1 //===-- hwasan_allocator.cc --------------------------- ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of HWAddressSanitizer.
12 // HWAddressSanitizer allocator.
13 //===----------------------------------------------------------------------===//
15 #include "sanitizer_common/sanitizer_allocator.h"
16 #include "sanitizer_common/sanitizer_allocator_checks.h"
17 #include "sanitizer_common/sanitizer_allocator_interface.h"
18 #include "sanitizer_common/sanitizer_atomic.h"
19 #include "sanitizer_common/sanitizer_errno.h"
20 #include "sanitizer_common/sanitizer_stackdepot.h"
22 #include "hwasan_allocator.h"
23 #include "hwasan_thread.h"
24 #include "hwasan_poisoning.h"
36 u64 requested_size : 62;
41 bool HwasanChunkView::IsValid() const {
42 return metadata_ && metadata_->state != CHUNK_INVALID;
44 bool HwasanChunkView::IsAllocated() const {
45 return metadata_ && metadata_->state == CHUNK_ALLOCATED;
47 uptr HwasanChunkView::Beg() const {
50 uptr HwasanChunkView::End() const {
51 return Beg() + UsedSize();
53 uptr HwasanChunkView::UsedSize() const {
54 return metadata_->requested_size;
56 u32 HwasanChunkView::GetAllocStackId() const {
57 return metadata_->alloc_context_id;
59 u32 HwasanChunkView::GetFreeStackId() const {
60 return metadata_->free_context_id;
63 struct HwasanMapUnmapCallback {
64 void OnMap(uptr p, uptr size) const {}
65 void OnUnmap(uptr p, uptr size) const {
66 // We are about to unmap a chunk of user memory.
67 // It can return as user-requested mmap() or another thread stack.
68 // Make it accessible with zero-tagged pointer.
69 TagMemory(p, size, 0);
73 #if !defined(__aarch64__)
74 #error unsupported platform
77 static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
78 static const uptr kRegionSizeLog = 20;
79 static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
80 typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
83 static const uptr kSpaceBeg = 0;
84 static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
85 static const uptr kMetadataSize = sizeof(Metadata);
86 typedef __sanitizer::CompactSizeClassMap SizeClassMap;
87 static const uptr kRegionSizeLog = __hwasan::kRegionSizeLog;
88 typedef __hwasan::ByteMap ByteMap;
89 typedef HwasanMapUnmapCallback MapUnmapCallback;
90 static const uptr kFlags = 0;
92 typedef SizeClassAllocator32<AP32> PrimaryAllocator;
93 typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
94 typedef LargeMmapAllocator<HwasanMapUnmapCallback> SecondaryAllocator;
95 typedef CombinedAllocator<PrimaryAllocator, AllocatorCache,
96 SecondaryAllocator> Allocator;
98 static Allocator allocator;
99 static AllocatorCache fallback_allocator_cache;
100 static SpinMutex fallback_mutex;
101 static atomic_uint8_t hwasan_allocator_tagging_enabled;
103 void HwasanAllocatorInit() {
104 atomic_store_relaxed(&hwasan_allocator_tagging_enabled,
105 !flags()->disable_allocator_tagging);
106 SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
107 allocator.Init(common_flags()->allocator_release_to_os_interval_ms);
110 AllocatorCache *GetAllocatorCache(HwasanThreadLocalMallocStorage *ms) {
112 CHECK_LE(sizeof(AllocatorCache), sizeof(ms->allocator_cache));
113 return reinterpret_cast<AllocatorCache *>(ms->allocator_cache);
116 void HwasanThreadLocalMallocStorage::CommitBack() {
117 allocator.SwallowCache(GetAllocatorCache(this));
