asan_allocator2.cc revision 589dcdaa520de1033a0f6112c9b67ab9eb7931af
1//===-- asan_allocator2.cc ------------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file is a part of AddressSanitizer, an address sanity checker. 11// 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. 15// 16// Status: under development, not enabled by default yet. 17//===----------------------------------------------------------------------===// 18#include "asan_allocator.h" 19#if ASAN_ALLOCATOR_VERSION == 2 20 21#include "asan_mapping.h" 22#include "asan_report.h" 23#include "asan_thread.h" 24#include "asan_thread_registry.h" 25#include "sanitizer_common/sanitizer_allocator.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 31namespace __asan { 32 33struct AsanMapUnmapCallback { 34 void OnMap(uptr p, uptr size) const { 35 PoisonShadow(p, size, kAsanHeapLeftRedzoneMagic); 36 // Statistics. 37 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 38 thread_stats.mmaps++; 39 thread_stats.mmaped += size; 40 } 41 void OnUnmap(uptr p, uptr size) const { 42 PoisonShadow(p, size, 0); 43 // We are about to unmap a chunk of user memory. 44 // Mark the corresponding shadow memory as not needed. 45 // Since asan's mapping is compacting, the shadow chunk may be 46 // not page-aligned, so we only flush the page-aligned portion. 47 uptr page_size = GetPageSizeCached(); 48 uptr shadow_beg = RoundUpTo(MemToShadow(p), page_size); 49 uptr shadow_end = RoundDownTo(MemToShadow(p + size), page_size); 50 FlushUnneededShadowMemory(shadow_beg, shadow_end - shadow_beg); 51 // Statistics. 52 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 53 thread_stats.munmaps++; 54 thread_stats.munmaped += size; 55 } 56}; 57 58#if SANITIZER_WORDSIZE == 64 59#if defined(__powerpc64__) 60const uptr kAllocatorSpace = 0xa0000000000ULL; 61#else 62const uptr kAllocatorSpace = 0x600000000000ULL; 63#endif 64const uptr kAllocatorSize = 0x10000000000ULL; // 1T. 65typedef DefaultSizeClassMap SizeClassMap; 66typedef SizeClassAllocator64<kAllocatorSpace, kAllocatorSize, 0 /*metadata*/, 67 SizeClassMap, AsanMapUnmapCallback> PrimaryAllocator; 68#elif SANITIZER_WORDSIZE == 32 69static const u64 kAddressSpaceSize = 1ULL << 32; 70typedef CompactSizeClassMap SizeClassMap; 71typedef SizeClassAllocator32<0, kAddressSpaceSize, 16, 72 SizeClassMap, AsanMapUnmapCallback> PrimaryAllocator; 73#endif 74 75typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache; 76typedef LargeMmapAllocator<AsanMapUnmapCallback> SecondaryAllocator; 77typedef CombinedAllocator<PrimaryAllocator, AllocatorCache, 78 SecondaryAllocator> Allocator; 79 80// We can not use THREADLOCAL because it is not supported on some of the 81// platforms we care about (OSX 10.6, Android). 82// static THREADLOCAL AllocatorCache cache; 83AllocatorCache *GetAllocatorCache(AsanThreadLocalMallocStorage *ms) { 84 CHECK(ms); 85 CHECK_LE(sizeof(AllocatorCache), sizeof(ms->allocator2_cache)); 86 return reinterpret_cast<AllocatorCache *>(ms->allocator2_cache); 87} 88 89static Allocator allocator; 90 91static const uptr kMaxAllowedMallocSize = 92 FIRST_32_SECOND_64(3UL << 30, 8UL << 30); 93 94static const uptr kMaxThreadLocalQuarantine = 95 FIRST_32_SECOND_64(1 << 18, 1 << 20); 96 97// Every chunk of memory allocated by this allocator can be in one of 3 states: 98// CHUNK_AVAILABLE: the chunk is in the free list and ready to be allocated. 