asan_allocator2.cc revision 220ba2f6f98d44e1e8a88b4dee8ed456cf54ff33
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/asan_interface.h" 26#include "sanitizer_common/sanitizer_allocator.h" 27#include "sanitizer_common/sanitizer_internal_defs.h" 28#include "sanitizer_common/sanitizer_list.h" 29#include "sanitizer_common/sanitizer_stackdepot.h" 30#include "sanitizer_common/sanitizer_quarantine.h" 31 32namespace __asan { 33 34struct AsanMapUnmapCallback { 35 void OnMap(uptr p, uptr size) const { 36 PoisonShadow(p, size, kAsanHeapLeftRedzoneMagic); 37 // Statistics. 38 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 39 thread_stats.mmaps++; 40 thread_stats.mmaped += size; 41 } 42 void OnUnmap(uptr p, uptr size) const { 43 PoisonShadow(p, size, 0); 44 // We are about to unmap a chunk of user memory. 45 // Mark the corresponding shadow memory as not needed. 46 // Since asan's mapping is compacting, the shadow chunk may be 47 // not page-aligned, so we only flush the page-aligned portion. 48 uptr page_size = GetPageSizeCached(); 49 uptr shadow_beg = RoundUpTo(MemToShadow(p), page_size); 50 uptr shadow_end = RoundDownTo(MemToShadow(p + size), page_size); 51 FlushUnneededShadowMemory(shadow_beg, shadow_end - shadow_beg); 52 // Statistics. 53 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 54 thread_stats.munmaps++; 55 thread_stats.munmaped += size; 56 } 57}; 58 59#if SANITIZER_WORDSIZE == 64 60const uptr kAllocatorSpace = 0x600000000000ULL; 61const uptr kAllocatorSize = 0x10000000000ULL; // 1T. 62typedef DefaultSizeClassMap SizeClassMap; 63typedef SizeClassAllocator64<kAllocatorSpace, kAllocatorSize, 0 /*metadata*/, 64 SizeClassMap, AsanMapUnmapCallback> PrimaryAllocator; 65#elif SANITIZER_WORDSIZE == 32 66static const u64 kAddressSpaceSize = 1ULL << 32; 67typedef CompactSizeClassMap SizeClassMap; 68typedef SizeClassAllocator32<0, kAddressSpaceSize, 16, 69 SizeClassMap, AsanMapUnmapCallback> PrimaryAllocator; 70#endif 71 72typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache; 73typedef LargeMmapAllocator<AsanMapUnmapCallback> SecondaryAllocator; 74typedef CombinedAllocator<PrimaryAllocator, AllocatorCache, 75 SecondaryAllocator> Allocator; 76 77// We can not use THREADLOCAL because it is not supported on some of the 78// platforms we care about (OSX 10.6, Android). 79// static THREADLOCAL AllocatorCache cache; 80AllocatorCache *GetAllocatorCache(AsanThreadLocalMallocStorage *ms) { 81 CHECK(ms); 82 CHECK_LE(sizeof(AllocatorCache), sizeof(ms->allocator2_cache)); 83 return reinterpret_cast<AllocatorCache *>(ms->allocator2_cache); 84} 85 86static Allocator allocator; 87 88static const uptr kMaxAllowedMallocSize = 89 FIRST_32_SECOND_64(3UL << 30, 8UL << 30); 90 91static const uptr kMaxThreadLocalQuarantine = 92 FIRST_32_SECOND_64(1 << 18, 1 << 20); 93 94static const uptr kReturnOnZeroMalloc = 2048; // Zero page is protected. 95 96// Every chunk of memory allocated by this allocator can be in one of 3 states: 97// CHUNK_AVAILABLE: the chunk is in the free list and ready to be allocated. 98// CHUNK_ALLOCATED: the chunk is allocated and not yet freed. 99// CHUNK_QUARANTINE: the chunk was freed and put into quarantine zone. 100enum { 101 CHUNK_AVAILABLE = 0, // 0 is the default value even if we didn't set it. 102 CHUNK_ALLOCATED = 2, 103 CHUNK_QUARANTINE = 3 104}; 105 106// Valid redzone sizes are 16, 32, 64, ... 