1 //===-- asan_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 AddressSanitizer, an address sanity checker.
12 // Implementation of ASan's memory allocator, 2-nd version.
13 // This variant uses the allocator from sanitizer_common, i.e. the one shared
14 // with ThreadSanitizer and MemorySanitizer.
16 //===----------------------------------------------------------------------===//
18 #include "asan_allocator.h"
19 #include "asan_mapping.h"
20 #include "asan_poisoning.h"
21 #include "asan_report.h"
22 #include "asan_stack.h"
23 #include "asan_thread.h"
24 #include "sanitizer_common/sanitizer_allocator_interface.h"
25 #include "sanitizer_common/sanitizer_flags.h"
26 #include "sanitizer_common/sanitizer_internal_defs.h"
27 #include "sanitizer_common/sanitizer_list.h"
28 #include "sanitizer_common/sanitizer_stackdepot.h"
29 #include "sanitizer_common/sanitizer_quarantine.h"
30 #include "lsan/lsan_common.h"
34 // Valid redzone sizes are 16, 32, 64, ... 2048, so we encode them in 3 bits.
35 // We use adaptive redzones: for larger allocation larger redzones are used.
36 static u32 RZLog2Size(u32 rz_log) {
41 static u32 RZSize2Log(u32 rz_size) {
42 CHECK_GE(rz_size, 16);
43 CHECK_LE(rz_size, 2048);
44 CHECK(IsPowerOfTwo(rz_size));
45 u32 res = Log2(rz_size) - 4;
46 CHECK_EQ(rz_size, RZLog2Size(res));
50 static AsanAllocator &get_allocator();
52 // The memory chunk allocated from the underlying allocator looks like this:
53 // L L L L L L H H U U U U U U R R
54 // L -- left redzone words (0 or more bytes)
55 // H -- ChunkHeader (16 bytes), which is also a part of the left redzone.
57 // R -- right redzone (0 or more bytes)
58 // ChunkBase consists of ChunkHeader and other bytes that overlap with user
61 // If the left redzone is greater than the ChunkHeader size we store a magic
62 // value in the first uptr word of the memory block and store the address of
63 // ChunkBase in the next uptr.
64 // M B L L L L L L L L L H H U U U U U U
66 // ---------------------|
67 // M -- magic value kAllocBegMagic
68 // B -- address of ChunkHeader pointing to the first 'H'
69 static const uptr kAllocBegMagic = 0xCC6E96B9;
73 u32 chunk_state : 8; // Must be first.
77 u32 from_memalign : 1;
82 // This field is used for small sizes. For large sizes it is equal to
83 // SizeClassMap::kMaxSize and the actual size is stored in the
84 // SecondaryAllocator's metadata.
85 u32 user_requested_size;
89 struct ChunkBase : ChunkHeader {
90 // Header2, intersects with user memory.
94 static const uptr kChunkHeaderSize = sizeof(ChunkHeader);
95 static const uptr kChunkHeader2Size = sizeof(ChunkBase) - kChunkHeaderSize;
96 COMPILER_CHECK(kChunkHeaderSize == 16);
97 COMPILER_CHECK(kChunkHeader2Size <= 16);
99 // Every chunk of memory allocated by this allocator can be in one of 3 states:
100 // CHUNK_AVAILABLE: the chunk is in the free list and ready to be allocated.
101 // CHUNK_ALLOCATED: the chunk is allocated and not yet freed.
102 // CHUNK_QUARANTINE: the chunk was freed and put into quarantine zone.
104 CHUNK_AVAILABLE = 0, // 0 is the default value even if we didn't set it.
109 struct AsanChunk: ChunkBase {
110 uptr Beg() { return reinterpret_cast<uptr>(this) + kChunkHeaderSize; }
111 uptr UsedSize(bool locked_version = false) {
112 if (user_requested_size != SizeClassMap::kMaxSize)
113 return user_requested_size;
114 return *reinterpret_cast<uptr *>(
115 get_allocator().GetMetaData(AllocBeg(locked_version)));
117 void *AllocBeg(bool locked_version = false) {
120 return get_allocator().GetBlockBeginFastLocked(
121 reinterpret_cast<void *>(this));
122 return get_allocator().GetBlockBegin(reinterpret_cast<void *>(this));
124 return reinterpret_cast<void*>(Beg() - RZLog2Size(rz_log));
126 bool AddrIsInside(uptr addr, bool locked_version = false) {
127 return (addr >= Beg()) && (addr < Beg() + UsedSize(locked_version));
131 struct QuarantineCallback {
132 explicit QuarantineCallback(AllocatorCache *cache)
136 void Recycle(AsanChunk *m) {
137 CHECK_EQ(m->chunk_state, CHUNK_QUARANTINE);
138 atomic_store((atomic_uint8_t*)m, CHUNK_AVAILABLE, memory_order_relaxed);
139 CHECK_NE(m->alloc_tid, kInvalidTid);
140 CHECK_NE(m->free_tid, kInvalidTid);
141 PoisonShadow(m->Beg(),
142 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY),
143 kAsanHeapLeftRedzoneMagic);
144 void *p = reinterpret_cast<void *>(m->AllocBeg());
146 uptr *alloc_magic = reinterpret_cast<uptr *>(p);
147 CHECK_EQ(alloc_magic[0], kAllocBegMagic);
148 // Clear the magic value, as allocator internals may overwrite the
149 // contents of deallocated chunk, confusing GetAsanChunk lookup.
