xref: /freebsd/contrib/llvm-project/compiler-rt/lib/asan/asan_stack.cpp (revision e17f5b1d307b7b8910d67883e57a9604305906d5)
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 
21 void SetMallocContextSize(u32 size) {
22   atomic_store(&malloc_context_size, size, memory_order_release);
23 }
24 
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:
34   explicit ScopedUnwinding(AsanThread *t) : thread(t) {
35     if (thread) {
36       can_unwind = !thread->isUnwinding();
37       thread->setUnwinding(true);
38     }
39   }
40   ~ScopedUnwinding() {
41     if (thread)
42       thread->setUnwinding(false);
43   }
44 
45   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 
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(!asan_inited))
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, 0, 0, false);
78 }
79 
80 // ------------------ Interface -------------- {{{1
81 
82 extern "C" {
83 SANITIZER_INTERFACE_ATTRIBUTE
84 void __sanitizer_print_stack_trace() {
85   using namespace __asan;
86   PRINT_CURRENT_STACK();
87 }
88 }  // extern "C"
89