libsanitizer/asan/asan_interceptors_memintrinsics.cpp

   1 //===-- asan_interceptors_memintrinsics.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 // ASan versions of memcpy, memmove, and memset.
  12 //===---------------------------------------------------------------------===//
  13
  14 #define SANITIZER_COMMON_NO_REDEFINE_BUILTINS
  15
  16 #include "asan_interceptors_memintrinsics.h"
  17
  18 #include "asan_interceptors.h"
  19 #include "asan_report.h"
  20 #include "asan_stack.h"
  21 #include "asan_suppressions.h"
  22
  23 using namespace __asan;
  24
  25 // memcpy is called during __asan_init() from the internals of printf(...).
  26 // We do not treat memcpy with to==from as a bug.
  27 // See http://llvm.org/bugs/show_bug.cgi?id=11763.
  28 #define ASAN_MEMCPY_IMPL(ctx, to, from, size)                 \
  29   do {                                                        \
  30     if (LIKELY(replace_intrin_cached)) {                      \
  31       if (LIKELY(to != from)) {                               \
  32         CHECK_RANGES_OVERLAP("memcpy", to, size, from, size); \
  33       }                                                       \
  34       ASAN_READ_RANGE(ctx, from, size);                       \
  35       ASAN_WRITE_RANGE(ctx, to, size);                        \
  36     } else if (UNLIKELY(!AsanInited())) {                     \
  37       return internal_memcpy(to, from, size);                 \
  38     }                                                         \
  39     return REAL(memcpy)(to, from, size);                      \
  40   } while (0)
  41
  42 // memset is called inside Printf.
  43 #define ASAN_MEMSET_IMPL(ctx, block, c, size) \
  44   do {                                        \
  45     if (LIKELY(replace_intrin_cached)) {      \
  46       ASAN_WRITE_RANGE(ctx, block, size);     \
  47     } else if (UNLIKELY(!AsanInited())) {     \
  48       return internal_memset(block, c, size); \
  49     }                                         \
  50     return REAL(memset)(block, c, size);      \
  51   } while (0)
  52
  53 #define ASAN_MEMMOVE_IMPL(ctx, to, from, size) \
  54   do {                                         \
  55     if (LIKELY(replace_intrin_cached)) {       \
  56       ASAN_READ_RANGE(ctx, from, size);        \
  57       ASAN_WRITE_RANGE(ctx, to, size);         \
  58     }                                          \
  59     return internal_memmove(to, from, size);   \
  60   } while (0)
  61
  62 void *__asan_memcpy(void *to, const void *from, uptr size) {
  63   ASAN_MEMCPY_IMPL(nullptr, to, from, size);
  64 }
  65
  66 void *__asan_memset(void *block, int c, uptr size) {
  67   ASAN_MEMSET_IMPL(nullptr, block, c, size);
  68 }
  69
  70 void *__asan_memmove(void *to, const void *from, uptr size) {
  71   ASAN_MEMMOVE_IMPL(nullptr, to, from, size);
  72 }
  73
  74 #if SANITIZER_FUCHSIA
  75
  76 // Fuchsia doesn't use sanitizer_common_interceptors.inc, but
  77 // the only things there it wants are these three.  Just define them
  78 // as aliases here rather than repeating the contents.
  79
  80 extern "C" decltype(__asan_memcpy) memcpy[[gnu::alias("__asan_memcpy")]];
  81 extern "C" decltype(__asan_memmove) memmove[[gnu::alias("__asan_memmove")]];
  82 extern "C" decltype(__asan_memset) memset[[gnu::alias("__asan_memset")]];
  83
  84 #else  // SANITIZER_FUCHSIA
  85
  86 #define COMMON_INTERCEPTOR_MEMMOVE_IMPL(ctx, to, from, size) \
  87   do {                                                       \
  88     ASAN_INTERCEPTOR_ENTER(ctx, memmove);                    \
  89     ASAN_MEMMOVE_IMPL(ctx, to, from, size);                  \
  90   } while (false)
  91
  92 #define COMMON_INTERCEPTOR_MEMCPY_IMPL(ctx, to, from, size) \
  93   do {                                                      \
  94     ASAN_INTERCEPTOR_ENTER(ctx, memcpy);                    \
  95     ASAN_MEMCPY_IMPL(ctx, to, from, size);                  \
  96   } while (false)
  97
  98 #define COMMON_INTERCEPTOR_MEMSET_IMPL(ctx, block, c, size) \
  99   do {                                                      \
 100     ASAN_INTERCEPTOR_ENTER(ctx, memset);                    \
 101     ASAN_MEMSET_IMPL(ctx, block, c, size);                  \
 102   } while (false)
 103
 104 #include "sanitizer_common/sanitizer_common_interceptors_memintrinsics.inc"
 105
 106 #endif  // SANITIZER_FUCHSIA