1 //===-- asan_stack.cpp ----------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file is a part of AddressSanitizer, an address sanity checker.
10 //
11 // Code for ASan stack trace.
12 //===----------------------------------------------------------------------===//
13 #include "asan_internal.h"
14 #include "asan_stack.h"
15 #include "sanitizer_common/sanitizer_atomic.h"
16
17 namespace __asan {
18
19 static atomic_uint32_t malloc_context_size;
20
SetMallocContextSize(u32 size)21 void SetMallocContextSize(u32 size) {
22 atomic_store(&malloc_context_size, size, memory_order_release);
23 }
24
GetMallocContextSize()25 u32 GetMallocContextSize() {
26 return atomic_load(&malloc_context_size, memory_order_acquire);
27 }
28
29 namespace {
30
31 // ScopedUnwinding is a scope for stacktracing member of a context
32 class ScopedUnwinding {
33 public:
ScopedUnwinding(AsanThread * t)34 explicit ScopedUnwinding(AsanThread *t) : thread(t) {
35 if (thread) {
36 can_unwind = !thread->isUnwinding();
37 thread->setUnwinding(true);
38 }
39 }
~ScopedUnwinding()40 ~ScopedUnwinding() {
41 if (thread)
42 thread->setUnwinding(false);
43 }
44
CanUnwind() const45 bool CanUnwind() const { return can_unwind; }
46
47 private:
48 AsanThread *thread = nullptr;
49 bool can_unwind = true;
50 };
51
52 } // namespace
53
54 } // namespace __asan
55
UnwindImpl(uptr pc,uptr bp,void * context,bool request_fast,u32 max_depth)56 void __sanitizer::BufferedStackTrace::UnwindImpl(
57 uptr pc, uptr bp, void *context, bool request_fast, u32 max_depth) {
58 using namespace __asan;
59 size = 0;
60 if (UNLIKELY(!AsanInited()))
61 return;
62 request_fast = StackTrace::WillUseFastUnwind(request_fast);
63 AsanThread *t = GetCurrentThread();
64 ScopedUnwinding unwind_scope(t);
65 if (!unwind_scope.CanUnwind())
66 return;
67 if (request_fast) {
68 if (t) {
69 Unwind(max_depth, pc, bp, nullptr, t->stack_top(), t->stack_bottom(),
70 true);
71 }
72 return;
73 }
74 if (SANITIZER_MIPS && t &&
75 !IsValidFrame(bp, t->stack_top(), t->stack_bottom()))
76 return;
77 Unwind(max_depth, pc, bp, context, t ? t->stack_top() : 0,
78 t ? t->stack_bottom() : 0, false);
79 }
80
81 // ------------------ Interface -------------- {{{1
82
83 extern "C" {
84 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_print_stack_trace()85 void __sanitizer_print_stack_trace() {
86 using namespace __asan;
87 PRINT_CURRENT_STACK();
88 }
89 } // extern "C"
90