libsanitizer/asan/asan_stack.cpp

   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"