1 //===-- asan_interceptors.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 // Intercept various libc functions.
12 //===----------------------------------------------------------------------===//
13 
14 #include "asan_interceptors.h"
15 #include "asan_allocator.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_suppressions.h"
23 #include "lsan/lsan_common.h"
24 #include "sanitizer_common/sanitizer_libc.h"
25 
26 // There is no general interception at all on Fuchsia.
27 // Only the functions in asan_interceptors_memintrinsics.cpp are
28 // really defined to replace libc functions.
29 #if !SANITIZER_FUCHSIA
30 
31 #  if SANITIZER_POSIX
32 #    include "sanitizer_common/sanitizer_posix.h"
33 #  endif
34 
35 #  if ASAN_INTERCEPT__UNWIND_RAISEEXCEPTION || \
36       ASAN_INTERCEPT__SJLJ_UNWIND_RAISEEXCEPTION
37 #    include <unwind.h>
38 #  endif
39 
40 #  if defined(__i386) && SANITIZER_LINUX
41 #    define ASAN_PTHREAD_CREATE_VERSION "GLIBC_2.1"
42 #  elif defined(__mips__) && SANITIZER_LINUX
43 #    define ASAN_PTHREAD_CREATE_VERSION "GLIBC_2.2"
44 #  endif
45 
46 namespace __asan {
47 
48 #define ASAN_READ_STRING_OF_LEN(ctx, s, len, n)                 \
49   ASAN_READ_RANGE((ctx), (s),                                   \
50     common_flags()->strict_string_checks ? (len) + 1 : (n))
51 
52 #define ASAN_READ_STRING(ctx, s, n)                             \
53   ASAN_READ_STRING_OF_LEN((ctx), (s), REAL(strlen)(s), (n))
54 
55 static inline uptr MaybeRealStrnlen(const char *s, uptr maxlen) {
56 #if SANITIZER_INTERCEPT_STRNLEN
57   if (REAL(strnlen)) {
58     return REAL(strnlen)(s, maxlen);
59   }
60 #endif
61   return internal_strnlen(s, maxlen);
62 }
63 
64 void SetThreadName(const char *name) {
65   AsanThread *t = GetCurrentThread();
66   if (t)
67     asanThreadRegistry().SetThreadName(t->tid(), name);
68 }
69 
70 int OnExit() {
71   if (CAN_SANITIZE_LEAKS && common_flags()->detect_leaks &&
72       __lsan::HasReportedLeaks()) {
73     return common_flags()->exitcode;
74   }
75   // FIXME: ask frontend whether we need to return failure.
76   return 0;
77 }
78 
79 } // namespace __asan
80 
81 // ---------------------- Wrappers ---------------- {{{1
82 using namespace __asan;
83 
84 DECLARE_REAL_AND_INTERCEPTOR(void *, malloc, uptr)
85 DECLARE_REAL_AND_INTERCEPTOR(void, free, void *)
86 
87 #define ASAN_INTERCEPTOR_ENTER(ctx, func)                                      \
88   AsanInterceptorContext _ctx = {#func};                                       \
89   ctx = (void *)&_ctx;                                                         \
90   (void) ctx;                                                                  \
91 
92 #define COMMON_INTERCEPT_FUNCTION(name) ASAN_INTERCEPT_FUNC(name)
93 #define COMMON_INTERCEPT_FUNCTION_VER(name, ver) \
94   ASAN_INTERCEPT_FUNC_VER(name, ver)
95 #define COMMON_INTERCEPT_FUNCTION_VER_UNVERSIONED_FALLBACK(name, ver) \
96   ASAN_INTERCEPT_FUNC_VER_UNVERSIONED_FALLBACK(name, ver)
97 #define COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ptr, size) \
98   ASAN_WRITE_RANGE(ctx, ptr, size)
99 #define COMMON_INTERCEPTOR_READ_RANGE(ctx, ptr, size) \
100   ASAN_READ_RANGE(ctx, ptr, size)
101 #define COMMON_INTERCEPTOR_ENTER(ctx, func, ...)                               \
102   ASAN_INTERCEPTOR_ENTER(ctx, func);                                           \
103   do {                                                                         \
104     if (asan_init_is_running)                                                  \
105       return REAL(func)(__VA_ARGS__);                                          \
106     if (SANITIZER_MAC && UNLIKELY(!asan_inited))                               \
107       return REAL(func)(__VA_ARGS__);                                          \