99// CHUNK_ALLOCATED: the chunk is allocated and not yet freed. 100// CHUNK_QUARANTINE: the chunk was freed and put into quarantine zone. 101enum { 102 CHUNK_AVAILABLE = 0, // 0 is the default value even if we didn't set it. 103 CHUNK_ALLOCATED = 2, 104 CHUNK_QUARANTINE = 3 105}; 106 107// Valid redzone sizes are 16, 32, 64, ... 2048, so we encode them in 3 bits. 108// We use adaptive redzones: for larger allocation larger redzones are used. 109static u32 RZLog2Size(u32 rz_log) { 110 CHECK_LT(rz_log, 8); 111 return 16 << rz_log; 112} 113 114static u32 RZSize2Log(u32 rz_size) { 115 CHECK_GE(rz_size, 16); 116 CHECK_LE(rz_size, 2048); 117 CHECK(IsPowerOfTwo(rz_size)); 118 u32 res = __builtin_ctz(rz_size) - 4; 119 CHECK_EQ(rz_size, RZLog2Size(res)); 120 return res; 121} 122 123static uptr ComputeRZLog(uptr user_requested_size) { 124 u32 rz_log = 125 user_requested_size <= 64 - 16 ? 0 : 126 user_requested_size <= 128 - 32 ? 1 : 127 user_requested_size <= 512 - 64 ? 2 : 128 user_requested_size <= 4096 - 128 ? 3 : 129 user_requested_size <= (1 << 14) - 256 ? 4 : 130 user_requested_size <= (1 << 15) - 512 ? 5 : 131 user_requested_size <= (1 << 16) - 1024 ? 6 : 7; 132 return Max(rz_log, RZSize2Log(flags()->redzone)); 133} 134 135// The memory chunk allocated from the underlying allocator looks like this: 136// L L L L L L H H U U U U U U R R 137// L -- left redzone words (0 or more bytes) 138// H -- ChunkHeader (16 bytes), which is also a part of the left redzone. 139// U -- user memory. 140// R -- right redzone (0 or more bytes) 141// ChunkBase consists of ChunkHeader and other bytes that overlap with user 142// memory. 143 144// If a memory chunk is allocated by memalign and we had to increase the 145// allocation size to achieve the proper alignment, then we store this magic 146// value in the first uptr word of the memory block and store the address of 147// ChunkBase in the next uptr. 148// M B ? ? ? L L L L L L H H U U U U U U 149// M -- magic value kMemalignMagic 150// B -- address of ChunkHeader pointing to the first 'H' 151static const uptr kMemalignMagic = 0xCC6E96B9; 152 153struct ChunkHeader { 154 // 1-st 8 bytes. 155 u32 chunk_state : 8; // Must be first. 156 u32 alloc_tid : 24; 157 158 u32 free_tid : 24; 159 u32 from_memalign : 1; 160 u32 alloc_type : 2; 161 u32 rz_log : 3; 162 // 2-nd 8 bytes 163 // This field is used for small sizes. For large sizes it is equal to 164 // SizeClassMap::kMaxSize and the actual size is stored in the 165 // SecondaryAllocator's metadata. 166 u32 user_requested_size; 167 u32 alloc_context_id; 168}; 169 170struct ChunkBase : ChunkHeader { 171 // Header2, intersects with user memory. 