2048, so we encode them in 3 bits. 107// We use adaptive redzones: for larger allocation larger redzones are used. 108static u32 RZLog2Size(u32 rz_log) { 109 CHECK_LT(rz_log, 8); 110 return 16 << rz_log; 111} 112 113static u32 RZSize2Log(u32 rz_size) { 114 CHECK_GE(rz_size, 16); 115 CHECK_LE(rz_size, 2048); 116 CHECK(IsPowerOfTwo(rz_size)); 117 u32 res = __builtin_ctz(rz_size) - 4; 118 CHECK_EQ(rz_size, RZLog2Size(res)); 119 return res; 120} 121 122static uptr ComputeRZLog(uptr user_requested_size) { 123 u32 rz_log = 124 user_requested_size <= 64 - 16 ? 0 : 125 user_requested_size <= 128 - 32 ? 1 : 126 user_requested_size <= 512 - 64 ? 2 : 127 user_requested_size <= 4096 - 128 ? 3 : 128 user_requested_size <= (1 << 14) - 256 ? 4 : 129 user_requested_size <= (1 << 15) - 512 ? 5 : 130 user_requested_size <= (1 << 16) - 1024 ? 6 : 7; 131 return Max(rz_log, RZSize2Log(flags()->redzone)); 132} 133 134// The memory chunk allocated from the underlying allocator looks like this: 135// L L L L L L H H U U U U U U R R 136// L -- left redzone words (0 or more bytes) 137// H -- ChunkHeader (16 bytes), which is also a part of the left redzone. 138// U -- user memory. 139// R -- right redzone (0 or more bytes) 140// ChunkBase consists of ChunkHeader and other bytes that overlap with user 141// memory. 142 143// If a memory chunk is allocated by memalign and we had to increase the 144// allocation size to achieve the proper alignment, then we store this magic 145// value in the first uptr word of the memory block and store the address of 146// ChunkBase in the next uptr. 147// M B ? ? ? L L L L L L H H U U U U U U 148// M -- magic value kMemalignMagic 149// B -- address of ChunkHeader pointing to the first 'H' 150static const uptr kMemalignMagic = 0xCC6E96B9; 151 152struct ChunkHeader { 153 // 1-st 8 bytes. 154 u32 chunk_state : 8; // Must be first. 155 u32 alloc_tid : 24; 156 157 u32 free_tid : 24; 158 u32 from_memalign : 1; 159 u32 alloc_type : 2; 160 u32 rz_log : 3; 161 // 2-nd 8 bytes 162 // This field is used for small sizes. For large sizes it is equal to 163 // SizeClassMap::kMaxSize and the actual size is stored in the 164 // SecondaryAllocator's metadata. 165 u32 user_requested_size; 166 u32 alloc_context_id; 167}; 168 169struct ChunkBase : ChunkHeader { 170 // Header2, intersects with user memory. 171 AsanChunk *next; 172 u32 free_context_id; 173}; 174 175static const uptr kChunkHeaderSize = sizeof(ChunkHeader); 176static const uptr kChunkHeader2Size = sizeof(ChunkBase) - kChunkHeaderSize; 177COMPILER_CHECK(kChunkHeaderSize == 16); 178COMPILER_CHECK(kChunkHeader2Size <= 16); 179 180struct AsanChunk: ChunkBase { 181 uptr Beg() { return reinterpret_cast<uptr>(this) + kChunkHeaderSize; } 182 uptr UsedSize() { 183 if (user_requested_size != SizeClassMap::kMaxSize) 184 return user_requested_size; 185 return *reinterpret_cast<uptr *>(allocator.GetMetaData(AllocBeg())); 186 } 187 void *AllocBeg() { 188 if (from_memalign) 189 return allocator.GetBlockBegin(reinterpret_cast<void *>(this)); 190 return reinterpret_cast<void*>(Beg() - RZLog2Size(rz_log)); 191 } 192 // We store the alloc/free stack traces in the chunk itself. 193 u32 *AllocStackBeg() { 194 return (u32*)(Beg() - RZLog2Size(rz_log)); 195 } 196 uptr AllocStackSize() { 197 CHECK_LE(RZLog2Size(rz_log), kChunkHeaderSize); 198 return (RZLog2Size(rz_log) - kChunkHeaderSize) / sizeof(u32); 199 } 200 u32 *FreeStackBeg() { 201 return (u32*)(Beg() + kChunkHeader2Size); 202 } 203 uptr FreeStackSize() { 204 if (user_requested_size < kChunkHeader2Size) return 0; 205 uptr available = RoundUpTo(user_requested_size, SHADOW_GRANULARITY); 206 return (available - kChunkHeader2Size) / sizeof(u32); 207 } 208}; 