108     ENSURE_ASAN_INITED();                                                      \
109   } while (false)
110 #define COMMON_INTERCEPTOR_DIR_ACQUIRE(ctx, path) \
111   do {                                            \
112   } while (false)
113 #define COMMON_INTERCEPTOR_FD_ACQUIRE(ctx, fd) \
114   do {                                         \
115   } while (false)
116 #define COMMON_INTERCEPTOR_FD_RELEASE(ctx, fd) \
117   do {                                         \
118   } while (false)
119 #define COMMON_INTERCEPTOR_FD_SOCKET_ACCEPT(ctx, fd, newfd) \
120   do {                                                      \
121   } while (false)
122 #define COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name) SetThreadName(name)
123 // Should be asanThreadRegistry().SetThreadNameByUserId(thread, name)
124 // But asan does not remember UserId's for threads (pthread_t);
125 // and remembers all ever existed threads, so the linear search by UserId
126 // can be slow.
127 #define COMMON_INTERCEPTOR_SET_PTHREAD_NAME(ctx, thread, name) \
128   do {                                                         \
129   } while (false)
130 #define COMMON_INTERCEPTOR_BLOCK_REAL(name) REAL(name)
131 // Strict init-order checking is dlopen-hostile:
132 // https://github.com/google/sanitizers/issues/178
133 #define COMMON_INTERCEPTOR_ON_DLOPEN(filename, flag)                           \
134   do {                                                                         \
135     if (flags()->strict_init_order)                                            \
136       StopInitOrderChecking();                                                 \
137     CheckNoDeepBind(filename, flag);                                           \
138   } while (false)
139 #define COMMON_INTERCEPTOR_ON_EXIT(ctx) OnExit()
140 #define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, handle)
141 #define COMMON_INTERCEPTOR_LIBRARY_UNLOADED()
142 #define COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED (!asan_inited)
143 #define COMMON_INTERCEPTOR_GET_TLS_RANGE(begin, end)                           \
144   if (AsanThread *t = GetCurrentThread()) {                                    \
145     *begin = t->tls_begin();                                                   \
146     *end = t->tls_end();                                                       \
147   } else {                                                                     \
148     *begin = *end = 0;                                                         \
149   }
150 
151 #define COMMON_INTERCEPTOR_MEMMOVE_IMPL(ctx, to, from, size) \
152   do {                                                       \
153     ASAN_INTERCEPTOR_ENTER(ctx, memmove);                    \
154     ASAN_MEMMOVE_IMPL(ctx, to, from, size);                  \
155   } while (false)
156 
157 #define COMMON_INTERCEPTOR_MEMCPY_IMPL(ctx, to, from, size) \
158   do {                                                      \
159     ASAN_INTERCEPTOR_ENTER(ctx, memcpy);                    \
160     ASAN_MEMCPY_IMPL(ctx, to, from, size);                  \
161   } while (false)
162 
163 #define COMMON_INTERCEPTOR_MEMSET_IMPL(ctx, block, c, size) \
164   do {                                                      \
165     ASAN_INTERCEPTOR_ENTER(ctx, memset);                    \
166     ASAN_MEMSET_IMPL(ctx, block, c, size);                  \
167   } while (false)
168 
169 #if CAN_SANITIZE_LEAKS
170 #define COMMON_INTERCEPTOR_STRERROR()                       \
171   __lsan::ScopedInterceptorDisabler disabler
172 #endif
173 
174 #include "sanitizer_common/sanitizer_common_interceptors.inc"
175 #include "sanitizer_common/sanitizer_signal_interceptors.inc"
176 
177 // Syscall interceptors don't have contexts, we don't support suppressions
178 // for them.
