1//===-- asan_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 AddressSanitizer, an address sanity checker.
10//
11// ASan-private header for asan_allocator.cpp.
12//===----------------------------------------------------------------------===//
13
14#ifndef ASAN_ALLOCATOR_H
15#define ASAN_ALLOCATOR_H
16
17#include "asan_flags.h"
18#include "asan_interceptors.h"
19#include "asan_internal.h"
20#include "sanitizer_common/sanitizer_allocator.h"
21#include "sanitizer_common/sanitizer_list.h"
22#include "sanitizer_common/sanitizer_platform.h"
23
24namespace __asan {
25
26enum AllocType {
27 FROM_MALLOC = 1, // Memory block came from malloc, calloc, realloc, etc.
28 FROM_NEW = 2, // Memory block came from operator new.
29 FROM_NEW_BR = 3 // Memory block came from operator new [ ]
30};
31
32class AsanChunk;
33
34struct AllocatorOptions {
35 u32 quarantine_size_mb;
36 u32 thread_local_quarantine_size_kb;
37 u16 min_redzone;
38 u16 max_redzone;
39 u8 may_return_null;
40 u8 alloc_dealloc_mismatch;
41 s32 release_to_os_interval_ms;
42
43 void SetFrom(const Flags *f, const CommonFlags *cf);
44 void CopyTo(Flags *f, CommonFlags *cf);
45};
46
47void InitializeAllocator(const AllocatorOptions &options);
48void ReInitializeAllocator(const AllocatorOptions &options);
49void GetAllocatorOptions(AllocatorOptions *options);
50void ApplyAllocatorOptions(const AllocatorOptions &options);
51
52class AsanChunkView {
53 public:
54 explicit AsanChunkView(AsanChunk *chunk) : chunk_(chunk) {}
55 bool IsValid() const; // Checks if AsanChunkView points to a valid
56 // allocated or quarantined chunk.
57 bool IsAllocated() const; // Checks if the memory is currently allocated.
58 bool IsQuarantined() const; // Checks if the memory is currently quarantined.
59 uptr Beg() const; // First byte of user memory.
60 uptr End() const; // Last byte of user memory.
61 uptr UsedSize() const; // Size requested by the user.
62 u32 UserRequestedAlignment() const; // Originally requested alignment.
63 uptr AllocTid() const;
64 uptr FreeTid() const;
65 bool Eq(const AsanChunkView &c) const { return chunk_ == c.chunk_; }
66 u32 GetAllocStackId() const;
67 u32 GetFreeStackId() const;
68 AllocType GetAllocType() const;
69 bool AddrIsInside(uptr addr, uptr access_size, sptr *offset) const {
70 if (addr >= Beg() && (addr + access_size) <= End()) {
71 *offset = addr - Beg();
72 return true;
73 }
74 return false;
75 }
76 bool AddrIsAtLeft(uptr addr, uptr access_size, sptr *offset) const {
77 (void)access_size;
78 if (addr < Beg()) {
79 *offset = Beg() - addr;
80 return true;
81 }
82 return false;
83 }
84 bool AddrIsAtRight(uptr addr, uptr access_size, sptr *offset) const {
85 if (addr + access_size > End()) {
86 *offset = addr - End();
87 return true;
88 }
89 return false;
90 }
91
92 private:
93 AsanChunk *const chunk_;
94};
95
96AsanChunkView FindHeapChunkByAddress(uptr address);
97AsanChunkView FindHeapChunkByAllocBeg(uptr address);
98
99// List of AsanChunks with total size.
100class AsanChunkFifoList: public IntrusiveList<AsanChunk> {
101 public:
102 explicit AsanChunkFifoList(LinkerInitialized) { }
103 AsanChunkFifoList() { clear(); }
104 void Push(AsanChunk *n);
105 void PushList(AsanChunkFifoList *q);
106 AsanChunk *Pop();
107 uptr size() { return size_; }
108 void clear() {
109 IntrusiveList<AsanChunk>::clear();
110 size_ = 0;
111 }
112 private:
113 uptr size_;
114};
115
116struct AsanMapUnmapCallback {
117 void OnMap(uptr p, uptr size) const;
118 void OnMapSecondary(uptr p, uptr size, uptr user_begin, uptr user_size) const;
119 void OnUnmap(uptr p, uptr size) const;
120};
121
122#if SANITIZER_CAN_USE_ALLOCATOR64
123# if SANITIZER_FUCHSIA
124// This is a sentinel indicating we do not want the primary allocator arena to
125// be placed at a fixed address. It will be anonymously mmap'd.
