xref: /freebsd/contrib/llvm-project/compiler-rt/lib/asan/asan_interceptors.cpp (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
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), internal_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_DLOPEN(filename, flag) \
134     ({                                              \
135       if (flags()->strict_init_order)               \
136         StopInitOrderChecking();                    \
137       CheckNoDeepBind(filename, flag);              \
138       REAL(dlopen)(filename, flag);                 \
139     })
140 #  define COMMON_INTERCEPTOR_ON_EXIT(ctx) OnExit()
141 #  define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, handle)
142 #  define COMMON_INTERCEPTOR_LIBRARY_UNLOADED()
143 #  define COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED (!asan_inited)
144 #  define COMMON_INTERCEPTOR_GET_TLS_RANGE(begin, end) \
145     if (AsanThread *t = GetCurrentThread()) {          \
146       *begin = t->tls_begin();                         \
147       *end = t->tls_end();                             \
148     } else {                                           \
149       *begin = *end = 0;                               \
150     }
151 
152 #define COMMON_INTERCEPTOR_MEMMOVE_IMPL(ctx, to, from, size) \
153   do {                                                       \
154     ASAN_INTERCEPTOR_ENTER(ctx, memmove);                    \
155     ASAN_MEMMOVE_IMPL(ctx, to, from, size);                  \
156   } while (false)
157 
158 #define COMMON_INTERCEPTOR_MEMCPY_IMPL(ctx, to, from, size) \
159   do {                                                      \
160     ASAN_INTERCEPTOR_ENTER(ctx, memcpy);                    \
161     ASAN_MEMCPY_IMPL(ctx, to, from, size);                  \
162   } while (false)
163 
164 #define COMMON_INTERCEPTOR_MEMSET_IMPL(ctx, block, c, size) \
165   do {                                                      \
166     ASAN_INTERCEPTOR_ENTER(ctx, memset);                    \
167     ASAN_MEMSET_IMPL(ctx, block, c, size);                  \
168   } while (false)
169 
170 #if CAN_SANITIZE_LEAKS
171 #define COMMON_INTERCEPTOR_STRERROR()                       \
172   __lsan::ScopedInterceptorDisabler disabler
173 #endif
174 
175 #include "sanitizer_common/sanitizer_common_interceptors.inc"
176 #include "sanitizer_common/sanitizer_signal_interceptors.inc"
177 
178 // Syscall interceptors don't have contexts, we don't support suppressions
179 // for them.
180 #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) ASAN_READ_RANGE(nullptr, p, s)
181 #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) ASAN_WRITE_RANGE(nullptr, p, s)
182 #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \
183   do {                                       \
184     (void)(p);                               \
185     (void)(s);                               \
186   } while (false)
187 #define COMMON_SYSCALL_POST_WRITE_RANGE(p, s) \
188   do {                                        \
189     (void)(p);                                \
190     (void)(s);                                \
191   } while (false)
192 #include "sanitizer_common/sanitizer_common_syscalls.inc"
193 #include "sanitizer_common/sanitizer_syscalls_netbsd.inc"
194 
195 #if ASAN_INTERCEPT_PTHREAD_CREATE
196 static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
197   AsanThread *t = (AsanThread *)arg;
198   SetCurrentThread(t);
199   return t->ThreadStart(GetTid());
200 }
201 
202 INTERCEPTOR(int, pthread_create, void *thread,
203     void *attr, void *(*start_routine)(void*), void *arg) {
204   EnsureMainThreadIDIsCorrect();
205   // Strict init-order checking is thread-hostile.
206   if (flags()->strict_init_order)
207     StopInitOrderChecking();
208   GET_STACK_TRACE_THREAD;
209   int detached = 0;
210   if (attr)
211     REAL(pthread_attr_getdetachstate)(attr, &detached);
212 
213   u32 current_tid = GetCurrentTidOrInvalid();
214   AsanThread *t =
215       AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
216 
217   int result;
218   {
219     // Ignore all allocations made by pthread_create: thread stack/TLS may be
220     // stored by pthread for future reuse even after thread destruction, and
221     // the linked list it's stored in doesn't even hold valid pointers to the
222     // objects, the latter are calculated by obscure pointer arithmetic.
223 #if CAN_SANITIZE_LEAKS
224     __lsan::ScopedInterceptorDisabler disabler;
225 #endif
226     result = REAL(pthread_create)(thread, attr, asan_thread_start, t);
227   }
228   if (result != 0) {
229     // If the thread didn't start delete the AsanThread to avoid leaking it.
