libcxx/include/__debug_utils/sanitizers.h

   1 //===----------------------------------------------------------------------===//
   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 #ifndef _LIBCPP___LIBCXX_DEBUG_UTILS_SANITIZERS_H
  10 #define _LIBCPP___LIBCXX_DEBUG_UTILS_SANITIZERS_H
  11
  12 #include <__config>
  13 #include <__type_traits/integral_constant.h>
  14 #include <__type_traits/is_constant_evaluated.h>
  15
  16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  17 #  pragma GCC system_header
  18 #endif
  19
  20 #if _LIBCPP_HAS_ASAN
  21
  22 extern "C" {
  23 _LIBCPP_EXPORTED_FROM_ABI void
  24 __sanitizer_annotate_contiguous_container(const void*, const void*, const void*, const void*);
  25 _LIBCPP_EXPORTED_FROM_ABI void __sanitizer_annotate_double_ended_contiguous_container(
  26     const void*, const void*, const void*, const void*, const void*, const void*);
  27 _LIBCPP_EXPORTED_FROM_ABI int
  28 __sanitizer_verify_double_ended_contiguous_container(const void*, const void*, const void*, const void*);
  29 }
  30
  31 #endif // _LIBCPP_HAS_ASAN
  32
  33 _LIBCPP_BEGIN_NAMESPACE_STD
  34
  35 // ASan choices
  36 #if _LIBCPP_HAS_ASAN
  37 #  define _LIBCPP_HAS_ASAN_CONTAINER_ANNOTATIONS_FOR_ALL_ALLOCATORS 1
  38 #endif
  39
  40 #ifdef _LIBCPP_HAS_ASAN_CONTAINER_ANNOTATIONS_FOR_ALL_ALLOCATORS
  41 // __asan_annotate_container_with_allocator determines whether containers with custom allocators are annotated. This is
  42 // a public customization point to disable annotations if the custom allocator assumes that the memory isn't poisoned.
  43 // See the https://libcxx.llvm.org/UsingLibcxx.html#turning-off-asan-annotation-in-containers for more information.
  44 template <class _Alloc>
  45 struct __asan_annotate_container_with_allocator : true_type {};
  46 #endif
  47
  48 // Annotate a double-ended contiguous range.
  49 // - [__first_storage, __last_storage) is the allocated memory region,
  50 // - [__first_old_contained, __last_old_contained) is the previously allowed (unpoisoned) range, and
  51 // - [__first_new_contained, __last_new_contained) is the new allowed (unpoisoned) range.
  52 template <class _Allocator>
  53 _LIBCPP_HIDE_FROM_ABI void __annotate_double_ended_contiguous_container(
  54     const void* __first_storage,
  55     const void* __last_storage,
  56     const void* __first_old_contained,
  57     const void* __last_old_contained,
  58     const void* __first_new_contained,
  59     const void* __last_new_contained) {
  60 #if !_LIBCPP_HAS_ASAN
  61   (void)__first_storage;
  62   (void)__last_storage;
  63   (void)__first_old_contained;
  64   (void)__last_old_contained;
  65   (void)__first_new_contained;
  66   (void)__last_new_contained;
  67 #else
  68   if (__asan_annotate_container_with_allocator<_Allocator>::value && __first_storage != nullptr)
  69     __sanitizer_annotate_double_ended_contiguous_container(
  70         __first_storage,
  71         __last_storage,
  72         __first_old_contained,
  73         __last_old_contained,
  74         __first_new_contained,
  75         __last_new_contained);
  76 #endif
  77 }
  78
  79 // Annotate a contiguous range.
  80 // [__first_storage, __last_storage) is the allocated memory region,
  81 // __old_last_contained is the previously last allowed (unpoisoned) element, and
  82 // __new_last_contained is the new last allowed (unpoisoned) element.
  83 template <class _Allocator>
  84 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __annotate_contiguous_container(
  85     const void* __first_storage,
  86     const void* __last_storage,
  87     const void* __old_last_contained,
  88     const void* __new_last_contained) {
  89 #if !_LIBCPP_HAS_ASAN
  90   (void)__first_storage;
  91   (void)__last_storage;
  92   (void)__old_last_contained;
  93   (void)__new_last_contained;
  94 #else
  95   if (!__libcpp_is_constant_evaluated() && __asan_annotate_container_with_allocator<_Allocator>::value &&
  96       __first_storage != nullptr)
  97     __sanitizer_annotate_contiguous_container(
  98         __first_storage, __last_storage, __old_last_contained, __new_last_contained);
  99 #endif
 100 }
 101
 102 _LIBCPP_END_NAMESPACE_STD
 103
 104 #endif // _LIBCPP___LIBCXX_DEBUG_UTILS_SANITIZERS_H