151 CHECK_EQ(alloc_magic[1], reinterpret_cast<uptr>(m));
155 AsanStats &thread_stats = GetCurrentThreadStats();
156 thread_stats.real_frees++;
157 thread_stats.really_freed += m->UsedSize();
159 get_allocator().Deallocate(cache_, p);
162 void *Allocate(uptr size) {
163 return get_allocator().Allocate(cache_, size, 1, false);
166 void Deallocate(void *p) {
167 get_allocator().Deallocate(cache_, p);
170 AllocatorCache *cache_;
173 typedef Quarantine<QuarantineCallback, AsanChunk> AsanQuarantine;
174 typedef AsanQuarantine::Cache QuarantineCache;
176 void AsanMapUnmapCallback::OnMap(uptr p, uptr size) const {
177 PoisonShadow(p, size, kAsanHeapLeftRedzoneMagic);
179 AsanStats &thread_stats = GetCurrentThreadStats();
180 thread_stats.mmaps++;
181 thread_stats.mmaped += size;
183 void AsanMapUnmapCallback::OnUnmap(uptr p, uptr size) const {
184 PoisonShadow(p, size, 0);
185 // We are about to unmap a chunk of user memory.
186 // Mark the corresponding shadow memory as not needed.
187 FlushUnneededASanShadowMemory(p, size);
189 AsanStats &thread_stats = GetCurrentThreadStats();
190 thread_stats.munmaps++;
191 thread_stats.munmaped += size;
194 // We can not use THREADLOCAL because it is not supported on some of the
195 // platforms we care about (OSX 10.6, Android).
196 // static THREADLOCAL AllocatorCache cache;
197 AllocatorCache *GetAllocatorCache(AsanThreadLocalMallocStorage *ms) {
199 return &ms->allocator_cache;
202 QuarantineCache *GetQuarantineCache(AsanThreadLocalMallocStorage *ms) {
204 CHECK_LE(sizeof(QuarantineCache), sizeof(ms->quarantine_cache));
205 return reinterpret_cast<QuarantineCache *>(ms->quarantine_cache);
208 void AllocatorOptions::SetFrom(const Flags *f, const CommonFlags *cf) {
209 quarantine_size_mb = f->quarantine_size_mb;
210 thread_local_quarantine_size_kb = f->thread_local_quarantine_size_kb;
211 min_redzone = f->redzone;
212 max_redzone = f->max_redzone;
213 may_return_null = cf->allocator_may_return_null;
214 alloc_dealloc_mismatch = f->alloc_dealloc_mismatch;
215 release_to_os_interval_ms = cf->allocator_release_to_os_interval_ms;
218 void AllocatorOptions::CopyTo(Flags *f, CommonFlags *cf) {
219 f->quarantine_size_mb = quarantine_size_mb;
220 f->thread_local_quarantine_size_kb = thread_local_quarantine_size_kb;
221 f->redzone = min_redzone;
222 f->max_redzone = max_redzone;
223 cf->allocator_may_return_null = may_return_null;
224 f->alloc_dealloc_mismatch = alloc_dealloc_mismatch;
225 cf->allocator_release_to_os_interval_ms = release_to_os_interval_ms;
229 static const uptr kMaxAllowedMallocSize =
230 FIRST_32_SECOND_64(3UL << 30, 1ULL << 40);
232 AsanAllocator allocator;
233 AsanQuarantine quarantine;
234 StaticSpinMutex fallback_mutex;
235 AllocatorCache fallback_allocator_cache;
236 QuarantineCache fallback_quarantine_cache;
238 // ------------------- Options --------------------------
239 atomic_uint16_t min_redzone;
240 atomic_uint16_t max_redzone;
241 atomic_uint8_t alloc_dealloc_mismatch;
243 // ------------------- Initialization ------------------------
244 explicit Allocator(LinkerInitialized)
245 : quarantine(LINKER_INITIALIZED),
246 fallback_quarantine_cache(LINKER_INITIALIZED) {}
248 void CheckOptions(const AllocatorOptions &options) const {
249 CHECK_GE(options.min_redzone, 16);
250 CHECK_GE(options.max_redzone, options.min_redzone);
251 CHECK_LE(options.max_redzone, 2048);
252 CHECK(IsPowerOfTwo(options.min_redzone));
253 CHECK(IsPowerOfTwo(options.max_redzone));
256 void SharedInitCode(const AllocatorOptions &options) {
257 CheckOptions(options);
258 quarantine.Init((uptr)options.quarantine_size_mb << 20,
259 (uptr)options.thread_local_quarantine_size_kb << 10);
260 atomic_store(&alloc_dealloc_mismatch, options.alloc_dealloc_mismatch,
261 memory_order_release);
262 atomic_store(&min_redzone, options.min_redzone, memory_order_release);
263 atomic_store(&max_redzone, options.max_redzone, memory_order_release);
266 void Initialize(const AllocatorOptions &options) {
267 allocator.Init(options.may_return_null, options.release_to_os_interval_ms);
268 SharedInitCode(options);
271 void RePoisonChunk(uptr chunk) {
272 // This could be a user-facing chunk (with redzones), or some internal
273 // housekeeping chunk, like TransferBatch. Start by assuming the former.
