asan_malloc_linux.cc revision 83cb7877f608eb9b3d65981095216842f686c527
1//===-- asan_malloc_linux.cc ----------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file is a part of AddressSanitizer, an address sanity checker. 11// 12// Linux-specific malloc interception. 13// We simply define functions like malloc, free, realloc, etc. 14// They will replace the corresponding libc functions automagically. 15//===----------------------------------------------------------------------===// 16#ifdef __linux__ 17 18#include "asan_allocator.h" 19#include "asan_interceptors.h" 20#include "asan_internal.h" 21#include "asan_stack.h" 22#include "asan_thread_registry.h" 23 24#if SANITIZER_ANDROID 25DECLARE_REAL_AND_INTERCEPTOR(void*, malloc, uptr size) 26DECLARE_REAL_AND_INTERCEPTOR(void, free, void *ptr) 27DECLARE_REAL_AND_INTERCEPTOR(void*, calloc, uptr nmemb, uptr size) 28DECLARE_REAL_AND_INTERCEPTOR(void*, realloc, void *ptr, uptr size) 29DECLARE_REAL_AND_INTERCEPTOR(void*, memalign, uptr boundary, uptr size) 30 31struct MallocDebug { 32 void* (*malloc)(uptr bytes); 33 void (*free)(void* mem); 34 void* (*calloc)(uptr n_elements, uptr elem_size); 35 void* (*realloc)(void* oldMem, uptr bytes); 36 void* (*memalign)(uptr alignment, uptr bytes); 37}; 38 39const MallocDebug asan_malloc_dispatch ALIGNED(32) = { 40 WRAP(malloc), WRAP(free), WRAP(calloc), WRAP(realloc), WRAP(memalign) 41}; 42 43extern "C" const MallocDebug* __libc_malloc_dispatch; 44 45namespace __asan { 46void ReplaceSystemMalloc() { 47 __libc_malloc_dispatch = &asan_malloc_dispatch; 48} 49} // namespace __asan 50 51#else // ANDROID 52 53namespace __asan { 54void ReplaceSystemMalloc() { 55} 56} // namespace __asan 57#endif // ANDROID 58 59// ---------------------- Replacement functions ---------------- {{{1 60using namespace __asan; // NOLINT 61 62INTERCEPTOR(void, free, void *ptr) { 63 GET_STACK_TRACE_FREE; 64 asan_free(ptr, &stack, FROM_MALLOC); 65} 66 67INTERCEPTOR(void, cfree, void *ptr) { 68 GET_STACK_TRACE_FREE; 69 asan_free(ptr, &stack, FROM_MALLOC); 70} 71 72INTERCEPTOR(void*, malloc, uptr size) { 73 GET_STACK_TRACE_MALLOC; 74 return asan_malloc(size, &stack); 75} 76 77INTERCEPTOR(void*, calloc, uptr nmemb, uptr size) { 78 if (!asan_inited) { 79 // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym. 80 const uptr kCallocPoolSize = 1024; 81 static uptr calloc_memory_for_dlsym[kCallocPoolSize]; 82 static uptr allocated; 83 uptr size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize; 84 void *mem = (void*)&calloc_memory_for_dlsym[allocated]; 85 allocated += size_in_words; 86 CHECK(allocated < kCallocPoolSize); 87 return mem; 88 } 89 GET_STACK_TRACE_MALLOC; 90 return asan_calloc(nmemb, size, &stack); 91} 92 93INTERCEPTOR(void*, realloc, void *ptr, uptr size) { 94 GET_STACK_TRACE_MALLOC; 95 return asan_realloc(ptr, size, &stack); 96} 97 98INTERCEPTOR(void*, memalign, uptr boundary, uptr size) { 99 GET_STACK_TRACE_MALLOC; 100 return asan_memalign(boundary, size, &stack, FROM_MALLOC); 101} 102 103INTERCEPTOR(void*, __libc_memalign, uptr align, uptr s) 104 ALIAS("memalign"); 105 106INTERCEPTOR(uptr, malloc_usable_size, void *ptr) { 107 GET_STACK_TRACE_MALLOC; 108 return asan_malloc_usable_size(ptr, &stack); 109} 110 111// We avoid including malloc.h for portability reasons. 112// man mallinfo says the fields are "long", but the implementation uses int. 113// It doesn't matter much -- we just need to make sure that the libc's mallinfo 114// is not called. 115struct fake_mallinfo { 116 int x[10]; 117}; 118 119INTERCEPTOR(struct fake_mallinfo, mallinfo, void) { 120 struct fake_mallinfo res; 121 REAL(memset)(&res, 0, sizeof(res)); 122 return res; 123} 124 125INTERCEPTOR(int, mallopt, int cmd, int value) { 126 return -1; 127} 128 129INTERCEPTOR(int, posix_memalign, void **memptr, uptr alignment, uptr size) { 130 GET_STACK_TRACE_MALLOC; 131 // Printf("posix_memalign: %zx %zu\n", alignment, size); 132 return asan_posix_memalign(memptr, alignment, size, &stack); 133} 134 135INTERCEPTOR(void*, valloc, uptr size) { 136 GET_STACK_TRACE_MALLOC; 137 return asan_valloc(size, &stack); 138} 139 140INTERCEPTOR(void*, pvalloc, uptr size) { 141 GET_STACK_TRACE_MALLOC; 142 return asan_pvalloc(size, &stack); 143} 144 145INTERCEPTOR(void, malloc_stats, void) { 146 __asan_print_accumulated_stats(); 147} 148 149#endif // __linux__ 150