126const uptr kAllocatorSpace = ~(uptr)0;
127# if SANITIZER_RISCV64
128
129// These are sanitizer tunings that allow all bringup tests for RISCV-64 Sv39 +
130// Fuchsia to run with asan-instrumented. That is, we can run bringup, e2e,
131// libc, and scudo tests with this configuration.
132//
133// TODO: This is specifically tuned for Sv39. 48/57 will likely require other
134// tunings, or possibly use the same tunings Fuchsia uses for other archs. The
135// VMA size isn't technically tied to the Fuchsia System ABI, so once 48/57 is
136// supported, we'd need a way of dynamically checking what the VMA size is and
137// determining optimal configuration.
138
139// This indicates the total amount of space dedicated for the primary allocator
140// during initialization. This is roughly proportional to the size set by the
141// FuchsiaConfig for scudo (~11.25GB == ~2^33.49). Requesting any more could
142// lead to some failures in sanitized bringup tests where we can't allocate new
143// vmars because there wouldn't be enough contiguous space. We could try 2^34 if
144// we re-evaluate the SizeClassMap settings.
145const uptr kAllocatorSize = UINT64_C(1) << 33; // 8GB
146
147// This is roughly equivalent to the configuration for the VeryDenseSizeClassMap
148// but has fewer size classes (ideally at most 32). Fewer class sizes means the
149// region size for each class is larger, thus less chances of running out of
150// space for each region. The main differences are the MidSizeLog (which is
151// smaller) and the MaxSizeLog (which is larger).
152//
153// - The MaxSizeLog is higher to allow some of the largest allocations I've
154// observed to be placed in the primary allocator's arena as opposed to being
155// mmap'd by the secondary allocator. This helps reduce fragmentation from
156// large classes. A huge example of this the scudo allocator tests (and its
157// testing infrastructure) which malloc's/new's objects on the order of
158// hundreds of kilobytes which normally would not be in the primary allocator
159// arena with the default VeryDenseSizeClassMap.
160// - The MidSizeLog is reduced to help shrink the number of size classes and
161// increase region size. Without this, we'd see ASan complain many times about
162// a region running out of available space.
163//
164// This differs a bit from the fuchsia config in scudo, mainly from the NumBits,
165// MaxSizeLog, and NumCachedHintT. This should place the number of size classes
166// for scudo at 45 and some large objects allocated by this config would be
167// placed in the arena whereas scudo would mmap them. The asan allocator needs
168// to have a number of classes that are a power of 2 for various internal things
169// to work, so we can't match the scudo settings to a tee. The sanitizer
170// allocator is slightly slower than scudo's but this is enough to get
171// memory-intensive scudo tests to run with asan instrumentation.
172typedef SizeClassMap</*kNumBits=*/2,
173 /*kMinSizeLog=*/5,
174 /*kMidSizeLog=*/8,
175 /*kMaxSizeLog=*/18,
176 /*kNumCachedHintT=*/8,
177 /*kMaxBytesCachedLog=*/10>
178 SizeClassMap;
179static_assert(SizeClassMap::kNumClassesRounded <= 32,
180 "The above tunings were specifically selected to ensure there "
181 "would be at most 32 size classes. This restriction could be "
182 "loosened to 64 size classes if we can find a configuration of "
183 "allocator size and SizeClassMap tunings that allows us to "
184 "reliably run all bringup tests in a sanitized environment.");
185
186# else // SANITIZER_RISCV64
187// These are the default allocator tunings for non-RISCV environments where the
188// VMA is usually 48 bits and we have lots of space.
189const uptr kAllocatorSize = 0x40000000000ULL; // 4T.
190typedef DefaultSizeClassMap SizeClassMap;
191# endif // SANITIZER_RISCV64
192# else // SANITIZER_FUCHSIA
193
194# if SANITIZER_APPLE
195const uptr kAllocatorSpace = 0x600000000000ULL;
196# else // SANITIZER_APPLE
197const uptr kAllocatorSpace = ~(uptr)0;
198# endif // SANITIZER_APPLE
199
200# if defined(__powerpc64__)
201const uptr kAllocatorSize = 0x20000000000ULL; // 2T.
202typedef DefaultSizeClassMap SizeClassMap;
203# elif defined(__aarch64__) && SANITIZER_ANDROID
204// Android needs to support 39, 42 and 48 bit VMA.
205const uptr kAllocatorSize = 0x2000000000ULL; // 128G.
206typedef VeryCompactSizeClassMap SizeClassMap;
207# elif SANITIZER_RISCV64
208const uptr kAllocatorSize = 0x2000000000ULL; // 128G.
209typedef VeryDenseSizeClassMap SizeClassMap;
210# elif defined(__sparc__)
211const uptr kAllocatorSize = 0x20000000000ULL; // 2T.