274 AsanChunk *ac = GetAsanChunk((void *)chunk);
275 uptr allocated_size = allocator.GetActuallyAllocatedSize((void *)ac);
276 uptr beg = ac->Beg();
277 uptr end = ac->Beg() + ac->UsedSize(true);
278 uptr chunk_end = chunk + allocated_size;
279 if (chunk < beg && beg < end && end <= chunk_end &&
280 ac->chunk_state == CHUNK_ALLOCATED) {
281 // Looks like a valid AsanChunk in use, poison redzones only.
282 PoisonShadow(chunk, beg - chunk, kAsanHeapLeftRedzoneMagic);
283 uptr end_aligned_down = RoundDownTo(end, SHADOW_GRANULARITY);
284 FastPoisonShadowPartialRightRedzone(
285 end_aligned_down, end - end_aligned_down,
286 chunk_end - end_aligned_down, kAsanHeapLeftRedzoneMagic);
288 // This is either not an AsanChunk or freed or quarantined AsanChunk.
289 // In either case, poison everything.
290 PoisonShadow(chunk, allocated_size, kAsanHeapLeftRedzoneMagic);
294 void ReInitialize(const AllocatorOptions &options) {
295 allocator.SetMayReturnNull(options.may_return_null);
296 allocator.SetReleaseToOSIntervalMs(options.release_to_os_interval_ms);
297 SharedInitCode(options);
299 // Poison all existing allocation's redzones.
300 if (CanPoisonMemory()) {
301 allocator.ForceLock();
302 allocator.ForEachChunk(
303 [](uptr chunk, void *alloc) {
304 ((Allocator *)alloc)->RePoisonChunk(chunk);
307 allocator.ForceUnlock();
311 void GetOptions(AllocatorOptions *options) const {
312 options->quarantine_size_mb = quarantine.GetSize() >> 20;
313 options->thread_local_quarantine_size_kb = quarantine.GetCacheSize() >> 10;
314 options->min_redzone = atomic_load(&min_redzone, memory_order_acquire);
315 options->max_redzone = atomic_load(&max_redzone, memory_order_acquire);
316 options->may_return_null = allocator.MayReturnNull();
317 options->alloc_dealloc_mismatch =
318 atomic_load(&alloc_dealloc_mismatch, memory_order_acquire);
319 options->release_to_os_interval_ms = allocator.ReleaseToOSIntervalMs();
322 // -------------------- Helper methods. -------------------------
323 uptr ComputeRZLog(uptr user_requested_size) {
325 user_requested_size <= 64 - 16 ? 0 :
326 user_requested_size <= 128 - 32 ? 1 :
327 user_requested_size <= 512 - 64 ? 2 :
328 user_requested_size <= 4096 - 128 ? 3 :
329 user_requested_size <= (1 << 14) - 256 ? 4 :
330 user_requested_size <= (1 << 15) - 512 ? 5 :
331 user_requested_size <= (1 << 16) - 1024 ? 6 : 7;
332 u32 min_rz = atomic_load(&min_redzone, memory_order_acquire);
333 u32 max_rz = atomic_load(&max_redzone, memory_order_acquire);
334 return Min(Max(rz_log, RZSize2Log(min_rz)), RZSize2Log(max_rz));
337 // We have an address between two chunks, and we want to report just one.
338 AsanChunk *ChooseChunk(uptr addr, AsanChunk *left_chunk,
339 AsanChunk *right_chunk) {
340 // Prefer an allocated chunk over freed chunk and freed chunk
341 // over available chunk.
342 if (left_chunk->chunk_state != right_chunk->chunk_state) {
343 if (left_chunk->chunk_state == CHUNK_ALLOCATED)
345 if (right_chunk->chunk_state == CHUNK_ALLOCATED)
347 if (left_chunk->chunk_state == CHUNK_QUARANTINE)
349 if (right_chunk->chunk_state == CHUNK_QUARANTINE)
352 // Same chunk_state: choose based on offset.
