libsanitizer/asan/asan_malloc_linux.cc

   1 //===-- asan_malloc_linux.cc ----------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of AddressSanitizer, an address sanity checker.
   9 //
  10 // Linux-specific malloc interception.
  11 // We simply define functions like malloc, free, realloc, etc.
  12 // They will replace the corresponding libc functions automagically.
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "sanitizer_common/sanitizer_platform.h"
  16 #if SANITIZER_LINUX
  17
  18 #include "asan_allocator.h"
  19 #include "asan_interceptors.h"
  20 #include "asan_internal.h"
  21 #include "asan_stack.h"
  22
  23 #if SANITIZER_ANDROID
  24 DECLARE_REAL_AND_INTERCEPTOR(void*, malloc, uptr size)
  25 DECLARE_REAL_AND_INTERCEPTOR(void, free, void *ptr)
  26 DECLARE_REAL_AND_INTERCEPTOR(void*, calloc, uptr nmemb, uptr size)
  27 DECLARE_REAL_AND_INTERCEPTOR(void*, realloc, void *ptr, uptr size)
  28 DECLARE_REAL_AND_INTERCEPTOR(void*, memalign, uptr boundary, uptr size)
  29
  30 struct MallocDebug {
  31   void* (*malloc)(uptr bytes);
  32   void  (*free)(void* mem);
  33   void* (*calloc)(uptr n_elements, uptr elem_size);
  34   void* (*realloc)(void* oldMem, uptr bytes);
  35   void* (*memalign)(uptr alignment, uptr bytes);
  36 };
  37
  38 const MallocDebug asan_malloc_dispatch ALIGNED(32) = {
  39   WRAP(malloc), WRAP(free), WRAP(calloc), WRAP(realloc), WRAP(memalign)
  40 };
  41
  42 extern "C" const MallocDebug* __libc_malloc_dispatch;
  43
  44 namespace __asan {
  45 void ReplaceSystemMalloc() {
  46   __libc_malloc_dispatch = &asan_malloc_dispatch;
  47 }
  48 }  // namespace __asan
  49
  50 #else  // ANDROID
  51
  52 namespace __asan {
  53 void ReplaceSystemMalloc() {
  54 }
  55 }  // namespace __asan
  56 #endif  // ANDROID
  57
  58 // ---------------------- Replacement functions ---------------- {{{1
  59 using namespace __asan;  // NOLINT
  60
  61 INTERCEPTOR(void, free, void *ptr) {
  62   GET_STACK_TRACE_FREE;
  63   asan_free(ptr, &stack, FROM_MALLOC);
  64 }
  65
  66 INTERCEPTOR(void, cfree, void *ptr) {
  67   GET_STACK_TRACE_FREE;
  68   asan_free(ptr, &stack, FROM_MALLOC);
  69 }
  70
  71 INTERCEPTOR(void*, malloc, uptr size) {
  72   GET_STACK_TRACE_MALLOC;
  73   return asan_malloc(size, &stack);
  74 }
  75
  76 INTERCEPTOR(void*, calloc, uptr nmemb, uptr size) {
  77   if (!asan_inited) {
  78     // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym.
  79     const uptr kCallocPoolSize = 1024;
  80     static uptr calloc_memory_for_dlsym[kCallocPoolSize];
  81     static uptr allocated;
  82     uptr size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize;
  83     void *mem = (void*)&calloc_memory_for_dlsym[allocated];
  84     allocated += size_in_words;
  85     CHECK(allocated < kCallocPoolSize);
  86     return mem;
  87   }
  88   GET_STACK_TRACE_MALLOC;
  89   return asan_calloc(nmemb, size, &stack);
  90 }
  91
  92 INTERCEPTOR(void*, realloc, void *ptr, uptr size) {
  93   GET_STACK_TRACE_MALLOC;
  94   return asan_realloc(ptr, size, &stack);
  95 }
  96
  97 INTERCEPTOR(void*, memalign, uptr boundary, uptr size) {
  98   GET_STACK_TRACE_MALLOC;
  99   return asan_memalign(boundary, size, &stack, FROM_MALLOC);
 100 }
 101
 102 INTERCEPTOR(void*, __libc_memalign, uptr align, uptr s)
 103   ALIAS("memalign");
 104
 105 INTERCEPTOR(uptr, malloc_usable_size, void *ptr) {
 106   GET_STACK_TRACE_MALLOC;
 107   return asan_malloc_usable_size(ptr, &stack);
 108 }
 109
 110 // We avoid including malloc.h for portability reasons.
 111 // man mallinfo says the fields are "long", but the implementation uses int.
 112 // It doesn't matter much -- we just need to make sure that the libc's mallinfo
 113 // is not called.
 114 struct fake_mallinfo {
 115   int x[10];
 116 };
 117
 118 INTERCEPTOR(struct fake_mallinfo, mallinfo, void) {
 119   struct fake_mallinfo res;
 120   REAL(memset)(&res, 0, sizeof(res));
 121   return res;
 122 }
 123
 124 INTERCEPTOR(int, mallopt, int cmd, int value) {
 125   return -1;
 126 }
 127
 128 INTERCEPTOR(int, posix_memalign, void **memptr, uptr alignment, uptr size) {
 129   GET_STACK_TRACE_MALLOC;
 130   // Printf("posix_memalign: %zx %zu\n", alignment, size);
 131   return asan_posix_memalign(memptr, alignment, size, &stack);
 132 }
 133
 134 INTERCEPTOR(void*, valloc, uptr size) {
 135   GET_STACK_TRACE_MALLOC;
 136   return asan_valloc(size, &stack);
 137 }
 138
 139 INTERCEPTOR(void*, pvalloc, uptr size) {
 140   GET_STACK_TRACE_MALLOC;
 141   return asan_pvalloc(size, &stack);
 142 }
 143
 144 INTERCEPTOR(void, malloc_stats, void) {
 145   __asan_print_accumulated_stats();
 146 }
 147
 148 #endif  // SANITIZER_LINUX