209 210uptr AsanChunkView::Beg() { return chunk_->Beg(); } 211uptr AsanChunkView::End() { return Beg() + UsedSize(); } 212uptr AsanChunkView::UsedSize() { return chunk_->UsedSize(); } 213uptr AsanChunkView::AllocTid() { return chunk_->alloc_tid; } 214uptr AsanChunkView::FreeTid() { return chunk_->free_tid; } 215 216static void GetStackTraceFromId(u32 id, StackTrace *stack) { 217 CHECK(id); 218 uptr size = 0; 219 const uptr *trace = StackDepotGet(id, &size); 220 CHECK_LT(size, kStackTraceMax); 221 internal_memcpy(stack->trace, trace, sizeof(uptr) * size); 222 stack->size = size; 223} 224 225void AsanChunkView::GetAllocStack(StackTrace *stack) { 226 if (flags()->use_stack_depot) 227 GetStackTraceFromId(chunk_->alloc_context_id, stack); 228 else 229 StackTrace::UncompressStack(stack, chunk_->AllocStackBeg(), 230 chunk_->AllocStackSize()); 231} 232 233void AsanChunkView::GetFreeStack(StackTrace *stack) { 234 if (flags()->use_stack_depot) 235 GetStackTraceFromId(chunk_->free_context_id, stack); 236 else 237 StackTrace::UncompressStack(stack, chunk_->FreeStackBeg(), 238 chunk_->FreeStackSize()); 239} 240 241struct QuarantineCallback; 242typedef Quarantine<QuarantineCallback, AsanChunk> AsanQuarantine; 243typedef AsanQuarantine::Cache QuarantineCache; 244static AsanQuarantine quarantine(LINKER_INITIALIZED); 245static QuarantineCache fallback_quarantine_cache(LINKER_INITIALIZED); 246static AllocatorCache fallback_allocator_cache; 247static SpinMutex fallback_mutex; 248 249QuarantineCache *GetQuarantineCache(AsanThreadLocalMallocStorage *ms) { 250 CHECK(ms); 251 CHECK_LE(sizeof(QuarantineCache), sizeof(ms->quarantine_cache)); 252 return reinterpret_cast<QuarantineCache *>(ms->quarantine_cache); 253} 254 255struct QuarantineCallback { 256 explicit QuarantineCallback(AllocatorCache *cache) 257 : cache_(cache) { 258 } 259 260 void Recycle(AsanChunk *m) { 261 CHECK(m->chunk_state == CHUNK_QUARANTINE); 262 m->chunk_state = CHUNK_AVAILABLE; 263 CHECK_NE(m->alloc_tid, kInvalidTid); 264 CHECK_NE(m->free_tid, kInvalidTid); 265 PoisonShadow(m->Beg(), 266 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY), 267 kAsanHeapLeftRedzoneMagic); 268 void *p = reinterpret_cast<void *>(m->AllocBeg()); 269 if (m->from_memalign) { 270 uptr *memalign_magic = reinterpret_cast<uptr *>(p); 271 CHECK_EQ(memalign_magic[0], kMemalignMagic); 272 CHECK_EQ(memalign_magic[1], reinterpret_cast<uptr>(m)); 273 } 274 275 // Statistics. 276 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 277 thread_stats.real_frees++; 278 thread_stats.really_freed += m->UsedSize(); 279 280 allocator.Deallocate(cache_, p); 281 } 282 283 void *Allocate(uptr size) { 284 return allocator.Allocate(cache_, size, 1, false); 285 } 286 287 void Deallocate(void *p) { 288 allocator.Deallocate(cache_, p); 289 } 290 291 AllocatorCache *cache_; 292}; 293 294static void Init() { 295 static int inited = 0; 296 if (inited) return; 297 __asan_init(); 298 inited = true; // this must happen before any threads are created. 299 allocator.Init(); 300 quarantine.Init((uptr)flags()->quarantine_size, kMaxThreadLocalQuarantine); 301} 302 303static void *Allocate(uptr size, uptr alignment, StackTrace *stack, 304 AllocType alloc_type) { 305 Init(); 306 CHECK(stack); 307 const uptr min_alignment = SHADOW_GRANULARITY; 308 if (alignment < min_alignment) 309 alignment = min_alignment; 310 if (size == 0) { 311 if (alignment <= kReturnOnZeroMalloc) 312 return reinterpret_cast<void *>(kReturnOnZeroMalloc); 313 else 314 return 0; // 0 bytes with large alignment requested. Just return 0. 