179 #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) ASAN_READ_RANGE(nullptr, p, s)
180 #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) ASAN_WRITE_RANGE(nullptr, p, s)
181 #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \
182   do {                                       \
183     (void)(p);                               \
184     (void)(s);                               \
185   } while (false)
186 #define COMMON_SYSCALL_POST_WRITE_RANGE(p, s) \
187   do {                                        \
188     (void)(p);                                \
189     (void)(s);                                \
190   } while (false)
191 #include "sanitizer_common/sanitizer_common_syscalls.inc"
192 #include "sanitizer_common/sanitizer_syscalls_netbsd.inc"
193 
194 #if ASAN_INTERCEPT_PTHREAD_CREATE
195 static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
196   AsanThread *t = (AsanThread *)arg;
197   SetCurrentThread(t);
198   return t->ThreadStart(GetTid());
199 }
200 
201 INTERCEPTOR(int, pthread_create, void *thread,
202     void *attr, void *(*start_routine)(void*), void *arg) {
203   EnsureMainThreadIDIsCorrect();
204   // Strict init-order checking is thread-hostile.
205   if (flags()->strict_init_order)
206     StopInitOrderChecking();
207   GET_STACK_TRACE_THREAD;
208   int detached = 0;
209   if (attr)
210     REAL(pthread_attr_getdetachstate)(attr, &detached);
211 
212   u32 current_tid = GetCurrentTidOrInvalid();
213   AsanThread *t =
214       AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
215 
216   int result;
217   {
218     // Ignore all allocations made by pthread_create: thread stack/TLS may be
219     // stored by pthread for future reuse even after thread destruction, and
220     // the linked list it's stored in doesn't even hold valid pointers to the
221     // objects, the latter are calculated by obscure pointer arithmetic.
222 #if CAN_SANITIZE_LEAKS
223     __lsan::ScopedInterceptorDisabler disabler;
224 #endif
225     result = REAL(pthread_create)(thread, attr, asan_thread_start, t);
226   }
227   if (result != 0) {
228     // If the thread didn't start delete the AsanThread to avoid leaking it.
229     // Note AsanThreadContexts never get destroyed so the AsanThreadContext
230     // that was just created for the AsanThread is wasted.
231     t->Destroy();
232   }
233   return result;
234 }
235 
236 INTERCEPTOR(int, pthread_join, void *t, void **arg) {
237   return real_pthread_join(t, arg);
238 }
239 
240 DEFINE_REAL_PTHREAD_FUNCTIONS
241 #endif  // ASAN_INTERCEPT_PTHREAD_CREATE
242 
243 #if ASAN_INTERCEPT_SWAPCONTEXT
244 static void ClearShadowMemoryForContextStack(uptr stack, uptr ssize) {
245   // Align to page size.
246   uptr PageSize = GetPageSizeCached();
247   uptr bottom = stack & ~(PageSize - 1);
248   ssize += stack - bottom;
249   ssize = RoundUpTo(ssize, PageSize);
250   static const uptr kMaxSaneContextStackSize = 1 << 22;  // 4 Mb
251   if (AddrIsInMem(bottom) && ssize && ssize <= kMaxSaneContextStackSize) {
252     PoisonShadow(bottom, ssize, 0);
253   }
254 }
255 
256 INTERCEPTOR(int, swapcontext, struct ucontext_t *oucp,
257             struct ucontext_t *ucp) {
258   static bool reported_warning = false;
259   if (!reported_warning) {
260     Report("WARNING: ASan doesn't fully support makecontext/swapcontext "
261            "functions and may produce false positives in some cases!\n");
262     reported_warning = true;
263   }
264   // Clear shadow memory for new context (it may share stack
265   // with current context).