230     // Note AsanThreadContexts never get destroyed so the AsanThreadContext
231     // that was just created for the AsanThread is wasted.
232     t->Destroy();
233   }
234   return result;
235 }
236 
237 INTERCEPTOR(int, pthread_join, void *t, void **arg) {
238   return real_pthread_join(t, arg);
239 }
240 
241 DEFINE_REAL_PTHREAD_FUNCTIONS
242 #endif  // ASAN_INTERCEPT_PTHREAD_CREATE
243 
244 #if ASAN_INTERCEPT_SWAPCONTEXT
245 static void ClearShadowMemoryForContextStack(uptr stack, uptr ssize) {
246   // Align to page size.
247   uptr PageSize = GetPageSizeCached();
248   uptr bottom = stack & ~(PageSize - 1);
249   ssize += stack - bottom;
250   ssize = RoundUpTo(ssize, PageSize);
251   static const uptr kMaxSaneContextStackSize = 1 << 22;  // 4 Mb
252   if (AddrIsInMem(bottom) && ssize && ssize <= kMaxSaneContextStackSize) {
253     PoisonShadow(bottom, ssize, 0);
254   }
255 }
256 
257 INTERCEPTOR(int, swapcontext, struct ucontext_t *oucp,
258             struct ucontext_t *ucp) {
259   static bool reported_warning = false;
260   if (!reported_warning) {
261     Report("WARNING: ASan doesn't fully support makecontext/swapcontext "
262            "functions and may produce false positives in some cases!\n");
263     reported_warning = true;
264   }
265   // Clear shadow memory for new context (it may share stack
266   // with current context).
267   uptr stack, ssize;
268   ReadContextStack(ucp, &stack, &ssize);
269   ClearShadowMemoryForContextStack(stack, ssize);
270 #if __has_attribute(__indirect_return__) && \
271     (defined(__x86_64__) || defined(__i386__))
272   int (*real_swapcontext)(struct ucontext_t *, struct ucontext_t *)
273     __attribute__((__indirect_return__))
274     = REAL(swapcontext);
275   int res = real_swapcontext(oucp, ucp);
276 #else
277   int res = REAL(swapcontext)(oucp, ucp);
278 #endif
279   // swapcontext technically does not return, but program may swap context to
280   // "oucp" later, that would look as if swapcontext() returned 0.
281   // We need to clear shadow for ucp once again, as it may be in arbitrary
282   // state.
283   ClearShadowMemoryForContextStack(stack, ssize);
284   return res;
285 }
286 #endif  // ASAN_INTERCEPT_SWAPCONTEXT
287 
288 #if SANITIZER_NETBSD
289 #define longjmp __longjmp14
290 #define siglongjmp __siglongjmp14
291 #endif
292 
293 INTERCEPTOR(void, longjmp, void *env, int val) {
294   __asan_handle_no_return();
295   REAL(longjmp)(env, val);
296 }
297 
298 #if ASAN_INTERCEPT__LONGJMP
299 INTERCEPTOR(void, _longjmp, void *env, int val) {
300   __asan_handle_no_return();
301   REAL(_longjmp)(env, val);
302 }
303 #endif
304 
305 #if ASAN_INTERCEPT___LONGJMP_CHK
306 INTERCEPTOR(void, __longjmp_chk, void *env, int val) {
307   __asan_handle_no_return();
308   REAL(__longjmp_chk)(env, val);
309 }
310 #endif
311 
312 #if ASAN_INTERCEPT_SIGLONGJMP
313 INTERCEPTOR(void, siglongjmp, void *env, int val) {
314   __asan_handle_no_return();
315   REAL(siglongjmp)(env, val);
316 }
317 #endif
318 
319 #if ASAN_INTERCEPT___CXA_THROW
320 INTERCEPTOR(void, __cxa_throw, void *a, void *b, void *c) {
321   CHECK(REAL(__cxa_throw));
322   __asan_handle_no_return();
323   REAL(__cxa_throw)(a, b, c);
324 }
325 #endif
326 
327 #if ASAN_INTERCEPT___CXA_RETHROW_PRIMARY_EXCEPTION
328 INTERCEPTOR(void, __cxa_rethrow_primary_exception, void *a) {