172 AsanChunk *next; 173 u32 free_context_id; 174}; 175 176static const uptr kChunkHeaderSize = sizeof(ChunkHeader); 177static const uptr kChunkHeader2Size = sizeof(ChunkBase) - kChunkHeaderSize; 178COMPILER_CHECK(kChunkHeaderSize == 16); 179COMPILER_CHECK(kChunkHeader2Size <= 16); 180 181struct AsanChunk: ChunkBase { 182 uptr Beg() { return reinterpret_cast<uptr>(this) + kChunkHeaderSize; } 183 uptr UsedSize() { 184 if (user_requested_size != SizeClassMap::kMaxSize) 185 return user_requested_size; 186 return *reinterpret_cast<uptr *>(allocator.GetMetaData(AllocBeg())); 187 } 188 void *AllocBeg() { 189 if (from_memalign) 190 return allocator.GetBlockBegin(reinterpret_cast<void *>(this)); 191 return reinterpret_cast<void*>(Beg() - RZLog2Size(rz_log)); 192 } 193 // We store the alloc/free stack traces in the chunk itself. 194 u32 *AllocStackBeg() { 195 return (u32*)(Beg() - RZLog2Size(rz_log)); 196 } 197 uptr AllocStackSize() { 198 CHECK_LE(RZLog2Size(rz_log), kChunkHeaderSize); 199 return (RZLog2Size(rz_log) - kChunkHeaderSize) / sizeof(u32); 200 } 201 u32 *FreeStackBeg() { 202 return (u32*)(Beg() + kChunkHeader2Size); 203 } 204 uptr FreeStackSize() { 205 if (user_requested_size < kChunkHeader2Size) return 0; 206 uptr available = RoundUpTo(user_requested_size, SHADOW_GRANULARITY); 207 return (available - kChunkHeader2Size) / sizeof(u32); 208 } 209}; 210 211uptr AsanChunkView::Beg() { return chunk_->Beg(); } 212uptr AsanChunkView::End() { return Beg() + UsedSize(); } 213uptr AsanChunkView::UsedSize() { return chunk_->UsedSize(); } 214uptr AsanChunkView::AllocTid() { return chunk_->alloc_tid; } 215uptr AsanChunkView::FreeTid() { return chunk_->free_tid; } 216 217static void GetStackTraceFromId(u32 id, StackTrace *stack) { 218 CHECK(id); 219 uptr size = 0; 220 const uptr *trace = StackDepotGet(id, &size); 221 CHECK_LT(size, kStackTraceMax); 222 internal_memcpy(stack->trace, trace, sizeof(uptr) * size); 223 stack->size = size; 224} 225 226void AsanChunkView::GetAllocStack(StackTrace *stack) { 227 if (flags()->use_stack_depot) 228 GetStackTraceFromId(chunk_->alloc_context_id, stack); 229 else 230 StackTrace::UncompressStack(stack, chunk_->AllocStackBeg(), 231 chunk_->AllocStackSize()); 232} 233 234void AsanChunkView::GetFreeStack(StackTrace *stack) { 235 if (flags()->use_stack_depot) 236 GetStackTraceFromId(chunk_->free_context_id, stack); 237 else 238 StackTrace::UncompressStack(stack, chunk_->FreeStackBeg(), 239 chunk_->FreeStackSize()); 240} 241 242struct QuarantineCallback; 243typedef Quarantine<QuarantineCallback, AsanChunk> AsanQuarantine; 244typedef AsanQuarantine::Cache QuarantineCache; 245static AsanQuarantine quarantine(LINKER_INITIALIZED); 246static QuarantineCache fallback_quarantine_cache(LINKER_INITIALIZED); 247static AllocatorCache fallback_allocator_cache; 248static SpinMutex fallback_mutex; 249 250QuarantineCache *GetQuarantineCache(AsanThreadLocalMallocStorage *ms) { 251 CHECK(ms); 252 CHECK_LE(sizeof(QuarantineCache), sizeof(ms->quarantine_cache)); 253 return reinterpret_cast<QuarantineCache *>(ms->quarantine_cache); 254} 255 256struct QuarantineCallback { 257 explicit QuarantineCallback(AllocatorCache *cache) 258 : cache_(cache) { 259 } 260 261 void Recycle(AsanChunk *m) { 262 CHECK(m->chunk_state == CHUNK_QUARANTINE); 263 m->chunk_state = CHUNK_AVAILABLE; 264 CHECK_NE(m->alloc_tid, kInvalidTid); 265 CHECK_NE(m->free_tid, kInvalidTid); 266 PoisonShadow(m->Beg(), 267 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY), 268 kAsanHeapLeftRedzoneMagic); 269 void *p = reinterpret_cast<void *>(m->AllocBeg()); 270 if (m->from_memalign) { 271 uptr *memalign_magic = reinterpret_cast<uptr *>(p); 272 CHECK_EQ(memalign_magic[0], kMemalignMagic); 273 CHECK_EQ(memalign_magic[1], reinterpret_cast<uptr>(m)); 274 } 275 276 // Statistics. 