compiler-rt/lib/hwasan/hwasan_thread.h

   1 //===-- hwasan_thread.h -----------------------------------------*- C++ -*-===//
   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 HWAddressSanitizer.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef HWASAN_THREAD_H
  14 #define HWASAN_THREAD_H
  15
  16 #include "hwasan_allocator.h"
  17 #include "sanitizer_common/sanitizer_common.h"
  18 #include "sanitizer_common/sanitizer_ring_buffer.h"
  19
  20 namespace __hwasan {
  21
  22 typedef __sanitizer::CompactRingBuffer<uptr> StackAllocationsRingBuffer;
  23
  24 class Thread {
  25  public:
  26   // These are optional parameters that can be passed to Init.
  27   struct InitState;
  28
  29   void Init(uptr stack_buffer_start, uptr stack_buffer_size,
  30             const InitState *state = nullptr);
  31
  32   void InitStackAndTls(const InitState *state = nullptr);
  33
  34   // Must be called from the thread itself.
  35   void InitStackRingBuffer(uptr stack_buffer_start, uptr stack_buffer_size);
  36
  37   inline void EnsureRandomStateInited() {
  38     if (UNLIKELY(!random_state_inited_))
  39       InitRandomState();
  40   }
  41
  42   void Destroy();
  43
  44   uptr stack_top() { return stack_top_; }
  45   uptr stack_bottom() { return stack_bottom_; }
  46   uptr stack_size() { return stack_top() - stack_bottom(); }
  47   uptr tls_begin() { return tls_begin_; }
  48   uptr tls_end() { return tls_end_; }
  49   DTLS *dtls() { return dtls_; }
  50   bool IsMainThread() { return unique_id_ == 0; }
  51
  52   bool AddrIsInStack(uptr addr) {
  53     return addr >= stack_bottom_ && addr < stack_top_;
  54   }
  55
  56   AllocatorCache *allocator_cache() { return &allocator_cache_; }
  57   HeapAllocationsRingBuffer *heap_allocations() { return heap_allocations_; }
  58   StackAllocationsRingBuffer *stack_allocations() { return stack_allocations_; }
  59
  60   tag_t GenerateRandomTag(uptr num_bits = kTagBits);
  61
  62   void DisableTagging() { tagging_disabled_++; }
  63   void EnableTagging() { tagging_disabled_--; }
  64
  65   u32 unique_id() const { return unique_id_; }
  66   void Announce() {
  67     if (announced_) return;
  68     announced_ = true;
  69     Print("Thread: ");
  70   }
  71
  72   tid_t os_id() const { return os_id_; }
  73   void set_os_id(tid_t os_id) { os_id_ = os_id; }
  74
  75   uptr &vfork_spill() { return vfork_spill_; }
  76
  77  private:
  78   // NOTE: There is no Thread constructor. It is allocated
  79   // via mmap() and *must* be valid in zero-initialized state.
  80   void ClearShadowForThreadStackAndTLS();
  81   void Print(const char *prefix);
  82   void InitRandomState();
  83   uptr vfork_spill_;
  84   uptr stack_top_;
  85   uptr stack_bottom_;
  86   uptr tls_begin_;
  87   uptr tls_end_;
  88   DTLS *dtls_;
  89
  90   u32 random_state_;
  91   u32 random_buffer_;
  92
  93   AllocatorCache allocator_cache_;
  94   HeapAllocationsRingBuffer *heap_allocations_;
  95   StackAllocationsRingBuffer *stack_allocations_;
  96
  97   u32 unique_id_;  // counting from zero.
  98
  99   tid_t os_id_;
 100
 101   u32 tagging_disabled_;  // if non-zero, malloc uses zero tag in this thread.
 102
 103   bool announced_;
 104
 105   bool random_state_inited_;  // Whether InitRandomState() has been called.
 106
 107   friend struct ThreadListHead;
 108 };
 109
 110 Thread *GetCurrentThread();
 111 uptr *GetCurrentThreadLongPtr();
 112
 113 // Used to handle fork().
 114 void EnsureMainThreadIDIsCorrect();
 115
 116 struct ScopedTaggingDisabler {
 117   ScopedTaggingDisabler() { GetCurrentThread()->DisableTagging(); }
 118   ~ScopedTaggingDisabler() { GetCurrentThread()->EnableTagging(); }
 119 };
 120
 121 } // namespace __hwasan
 122
 123 #endif // HWASAN_THREAD_H