329   CHECK(REAL(__cxa_rethrow_primary_exception));
330   __asan_handle_no_return();
331   REAL(__cxa_rethrow_primary_exception)(a);
332 }
333 #endif
334 
335 #if ASAN_INTERCEPT__UNWIND_RAISEEXCEPTION
336 INTERCEPTOR(_Unwind_Reason_Code, _Unwind_RaiseException,
337             _Unwind_Exception *object) {
338   CHECK(REAL(_Unwind_RaiseException));
339   __asan_handle_no_return();
340   return REAL(_Unwind_RaiseException)(object);
341 }
342 #endif
343 
344 #if ASAN_INTERCEPT__SJLJ_UNWIND_RAISEEXCEPTION
345 INTERCEPTOR(_Unwind_Reason_Code, _Unwind_SjLj_RaiseException,
346             _Unwind_Exception *object) {
347   CHECK(REAL(_Unwind_SjLj_RaiseException));
348   __asan_handle_no_return();
349   return REAL(_Unwind_SjLj_RaiseException)(object);
350 }
351 #endif
352 
353 #if ASAN_INTERCEPT_INDEX
354 # if ASAN_USE_ALIAS_ATTRIBUTE_FOR_INDEX
355 INTERCEPTOR(char*, index, const char *string, int c)
356   ALIAS(WRAPPER_NAME(strchr));
357 # else
358 #  if SANITIZER_MAC
359 DECLARE_REAL(char*, index, const char *string, int c)
360 OVERRIDE_FUNCTION(index, strchr);
361 #  else
362 DEFINE_REAL(char*, index, const char *string, int c)
363 #  endif
364 # endif
365 #endif  // ASAN_INTERCEPT_INDEX
366 
367 // For both strcat() and strncat() we need to check the validity of |to|
368 // argument irrespective of the |from| length.
369   INTERCEPTOR(char *, strcat, char *to, const char *from) {
370     void *ctx;
371     ASAN_INTERCEPTOR_ENTER(ctx, strcat);
372     ENSURE_ASAN_INITED();
373     if (flags()->replace_str) {
374       uptr from_length = internal_strlen(from);
375       ASAN_READ_RANGE(ctx, from, from_length + 1);
376       uptr to_length = internal_strlen(to);
377       ASAN_READ_STRING_OF_LEN(ctx, to, to_length, to_length);
378       ASAN_WRITE_RANGE(ctx, to + to_length, from_length + 1);
379       // If the copying actually happens, the |from| string should not overlap
380       // with the resulting string starting at |to|, which has a length of
381       // to_length + from_length + 1.
382       if (from_length > 0) {
383         CHECK_RANGES_OVERLAP("strcat", to, from_length + to_length + 1, from,
384                              from_length + 1);
385       }
386     }
387     return REAL(strcat)(to, from);
388   }
389 
390 INTERCEPTOR(char*, strncat, char *to, const char *from, uptr size) {
391   void *ctx;
392   ASAN_INTERCEPTOR_ENTER(ctx, strncat);
393   ENSURE_ASAN_INITED();
394   if (flags()->replace_str) {
395     uptr from_length = MaybeRealStrnlen(from, size);
396     uptr copy_length = Min(size, from_length + 1);
397     ASAN_READ_RANGE(ctx, from, copy_length);
398     uptr to_length = internal_strlen(to);
399     ASAN_READ_STRING_OF_LEN(ctx, to, to_length, to_length);
400     ASAN_WRITE_RANGE(ctx, to + to_length, from_length + 1);
401     if (from_length > 0) {
402       CHECK_RANGES_OVERLAP("strncat", to, to_length + copy_length + 1,
403                            from, copy_length);
404     }
405   }
406   return REAL(strncat)(to, from, size);
407 }
408 
409 INTERCEPTOR(char *, strcpy, char *to, const char *from) {
410   void *ctx;
411   ASAN_INTERCEPTOR_ENTER(ctx, strcpy);
412 #if SANITIZER_MAC
413   if (UNLIKELY(!asan_inited))
414     return REAL(strcpy)(to, from);
415 #endif
416   // strcpy is called from malloc_default_purgeable_zone()
417   // in __asan::ReplaceSystemAlloc() on Mac.