277 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 278 thread_stats.real_frees++; 279 thread_stats.really_freed += m->UsedSize(); 280 281 allocator.Deallocate(cache_, p); 282 } 283 284 void *Allocate(uptr size) { 285 return allocator.Allocate(cache_, size, 1, false); 286 } 287 288 void Deallocate(void *p) { 289 allocator.Deallocate(cache_, p); 290 } 291 292 AllocatorCache *cache_; 293}; 294 295void InitializeAllocator() { 296 allocator.Init(); 297 quarantine.Init((uptr)flags()->quarantine_size, kMaxThreadLocalQuarantine); 298} 299 300static void *Allocate(uptr size, uptr alignment, StackTrace *stack, 301 AllocType alloc_type) { 302 if (!asan_inited) 303 __asan_init(); 304 CHECK(stack); 305 const uptr min_alignment = SHADOW_GRANULARITY; 306 if (alignment < min_alignment) 307 alignment = min_alignment; 308 if (size == 0) { 309 // We'd be happy to avoid allocating memory for zero-size requests, but 310 // some programs/tests depend on this behavior and assume that malloc would 311 // not return NULL even for zero-size allocations. Moreover, it looks like 312 // operator new should never return NULL, and results of consecutive "new" 313 // calls must be different even if the allocated size is zero. 314 size = 1; 315 } 316 CHECK(IsPowerOfTwo(alignment)); 317 uptr rz_log = ComputeRZLog(size); 318 uptr rz_size = RZLog2Size(rz_log); 319 uptr rounded_size = RoundUpTo(size, alignment); 320 if (rounded_size < kChunkHeader2Size) 321 rounded_size = kChunkHeader2Size; 322 uptr needed_size = rounded_size + rz_size; 323 if (alignment > min_alignment) 324 needed_size += alignment; 325 bool using_primary_allocator = true; 326 // If we are allocating from the secondary allocator, there will be no 327 // automatic right redzone, so add the right redzone manually. 328 if (!PrimaryAllocator::CanAllocate(needed_size, alignment)) { 329 needed_size += rz_size; 330 using_primary_allocator = false; 331 } 332 CHECK(IsAligned(needed_size, min_alignment)); 333 if (size > kMaxAllowedMallocSize || needed_size > kMaxAllowedMallocSize) { 334 Report("WARNING: AddressSanitizer failed to allocate %p bytes\n", 335 (void*)size); 336 return 0; 337 } 338 339 AsanThread *t = asanThreadRegistry().GetCurrent(); 340 void *allocated; 341 if (t) { 342 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage()); 343 allocated = allocator.Allocate(cache, needed_size, 8, false); 344 } else { 345 SpinMutexLock l(&fallback_mutex); 346 AllocatorCache *cache = &fallback_allocator_cache; 347 allocated = allocator.Allocate(cache, needed_size, 8, false); 348 } 349 uptr alloc_beg = reinterpret_cast<uptr>(allocated); 350 // Clear the first allocated word (an old kMemalignMagic may still be there). 