353 sptr l_offset = 0, r_offset = 0;
354 CHECK(AsanChunkView(left_chunk).AddrIsAtRight(addr, 1, &l_offset));
355 CHECK(AsanChunkView(right_chunk).AddrIsAtLeft(addr, 1, &r_offset));
356 if (l_offset < r_offset)
361 // -------------------- Allocation/Deallocation routines ---------------
362 void *Allocate(uptr size, uptr alignment, BufferedStackTrace *stack,
363 AllocType alloc_type, bool can_fill) {
364 if (UNLIKELY(!asan_inited))
366 Flags &fl = *flags();
368 const uptr min_alignment = SHADOW_GRANULARITY;
369 if (alignment < min_alignment)
370 alignment = min_alignment;
372 // We'd be happy to avoid allocating memory for zero-size requests, but
373 // some programs/tests depend on this behavior and assume that malloc
374 // would not return NULL even for zero-size allocations. Moreover, it
375 // looks like operator new should never return NULL, and results of
376 // consecutive "new" calls must be different even if the allocated size
380 CHECK(IsPowerOfTwo(alignment));
381 uptr rz_log = ComputeRZLog(size);
382 uptr rz_size = RZLog2Size(rz_log);
383 uptr rounded_size = RoundUpTo(Max(size, kChunkHeader2Size), alignment);
384 uptr needed_size = rounded_size + rz_size;
385 if (alignment > min_alignment)
386 needed_size += alignment;
387 bool using_primary_allocator = true;
388 // If we are allocating from the secondary allocator, there will be no
389 // automatic right redzone, so add the right redzone manually.
390 if (!PrimaryAllocator::CanAllocate(needed_size, alignment)) {
391 needed_size += rz_size;
392 using_primary_allocator = false;
394 CHECK(IsAligned(needed_size, min_alignment));
395 if (size > kMaxAllowedMallocSize || needed_size > kMaxAllowedMallocSize) {
396 Report("WARNING: AddressSanitizer failed to allocate 0x%zx bytes\n",
398 return allocator.ReturnNullOrDieOnBadRequest();
401 AsanThread *t = GetCurrentThread();
403 bool check_rss_limit = true;
405 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
407 allocator.Allocate(cache, needed_size, 8, false, check_rss_limit);
409 SpinMutexLock l(&fallback_mutex);
410 AllocatorCache *cache = &fallback_allocator_cache;
412 allocator.Allocate(cache, needed_size, 8, false, check_rss_limit);
415 if (!allocated) return allocator.ReturnNullOrDieOnOOM();
417 if (*(u8 *)MEM_TO_SHADOW((uptr)allocated) == 0 && CanPoisonMemory()) {
418 // Heap poisoning is enabled, but the allocator provides an unpoisoned
419 // chunk. This is possible if CanPoisonMemory() was false for some
420 // time, for example, due to flags()->start_disabled.
421 // Anyway, poison the block before using it for anything else.
422 uptr allocated_size = allocator.GetActuallyAllocatedSize(allocated);
423 PoisonShadow((uptr)allocated, allocated_size, kAsanHeapLeftRedzoneMagic);
426 uptr alloc_beg = reinterpret_cast<uptr>(allocated);
427 uptr alloc_end = alloc_beg + needed_size;
428 uptr beg_plus_redzone = alloc_beg + rz_size;
429 uptr user_beg = beg_plus_redzone;
430 if (!IsAligned(user_beg, alignment))
431 user_beg = RoundUpTo(user_beg, alignment);
432 uptr user_end = user_beg + size;
433 CHECK_LE(user_end, alloc_end);
434 uptr chunk_beg = user_beg - kChunkHeaderSize;
435 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg);
436 m->alloc_type = alloc_type;
438 u32 alloc_tid = t ? t->tid() : 0;
439 m->alloc_tid = alloc_tid;
440 CHECK_EQ(alloc_tid, m->alloc_tid); // Does alloc_tid fit into the bitfield?
441 m->free_tid = kInvalidTid;
442 m->from_memalign = user_beg != beg_plus_redzone;
443 if (alloc_beg != chunk_beg) {
444 CHECK_LE(alloc_beg+ 2 * sizeof(uptr), chunk_beg);
445 reinterpret_cast<uptr *>(alloc_beg)[0] = kAllocBegMagic;
446 reinterpret_cast<uptr *>(alloc_beg)[1] = chunk_beg;
448 if (using_primary_allocator) {
450 m->user_requested_size = size;
451 CHECK(allocator.FromPrimary(allocated));
453 CHECK(!allocator.FromPrimary(allocated));
454 m->user_requested_size = SizeClassMap::kMaxSize;
455 uptr *meta = reinterpret_cast<uptr *>(allocator.GetMetaData(allocated));
460 m->alloc_context_id = StackDepotPut(*stack);
462 uptr size_rounded_down_to_granularity =
463 RoundDownTo(size, SHADOW_GRANULARITY);
464 // Unpoison the bulk of the memory region.
465 if (size_rounded_down_to_granularity)
466 PoisonShadow(user_beg, size_rounded_down_to_granularity, 0);
467 // Deal with the end of the region if size is not aligned to granularity.