418   if (asan_init_is_running) {
419     return REAL(strcpy)(to, from);
420   }
421   ENSURE_ASAN_INITED();
422   if (flags()->replace_str) {
423     uptr from_size = internal_strlen(from) + 1;
424     CHECK_RANGES_OVERLAP("strcpy", to, from_size, from, from_size);
425     ASAN_READ_RANGE(ctx, from, from_size);
426     ASAN_WRITE_RANGE(ctx, to, from_size);
427   }
428   return REAL(strcpy)(to, from);
429 }
430 
431 INTERCEPTOR(char*, strdup, const char *s) {
432   void *ctx;
433   ASAN_INTERCEPTOR_ENTER(ctx, strdup);
434   if (UNLIKELY(!asan_inited)) return internal_strdup(s);
435   ENSURE_ASAN_INITED();
436   uptr length = internal_strlen(s);
437   if (flags()->replace_str) {
438     ASAN_READ_RANGE(ctx, s, length + 1);
439   }
440   GET_STACK_TRACE_MALLOC;
441   void *new_mem = asan_malloc(length + 1, &stack);
442   REAL(memcpy)(new_mem, s, length + 1);
443   return reinterpret_cast<char*>(new_mem);
444 }
445 
446 #if ASAN_INTERCEPT___STRDUP
447 INTERCEPTOR(char*, __strdup, const char *s) {
448   void *ctx;
449   ASAN_INTERCEPTOR_ENTER(ctx, strdup);
450   if (UNLIKELY(!asan_inited)) return internal_strdup(s);
451   ENSURE_ASAN_INITED();
452   uptr length = internal_strlen(s);
453   if (flags()->replace_str) {
454     ASAN_READ_RANGE(ctx, s, length + 1);
455   }
456   GET_STACK_TRACE_MALLOC;
457   void *new_mem = asan_malloc(length + 1, &stack);
458   REAL(memcpy)(new_mem, s, length + 1);
459   return reinterpret_cast<char*>(new_mem);
460 }
461 #endif // ASAN_INTERCEPT___STRDUP
462 
463 INTERCEPTOR(char*, strncpy, char *to, const char *from, uptr size) {
464   void *ctx;
465   ASAN_INTERCEPTOR_ENTER(ctx, strncpy);
466   ENSURE_ASAN_INITED();
467   if (flags()->replace_str) {
468     uptr from_size = Min(size, MaybeRealStrnlen(from, size) + 1);
469     CHECK_RANGES_OVERLAP("strncpy", to, from_size, from, from_size);
470     ASAN_READ_RANGE(ctx, from, from_size);
471     ASAN_WRITE_RANGE(ctx, to, size);
472   }
473   return REAL(strncpy)(to, from, size);
474 }
475 
476 INTERCEPTOR(long, strtol, const char *nptr, char **endptr, int base) {
477   void *ctx;
478   ASAN_INTERCEPTOR_ENTER(ctx, strtol);
479   ENSURE_ASAN_INITED();
480   if (!flags()->replace_str) {
481     return REAL(strtol)(nptr, endptr, base);
482   }
483   char *real_endptr;
484   long result = REAL(strtol)(nptr, &real_endptr, base);
485   StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
486   return result;
487 }
488 
489 INTERCEPTOR(int, atoi, const char *nptr) {
490   void *ctx;
491   ASAN_INTERCEPTOR_ENTER(ctx, atoi);
492 #if SANITIZER_MAC
493   if (UNLIKELY(!asan_inited)) return REAL(atoi)(nptr);
494 #endif
495   ENSURE_ASAN_INITED();
496   if (!flags()->replace_str) {
497     return REAL(atoi)(nptr);
498   }
499   char *real_endptr;
500   // "man atoi" tells that behavior of atoi(nptr) is the same as
501   // strtol(nptr, 0, 10), i.e. it sets errno to ERANGE if the
502   // parsed integer can't be stored in *long* type (even if it's
503   // different from int). So, we just imitate this behavior.