266   uptr stack, ssize;
267   ReadContextStack(ucp, &stack, &ssize);
268   ClearShadowMemoryForContextStack(stack, ssize);
269 #if __has_attribute(__indirect_return__) && \
270     (defined(__x86_64__) || defined(__i386__))
271   int (*real_swapcontext)(struct ucontext_t *, struct ucontext_t *)
272     __attribute__((__indirect_return__))
273     = REAL(swapcontext);
274   int res = real_swapcontext(oucp, ucp);
275 #else
276   int res = REAL(swapcontext)(oucp, ucp);
277 #endif
278   // swapcontext technically does not return, but program may swap context to
279   // "oucp" later, that would look as if swapcontext() returned 0.
280   // We need to clear shadow for ucp once again, as it may be in arbitrary
281   // state.
282   ClearShadowMemoryForContextStack(stack, ssize);
283   return res;
284 }
285 #endif  // ASAN_INTERCEPT_SWAPCONTEXT
286 
287 #if SANITIZER_NETBSD
288 #define longjmp __longjmp14
289 #define siglongjmp __siglongjmp14
290 #endif
291 
292 INTERCEPTOR(void, longjmp, void *env, int val) {
293   __asan_handle_no_return();
294   REAL(longjmp)(env, val);
295 }
296 
297 #if ASAN_INTERCEPT__LONGJMP
298 INTERCEPTOR(void, _longjmp, void *env, int val) {
299   __asan_handle_no_return();
300   REAL(_longjmp)(env, val);
301 }
302 #endif
303 
304 #if ASAN_INTERCEPT___LONGJMP_CHK
305 INTERCEPTOR(void, __longjmp_chk, void *env, int val) {
306   __asan_handle_no_return();
307   REAL(__longjmp_chk)(env, val);
308 }
309 #endif
310 
311 #if ASAN_INTERCEPT_SIGLONGJMP
312 INTERCEPTOR(void, siglongjmp, void *env, int val) {
313   __asan_handle_no_return();
314   REAL(siglongjmp)(env, val);
315 }
316 #endif
317 
318 #if ASAN_INTERCEPT___CXA_THROW
319 INTERCEPTOR(void, __cxa_throw, void *a, void *b, void *c) {
320   CHECK(REAL(__cxa_throw));
321   __asan_handle_no_return();
322   REAL(__cxa_throw)(a, b, c);
323 }
324 #endif
325 
326 #if ASAN_INTERCEPT___CXA_RETHROW_PRIMARY_EXCEPTION
327 INTERCEPTOR(void, __cxa_rethrow_primary_exception, void *a) {
328   CHECK(REAL(__cxa_rethrow_primary_exception));
329   __asan_handle_no_return();
330   REAL(__cxa_rethrow_primary_exception)(a);
331 }
332 #endif
333 
334 #if ASAN_INTERCEPT__UNWIND_RAISEEXCEPTION
335 INTERCEPTOR(_Unwind_Reason_Code, _Unwind_RaiseException,
336             _Unwind_Exception *object) {
337   CHECK(REAL(_Unwind_RaiseException));
338   __asan_handle_no_return();
339   return REAL(_Unwind_RaiseException)(object);
340 }
341 #endif
342 
343 #if ASAN_INTERCEPT__SJLJ_UNWIND_RAISEEXCEPTION
344 INTERCEPTOR(_Unwind_Reason_Code, _Unwind_SjLj_RaiseException,
345             _Unwind_Exception *object) {
346   CHECK(REAL(_Unwind_SjLj_RaiseException));
347   __asan_handle_no_return();
348   return REAL(_Unwind_SjLj_RaiseException)(object);
349 }
350 #endif
351 
352 #if ASAN_INTERCEPT_INDEX
353 # if ASAN_USE_ALIAS_ATTRIBUTE_FOR_INDEX
354 INTERCEPTOR(char*, index, const char *string, int c)
355   ALIAS(WRAPPER_NAME(strchr));
356 # else
357 #  if SANITIZER_MAC
358 DECLARE_REAL(char*, index, const char *string, int c)
359 OVERRIDE_FUNCTION(index, strchr);
360 #  else
361 DEFINE_REAL(char*, index, const char *string, int c)
362 #  endif
363 # endif
364 #endif  // ASAN_INTERCEPT_INDEX
365 
366 // For both strcat() and strncat() we need to check the validity of |to|
367 // argument irrespective of the |from| length.
