compiler-rt/lib/hwasan/hwasan_allocator.h

   1 //===-- hwasan_allocator.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_ALLOCATOR_H
  14 #define HWASAN_ALLOCATOR_H
  15
  16 #include "hwasan.h"
  17 #include "hwasan_interface_internal.h"
  18 #include "hwasan_mapping.h"
  19 #include "hwasan_poisoning.h"
  20 #include "lsan/lsan_common.h"
  21 #include "sanitizer_common/sanitizer_allocator.h"
  22 #include "sanitizer_common/sanitizer_allocator_checks.h"
  23 #include "sanitizer_common/sanitizer_allocator_interface.h"
  24 #include "sanitizer_common/sanitizer_allocator_report.h"
  25 #include "sanitizer_common/sanitizer_common.h"
  26 #include "sanitizer_common/sanitizer_ring_buffer.h"
  27
  28 #if !defined(__aarch64__) && !defined(__x86_64__) && !(SANITIZER_RISCV64)
  29 #  error Unsupported platform
  30 #endif
  31
  32 namespace __hwasan {
  33
  34 struct Metadata {
  35  private:
  36   atomic_uint64_t alloc_context_id;
  37   u32 requested_size_low;
  38   u16 requested_size_high;
  39   atomic_uint8_t chunk_state;
  40   u8 lsan_tag;
  41
  42  public:
  43   inline void SetAllocated(u32 stack, u64 size);
  44   inline void SetUnallocated();
  45
  46   inline bool IsAllocated() const;
  47   inline u64 GetRequestedSize() const;
  48   inline u32 GetAllocStackId() const;
  49   inline void SetLsanTag(__lsan::ChunkTag tag);
  50   inline __lsan::ChunkTag GetLsanTag() const;
  51 };
  52 static_assert(sizeof(Metadata) == 16);
  53
  54 struct HwasanMapUnmapCallback {
  55   void OnMap(uptr p, uptr size) const { UpdateMemoryUsage(); }
  56   void OnUnmap(uptr p, uptr size) const {
  57     // We are about to unmap a chunk of user memory.
  58     // It can return as user-requested mmap() or another thread stack.
  59     // Make it accessible with zero-tagged pointer.
  60     TagMemory(p, size, 0);
  61   }
  62 };
  63
  64 static const uptr kMaxAllowedMallocSize = 1UL << 40;  // 1T
  65
  66 struct AP64 {
  67   static const uptr kSpaceBeg = ~0ULL;
  68
  69 #if defined(HWASAN_ALIASING_MODE)
  70   static const uptr kSpaceSize = 1ULL << kAddressTagShift;
  71 #else
  72   static const uptr kSpaceSize = 0x2000000000ULL;
  73 #endif
  74   static const uptr kMetadataSize = sizeof(Metadata);
  75   typedef __sanitizer::VeryDenseSizeClassMap SizeClassMap;
  76   using AddressSpaceView = LocalAddressSpaceView;
  77   typedef HwasanMapUnmapCallback MapUnmapCallback;
  78   static const uptr kFlags = 0;
  79 };
  80 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
  81 typedef CombinedAllocator<PrimaryAllocator> Allocator;
  82 typedef Allocator::AllocatorCache AllocatorCache;
  83
  84 void AllocatorSwallowThreadLocalCache(AllocatorCache *cache);
  85
  86 class HwasanChunkView {
  87  public:
  88   HwasanChunkView() : block_(0), metadata_(nullptr) {}
  89   HwasanChunkView(uptr block, Metadata *metadata)
  90       : block_(block), metadata_(metadata) {}
  91   bool IsAllocated() const;    // Checks if the memory is currently allocated
  92   uptr Beg() const;            // First byte of user memory
  93   uptr End() const;            // Last byte of user memory
  94   uptr UsedSize() const;       // Size requested by the user
  95   uptr ActualSize() const;     // Size allocated by the allocator.
  96   u32 GetAllocStackId() const;
  97   bool FromSmallHeap() const;
  98   bool AddrIsInside(uptr addr) const;
  99
 100  private:
 101   friend class __lsan::LsanMetadata;
 102   uptr block_;
 103   Metadata *const metadata_;
 104 };
 105
 106 HwasanChunkView FindHeapChunkByAddress(uptr address);
 107
 108 // Information about one (de)allocation that happened in the past.
 109 // These are recorded in a thread-local ring buffer.
 110 // TODO: this is currently 24 bytes (20 bytes + alignment).
 111 // Compress it to 16 bytes or extend it to be more useful.
 112 struct HeapAllocationRecord {
 113   uptr tagged_addr;
 114   u32  alloc_context_id;
 115   u32  free_context_id;
 116   u32  requested_size;
 117 };
 118
 119 typedef RingBuffer<HeapAllocationRecord> HeapAllocationsRingBuffer;
 120
 121 void GetAllocatorStats(AllocatorStatCounters s);
 122
 123 inline bool InTaggableRegion(uptr addr) {
 124 #if defined(HWASAN_ALIASING_MODE)
 125   // Aliases are mapped next to shadow so that the upper bits match the shadow
 126   // base.
 127   return (addr >> kTaggableRegionCheckShift) ==
 128          (GetShadowOffset() >> kTaggableRegionCheckShift);
 129 #endif
 130   return true;
 131 }
 132
 133 } // namespace __hwasan
 134
 135 #endif // HWASAN_ALLOCATOR_H