504   int result = REAL(strtol)(nptr, &real_endptr, 10);
505   FixRealStrtolEndptr(nptr, &real_endptr);
506   ASAN_READ_STRING(ctx, nptr, (real_endptr - nptr) + 1);
507   return result;
508 }
509 
510 INTERCEPTOR(long, atol, const char *nptr) {
511   void *ctx;
512   ASAN_INTERCEPTOR_ENTER(ctx, atol);
513 #if SANITIZER_MAC
514   if (UNLIKELY(!asan_inited)) return REAL(atol)(nptr);
515 #endif
516   ENSURE_ASAN_INITED();
517   if (!flags()->replace_str) {
518     return REAL(atol)(nptr);
519   }
520   char *real_endptr;
521   long result = REAL(strtol)(nptr, &real_endptr, 10);
522   FixRealStrtolEndptr(nptr, &real_endptr);
523   ASAN_READ_STRING(ctx, nptr, (real_endptr - nptr) + 1);
524   return result;
525 }
526 
527 #if ASAN_INTERCEPT_ATOLL_AND_STRTOLL
528 INTERCEPTOR(long long, strtoll, const char *nptr, char **endptr, int base) {
529   void *ctx;
530   ASAN_INTERCEPTOR_ENTER(ctx, strtoll);
531   ENSURE_ASAN_INITED();
532   if (!flags()->replace_str) {
533     return REAL(strtoll)(nptr, endptr, base);
534   }
535   char *real_endptr;
536   long long result = REAL(strtoll)(nptr, &real_endptr, base);
537   StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
538   return result;
539 }
540 
541 INTERCEPTOR(long long, atoll, const char *nptr) {
542   void *ctx;
543   ASAN_INTERCEPTOR_ENTER(ctx, atoll);
544   ENSURE_ASAN_INITED();
545   if (!flags()->replace_str) {
546     return REAL(atoll)(nptr);
547   }
548   char *real_endptr;
549   long long result = REAL(strtoll)(nptr, &real_endptr, 10);
550   FixRealStrtolEndptr(nptr, &real_endptr);
551   ASAN_READ_STRING(ctx, nptr, (real_endptr - nptr) + 1);
552   return result;
553 }
554 #endif  // ASAN_INTERCEPT_ATOLL_AND_STRTOLL
555 
556 #if ASAN_INTERCEPT___CXA_ATEXIT || ASAN_INTERCEPT_ATEXIT
557 static void AtCxaAtexit(void *unused) {
558   (void)unused;
559   StopInitOrderChecking();
560 }
561 #endif
562 
563 #if ASAN_INTERCEPT___CXA_ATEXIT
564 INTERCEPTOR(int, __cxa_atexit, void (*func)(void *), void *arg,
565             void *dso_handle) {
566 #if SANITIZER_MAC
567   if (UNLIKELY(!asan_inited)) return REAL(__cxa_atexit)(func, arg, dso_handle);
568 #endif
569   ENSURE_ASAN_INITED();
570 #if CAN_SANITIZE_LEAKS
571   __lsan::ScopedInterceptorDisabler disabler;
572 #endif
573   int res = REAL(__cxa_atexit)(func, arg, dso_handle);
574   REAL(__cxa_atexit)(AtCxaAtexit, nullptr, nullptr);
575   return res;
576 }
577 #endif  // ASAN_INTERCEPT___CXA_ATEXIT
578 
579 #if ASAN_INTERCEPT_ATEXIT
580 INTERCEPTOR(int, atexit, void (*func)()) {
581   ENSURE_ASAN_INITED();
582 #if CAN_SANITIZE_LEAKS
583   __lsan::ScopedInterceptorDisabler disabler;
584 #endif
585   // Avoid calling real atexit as it is unreachable on at least on Linux.
586   int res = REAL(__cxa_atexit)((void (*)(void *a))func, nullptr, nullptr);
587   REAL(__cxa_atexit)(AtCxaAtexit, nullptr, nullptr);
588   return res;
589 }
590 #endif
591 
592 #if ASAN_INTERCEPT_PTHREAD_ATFORK
593 extern "C" {
594 extern int _pthread_atfork(void (*prepare)(), void (*parent)(),
595                            void (*child)());
596 };
597 
598 INTERCEPTOR(int, pthread_atfork, void (*prepare)(), void (*parent)(),
599             void (*child)()) {
600 #if CAN_SANITIZE_LEAKS
601   __lsan::ScopedInterceptorDisabler disabler;
602 #endif
603   // REAL(pthread_atfork) cannot be called due to symbol indirections at least
604   // on NetBSD
605   return _pthread_atfork(prepare, parent, child);
606 }
607 #endif
608 
609 #if ASAN_INTERCEPT_VFORK
610 DEFINE_REAL(int, vfork)
611 DECLARE_EXTERN_INTERCEPTOR_AND_WRAPPER(int, vfork)
612 #endif
613 
614 // ---------------------- InitializeAsanInterceptors ---------------- {{{1
615 namespace __asan {
616 void InitializeAsanInterceptors() {
617   static bool was_called_once;
618   CHECK(!was_called_once);
619   was_called_once = true;
620   InitializeCommonInterceptors();
621   InitializeSignalInterceptors();
622 
623   // Intercept str* functions.
