECK(!asan_init_is_running && "ASan init calls itself!");
420  asan_init_is_running = true;
421  InitializeHighMemEnd();
422
423  // Make sure we are not statically linked.
424  AsanDoesNotSupportStaticLinkage();
425
426  // Install tool-specific callbacks in sanitizer_common.
427  SetDieCallback(AsanDie);
428  SetCheckFailedCallback(AsanCheckFailed);
429  SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
430
431  // Check if external symbolizer is defined before parsing the flags.
432  asan_external_symbolizer = GetEnv("ASAN_SYMBOLIZER_PATH");
433  // Initialize flags. This must be done early, because most of the
434  // initialization steps look at flags().
435  const char *options = GetEnv("ASAN_OPTIONS");
436  InitializeFlags(flags(), options);
437  __sanitizer_set_report_path(flags()->log_path);
438
439  if (flags()->verbosity && options) {
440    Report("Parsed ASAN_OPTIONS: %s\n", options);
441  }
442
443  // Re-exec ourselves if we need to set additional env or command line args.
444  MaybeReexec();
445
446  // Setup internal allocator callback.
447  SetLowLevelAllocateCallback(OnLowLevelAllocate);
448
449  if (flags()->atexit) {
450    Atexit(asan_atexit);
451  }
452
453  // interceptors
454  InitializeAsanInterceptors();
455
456  ReplaceSystemMalloc();
457  ReplaceOperatorsNewAndDelete();
458
459  uptr shadow_start = kLowShadowBeg;
460  if (kLowShadowBeg) shadow_start -= GetMmapGranularity();
461  uptr shadow_end = kHighShadowEnd;
462  bool full_shadow_is_available =
463      MemoryRangeIsAvailable(shadow_start, shadow_end);
464
465#if SANITIZER_LINUX && defined(__x86_64__) && !ASAN_FIXED_MAPPING
466  if (!full_shadow_is_available) {
467    kMidMemBeg = kLowMemEnd < 0x3000000000ULL ? 0x3000000000ULL : 0;
468    kMidMemEnd = kLowMemEnd < 0x3000000000ULL ? 0x4fffffffffULL : 0;
469  }
470#endif
471
472  if (flags()->verbosity)
473    PrintAddressSpaceLayout();
474
475  if (flags()->disable_core) {
476    DisableCoreDumper();
477  }
478
479  if (full_shadow_is_available) {
480    // mmap the low shadow plus at least one page at the left.
481    if (kLowShadowBeg)
482      ReserveShadowMemoryRange(shadow_start, kLowShadowEnd);
483    // mmap the high shadow.
484    ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd);
485    // protect the gap.
486    ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
487  } else if (kMidMemBeg &&
488      MemoryRangeIsAvailable(shadow_start, kMidMemBeg - 1) &&
489      MemoryRangeIsAvailable(kMidMemEnd + 1, shadow_end)) {
490    CHECK(kLowShadowBeg != kLowShadowEnd);
491    // mmap the low shadow plus at least one page at the left.
492    ReserveShadowMemoryRange(shadow_start, kLowShadowEnd);
493    // mmap the mid shadow.
494    ReserveShadowMemoryRange(kMidShadowBeg, kMidShadowEnd);
495    // mmap the high shadow.
496    ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd);
497    // protect the gaps.
498    ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
499    ProtectGap(kShadowGap2Beg, kShadowGap2End - kShadowGap2Beg + 1);
500    ProtectGap(kShadowGap3Beg, kShadowGap3End - kShadowGap3Beg + 1);
501  } else {
502    Report("Shadow memory range interleaves with an existing memory mapping. "
503           "ASan cannot proceed correctly. ABORTING.\n");
504    DumpProcessMap();
505    Die();
506  }
507
508  InstallSignalHandlers();
509  // Start symbolizer process if necessary.
510  if (flags()->symbolize && asan_external_symbolizer &&
511      asan_external_symbolizer[0]) {
512    InitializeExternalSymbolizer(asan_external_symbolizer);
513  }
514
515  // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
516  // should be set to 1 prior to initializing the threads.
517  asan_inited = 1;
518  asan_init_is_running = false;
519
520  // Create main thread.
521  AsanTSDInit(AsanThread::TSDDtor);
522  AsanThread *main_thread = AsanThread::Create(0, 0);
523  CreateThreadContextArgs create_main_args = { main_thread, 0 };
524  u32 main_tid = asanThreadRegistry().CreateThread(
525      0, true, 0, &create_main_args);
526  CHECK_EQ(0, main_tid);
527  SetCurrentThread(main_thread);
528  main_thread->ThreadStart(GetPid());
529  force_interface_symbols();  // no-op.
530
531  InitializeAllocator();
532
533  if (flags()->verbosity) {
534    Report("AddressSanitizer Init done\n");
535  }
536}
537