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 || p == kReturnOnZeroMalloc) return; 421 uptr chunk_beg = p - kChunkHeaderSize; 422 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 423 424 // Flip the chunk_state atomically to avoid race on double-free. 425 u8 old_chunk_state = atomic_exchange((atomic_uint8_t*)m, CHUNK_QUARANTINE, 426 memory_order_relaxed); 427 428 if (old_chunk_state == CHUNK_QUARANTINE) 429 ReportDoubleFree((uptr)ptr, stack); 430 else if (old_chunk_state != CHUNK_ALLOCATED) 431 ReportFreeNotMalloced((uptr)ptr, stack); 432 CHECK(old_chunk_state == CHUNK_ALLOCATED); 433 if (m->alloc_type != alloc_type && flags()->alloc_dealloc_mismatch) 434 ReportAllocTypeMismatch((uptr)ptr, stack, 435 (AllocType)m->alloc_type, (AllocType)alloc_type); 436 437 CHECK_GE(m->alloc_tid, 0); 438 if (SANITIZER_WORDSIZE == 64) // On 32-bits this resides in user area. 439 CHECK_EQ(m->free_tid, kInvalidTid); 440 AsanThread *t = asanThreadRegistry().GetCurrent(); 441 m->free_tid = t ? t->tid() : 0; 442 if (flags()->use_stack_depot) { 443 m->free_context_id = StackDepotPut(stack->trace, stack->size); 444 } else { 445 m->free_context_id = 0; 446 StackTrace::CompressStack(stack, m->FreeStackBeg(), m->FreeStackSize()); 447 } 448 CHECK(m->chunk_state == CHUNK_QUARANTINE); 449 // Poison the region. 450 PoisonShadow(m->Beg(), 451 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY), 452 kAsanHeapFreeMagic); 453 454 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 455 thread_stats.frees++; 456 thread_stats.freed += m->UsedSize(); 457 458 // Push into quarantine. 459 if (t) { 460 AsanThreadLocalMallocStorage *ms = &t->malloc_storage(); 461 AllocatorCache *ac = GetAllocatorCache(ms); 462 quarantine.Put(GetQuarantineCache(ms), QuarantineCallback(ac), 463 m, m->UsedSize()); 464 } else { 465 SpinMutexLock l(&fallback_mutex); 466 AllocatorCache *ac = &fallback_allocator_cache; 467 quarantine.Put(&fallback_quarantine_cache, QuarantineCallback(ac), 468 m, m->UsedSize()); 469 } 470 471 ASAN_FREE_HOOK(ptr); 472} 473 474static void *Reallocate(void *old_ptr, uptr new_size, StackTrace *stack) { 475 CHECK(old_ptr && new_size); 476 uptr p = reinterpret_cast<uptr>(old_ptr); 477 uptr chunk_beg = p - kChunkHeaderSize; 478 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 479 480 AsanStats &thread_stats = asanThreadRegistry().GetCurrentThreadStats(); 481 thread_stats.reallocs++; 482 thread_stats.realloced += new_size; 483 484 CHECK(m->chunk_state == CHUNK_ALLOCATED); 485 uptr old_size = m->UsedSize(); 486 uptr memcpy_size = Min(new_size, old_size); 487 void *new_ptr = Allocate(new_size, 8, stack, FROM_MALLOC); 488 if (new_ptr) { 489 CHECK(REAL(memcpy) != 0); 490 REAL(memcpy)(new_ptr, old_ptr, memcpy_size); 491 Deallocate(old_ptr, stack, FROM_MALLOC); 492 } 493 return new_ptr; 494} 495 496static AsanChunk *GetAsanChunkByAddr(uptr p) { 497 void *ptr = reinterpret_cast<void *>(p); 498 uptr alloc_beg = reinterpret_cast<uptr>(allocator.GetBlockBegin(ptr)); 499 if (!alloc_beg) return 0; 500 uptr *memalign_magic = reinterpret_cast<uptr *>(alloc_beg); 501 if (memalign_magic[0] == kMemalignMagic) { 502 AsanChunk *m = reinterpret_cast<AsanChunk *>(memalign_magic[1]); 503 CHECK(m->from_memalign); 504 return m; 505 } 506 if (!allocator.FromPrimary(ptr)) { 507 uptr *meta = reinterpret_cast<uptr *>( 508 allocator.GetMetaData(reinterpret_cast<void *>(alloc_beg))); 509 AsanChunk *m = reinterpret_cast<AsanChunk *>(meta[1]); 510 return m; 511 } 512 uptr actual_size = allocator.GetActuallyAllocatedSize(ptr); 513 CHECK_LE(actual_size, SizeClassMap::kMaxSize); 514 // We know the actually allocted size, but we don't know the redzone size. 515 // Just try all possible redzone sizes. 