624   ASAN_INTERCEPT_FUNC(strcat);
625   ASAN_INTERCEPT_FUNC(strcpy);
626   ASAN_INTERCEPT_FUNC(strncat);
627   ASAN_INTERCEPT_FUNC(strncpy);
628   ASAN_INTERCEPT_FUNC(strdup);
629 #if ASAN_INTERCEPT___STRDUP
630   ASAN_INTERCEPT_FUNC(__strdup);
631 #endif
632 #if ASAN_INTERCEPT_INDEX && ASAN_USE_ALIAS_ATTRIBUTE_FOR_INDEX
633   ASAN_INTERCEPT_FUNC(index);
634 #endif
635 
636   ASAN_INTERCEPT_FUNC(atoi);
637   ASAN_INTERCEPT_FUNC(atol);
638   ASAN_INTERCEPT_FUNC(strtol);
639 #if ASAN_INTERCEPT_ATOLL_AND_STRTOLL
640   ASAN_INTERCEPT_FUNC(atoll);
641   ASAN_INTERCEPT_FUNC(strtoll);
642 #endif
643 
644   // Intecept jump-related functions.
645   ASAN_INTERCEPT_FUNC(longjmp);
646 
647 #if ASAN_INTERCEPT_SWAPCONTEXT
648   ASAN_INTERCEPT_FUNC(swapcontext);
649 #endif
650 #if ASAN_INTERCEPT__LONGJMP
651   ASAN_INTERCEPT_FUNC(_longjmp);
652 #endif
653 #if ASAN_INTERCEPT___LONGJMP_CHK
654   ASAN_INTERCEPT_FUNC(__longjmp_chk);
655 #endif
656 #if ASAN_INTERCEPT_SIGLONGJMP
657   ASAN_INTERCEPT_FUNC(siglongjmp);
658 #endif
659 
660   // Intercept exception handling functions.
661 #if ASAN_INTERCEPT___CXA_THROW
662   ASAN_INTERCEPT_FUNC(__cxa_throw);
663 #endif
664 #if ASAN_INTERCEPT___CXA_RETHROW_PRIMARY_EXCEPTION
665   ASAN_INTERCEPT_FUNC(__cxa_rethrow_primary_exception);
666 #endif
667   // Indirectly intercept std::rethrow_exception.
668 #if ASAN_INTERCEPT__UNWIND_RAISEEXCEPTION
669   INTERCEPT_FUNCTION(_Unwind_RaiseException);
670 #endif
671   // Indirectly intercept std::rethrow_exception.
672 #if ASAN_INTERCEPT__UNWIND_SJLJ_RAISEEXCEPTION
673   INTERCEPT_FUNCTION(_Unwind_SjLj_RaiseException);
674 #endif
675 
676   // Intercept threading-related functions
677 #if ASAN_INTERCEPT_PTHREAD_CREATE
678 // TODO: this should probably have an unversioned fallback for newer arches?
679 #if defined(ASAN_PTHREAD_CREATE_VERSION)
680   ASAN_INTERCEPT_FUNC_VER(pthread_create, ASAN_PTHREAD_CREATE_VERSION);
681 #else
682   ASAN_INTERCEPT_FUNC(pthread_create);
683 #endif
684   ASAN_INTERCEPT_FUNC(pthread_join);
685 #endif
686 
687   // Intercept atexit function.
688 #if ASAN_INTERCEPT___CXA_ATEXIT
689   ASAN_INTERCEPT_FUNC(__cxa_atexit);
690 #endif
691 
692 #if ASAN_INTERCEPT_ATEXIT
693   ASAN_INTERCEPT_FUNC(atexit);
694 #endif
695 
696 #if ASAN_INTERCEPT_PTHREAD_ATFORK
697   ASAN_INTERCEPT_FUNC(pthread_atfork);
698 #endif
699 
700 #if ASAN_INTERCEPT_VFORK
701   ASAN_INTERCEPT_FUNC(vfork);
702 #endif
703 
704   InitializePlatformInterceptors();
705 
706   VReport(1, "AddressSanitizer: libc interceptors initialized\n");
707 }
708 
709 } // namespace __asan
710 
711 #endif  // !SANITIZER_FUCHSIA
712