468 if (size != size_rounded_down_to_granularity && CanPoisonMemory()) {
470 (u8 *)MemToShadow(user_beg + size_rounded_down_to_granularity);
471 *shadow = fl.poison_partial ? (size & (SHADOW_GRANULARITY - 1)) : 0;
474 AsanStats &thread_stats = GetCurrentThreadStats();
475 thread_stats.mallocs++;
476 thread_stats.malloced += size;
477 thread_stats.malloced_redzones += needed_size - size;
478 if (needed_size > SizeClassMap::kMaxSize)
479 thread_stats.malloc_large++;
481 thread_stats.malloced_by_size[SizeClassMap::ClassID(needed_size)]++;
483 void *res = reinterpret_cast<void *>(user_beg);
484 if (can_fill && fl.max_malloc_fill_size) {
485 uptr fill_size = Min(size, (uptr)fl.max_malloc_fill_size);
486 REAL(memset)(res, fl.malloc_fill_byte, fill_size);
488 #if CAN_SANITIZE_LEAKS
489 m->lsan_tag = __lsan::DisabledInThisThread() ? __lsan::kIgnored
490 : __lsan::kDirectlyLeaked;
492 // Must be the last mutation of metadata in this function.
493 atomic_store((atomic_uint8_t *)m, CHUNK_ALLOCATED, memory_order_release);
494 ASAN_MALLOC_HOOK(res, size);
498 // Set quarantine flag if chunk is allocated, issue ASan error report on
499 // available and quarantined chunks. Return true on success, false otherwise.
500 bool AtomicallySetQuarantineFlagIfAllocated(AsanChunk *m, void *ptr,
501 BufferedStackTrace *stack) {
502 u8 old_chunk_state = CHUNK_ALLOCATED;
503 // Flip the chunk_state atomically to avoid race on double-free.
504 if (!atomic_compare_exchange_strong((atomic_uint8_t *)m, &old_chunk_state,
506 memory_order_acquire)) {
507 ReportInvalidFree(ptr, old_chunk_state, stack);
508 // It's not safe to push a chunk in quarantine on invalid free.
511 CHECK_EQ(CHUNK_ALLOCATED, old_chunk_state);
515 // Expects the chunk to already be marked as quarantined by using
516 // AtomicallySetQuarantineFlagIfAllocated.
517 void QuarantineChunk(AsanChunk *m, void *ptr, BufferedStackTrace *stack,
518 AllocType alloc_type) {
519 CHECK_EQ(m->chunk_state, CHUNK_QUARANTINE);
520 CHECK_GE(m->alloc_tid, 0);
521 if (SANITIZER_WORDSIZE == 64) // On 32-bits this resides in user area.
522 CHECK_EQ(m->free_tid, kInvalidTid);
523 AsanThread *t = GetCurrentThread();
524 m->free_tid = t ? t->tid() : 0;
525 m->free_context_id = StackDepotPut(*stack);
527 Flags &fl = *flags();
528 if (fl.max_free_fill_size > 0) {
529 // We have to skip the chunk header, it contains free_context_id.
530 uptr scribble_start = (uptr)m + kChunkHeaderSize + kChunkHeader2Size;
531 if (m->UsedSize() >= kChunkHeader2Size) { // Skip Header2 in user area.
532 uptr size_to_fill = m->UsedSize() - kChunkHeader2Size;
533 size_to_fill = Min(size_to_fill, (uptr)fl.max_free_fill_size);
534 REAL(memset)((void *)scribble_start, fl.free_fill_byte, size_to_fill);
538 // Poison the region.
539 PoisonShadow(m->Beg(),
540 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY),
543 AsanStats &thread_stats = GetCurrentThreadStats();
544 thread_stats.frees++;
545 thread_stats.freed += m->UsedSize();
547 // Push into quarantine.
549 AsanThreadLocalMallocStorage *ms = &t->malloc_storage();
550 AllocatorCache *ac = GetAllocatorCache(ms);
551 quarantine.Put(GetQuarantineCache(ms), QuarantineCallback(ac), m,
554 SpinMutexLock l(&fallback_mutex);
555 AllocatorCache *ac = &fallback_allocator_cache;
556 quarantine.Put(&fallback_quarantine_cache, QuarantineCallback(ac), m,
561 void Deallocate(void *ptr, uptr delete_size, BufferedStackTrace *stack,
562 AllocType alloc_type) {
563 uptr p = reinterpret_cast<uptr>(ptr);
566 uptr chunk_beg = p - kChunkHeaderSize;
567 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg);
569 // On Windows, uninstrumented DLLs may allocate memory before ASan hooks
570 // malloc. Don't report an invalid free in this case.
571 if (SANITIZER_WINDOWS &&
572 !get_allocator().PointerIsMine(ptr)) {
573 if (!IsSystemHeapAddress(p))
574 ReportFreeNotMalloced(p, stack);
580 // Must mark the chunk as quarantined before any changes to its metadata.
581 // Do not quarantine given chunk if we failed to set CHUNK_QUARANTINE flag.