368   INTERCEPTOR(char *, strcat, char *to, const char *from) {
369     void *ctx;
370     ASAN_INTERCEPTOR_ENTER(ctx, strcat);
371     ENSURE_ASAN_INITED();
372     if (flags()->replace_str) {
373       uptr from_length = REAL(strlen)(from);
374       ASAN_READ_RANGE(ctx, from, from_length + 1);
375       uptr to_length = REAL(strlen)(to);
376       ASAN_READ_STRING_OF_LEN(ctx, to, to_length, to_length);
377       ASAN_WRITE_RANGE(ctx, to + to_length, from_length + 1);
378       // If the copying actually happens, the |from| string should not overlap
379       // with the resulting string starting at |to|, which has a length of
380       // to_length + from_length + 1.
381       if (from_length > 0) {
382         CHECK_RANGES_OVERLAP("strcat", to, from_length + to_length + 1, from,
383                              from_length + 1);
384       }
385     }
386     return REAL(strcat)(to, from);
387   }
388 
389 INTERCEPTOR(char*, strncat, char *to, const char *from, uptr size) {
390   void *ctx;
391   ASAN_INTERCEPTOR_ENTER(ctx, strncat);
392   ENSURE_ASAN_INITED();
393   if (flags()->replace_str) {
394     uptr from_length = MaybeRealStrnlen(from, size);
395     uptr copy_length = Min(size, from_length + 1);
396     ASAN_READ_RANGE(ctx, from, copy_length);
397     uptr to_length = REAL(strlen)(to);
398     ASAN_READ_STRING_OF_LEN(ctx, to, to_length, to_length);
399     ASAN_WRITE_RANGE(ctx, to + to_length, from_length + 1);
400     if (from_length > 0) {
401       CHECK_RANGES_OVERLAP("strncat", to, to_length + copy_length + 1,
402                            from, copy_length);
403     }
404   }
405   return REAL(strncat)(to, from, size);
406 }
407 
408 INTERCEPTOR(char *, strcpy, char *to, const char *from) {
409   void *ctx;
410   ASAN_INTERCEPTOR_ENTER(ctx, strcpy);
411 #if SANITIZER_MAC
412   if (UNLIKELY(!asan_inited))
413     return REAL(strcpy)(to, from);
414 #endif
415   // strcpy is called from malloc_default_purgeable_zone()
416   // in __asan::ReplaceSystemAlloc() on Mac.
417   if (asan_init_is_running) {
418     return REAL(strcpy)(to, from);
419   }
420   ENSURE_ASAN_INITED();
421   if (flags()->replace_str) {
422     uptr from_size = REAL(strlen)(from) + 1;
423     CHECK_RANGES_OVERLAP("strcpy", to, from_size, from, from_size);
424     ASAN_READ_RANGE(ctx, from, from_size);
425     ASAN_WRITE_RANGE(ctx, to, from_size);
426   }
427   return REAL(strcpy)(to, from);
428 }
429 
430 INTERCEPTOR(char*, strdup, const char *s) {
431   void *ctx;
432   ASAN_INTERCEPTOR_ENTER(ctx, strdup);
433   if (UNLIKELY(!asan_inited)) return internal_strdup(s);
434   ENSURE_ASAN_INITED();
435   uptr length = REAL(strlen)(s);
436   if (flags()->replace_str) {
437     ASAN_READ_RANGE(ctx, s, length + 1);
438   }
439   GET_STACK_TRACE_MALLOC;
440   void *new_mem = asan_malloc(length + 1, &stack);
441   REAL(memcpy)(new_mem, s, length + 1);
442   return reinterpret_cast<char*>(new_mem);
443 }
444 
445 #if ASAN_INTERCEPT___STRDUP