120 static void *HwasanAllocate(StackTrace *stack, uptr size, uptr alignment,
122 alignment = Max(alignment, kShadowAlignment);
123 size = RoundUpTo(size, kShadowAlignment);
125 if (size > kMaxAllowedMallocSize) {
126 Report("WARNING: HWAddressSanitizer failed to allocate %p bytes\n",
128 return Allocator::FailureHandler::OnBadRequest();
130 HwasanThread *t = GetCurrentThread();
133 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
134 allocated = allocator.Allocate(cache, size, alignment);
136 SpinMutexLock l(&fallback_mutex);
137 AllocatorCache *cache = &fallback_allocator_cache;
138 allocated = allocator.Allocate(cache, size, alignment);
141 reinterpret_cast<Metadata *>(allocator.GetMetaData(allocated));
142 meta->state = CHUNK_ALLOCATED;
143 meta->requested_size = size;
144 meta->alloc_context_id = StackDepotPut(*stack);
146 internal_memset(allocated, 0, size);
148 void *user_ptr = (flags()->tag_in_malloc &&
149 atomic_load_relaxed(&hwasan_allocator_tagging_enabled))
150 ? (void *)TagMemoryAligned((uptr)allocated, size, 0xBB)
153 HWASAN_MALLOC_HOOK(user_ptr, size);
157 void HwasanDeallocate(StackTrace *stack, void *user_ptr) {
159 HWASAN_FREE_HOOK(user_ptr);
161 void *p = GetAddressFromPointer(user_ptr);
162 Metadata *meta = reinterpret_cast<Metadata *>(allocator.GetMetaData(p));
163 uptr size = meta->requested_size;
164 meta->state = CHUNK_FREE;
165 meta->requested_size = 0;
166 meta->free_context_id = StackDepotPut(*stack);
167 // This memory will not be reused by anyone else, so we are free to keep it
169 if (flags()->tag_in_free &&
170 atomic_load_relaxed(&hwasan_allocator_tagging_enabled))
171 TagMemoryAligned((uptr)p, size, 0xBC);
172 HwasanThread *t = GetCurrentThread();
174 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
175 allocator.Deallocate(cache, p);
177 SpinMutexLock l(&fallback_mutex);
178 AllocatorCache *cache = &fallback_allocator_cache;
179 allocator.Deallocate(cache, p);
183 void *HwasanReallocate(StackTrace *stack, void *user_old_p, uptr new_size,
185 alignment = Max(alignment, kShadowAlignment);
186 new_size = RoundUpTo(new_size, kShadowAlignment);
188 void *old_p = GetAddressFromPointer(user_old_p);
189 Metadata *meta = reinterpret_cast<Metadata*>(allocator.GetMetaData(old_p));
190 uptr old_size = meta->requested_size;
191 uptr actually_allocated_size = allocator.GetActuallyAllocatedSize(old_p);
192 if (new_size <= actually_allocated_size) {
193 // We are not reallocating here.
194 // FIXME: update stack trace for the allocation?
195 meta->requested_size = new_size;
196 if (!atomic_load_relaxed(&hwasan_allocator_tagging_enabled))
198 if (flags()->retag_in_realloc)
199 return (void *)TagMemoryAligned((uptr)old_p, new_size, 0xCC);
200 if (new_size > old_size) {
201 tag_t tag = GetTagFromPointer((uptr)user_old_p);
202 TagMemoryAligned((uptr)old_p + old_size, new_size - old_size, tag);
206 uptr memcpy_size = Min(new_size, old_size);
207 void *new_p = HwasanAllocate(stack, new_size, alignment, false /*zeroise*/);
209 internal_memcpy(new_p, old_p, memcpy_size);
210 HwasanDeallocate(stack, old_p);
215 HwasanChunkView FindHeapChunkByAddress(uptr address) {
216 void *block = allocator.GetBlockBegin(reinterpret_cast<void*>(address));
218 return HwasanChunkView();
220 reinterpret_cast<Metadata*>(allocator.GetMetaData(block));