582 if (!AtomicallySetQuarantineFlagIfAllocated(m, ptr, stack)) return;
584 if (m->alloc_type != alloc_type) {
585 if (atomic_load(&alloc_dealloc_mismatch, memory_order_acquire)) {
586 ReportAllocTypeMismatch((uptr)ptr, stack, (AllocType)m->alloc_type,
587 (AllocType)alloc_type);
591 if (delete_size && flags()->new_delete_type_mismatch &&
592 delete_size != m->UsedSize()) {
593 ReportNewDeleteSizeMismatch(p, delete_size, stack);
596 QuarantineChunk(m, ptr, stack, alloc_type);
599 void *Reallocate(void *old_ptr, uptr new_size, BufferedStackTrace *stack) {
600 CHECK(old_ptr && new_size);
601 uptr p = reinterpret_cast<uptr>(old_ptr);
602 uptr chunk_beg = p - kChunkHeaderSize;
603 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg);
605 AsanStats &thread_stats = GetCurrentThreadStats();
606 thread_stats.reallocs++;
607 thread_stats.realloced += new_size;
609 void *new_ptr = Allocate(new_size, 8, stack, FROM_MALLOC, true);
611 u8 chunk_state = m->chunk_state;
612 if (chunk_state != CHUNK_ALLOCATED)
613 ReportInvalidFree(old_ptr, chunk_state, stack);
614 CHECK_NE(REAL(memcpy), nullptr);
615 uptr memcpy_size = Min(new_size, m->UsedSize());
616 // If realloc() races with free(), we may start copying freed memory.
617 // However, we will report racy double-free later anyway.
618 REAL(memcpy)(new_ptr, old_ptr, memcpy_size);
619 Deallocate(old_ptr, 0, stack, FROM_MALLOC);
624 void *Calloc(uptr nmemb, uptr size, BufferedStackTrace *stack) {
625 if (CallocShouldReturnNullDueToOverflow(size, nmemb))
626 return allocator.ReturnNullOrDieOnBadRequest();
627 void *ptr = Allocate(nmemb * size, 8, stack, FROM_MALLOC, false);
628 // If the memory comes from the secondary allocator no need to clear it
629 // as it comes directly from mmap.
630 if (ptr && allocator.FromPrimary(ptr))
631 REAL(memset)(ptr, 0, nmemb * size);
635 void ReportInvalidFree(void *ptr, u8 chunk_state, BufferedStackTrace *stack) {
636 if (chunk_state == CHUNK_QUARANTINE)
637 ReportDoubleFree((uptr)ptr, stack);
639 ReportFreeNotMalloced((uptr)ptr, stack);
642 void CommitBack(AsanThreadLocalMallocStorage *ms) {
643 AllocatorCache *ac = GetAllocatorCache(ms);
644 quarantine.Drain(GetQuarantineCache(ms), QuarantineCallback(ac));
645 allocator.SwallowCache(ac);
648 // -------------------------- Chunk lookup ----------------------
650 // Assumes alloc_beg == allocator.GetBlockBegin(alloc_beg).
651 AsanChunk *GetAsanChunk(void *alloc_beg) {
652 if (!alloc_beg) return nullptr;
653 if (!allocator.FromPrimary(alloc_beg)) {
654 uptr *meta = reinterpret_cast<uptr *>(allocator.GetMetaData(alloc_beg));
655 AsanChunk *m = reinterpret_cast<AsanChunk *>(meta[1]);
658 uptr *alloc_magic = reinterpret_cast<uptr *>(alloc_beg);
659 if (alloc_magic[0] == kAllocBegMagic)
660 return reinterpret_cast<AsanChunk *>(alloc_magic[1]);
661 return reinterpret_cast<AsanChunk *>(alloc_beg);
664 AsanChunk *GetAsanChunkByAddr(uptr p) {
665 void *alloc_beg = allocator.GetBlockBegin(reinterpret_cast<void *>(p));
666 return GetAsanChunk(alloc_beg);
669 // Allocator must be locked when this function is called.
670 AsanChunk *GetAsanChunkByAddrFastLocked(uptr p) {
672 allocator.GetBlockBeginFastLocked(reinterpret_cast<void *>(p));
673 return GetAsanChunk(alloc_beg);
676 uptr AllocationSize(uptr p) {
677 AsanChunk *m = GetAsanChunkByAddr(p);
679 if (m->chunk_state != CHUNK_ALLOCATED) return 0;
680 if (m->Beg() != p) return 0;
681 return m->UsedSize();
684 AsanChunkView FindHeapChunkByAddress(uptr addr) {
685 AsanChunk *m1 = GetAsanChunkByAddr(addr);
686 if (!m1) return AsanChunkView(m1);
688 if (AsanChunkView(m1).AddrIsAtLeft(addr, 1, &offset)) {
689 // The address is in the chunk's left redzone, so maybe it is actually
690 // a right buffer overflow from the other chunk to the left.
691 // Search a bit to the left to see if there is another chunk.
