libsanitizer/asan/asan_debugging.cc

   1 //===-- asan_debugging.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 // This file contains various functions that are generally useful to call when
  11 // using a debugger (LLDB, GDB).
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "asan_allocator.h"
  15 #include "asan_flags.h"
  16 #include "asan_internal.h"
  17 #include "asan_mapping.h"
  18 #include "asan_thread.h"
  19
  20 namespace __asan {
  21
  22 uptr AsanGetStack(uptr addr, uptr *trace, uptr size, u32 *thread_id,
  23                   bool alloc_stack) {
  24   AsanChunkView chunk = FindHeapChunkByAddress(addr);
  25   if (!chunk.IsValid()) return 0;
  26
  27   StackTrace stack;
  28   if (alloc_stack) {
  29     if (chunk.AllocTid() == kInvalidTid) return 0;
  30     chunk.GetAllocStack(&stack);
  31     if (thread_id) *thread_id = chunk.AllocTid();
  32   } else {
  33     if (chunk.FreeTid() == kInvalidTid) return 0;
  34     chunk.GetFreeStack(&stack);
  35     if (thread_id) *thread_id = chunk.FreeTid();
  36   }
  37
  38   if (trace && size) {
  39     if (size > kStackTraceMax)
  40       size = kStackTraceMax;
  41     if (size > stack.size)
  42       size = stack.size;
  43     for (uptr i = 0; i < size; i++)
  44       trace[i] = StackTrace::GetPreviousInstructionPc(stack.trace[i]);
  45
  46     return size;
  47   }
  48
  49   return 0;
  50 }
  51
  52 }  // namespace __asan
  53
  54 using namespace __asan;
  55
  56 SANITIZER_INTERFACE_ATTRIBUTE
  57 uptr __asan_get_alloc_stack(uptr addr, uptr *trace, uptr size, u32 *thread_id) {
  58   return AsanGetStack(addr, trace, size, thread_id, /* alloc_stack */ true);
  59 }
  60
  61 SANITIZER_INTERFACE_ATTRIBUTE
  62 uptr __asan_get_free_stack(uptr addr, uptr *trace, uptr size, u32 *thread_id) {
  63   return AsanGetStack(addr, trace, size, thread_id, /* alloc_stack */ false);
  64 }
  65
  66 SANITIZER_INTERFACE_ATTRIBUTE
  67 void __asan_get_shadow_mapping(uptr *shadow_scale, uptr *shadow_offset) {
  68   if (shadow_scale)
  69     *shadow_scale = SHADOW_SCALE;
  70   if (shadow_offset)
  71     *shadow_offset = SHADOW_OFFSET;
  72 }