446 INTERCEPTOR(char*, __strdup, const char *s) {
447   void *ctx;
448   ASAN_INTERCEPTOR_ENTER(ctx, strdup);
449   if (UNLIKELY(!asan_inited)) return internal_strdup(s);
450   ENSURE_ASAN_INITED();
451   uptr length = REAL(strlen)(s);
452   if (flags()->replace_str) {
453     ASAN_READ_RANGE(ctx, s, length + 1);
454   }
455   GET_STACK_TRACE_MALLOC;
456   void *new_mem = asan_malloc(length + 1, &stack);
457   REAL(memcpy)(new_mem, s, length + 1);
458   return reinterpret_cast<char*>(new_mem);
459 }
460 #endif // ASAN_INTERCEPT___STRDUP
461 
462 INTERCEPTOR(char*, strncpy, char *to, const char *from, uptr size) {
463   void *ctx;
464   ASAN_INTERCEPTOR_ENTER(ctx, strncpy);
465   ENSURE_ASAN_INITED();
466   if (flags()->replace_str) {
467     uptr from_size = Min(size, MaybeRealStrnlen(from, size) + 1);
468     CHECK_RANGES_OVERLAP("strncpy", to, from_size, from, from_size);
469     ASAN_READ_RANGE(ctx, from, from_size);
470     ASAN_WRITE_RANGE(ctx, to, size);
471   }
472   return REAL(strncpy)(to, from, size);
473 }
474 
475 INTERCEPTOR(long, strtol, const char *nptr, char **endptr, int base) {
476   void *ctx;
477   ASAN_INTERCEPTOR_ENTER(ctx, strtol);
478   ENSURE_ASAN_INITED();
479   if (!flags()->replace_str) {
480     return REAL(strtol)(nptr, endptr, base);
481   }
482   char *real_endptr;
483   long result = REAL(strtol)(nptr, &real_endptr, base);
484   StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
485   return result;
486 }
487 
488 INTERCEPTOR(int, atoi, const char *nptr) {
489   void *ctx;
490   ASAN_INTERCEPTOR_ENTER(ctx, atoi);
491 #if SANITIZER_MAC
492   if (UNLIKELY(!asan_inited)) return REAL(atoi)(nptr);
493 #endif
494   ENSURE_ASAN_INITED();
495   if (!flags()->replace_str) {
496     return REAL(atoi)(nptr);
497   }
498   char *real_endptr;
499   // "man atoi" tells that behavior of atoi(nptr) is the same as
500   // strtol(nptr, 0, 10), i.e. it sets errno to ERANGE if the
501   // parsed integer can't be stored in *long* type (even if it's
502   // different from int). So, we just imitate this behavior.
503   int result = REAL(strtol)(nptr, &real_endptr, 10);
504   FixRealStrtolEndptr(nptr, &real_endptr);
505   ASAN_READ_STRING(ctx, nptr, (real_endptr - nptr) + 1);
506   return result;
507 }
508 
509 INTERCEPTOR(long, atol, const char *nptr) {
510   void *ctx;
511   ASAN_INTERCEPTOR_ENTER(ctx, atol);
512 #if SANITIZER_MAC
513   if (UNLIKELY(!asan_inited)) return REAL(atol)(nptr);
514 #endif
515   ENSURE_ASAN_INITED();
516   if (!flags()->replace_str) {
517     return REAL(atol)(nptr);
518   }
519   char *real_endptr;
520   long result = REAL(strtol)(nptr, &real_endptr, 10);
521   FixRealStrtolEndptr(nptr, &real_endptr);
522   ASAN_READ_STRING(ctx, nptr, (real_endptr - nptr) + 1);
523   return result;
524 }
525 
526 #if ASAN_INTERCEPT_ATOLL_AND_STRTOLL
527 INTERCEPTOR(long long, strtoll, const char *nptr, char **endptr, int base) {
528   void *ctx;
529   ASAN_INTERCEPTOR_ENTER(ctx, strtoll);
530   ENSURE_ASAN_INITED();