692 AsanChunk *m2 = nullptr;
693 for (uptr l = 1; l < GetPageSizeCached(); l++) {
694 m2 = GetAsanChunkByAddr(addr - l);
695 if (m2 == m1) continue; // Still the same chunk.
698 if (m2 && AsanChunkView(m2).AddrIsAtRight(addr, 1, &offset))
699 m1 = ChooseChunk(addr, m2, m1);
701 return AsanChunkView(m1);
705 allocator.PrintStats();
706 quarantine.PrintStats();
710 allocator.ForceLock();
711 fallback_mutex.Lock();
715 fallback_mutex.Unlock();
716 allocator.ForceUnlock();
720 static Allocator instance(LINKER_INITIALIZED);
722 static AsanAllocator &get_allocator() {
723 return instance.allocator;
726 bool AsanChunkView::IsValid() const {
727 return chunk_ && chunk_->chunk_state != CHUNK_AVAILABLE;
729 bool AsanChunkView::IsAllocated() const {
730 return chunk_ && chunk_->chunk_state == CHUNK_ALLOCATED;
732 bool AsanChunkView::IsQuarantined() const {
733 return chunk_ && chunk_->chunk_state == CHUNK_QUARANTINE;
735 uptr AsanChunkView::Beg() const { return chunk_->Beg(); }
736 uptr AsanChunkView::End() const { return Beg() + UsedSize(); }
737 uptr AsanChunkView::UsedSize() const { return chunk_->UsedSize(); }
738 uptr AsanChunkView::AllocTid() const { return chunk_->alloc_tid; }
739 uptr AsanChunkView::FreeTid() const { return chunk_->free_tid; }
740 AllocType AsanChunkView::GetAllocType() const {
741 return (AllocType)chunk_->alloc_type;
744 static StackTrace GetStackTraceFromId(u32 id) {
746 StackTrace res = StackDepotGet(id);
751 u32 AsanChunkView::GetAllocStackId() const { return chunk_->alloc_context_id; }
752 u32 AsanChunkView::GetFreeStackId() const { return chunk_->free_context_id; }
754 StackTrace AsanChunkView::GetAllocStack() const {
755 return GetStackTraceFromId(GetAllocStackId());
758 StackTrace AsanChunkView::GetFreeStack() const {
759 return GetStackTraceFromId(GetFreeStackId());
762 void InitializeAllocator(const AllocatorOptions &options) {
763 instance.Initialize(options);
766 void ReInitializeAllocator(const AllocatorOptions &options) {
767 instance.ReInitialize(options);
770 void GetAllocatorOptions(AllocatorOptions *options) {
771 instance.GetOptions(options);
774 AsanChunkView FindHeapChunkByAddress(uptr addr) {
775 return instance.FindHeapChunkByAddress(addr);
777 AsanChunkView FindHeapChunkByAllocBeg(uptr addr) {
778 return AsanChunkView(instance.GetAsanChunk(reinterpret_cast<void*>(addr)));
781 void AsanThreadLocalMallocStorage::CommitBack() {
782 instance.CommitBack(this);
785 void PrintInternalAllocatorStats() {
786 instance.PrintStats();
789 void *asan_memalign(uptr alignment, uptr size, BufferedStackTrace *stack,
790 AllocType alloc_type) {
791 return instance.Allocate(size, alignment, stack, alloc_type, true);
794 void asan_free(void *ptr, BufferedStackTrace *stack, AllocType alloc_type) {
795 instance.Deallocate(ptr, 0, stack, alloc_type);
798 void asan_sized_free(void *ptr, uptr size, BufferedStackTrace *stack,
799 AllocType alloc_type) {
800 instance.Deallocate(ptr, size, stack, alloc_type);
803 void *asan_malloc(uptr size, BufferedStackTrace *stack) {
804 return instance.Allocate(size, 8, stack, FROM_MALLOC, true);
807 void *asan_calloc(uptr nmemb, uptr size, BufferedStackTrace *stack) {
808 return instance.Calloc(nmemb, size, stack);
811 void *asan_realloc(void *p, uptr size, BufferedStackTrace *stack) {
813 return instance.Allocate(size, 8, stack, FROM_MALLOC, true);
815 if (flags()->allocator_frees_and_returns_null_on_realloc_zero) {
816 instance.Deallocate(p, 0, stack, FROM_MALLOC);
819 // Allocate a size of 1 if we shouldn't free() on Realloc to 0
822 return instance.Reallocate(p, size, stack);
825 void *asan_valloc(uptr size, BufferedStackTrace *stack) {
826 return instance.Allocate(size, GetPageSizeCached(), stack, FROM_MALLOC, true);
829 void *asan_pvalloc(uptr size, BufferedStackTrace *stack) {
830 uptr PageSize = GetPageSizeCached();
831 size = RoundUpTo(size, PageSize);
833 // pvalloc(0) should allocate one page.
