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MemoryChecking.h (4168B)


      1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
      3 /* This Source Code Form is subject to the terms of the Mozilla Public
      4 * License, v. 2.0. If a copy of the MPL was not distributed with this
      5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      6 
      7 /*
      8 * Provides a common interface to the ASan (AddressSanitizer) and Valgrind
      9 * functions used to mark memory in certain ways. In detail, the following
     10 * three macros are provided:
     11 *
     12 *   MOZ_MAKE_MEM_NOACCESS  - Mark memory as unsafe to access (e.g. freed)
     13 *   MOZ_MAKE_MEM_UNDEFINED - Mark memory as accessible, with content undefined
     14 *   MOZ_MAKE_MEM_DEFINED - Mark memory as accessible, with content defined
     15 *
     16 * With Valgrind in use, these directly map to the three respective Valgrind
     17 * macros. With ASan in use, the NOACCESS macro maps to poisoning the memory,
     18 * while the UNDEFINED/DEFINED macros unpoison memory.
     19 *
     20 * With no memory checker available, all macros expand to the empty statement.
     21 */
     22 
     23 #ifndef mozilla_MemoryChecking_h
     24 #define mozilla_MemoryChecking_h
     25 
     26 #if defined(MOZ_VALGRIND)
     27 #  include "valgrind/memcheck.h"
     28 #endif
     29 
     30 #if defined(MOZ_ASAN) || defined(MOZ_VALGRIND)
     31 #  define MOZ_HAVE_MEM_CHECKS 1
     32 #endif
     33 
     34 #if defined(MOZ_ASAN)
     35 #  include <stddef.h>
     36 
     37 #  include "mozilla/Types.h"
     38 
     39 #  ifdef _MSC_VER
     40 // In clang-cl based ASAN, we link against the memory poisoning functions
     41 // statically.
     42 #    define MOZ_ASAN_VISIBILITY
     43 #  else
     44 #    define MOZ_ASAN_VISIBILITY MOZ_EXPORT
     45 #  endif
     46 
     47 extern "C" {
     48 /* These definitions are usually provided through the
     49 * sanitizer/asan_interface.h header installed by ASan.
     50 */
     51 void MOZ_ASAN_VISIBILITY __asan_poison_memory_region(void const volatile* addr,
     52                                                     size_t size);
     53 void MOZ_ASAN_VISIBILITY
     54 __asan_unpoison_memory_region(void const volatile* addr, size_t size);
     55 
     56 #  define MOZ_MAKE_MEM_NOACCESS(addr, size) \
     57    __asan_poison_memory_region((addr), (size))
     58 
     59 #  define MOZ_MAKE_MEM_UNDEFINED(addr, size) \
     60    __asan_unpoison_memory_region((addr), (size))
     61 
     62 #  define MOZ_MAKE_MEM_DEFINED(addr, size) \
     63    __asan_unpoison_memory_region((addr), (size))
     64 
     65 /*
     66 * These definitions are usually provided through the
     67 * sanitizer/lsan_interface.h header installed by LSan.
     68 */
     69 void MOZ_EXPORT __lsan_ignore_object(const void* p);
     70 }
     71 #elif defined(MOZ_MSAN)
     72 #  include <stddef.h>
     73 
     74 #  include "mozilla/Types.h"
     75 
     76 extern "C" {
     77 /* These definitions are usually provided through the
     78 * sanitizer/msan_interface.h header installed by MSan.
     79 */
     80 void MOZ_EXPORT __msan_poison(void const volatile* addr, size_t size);
     81 void MOZ_EXPORT __msan_unpoison(void const volatile* addr, size_t size);
     82 
     83 #  define MOZ_MAKE_MEM_NOACCESS(addr, size) __msan_poison((addr), (size))
     84 
     85 #  define MOZ_MAKE_MEM_UNDEFINED(addr, size) __msan_poison((addr), (size))
     86 
     87 #  define MOZ_MAKE_MEM_DEFINED(addr, size) __msan_unpoison((addr), (size))
     88 }
     89 #elif defined(MOZ_VALGRIND)
     90 #  define MOZ_MAKE_MEM_NOACCESS(addr, size) \
     91    VALGRIND_MAKE_MEM_NOACCESS((addr), (size))
     92 
     93 #  define MOZ_MAKE_MEM_UNDEFINED(addr, size) \
     94    VALGRIND_MAKE_MEM_UNDEFINED((addr), (size))
     95 
     96 #  define MOZ_MAKE_MEM_DEFINED(addr, size) \
     97    VALGRIND_MAKE_MEM_DEFINED((addr), (size))
     98 #else
     99 
    100 #  define MOZ_MAKE_MEM_NOACCESS(addr, size) \
    101    do {                                    \
    102    } while (0)
    103 #  define MOZ_MAKE_MEM_UNDEFINED(addr, size) \
    104    do {                                     \
    105    } while (0)
    106 #  define MOZ_MAKE_MEM_DEFINED(addr, size) \
    107    do {                                   \
    108    } while (0)
    109 
    110 #endif
    111 
    112 /*
    113 * MOZ_LSAN_INTENTIONAL_LEAK(X) is a macro to tell LeakSanitizer that X
    114 * points to a value that will intentionally never be deallocated during
    115 * the execution of the process.
    116 *
    117 * Additional uses of this macro should be reviewed by people
    118 * conversant in leak-checking and/or MFBT peers.
    119 */
    120 #if defined(MOZ_ASAN)
    121 #  define MOZ_LSAN_INTENTIONALLY_LEAK_OBJECT(X) __lsan_ignore_object(X)
    122 #else
    123 #  define MOZ_LSAN_INTENTIONALLY_LEAK_OBJECT(X) /* nothing */
    124 #endif                                          // defined(MOZ_ASAN)
    125 
    126 #endif /* mozilla_MemoryChecking_h */