531   if (!flags()->replace_str) {
532     return REAL(strtoll)(nptr, endptr, base);
533   }
534   char *real_endptr;
535   long long result = REAL(strtoll)(nptr, &real_endptr, base);
536   StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
537   return result;
538 }
539 
540 INTERCEPTOR(long long, atoll, const char *nptr) {
541   void *ctx;
542   ASAN_INTERCEPTOR_ENTER(ctx, atoll);
543   ENSURE_ASAN_INITED();
544   if (!flags()->replace_str) {
545     return REAL(atoll)(nptr);
546   }
547   char *real_endptr;
548   long long result = REAL(strtoll)(nptr, &real_endptr, 10);
549   FixRealStrtolEndptr(nptr, &real_endptr);
550   ASAN_READ_STRING(ctx, nptr, (real_endptr - nptr) + 1);
551   return result;
552 }
553 #endif  // ASAN_INTERCEPT_ATOLL_AND_STRTOLL
554 
555 #if ASAN_INTERCEPT___CXA_ATEXIT || ASAN_INTERCEPT_ATEXIT
556 static void AtCxaAtexit(void *unused) {
557   (void)unused;
558   StopInitOrderChecking();
559 }
560 #endif
561 
562 #if ASAN_INTERCEPT___CXA_ATEXIT
563 INTERCEPTOR(int, __cxa_atexit, void (*func)(void *), void *arg,
564             void *dso_handle) {
565 #if SANITIZER_MAC
566   if (UNLIKELY(!asan_inited)) return REAL(__cxa_atexit)(func, arg, dso_handle);
567 #endif
568   ENSURE_ASAN_INITED();
569 #if CAN_SANITIZE_LEAKS
570   __lsan::ScopedInterceptorDisabler disabler;
571 #endif
572   int res = REAL(__cxa_atexit)(func, arg, dso_handle);
573   REAL(__cxa_atexit)(AtCxaAtexit, nullptr, nullptr);
574   return res;
575 }
576 #endif  // ASAN_INTERCEPT___CXA_ATEXIT
577 
578 #if ASAN_INTERCEPT_ATEXIT
579 INTERCEPTOR(int, atexit, void (*func)()) {
580   ENSURE_ASAN_INITED();
581 #if CAN_SANITIZE_LEAKS
582   __lsan::ScopedInterceptorDisabler disabler;
583 #endif
584   // Avoid calling real atexit as it is unrechable on at least on Linux.
585   int res = REAL(__cxa_atexit)((void (*)(void *a))func, nullptr, nullptr);
586   REAL(__cxa_atexit)(AtCxaAtexit, nullptr, nullptr);
587   return res;
588 }
589 #endif
590 
591 #if ASAN_INTERCEPT_PTHREAD_ATFORK
592 extern "C" {
593 extern int _pthread_atfork(void (*prepare)(), void (*parent)(),
594                            void (*child)());
595 };
596 
597 INTERCEPTOR(int, pthread_atfork, void (*prepare)(), void (*parent)(),
598             void (*child)()) {
599 #if CAN_SANITIZE_LEAKS
600   __lsan::ScopedInterceptorDisabler disabler;
601 #endif
602   // REAL(pthread_atfork) cannot be called due to symbol indirections at least
603   // on NetBSD
604   return _pthread_atfork(prepare, parent, child);
605 }
606 #endif
607 
608 #if ASAN_INTERCEPT_VFORK
609 DEFINE_REAL(int, vfork)
610 DECLARE_EXTERN_INTERCEPTOR_AND_WRAPPER(int, vfork)
611 #endif
612 
613 // ---------------------- InitializeAsanInterceptors ---------------- {{{1
614 namespace __asan {
615 void InitializeAsanInterceptors() {
616   static bool was_called_once;
617   CHECK(!was_called_once);
618   was_called_once = true;
619   InitializeCommonInterceptors();
620   InitializeSignalInterceptors();
621 
622   // Intercept str* functions.