836 return instance.Allocate(size, PageSize, stack, FROM_MALLOC, true);
839 int asan_posix_memalign(void **memptr, uptr alignment, uptr size,
840 BufferedStackTrace *stack) {
841 void *ptr = instance.Allocate(size, alignment, stack, FROM_MALLOC, true);
842 CHECK(IsAligned((uptr)ptr, alignment));
847 uptr asan_malloc_usable_size(const void *ptr, uptr pc, uptr bp) {
849 uptr usable_size = instance.AllocationSize(reinterpret_cast<uptr>(ptr));
850 if (flags()->check_malloc_usable_size && (usable_size == 0)) {
851 GET_STACK_TRACE_FATAL(pc, bp);
852 ReportMallocUsableSizeNotOwned((uptr)ptr, &stack);
857 uptr asan_mz_size(const void *ptr) {
858 return instance.AllocationSize(reinterpret_cast<uptr>(ptr));
861 void asan_mz_force_lock() {
862 instance.ForceLock();
865 void asan_mz_force_unlock() {
866 instance.ForceUnlock();
869 void AsanSoftRssLimitExceededCallback(bool exceeded) {
870 instance.allocator.SetRssLimitIsExceeded(exceeded);
873 } // namespace __asan
875 // --- Implementation of LSan-specific functions --- {{{1
877 void LockAllocator() {
878 __asan::get_allocator().ForceLock();
881 void UnlockAllocator() {
882 __asan::get_allocator().ForceUnlock();
885 void GetAllocatorGlobalRange(uptr *begin, uptr *end) {
886 *begin = (uptr)&__asan::get_allocator();
887 *end = *begin + sizeof(__asan::get_allocator());
890 uptr PointsIntoChunk(void* p) {
891 uptr addr = reinterpret_cast<uptr>(p);
892 __asan::AsanChunk *m = __asan::instance.GetAsanChunkByAddrFastLocked(addr);
894 uptr chunk = m->Beg();
895 if (m->chunk_state != __asan::CHUNK_ALLOCATED)
897 if (m->AddrIsInside(addr, /*locked_version=*/true))
899 if (IsSpecialCaseOfOperatorNew0(chunk, m->UsedSize(/*locked_version*/ true),
905 uptr GetUserBegin(uptr chunk) {
906 __asan::AsanChunk *m = __asan::instance.GetAsanChunkByAddrFastLocked(chunk);
911 LsanMetadata::LsanMetadata(uptr chunk) {
912 metadata_ = reinterpret_cast<void *>(chunk - __asan::kChunkHeaderSize);
915 bool LsanMetadata::allocated() const {
916 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_);
917 return m->chunk_state == __asan::CHUNK_ALLOCATED;
920 ChunkTag LsanMetadata::tag() const {
921 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_);
922 return static_cast<ChunkTag>(m->lsan_tag);
925 void LsanMetadata::set_tag(ChunkTag value) {
926 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_);
930 uptr LsanMetadata::requested_size() const {
931 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_);
932 return m->UsedSize(/*locked_version=*/true);
935 u32 LsanMetadata::stack_trace_id() const {
936 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_);
937 return m->alloc_context_id;
940 void ForEachChunk(ForEachChunkCallback callback, void *arg) {
941 __asan::get_allocator().ForEachChunk(callback, arg);
944 IgnoreObjectResult IgnoreObjectLocked(const void *p) {
945 uptr addr = reinterpret_cast<uptr>(p);
946 __asan::AsanChunk *m = __asan::instance.GetAsanChunkByAddr(addr);
947 if (!m) return kIgnoreObjectInvalid;
948 if ((m->chunk_state == __asan::CHUNK_ALLOCATED) && m->AddrIsInside(addr)) {
949 if (m->lsan_tag == kIgnored)
950 return kIgnoreObjectAlreadyIgnored;
951 m->lsan_tag = __lsan::kIgnored;
952 return kIgnoreObjectSuccess;
954 return kIgnoreObjectInvalid;
957 } // namespace __lsan
959 // ---------------------- Interface ---------------- {{{1
960 using namespace __asan; // NOLINT
962 // ASan allocator doesn't reserve extra bytes, so normally we would
963 // just return "size". We don't want to expose our redzone sizes, etc here.
964 uptr __sanitizer_get_estimated_allocated_size(uptr size) {
968 int __sanitizer_get_ownership(const void *p) {
969 uptr ptr = reinterpret_cast<uptr>(p);
970 return instance.AllocationSize(ptr) > 0;
973 uptr __sanitizer_get_allocated_size(const void *p) {
975 uptr ptr = reinterpret_cast<uptr>(p);
976 uptr allocated_size = instance.AllocationSize(ptr);
977 // Die if p is not malloced or if it is already freed.
978 if (allocated_size == 0) {
979 GET_STACK_TRACE_FATAL_HERE;
980 ReportSanitizerGetAllocatedSizeNotOwned(ptr, &stack);
982 return allocated_size;
985 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
986 // Provide default (no-op) implementation of malloc hooks.
987 SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_malloc_hook,
988 void *ptr, uptr size) {
993 SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_free_hook, void *ptr) {