351 reinterpret_cast<uptr *>(alloc_beg)[0] = 0; 352 uptr alloc_end = alloc_beg + needed_size; 353 uptr beg_plus_redzone = alloc_beg + rz_size; 354 uptr user_beg = beg_plus_redzone; 355 if (!IsAligned(user_beg, alignment)) 356 user_beg = RoundUpTo(user_beg, alignment); 357 uptr user_end = user_beg + size; 358 CHECK_LE(user_end, alloc_end); 359 uptr chunk_beg = user_beg - kChunkHeaderSize; 360 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 361 m->chunk_state = CHUNK_ALLOCATED; 362 m->alloc_type = alloc_type; 363 m->rz_log = rz_log; 364 u32 alloc_tid = t ? t->tid() : 0; 365 m->alloc_tid = alloc_tid; 366 CHECK_EQ(alloc_tid, m->alloc_tid); // Does alloc_tid fit into the bitfield? 367 m->free_tid = kInvalidTid; 368 m->from_memalign = user_beg != beg_plus_redzone; 369 if (m->from_memalign) { 370 CHECK_LE(beg_plus_redzone + 2 * sizeof(uptr), user_beg); 371 uptr *memalign_magic = reinterpret_cast<uptr *>(alloc_beg); 372 memalign_magic[0] = kMemalignMagic; 373 memalign_magic[1] = chunk_beg; 374 } 375 if (using_primary_allocator) { 376 CHECK(size); 377 m->user_requested_size = size; 378 CHECK(allocator.FromPrimary(allocated)); 379 } else { 380 CHECK(!allocator.FromPrimary(allocated)); 381 m->user_requested_size = SizeClassMap::kMaxSize; 382 uptr *meta = reinterpret_cast<uptr *>(allocator.GetMetaData(allocated)); 383 meta[0] = size; 384 meta[1] = chunk_beg; 385 } 386 387 if (flags()->use_stack_depot) { 388 m->alloc_context_id = StackDepotPut(stack->trace, stack->size); 389 } else { 390 m->alloc_context_id = 0; 391 StackTrace::CompressStack(stack, m->AllocStackBeg(), m->AllocStackSize()); 392 } 393 394 uptr size_rounded_down_to_granularity = RoundDownTo(size, SHADOW_GRANULARITY); 395 // Unpoison the bulk of the memory region. 396 if (size_rounded_down_to_granularity) 397 PoisonShadow(user_beg, size_rounded_down_to_granularity, 0); 398 // Deal with the end of the region if size is not aligned to granularity. 399 if (size != size_rounded_down_to_granularity && flags()->poison_heap) { 400 u8 *shadow = (u8*)MemToShadow(user_beg + size_rounded_down_to_granularity); 401 *shadow = size & (SHADOW_GRANULARITY - 1); 402 } 403 404 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 405 thread_stats.mallocs++; 406 thread_stats.malloced += size; 407 thread_stats.malloced_redzones += needed_size - size; 408 uptr class_id = Min(kNumberOfSizeClasses, SizeClassMap::ClassID(needed_size)); 409 thread_stats.malloced_by_size[class_id]++; 410 if (needed_size > SizeClassMap::kMaxSize) 411 thread_stats.malloc_large++; 412 413 void *res = reinterpret_cast<void *>(user_beg); 414 ASAN_MALLOC_HOOK(res, size); 415 return res; 416} 417 418static void Deallocate(void *ptr, StackTrace *stack, AllocType alloc_type) { 419 uptr p = reinterpret_cast<uptr>(ptr); 420 if (p == 0) return; 421 ASAN_FREE_HOOK(ptr); 422 uptr chunk_beg = p - kChunkHeaderSize; 423 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 424 425 // Flip the chunk_state atomically to avoid race on double-free. 426 u8 old_chunk_state = atomic_exchange((atomic_uint8_t*)m, CHUNK_QUARANTINE, 427 memory_order_relaxed); 428 429 if (old_chunk_state == CHUNK_QUARANTINE) 430 ReportDoubleFree((uptr)ptr, stack); 431 else if (old_chunk_state != CHUNK_ALLOCATED) 432 ReportFreeNotMalloced((uptr)ptr, stack); 433 CHECK(old_chunk_state == CHUNK_ALLOCATED); 434 if (m->alloc_type != alloc_type && flags()->alloc_dealloc_mismatch) 435 ReportAllocTypeMismatch((uptr)ptr, stack, 436 (AllocType)m->alloc_type, (AllocType)alloc_type); 437 438 CHECK_GE(m->alloc_tid, 0); 439 if (SANITIZER_WORDSIZE == 64) // On 32-bits this resides in user area. 440 CHECK_EQ(m->free_tid, kInvalidTid); 441 AsanThread *t = asanThreadRegistry().GetCurrent(); 442 m->free_tid = t ? t->tid() : 0; 443 if (flags()->use_stack_depot) { 444 m->free_context_id = StackDepotPut(stack->trace, stack->size); 445 } else { 446 m->free_context_id = 0; 447 StackTrace::CompressStack(stack, m->FreeStackBeg(), m->FreeStackSize()); 448 } 449 CHECK(m->chunk_state == CHUNK_QUARANTINE); 450 // Poison the region. 451 PoisonShadow(m->Beg(), 452 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY), 453 kAsanHeapFreeMagic); 454 455 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 456 thread_stats.frees++; 457 thread_stats.freed += m->UsedSize(); 458 459 // Push into quarantine. 460 if (t) { 461 AsanThreadLocalMallocStorage *ms = &t->malloc_storage(); 462 AllocatorCache *ac = GetAllocatorCache(ms); 463 quarantine.Put(GetQuarantineCache(ms), QuarantineCallback(ac), 464 m, m->UsedSize()); 465 } else { 466 SpinMutexLock l(&fallback_mutex); 467 AllocatorCache *ac = &fallback_allocator_cache; 468 quarantine.Put(&fallback_quarantine_cache, QuarantineCallback(ac), 469 m, m->UsedSize()); 470 } 471} 472 473static void *Reallocate(void *old_ptr, uptr new_size, StackTrace *stack) { 474 CHECK(old_ptr && new_size); 475 uptr p = reinterpret_cast<uptr>(old_ptr); 476 uptr chunk_beg = p - kChunkHeaderSize; 477 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 478 479 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 480 thread_stats.reallocs++; 481 thread_stats.realloced += new_size; 482 483 CHECK(m->chunk_state == CHUNK_ALLOCATED); 484 uptr old_size = m->UsedSize(); 485 uptr memcpy_size = Min(new_size, old_size); 486 void *new_ptr = Allocate(new_size, 8, stack, FROM_MALLOC); 487 if (new_ptr) { 488 CHECK(REAL(memcpy) != 0); 489 REAL(memcpy)(new_ptr, old_ptr, memcpy_size); 490 Deallocate(old_ptr, stack, FROM_MALLOC); 491 } 492 return new_ptr; 493} 494 495static AsanChunk *GetAsanChunkByAddr(uptr p) { 496 void *ptr = reinterpret_cast<void *>(p); 497 uptr alloc_beg = reinterpret_cast<uptr>(allocator.GetBlockBegin(ptr)); 498 if (!alloc_beg) return 0; 499 uptr *memalign_magic = reinterpret_cast<uptr *>(alloc_beg); 500 if (memalign_magic[0] == kMemalignMagic) { 501 AsanChunk *m = reinterpret_cast<AsanChunk *>(memalign_magic[1]); 502 CHECK(m->from_memalign); 503 return m; 504 } 505 if (!allocator.FromPrimary(ptr)) { 506 uptr *meta = reinterpret_cast<uptr *>( 507 allocator.GetMetaData(reinterpret_cast<void *>(alloc_beg))); 508 AsanChunk *m = reinterpret_cast<AsanChunk *>(meta[1]); 509 return m; 510 } 511 uptr actual_size = allocator.GetActuallyAllocatedSize(ptr); 512 CHECK_LE(actual_size, SizeClassMap::kMaxSize); 513 // We know the actually allocted size, but we don't know the redzone size. 514 // Just try all possible redzone sizes. 