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 "sanitizer_common/sanitizer_allocator.h" 17 #include "sanitizer_common/sanitizer_allocator_checks.h" 18 #include "sanitizer_common/sanitizer_allocator_interface.h" 19 #include "sanitizer_common/sanitizer_allocator_report.h" 20 #include "sanitizer_common/sanitizer_common.h" 21 #include "sanitizer_common/sanitizer_ring_buffer.h" 22 #include "hwasan_poisoning.h" 23 24 #if !defined(__aarch64__) && !defined(__x86_64__) 25 #error Unsupported platform 26 #endif 27 28 namespace __hwasan { 29 30 struct Metadata { 31 u32 requested_size : 31; // sizes are < 2G. 32 u32 right_aligned : 1; 33 u32 alloc_context_id; 34 }; 35 36 struct HwasanMapUnmapCallback { 37 void OnMap(uptr p, uptr size) const { UpdateMemoryUsage(); } 38 void OnUnmap(uptr p, uptr size) const { 39 // We are about to unmap a chunk of user memory. 40 // It can return as user-requested mmap() or another thread stack. 41 // Make it accessible with zero-tagged pointer. 42 TagMemory(p, size, 0); 43 } 44 }; 45 46 static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G 47 48 struct AP64 { 49 static const uptr kSpaceBeg = ~0ULL; 50 static const uptr kSpaceSize = 0x2000000000ULL; 51 static const uptr kMetadataSize = sizeof(Metadata); 52 typedef __sanitizer::VeryDenseSizeClassMap SizeClassMap; 53 using AddressSpaceView = LocalAddressSpaceView; 54 typedef HwasanMapUnmapCallback MapUnmapCallback; 55 static const uptr kFlags = 0; 56 }; 57 typedef SizeClassAllocator64<AP64> PrimaryAllocator; 58 typedef CombinedAllocator<PrimaryAllocator> Allocator; 59 typedef Allocator::AllocatorCache AllocatorCache; 60 61 void AllocatorSwallowThreadLocalCache(AllocatorCache *cache); 62 63 class HwasanChunkView { 64 public: 65 HwasanChunkView() : block_(0), metadata_(nullptr) {} 66 HwasanChunkView(uptr block, Metadata *metadata) 67 : block_(block), metadata_(metadata) {} 68 bool IsAllocated() const; // Checks if the memory is currently allocated 69 uptr Beg() const; // First byte of user memory 70 uptr End() const; // Last byte of user memory 71 uptr UsedSize() const; // Size requested by the user 72 uptr ActualSize() const; // Size allocated by the allocator. 73 u32 GetAllocStackId() const; 74 bool FromSmallHeap() const; 75 private: 76 uptr block_; 77 Metadata *const metadata_; 78 }; 79 80 HwasanChunkView FindHeapChunkByAddress(uptr address); 81 82 // Information about one (de)allocation that happened in the past. 83 // These are recorded in a thread-local ring buffer. 84 // TODO: this is currently 24 bytes (20 bytes + alignment). 85 // Compress it to 16 bytes or extend it to be more useful. 86 struct HeapAllocationRecord { 87 uptr tagged_addr; 88 u32 alloc_context_id; 89 u32 free_context_id; 90 u32 requested_size; 91 }; 92 93 typedef RingBuffer<HeapAllocationRecord> HeapAllocationsRingBuffer; 94 95 void GetAllocatorStats(AllocatorStatCounters s); 96 97 } // namespace __hwasan 98 99 #endif // HWASAN_ALLOCATOR_H 100