623   ASAN_INTERCEPT_FUNC(strcat);
624   ASAN_INTERCEPT_FUNC(strcpy);
625   ASAN_INTERCEPT_FUNC(strncat);
626   ASAN_INTERCEPT_FUNC(strncpy);
627   ASAN_INTERCEPT_FUNC(strdup);
628 #if ASAN_INTERCEPT___STRDUP
629   ASAN_INTERCEPT_FUNC(__strdup);
630 #endif
631 #if ASAN_INTERCEPT_INDEX && ASAN_USE_ALIAS_ATTRIBUTE_FOR_INDEX
632   ASAN_INTERCEPT_FUNC(index);
633 #endif
634 
635   ASAN_INTERCEPT_FUNC(atoi);
636   ASAN_INTERCEPT_FUNC(atol);
637   ASAN_INTERCEPT_FUNC(strtol);
638 #if ASAN_INTERCEPT_ATOLL_AND_STRTOLL
639   ASAN_INTERCEPT_FUNC(atoll);
640   ASAN_INTERCEPT_FUNC(strtoll);
641 #endif
642 
643   // Intecept jump-related functions.
644   ASAN_INTERCEPT_FUNC(longjmp);
645 
646 #if ASAN_INTERCEPT_SWAPCONTEXT
647   ASAN_INTERCEPT_FUNC(swapcontext);
648 #endif
649 #if ASAN_INTERCEPT__LONGJMP
650   ASAN_INTERCEPT_FUNC(_longjmp);
651 #endif
652 #if ASAN_INTERCEPT___LONGJMP_CHK
653   ASAN_INTERCEPT_FUNC(__longjmp_chk);
654 #endif
655 #if ASAN_INTERCEPT_SIGLONGJMP
656   ASAN_INTERCEPT_FUNC(siglongjmp);
657 #endif
658 
659   // Intercept exception handling functions.
660 #if ASAN_INTERCEPT___CXA_THROW
661   ASAN_INTERCEPT_FUNC(__cxa_throw);
662 #endif
663 #if ASAN_INTERCEPT___CXA_RETHROW_PRIMARY_EXCEPTION
664   ASAN_INTERCEPT_FUNC(__cxa_rethrow_primary_exception);
665 #endif
666   // Indirectly intercept std::rethrow_exception.
667 #if ASAN_INTERCEPT__UNWIND_RAISEEXCEPTION
668   INTERCEPT_FUNCTION(_Unwind_RaiseException);
669 #endif
670   // Indirectly intercept std::rethrow_exception.
671 #if ASAN_INTERCEPT__UNWIND_SJLJ_RAISEEXCEPTION
672   INTERCEPT_FUNCTION(_Unwind_SjLj_RaiseException);
673 #endif
674 
675   // Intercept threading-related functions
676 #if ASAN_INTERCEPT_PTHREAD_CREATE
677 // TODO: this should probably have an unversioned fallback for newer arches?
678 #if defined(ASAN_PTHREAD_CREATE_VERSION)
679   ASAN_INTERCEPT_FUNC_VER(pthread_create, ASAN_PTHREAD_CREATE_VERSION);
680 #else
681   ASAN_INTERCEPT_FUNC(pthread_create);
682 #endif
683   ASAN_INTERCEPT_FUNC(pthread_join);
684 #endif
685 
686   // Intercept atexit function.
687 #if ASAN_INTERCEPT___CXA_ATEXIT
688   ASAN_INTERCEPT_FUNC(__cxa_atexit);
689 #endif
690 
691 #if ASAN_INTERCEPT_ATEXIT
692   ASAN_INTERCEPT_FUNC(atexit);
693 #endif
694 
695 #if ASAN_INTERCEPT_PTHREAD_ATFORK
696   ASAN_INTERCEPT_FUNC(pthread_atfork);
697 #endif
698 
699 #if ASAN_INTERCEPT_VFORK
700   ASAN_INTERCEPT_FUNC(vfork);
701 #endif
702 
703   InitializePlatformInterceptors();
704 
705   VReport(1, "AddressSanitizer: libc interceptors initialized\n");
706 }
707 
708 } // namespace __asan
709 
710 #endif  // !SANITIZER_FUCHSIA
711