221 return HwasanChunkView(reinterpret_cast<uptr>(block), metadata);
224 static uptr AllocationSize(const void *user_ptr) {
225 const void *p = GetAddressFromPointer(user_ptr);
227 const void *beg = allocator.GetBlockBegin(p);
228 if (beg != p) return 0;
229 Metadata *b = (Metadata *)allocator.GetMetaData(p);
230 return b->requested_size;
233 void *hwasan_malloc(uptr size, StackTrace *stack) {
234 return SetErrnoOnNull(HwasanAllocate(stack, size, sizeof(u64), false));
237 void *hwasan_calloc(uptr nmemb, uptr size, StackTrace *stack) {
238 if (UNLIKELY(CheckForCallocOverflow(size, nmemb)))
239 return SetErrnoOnNull(Allocator::FailureHandler::OnBadRequest());
240 return SetErrnoOnNull(HwasanAllocate(stack, nmemb * size, sizeof(u64), true));
243 void *hwasan_realloc(void *ptr, uptr size, StackTrace *stack) {
245 return SetErrnoOnNull(HwasanAllocate(stack, size, sizeof(u64), false));
247 HwasanDeallocate(stack, ptr);
250 return SetErrnoOnNull(HwasanReallocate(stack, ptr, size, sizeof(u64)));
253 void *hwasan_valloc(uptr size, StackTrace *stack) {
254 return SetErrnoOnNull(HwasanAllocate(stack, size, GetPageSizeCached(), false));
257 void *hwasan_pvalloc(uptr size, StackTrace *stack) {
258 uptr PageSize = GetPageSizeCached();
259 if (UNLIKELY(CheckForPvallocOverflow(size, PageSize))) {
260 errno = errno_ENOMEM;
261 return Allocator::FailureHandler::OnBadRequest();
263 // pvalloc(0) should allocate one page.
264 size = size ? RoundUpTo(size, PageSize) : PageSize;
265 return SetErrnoOnNull(HwasanAllocate(stack, size, PageSize, false));
268 void *hwasan_aligned_alloc(uptr alignment, uptr size, StackTrace *stack) {
269 if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(alignment, size))) {
270 errno = errno_EINVAL;
271 return Allocator::FailureHandler::OnBadRequest();
273 return SetErrnoOnNull(HwasanAllocate(stack, size, alignment, false));
276 void *hwasan_memalign(uptr alignment, uptr size, StackTrace *stack) {
277 if (UNLIKELY(!IsPowerOfTwo(alignment))) {
278 errno = errno_EINVAL;
279 return Allocator::FailureHandler::OnBadRequest();
281 return SetErrnoOnNull(HwasanAllocate(stack, size, alignment, false));
284 int hwasan_posix_memalign(void **memptr, uptr alignment, uptr size,
286 if (UNLIKELY(!CheckPosixMemalignAlignment(alignment))) {
287 Allocator::FailureHandler::OnBadRequest();
290 void *ptr = HwasanAllocate(stack, size, alignment, false);
293 CHECK(IsAligned((uptr)ptr, alignment));
298 } // namespace __hwasan
300 using namespace __hwasan;
302 void __hwasan_enable_allocator_tagging() {
303 atomic_store_relaxed(&hwasan_allocator_tagging_enabled, 1);
306 void __hwasan_disable_allocator_tagging() {
307 atomic_store_relaxed(&hwasan_allocator_tagging_enabled, 0);
310 uptr __sanitizer_get_current_allocated_bytes() {
311 uptr stats[AllocatorStatCount];
312 allocator.GetStats(stats);
313 return stats[AllocatorStatAllocated];
316 uptr __sanitizer_get_heap_size() {
317 uptr stats[AllocatorStatCount];
318 allocator.GetStats(stats);
319 return stats[AllocatorStatMapped];
322 uptr __sanitizer_get_free_bytes() { return 1; }
324 uptr __sanitizer_get_unmapped_bytes() { return 1; }
326 uptr __sanitizer_get_estimated_allocated_size(uptr size) { return size; }
328 int __sanitizer_get_ownership(const void *p) { return AllocationSize(p) != 0; }
330 uptr __sanitizer_get_allocated_size(const void *p) { return AllocationSize(p); }