asan_stack.h revision 296417 
1//===-- asan_stack.h --------------------------------------------*- C++ -*-===//
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// ASan-private header for asan_stack.cc.
13//===----------------------------------------------------------------------===//
14
15#ifndef ASAN_STACK_H
16#define ASAN_STACK_H
17
18#include "asan_flags.h"
19#include "asan_thread.h"
20#include "sanitizer_common/sanitizer_flags.h"
21#include "sanitizer_common/sanitizer_stacktrace.h"
22
23namespace __asan {
24
25static const u32 kDefaultMallocContextSize = 30;
26
27void SetMallocContextSize(u32 size);
28u32 GetMallocContextSize();
29
30// Get the stack trace with the given pc and bp.
31// The pc will be in the position 0 of the resulting stack trace.
32// The bp may refer to the current frame or to the caller's frame.
33ALWAYS_INLINE
34void GetStackTraceWithPcBpAndContext(BufferedStackTrace *stack, uptr max_depth,
35                                     uptr pc, uptr bp, void *context,
36                                     bool fast) {
37#if SANITIZER_WINDOWS
38  stack->Unwind(max_depth, pc, bp, context, 0, 0, fast);
39#else
40  AsanThread *t;
41  stack->size = 0;
42  if (LIKELY(asan_inited)) {
43    if ((t = GetCurrentThread()) && !t->isUnwinding()) {
44      // On FreeBSD the slow unwinding that leverages _Unwind_Backtrace()
45      // yields the call stack of the signal's handler and not of the code
46      // that raised the signal (as it does on Linux).
47      if (SANITIZER_FREEBSD && t->isInDeadlySignal()) fast = true;
48      uptr stack_top = t->stack_top();
49      uptr stack_bottom = t->stack_bottom();
50      ScopedUnwinding unwind_scope(t);
51      stack->Unwind(max_depth, pc, bp, context, stack_top, stack_bottom, fast);
52    } else if (!t && !fast) {
53      /* If GetCurrentThread() has failed, try to do slow unwind anyways. */
54      stack->Unwind(max_depth, pc, bp, context, 0, 0, false);
55    }
56  }
57#endif // SANITIZER_WINDOWS
58}
59
60} // namespace __asan
61
62// NOTE: A Rule of thumb is to retrieve stack trace in the interceptors
63// as early as possible (in functions exposed to the user), as we generally
64// don't want stack trace to contain functions from ASan internals.
65
66#define GET_STACK_TRACE(max_size, fast)                                        \
67  BufferedStackTrace stack;                                                    \
68  if (max_size <= 2) {                                                         \
69    stack.size = max_size;                                                     \
70    if (max_size > 0) {                                                        \
71      stack.top_frame_bp = GET_CURRENT_FRAME();                                \
72      stack.trace_buffer[0] = StackTrace::GetCurrentPc();                      \
73      if (max_size > 1)                                                        \
74        stack.trace_buffer[1] = GET_CALLER_PC();                               \
75    }                                                                          \
76  } else {                                                                     \
77    GetStackTraceWithPcBpAndContext(&stack, max_size,                          \
78                                    StackTrace::GetCurrentPc(),                \
79                                    GET_CURRENT_FRAME(), 0, fast);             \
80  }
81
82#define GET_STACK_TRACE_FATAL(pc, bp)                                          \
83  BufferedStackTrace stack;                                                    \
84  GetStackTraceWithPcBpAndContext(&stack, kStackTraceMax, pc, bp, 0,           \
85                                  common_flags()->fast_unwind_on_fatal)
86
87#define GET_STACK_TRACE_SIGNAL(sig)                                            \
88  BufferedStackTrace stack;                                                    \
89  GetStackTraceWithPcBpAndContext(&stack, kStackTraceMax,                      \
90                                  (sig).pc, (sig).bp, (sig).context,           \
91                                  common_flags()->fast_unwind_on_fatal)
92
93#define GET_STACK_TRACE_FATAL_HERE                                \
94  GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_fatal)
95
96#define GET_STACK_TRACE_CHECK_HERE                                \
97  GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_check)
98
99#define GET_STACK_TRACE_THREAD                                    \
100  GET_STACK_TRACE(kStackTraceMax, true)
101
102#define GET_STACK_TRACE_MALLOC                                                 \
103  GET_STACK_TRACE(GetMallocContextSize(), common_flags()->fast_unwind_on_malloc)
104
105#define GET_STACK_TRACE_FREE GET_STACK_TRACE_MALLOC
106
107#define PRINT_CURRENT_STACK()   \
108  {                             \
109    GET_STACK_TRACE_FATAL_HERE; \
110    stack.Print();              \
111  }
112
113#define PRINT_CURRENT_STACK_CHECK() \
114  {                                 \
115    GET_STACK_TRACE_CHECK_HERE;     \
116    stack.Print();                  \
117  }
118
119#endif // ASAN_STACK_H
120