515 for (u32 rz_log = 0; rz_log < 8; rz_log++) { 516 u32 rz_size = RZLog2Size(rz_log); 517 uptr max_possible_size = actual_size - rz_size; 518 if (ComputeRZLog(max_possible_size) != rz_log) 519 continue; 520 return reinterpret_cast<AsanChunk *>( 521 alloc_beg + rz_size - kChunkHeaderSize); 522 } 523 return 0; 524} 525 526static uptr AllocationSize(uptr p) { 527 AsanChunk *m = GetAsanChunkByAddr(p); 528 if (!m) return 0; 529 if (m->chunk_state != CHUNK_ALLOCATED) return 0; 530 if (m->Beg() != p) return 0; 531 return m->UsedSize(); 532} 533 534// We have an address between two chunks, and we want to report just one. 535AsanChunk *ChooseChunk(uptr addr, 536 AsanChunk *left_chunk, AsanChunk *right_chunk) { 537 // Prefer an allocated chunk over freed chunk and freed chunk 538 // over available chunk. 539 if (left_chunk->chunk_state != right_chunk->chunk_state) { 540 if (left_chunk->chunk_state == CHUNK_ALLOCATED) 541 return left_chunk; 542 if (right_chunk->chunk_state == CHUNK_ALLOCATED) 543 return right_chunk; 544 if (left_chunk->chunk_state == CHUNK_QUARANTINE) 545 return left_chunk; 546 if (right_chunk->chunk_state == CHUNK_QUARANTINE) 547 return right_chunk; 548 } 549 // Same chunk_state: choose based on offset. 550 sptr l_offset = 0, r_offset = 0; 551 CHECK(AsanChunkView(left_chunk).AddrIsAtRight(addr, 1, &l_offset)); 552 CHECK(AsanChunkView(right_chunk).AddrIsAtLeft(addr, 1, &r_offset)); 553 if (l_offset < r_offset) 554 return left_chunk; 555 return right_chunk; 556} 557 558AsanChunkView FindHeapChunkByAddress(uptr addr) { 559 AsanChunk *m1 = GetAsanChunkByAddr(addr); 560 if (!m1) return AsanChunkView(m1); 561 sptr offset = 0; 562 if (AsanChunkView(m1).AddrIsAtLeft(addr, 1, &offset)) { 563 // The address is in the chunk's left redzone, so maybe it is actually 564 // a right buffer overflow from the other chunk to the left. 565 // Search a bit to the left to see if there is another chunk. 566 AsanChunk *m2 = 0; 567 for (uptr l = 1; l < GetPageSizeCached(); l++) { 568 m2 = GetAsanChunkByAddr(addr - l); 569 if (m2 == m1) continue; // Still the same chunk. 570 break; 571 } 572 if (m2 && AsanChunkView(m2).AddrIsAtRight(addr, 1, &offset)) 573 m1 = ChooseChunk(addr, m2, m1); 574 } 575 return AsanChunkView(m1); 576} 577 578void AsanThreadLocalMallocStorage::CommitBack() { 579 AllocatorCache *ac = GetAllocatorCache(this); 580 quarantine.Drain(GetQuarantineCache(this), QuarantineCallback(ac)); 581 allocator.SwallowCache(GetAllocatorCache(this)); 582} 583 584void PrintInternalAllocatorStats() { 585 allocator.PrintStats(); 586} 587 588SANITIZER_INTERFACE_ATTRIBUTE 589void *asan_memalign(uptr alignment, uptr size, StackTrace *stack, 590 AllocType alloc_type) { 591 return Allocate(size, alignment, stack, alloc_type); 592} 593 594SANITIZER_INTERFACE_ATTRIBUTE 595void asan_free(void *ptr, StackTrace *stack, AllocType alloc_type) { 596 Deallocate(ptr, stack, alloc_type); 597} 598 599SANITIZER_INTERFACE_ATTRIBUTE 600void *asan_malloc(uptr size, StackTrace *stack) { 601 return Allocate(size, 8, stack, FROM_MALLOC); 602} 603 604void *asan_calloc(uptr nmemb, uptr size, StackTrace *stack) { 605 if (CallocShouldReturnNullDueToOverflow(size, nmemb)) return 0; 606 void *ptr = Allocate(nmemb * size, 8, stack, FROM_MALLOC); 607 if (ptr) 608 REAL(memset)(ptr, 0, nmemb * size); 609 return ptr; 610} 611 612void *asan_realloc(void *p, uptr size, StackTrace *stack) { 613 if (p == 0) 614 return Allocate(size, 8, stack, FROM_MALLOC); 615 if (size == 0) { 616 Deallocate(p, stack, FROM_MALLOC); 617 return 0; 618 } 619 return Reallocate(p, size, stack); 620} 621 622void *asan_valloc(uptr size, StackTrace *stack) { 623 return Allocate(size, GetPageSizeCached(), stack, FROM_MALLOC); 624} 625 626void *asan_pvalloc(uptr size, StackTrace *stack) { 627 uptr PageSize = GetPageSizeCached(); 628 size = RoundUpTo(size, PageSize); 629 if (size == 0) { 630 // pvalloc(0) should allocate one page. 631 size = PageSize; 632 } 633 return Allocate(size, PageSize, stack, FROM_MALLOC); 634} 635 636int asan_posix_memalign(void **memptr, uptr alignment, uptr size, 637 StackTrace *stack) { 638 void *ptr = Allocate(size, alignment, stack, FROM_MALLOC); 639 CHECK(IsAligned((uptr)ptr, alignment)); 640 *memptr = ptr; 641 return 0; 642} 643 644uptr asan_malloc_usable_size(void *ptr, StackTrace *stack) { 645 CHECK(stack); 646 if (ptr == 0) return 0; 647 uptr usable_size = AllocationSize(reinterpret_cast<uptr>(ptr)); 648 if (flags()->check_malloc_usable_size && (usable_size == 0)) 649 ReportMallocUsableSizeNotOwned((uptr)ptr, stack); 650 return usable_size; 651} 652 653uptr asan_mz_size(const void *ptr) { 654 UNIMPLEMENTED(); 655 return 0; 656} 657 658void asan_mz_force_lock() { 659 UNIMPLEMENTED(); 660} 661 662void asan_mz_force_unlock() { 663 UNIMPLEMENTED(); 664} 665 666} // namespace __asan 667 668// ---------------------- Interface ---------------- {{{1 669using namespace __asan; // NOLINT 670 671// ASan allocator doesn't reserve extra bytes, so normally we would 672// just return "size". We don't want to expose our redzone sizes, etc here. 673uptr __asan_get_estimated_allocated_size(uptr size) { 674 return size; 675} 676 677bool __asan_get_ownership(const void *p) { 678 uptr ptr = reinterpret_cast<uptr>(p); 679 return (AllocationSize(ptr) > 0); 680} 681 682uptr __asan_get_allocated_size(const void *p) { 683 if (p == 0) return 0; 684 uptr ptr = reinterpret_cast<uptr>(p); 685 uptr allocated_size = AllocationSize(ptr); 686 // Die if p is not malloced or if it is already freed. 687 if (allocated_size == 0) { 688 GET_STACK_TRACE_FATAL_HERE; 689 ReportAsanGetAllocatedSizeNotOwned(ptr, &stack); 690 } 691 return allocated_size; 692} 693 694#if !SANITIZER_SUPPORTS_WEAK_HOOKS 695// Provide default (no-op) implementation of malloc hooks. 696extern "C" { 697SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE 698void __asan_malloc_hook(void *ptr, uptr size) { 699 (void)ptr; 700 (void)size; 701} 702SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE 703void __asan_free_hook(void *ptr) { 704 (void)ptr; 705} 706} // extern "C" 707#endif 708 709 710#endif // ASAN_ALLOCATOR_VERSION 711