516 for (u32 rz_log = 0; rz_log < 8; rz_log++) { 517 u32 rz_size = RZLog2Size(rz_log); 518 uptr max_possible_size = actual_size - rz_size; 519 if (ComputeRZLog(max_possible_size) != rz_log) 520 continue; 521 return reinterpret_cast<AsanChunk *>( 522 alloc_beg + rz_size - kChunkHeaderSize); 523 } 524 return 0; 525} 526 527static uptr AllocationSize(uptr p) { 528 AsanChunk *m = GetAsanChunkByAddr(p); 529 if (!m) return 0; 530 if (m->chunk_state != CHUNK_ALLOCATED) return 0; 531 if (m->Beg() != p) return 0; 532 return m->UsedSize(); 533} 534 535// We have an address between two chunks, and we want to report just one. 536AsanChunk *ChooseChunk(uptr addr, 537 AsanChunk *left_chunk, AsanChunk *right_chunk) { 538 // Prefer an allocated chunk over freed chunk and freed chunk 539 // over available chunk. 540 if (left_chunk->chunk_state != right_chunk->chunk_state) { 541 if (left_chunk->chunk_state == CHUNK_ALLOCATED) 542 return left_chunk; 543 if (right_chunk->chunk_state == CHUNK_ALLOCATED) 544 return right_chunk; 545 if (left_chunk->chunk_state == CHUNK_QUARANTINE) 546 return left_chunk; 547 if (right_chunk->chunk_state == CHUNK_QUARANTINE) 548 return right_chunk; 549 } 550 // Same chunk_state: choose based on offset. 551 uptr l_offset = 0, r_offset = 0; 552 CHECK(AsanChunkView(left_chunk).AddrIsAtRight(addr, 1, &l_offset)); 553 CHECK(AsanChunkView(right_chunk).AddrIsAtLeft(addr, 1, &r_offset)); 554 if (l_offset < r_offset) 555 return left_chunk; 556 return right_chunk; 557} 558 559AsanChunkView FindHeapChunkByAddress(uptr addr) { 560 AsanChunk *m1 = GetAsanChunkByAddr(addr); 561 if (!m1) return AsanChunkView(m1); 562 uptr offset = 0; 563 if (AsanChunkView(m1).AddrIsAtLeft(addr, 1, &offset)) { 564 // The address is in the chunk's left redzone, so maybe it is actually 565 // a right buffer overflow from the other chunk to the left. 566 // Search a bit to the left to see if there is another chunk. 567 AsanChunk *m2 = 0; 568 for (uptr l = 1; l < GetPageSizeCached(); l++) { 569 m2 = GetAsanChunkByAddr(addr - l); 570 if (m2 == m1) continue; // Still the same chunk. 571 break; 572 } 573 if (m2 && AsanChunkView(m2).AddrIsAtRight(addr, 1, &offset)) 574 m1 = ChooseChunk(addr, m2, m1); 575 } 576 return AsanChunkView(m1); 577} 578 579void AsanThreadLocalMallocStorage::CommitBack() { 580 AllocatorCache *ac = GetAllocatorCache(this); 581 quarantine.Drain(GetQuarantineCache(this), QuarantineCallback(ac)); 582 allocator.SwallowCache(GetAllocatorCache(this)); 583} 584 585void PrintInternalAllocatorStats() { 586 allocator.PrintStats(); 587} 588 589SANITIZER_INTERFACE_ATTRIBUTE 590void *asan_memalign(uptr alignment, uptr size, StackTrace *stack, 591 AllocType alloc_type) { 592 return Allocate(size, alignment, stack, alloc_type); 593} 594 595SANITIZER_INTERFACE_ATTRIBUTE 596void asan_free(void *ptr, StackTrace *stack, AllocType alloc_type) { 597 Deallocate(ptr, stack, alloc_type); 598} 599 600SANITIZER_INTERFACE_ATTRIBUTE 601void *asan_malloc(uptr size, StackTrace *stack) { 602 return Allocate(size, 8, stack, FROM_MALLOC); 603} 604 605void *asan_calloc(uptr nmemb, uptr size, StackTrace *stack) { 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 (ptr == kReturnOnZeroMalloc) || (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 && ptr != kReturnOnZeroMalloc) { 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