212typedef DefaultSizeClassMap SizeClassMap;
213# elif SANITIZER_WINDOWS
214const uptr kAllocatorSize = 0x8000000000ULL; // 500G
215typedef DefaultSizeClassMap SizeClassMap;
216# elif SANITIZER_APPLE
217const uptr kAllocatorSize = 0x40000000000ULL; // 4T.
218typedef DefaultSizeClassMap SizeClassMap;
219# else
220const uptr kAllocatorSize = 0x40000000000ULL; // 4T.
221typedef DefaultSizeClassMap SizeClassMap;
222# endif // defined(__powerpc64__) etc.
223# endif // SANITIZER_FUCHSIA
224template <typename AddressSpaceViewTy>
225struct AP64 { // Allocator64 parameters. Deliberately using a short name.
226 static const uptr kSpaceBeg = kAllocatorSpace;
227 static const uptr kSpaceSize = kAllocatorSize;
228 static const uptr kMetadataSize = 0;
229 typedef __asan::SizeClassMap SizeClassMap;
230 typedef AsanMapUnmapCallback MapUnmapCallback;
231 static const uptr kFlags = 0;
232 using AddressSpaceView = AddressSpaceViewTy;
233};
234
235template <typename AddressSpaceView>
236using PrimaryAllocatorASVT = SizeClassAllocator64<AP64<AddressSpaceView>>;
237using PrimaryAllocator = PrimaryAllocatorASVT<LocalAddressSpaceView>;
238#else // SANITIZER_CAN_USE_ALLOCATOR64. Fallback to SizeClassAllocator32.
239typedef CompactSizeClassMap SizeClassMap;
240template <typename AddressSpaceViewTy>
241struct AP32 {
242 static const uptr kSpaceBeg = 0;
243 static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
244 static const uptr kMetadataSize = 0;
245 typedef __asan::SizeClassMap SizeClassMap;
246 static const uptr kRegionSizeLog = 20;
247 using AddressSpaceView = AddressSpaceViewTy;
248 typedef AsanMapUnmapCallback MapUnmapCallback;
249 static const uptr kFlags = 0;
250};
251template <typename AddressSpaceView>
252using PrimaryAllocatorASVT = SizeClassAllocator32<AP32<AddressSpaceView> >;
253using PrimaryAllocator = PrimaryAllocatorASVT<LocalAddressSpaceView>;
254#endif // SANITIZER_CAN_USE_ALLOCATOR64
255
256static const uptr kNumberOfSizeClasses = SizeClassMap::kNumClasses;
257
258template <typename AddressSpaceView>
259using AsanAllocatorASVT =
260 CombinedAllocator<PrimaryAllocatorASVT<AddressSpaceView>>;
261using AsanAllocator = AsanAllocatorASVT<LocalAddressSpaceView>;
262using AllocatorCache = AsanAllocator::AllocatorCache;
263
264struct AsanThreadLocalMallocStorage {
265 uptr quarantine_cache[16];
266 AllocatorCache allocator_cache;
267 void CommitBack();
268 private:
269 // These objects are allocated via mmap() and are zero-initialized.
270 AsanThreadLocalMallocStorage() {}
271};
272
273void *asan_memalign(uptr alignment, uptr size, BufferedStackTrace *stack,
274 AllocType alloc_type);
275void asan_free(void *ptr, BufferedStackTrace *stack, AllocType alloc_type);
276void asan_delete(void *ptr, uptr size, uptr alignment,
277 BufferedStackTrace *stack, AllocType alloc_type);
278
279void *asan_malloc(uptr size, BufferedStackTrace *stack);
280void *asan_calloc(uptr nmemb, uptr size, BufferedStackTrace *stack);
281void *asan_realloc(void *p, uptr size, BufferedStackTrace *stack);
282void *asan_reallocarray(void *p, uptr nmemb, uptr size,
283 BufferedStackTrace *stack);
284void *asan_valloc(uptr size, BufferedStackTrace *stack);
285void *asan_pvalloc(uptr size, BufferedStackTrace *stack);
286
287void *asan_aligned_alloc(uptr alignment, uptr size, BufferedStackTrace *stack);
288int asan_posix_memalign(void **memptr, uptr alignment, uptr size,
289 BufferedStackTrace *stack);
290uptr asan_malloc_usable_size(const void *ptr, uptr pc, uptr bp);
291
292uptr asan_mz_size(const void *ptr);
293void asan_mz_force_lock();
294void asan_mz_force_unlock();
295
296void PrintInternalAllocatorStats();
297void AsanSoftRssLimitExceededCallback(bool exceeded);
298
299} // namespace __asan
300#endif // ASAN_ALLOCATOR_H
301