asan_allocator2.cc revision 5d43b5a695ca6b6dc4eff05e723a7f39643f3266
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//===----------------------------------------------------------------------===// 17#include "asan_allocator.h" 18 19#include "asan_mapping.h" 20#include "asan_poisoning.h" 21#include "asan_report.h" 22#include "asan_thread.h" 23#include "sanitizer_common/sanitizer_allocator.h" 24#include "sanitizer_common/sanitizer_flags.h" 25#include "sanitizer_common/sanitizer_internal_defs.h" 26#include "sanitizer_common/sanitizer_list.h" 27#include "sanitizer_common/sanitizer_stackdepot.h" 28#include "sanitizer_common/sanitizer_quarantine.h" 29#include "lsan/lsan_common.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 = 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 = 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; 61const uptr kAllocatorSize = 0x20000000000ULL; // 2T. 62#else 63const uptr kAllocatorSpace = 0x600000000000ULL; 64const uptr kAllocatorSize = 0x40000000000ULL; // 4T. 65#endif 66typedef DefaultSizeClassMap SizeClassMap; 67typedef SizeClassAllocator64<kAllocatorSpace, kAllocatorSize, 0 /*metadata*/, 68 SizeClassMap, AsanMapUnmapCallback> PrimaryAllocator; 69#elif SANITIZER_WORDSIZE == 32 70static const u64 kAddressSpaceSize = 1ULL << 32; 71typedef CompactSizeClassMap SizeClassMap; 72static const uptr kRegionSizeLog = 20; 73static const uptr kFlatByteMapSize = kAddressSpaceSize >> kRegionSizeLog; 74typedef SizeClassAllocator32<0, kAddressSpaceSize, 16, 75 SizeClassMap, kRegionSizeLog, 76 FlatByteMap<kFlatByteMapSize>, 77 AsanMapUnmapCallback> PrimaryAllocator; 78#endif 79 80typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache; 81typedef LargeMmapAllocator<AsanMapUnmapCallback> SecondaryAllocator; 82typedef CombinedAllocator<PrimaryAllocator, AllocatorCache, 83 SecondaryAllocator> Allocator; 84 85// We can not use THREADLOCAL because it is not supported on some of the 86// platforms we care about (OSX 10.6, Android). 87// static THREADLOCAL AllocatorCache cache; 88AllocatorCache *GetAllocatorCache(AsanThreadLocalMallocStorage *ms) { 89 CHECK(ms); 90 CHECK_LE(sizeof(AllocatorCache), sizeof(ms->allocator2_cache)); 91 return reinterpret_cast<AllocatorCache *>(ms->allocator2_cache); 92} 93 94static Allocator allocator; 95 96static const uptr kMaxAllowedMallocSize = 97 FIRST_32_SECOND_64(3UL << 30, 8UL << 30); 98 99static const uptr kMaxThreadLocalQuarantine = 100 FIRST_32_SECOND_64(1 << 18, 1 << 20); 101 102// Every chunk of memory allocated by this allocator can be in one of 3 states: 103// CHUNK_AVAILABLE: the chunk is in the free list and ready to be allocated. 104// CHUNK_ALLOCATED: the chunk is allocated and not yet freed. 105// CHUNK_QUARANTINE: the chunk was freed and put into quarantine zone. 106enum { 107 CHUNK_AVAILABLE = 0, // 0 is the default value even if we didn't set it. 108 CHUNK_ALLOCATED = 2, 109 CHUNK_QUARANTINE = 3 110}; 111 112// Valid redzone sizes are 16, 32, 64, ... 2048, so we encode them in 3 bits. 113// We use adaptive redzones: for larger allocation larger redzones are used. 114static u32 RZLog2Size(u32 rz_log) { 115 CHECK_LT(rz_log, 8); 116 return 16 << rz_log; 117} 118 119static u32 RZSize2Log(u32 rz_size) { 120 CHECK_GE(rz_size, 16); 121 CHECK_LE(rz_size, 2048); 122 CHECK(IsPowerOfTwo(rz_size)); 123 u32 res = Log2(rz_size) - 4; 124 CHECK_EQ(rz_size, RZLog2Size(res)); 125 return res; 126} 127 128static uptr ComputeRZLog(uptr user_requested_size) { 129 u32 rz_log = 130 user_requested_size <= 64 - 16 ? 0 : 131 user_requested_size <= 128 - 32 ? 1 : 132 user_requested_size <= 512 - 64 ? 2 : 133 user_requested_size <= 4096 - 128 ? 3 : 134 user_requested_size <= (1 << 14) - 256 ? 4 : 135 user_requested_size <= (1 << 15) - 512 ? 5 : 136 user_requested_size <= (1 << 16) - 1024 ? 6 : 7; 137 return Max(rz_log, RZSize2Log(flags()->redzone)); 138} 139 140// The memory chunk allocated from the underlying allocator looks like this: 141// L L L L L L H H U U U U U U R R 142// L -- left redzone words (0 or more bytes) 143// H -- ChunkHeader (16 bytes), which is also a part of the left redzone. 144// U -- user memory. 145// R -- right redzone (0 or more bytes) 146// ChunkBase consists of ChunkHeader and other bytes that overlap with user 147// memory. 148 149// If the left redzone is greater than the ChunkHeader size we store a magic 150// value in the first uptr word of the memory block and store the address of 151// ChunkBase in the next uptr. 152// M B L L L L L L L L L H H U U U U U U 153// | ^ 154// ---------------------| 155// M -- magic value kAllocBegMagic 156// B -- address of ChunkHeader pointing to the first 'H' 157static const uptr kAllocBegMagic = 0xCC6E96B9; 158 159struct ChunkHeader { 160 // 1-st 8 bytes. 161 u32 chunk_state : 8; // Must be first. 162 u32 alloc_tid : 24; 163 164 u32 free_tid : 24; 165 u32 from_memalign : 1; 166 u32 alloc_type : 2; 167 u32 rz_log : 3; 168 u32 lsan_tag : 2; 169 // 2-nd 8 bytes 170 // This field is used for small sizes. For large sizes it is equal to 171 // SizeClassMap::kMaxSize and the actual size is stored in the 172 // SecondaryAllocator's metadata. 173 u32 user_requested_size; 174 u32 alloc_context_id; 175}; 176 177struct ChunkBase : ChunkHeader { 178 // Header2, intersects with user memory. 179 u32 free_context_id; 180}; 181 182static const uptr kChunkHeaderSize = sizeof(ChunkHeader); 183static const uptr kChunkHeader2Size = sizeof(ChunkBase) - kChunkHeaderSize; 184COMPILER_CHECK(kChunkHeaderSize == 16); 185COMPILER_CHECK(kChunkHeader2Size <= 16); 186 187struct AsanChunk: ChunkBase { 188 uptr Beg() { return reinterpret_cast<uptr>(this) + kChunkHeaderSize; } 189 uptr UsedSize() { 190 if (user_requested_size != SizeClassMap::kMaxSize) 191 return user_requested_size; 192 return *reinterpret_cast<uptr *>(allocator.GetMetaData(AllocBeg())); 193 } 194 void *AllocBeg() { 195 if (from_memalign) 196 return allocator.GetBlockBegin(reinterpret_cast<void *>(this)); 197 return reinterpret_cast<void*>(Beg() - RZLog2Size(rz_log)); 198 } 199 // If we don't use stack depot, we store the alloc/free stack traces 200 // in the chunk itself. 201 u32 *AllocStackBeg() { 202 return (u32*)(Beg() - RZLog2Size(rz_log)); 203 } 204 uptr AllocStackSize() { 205 CHECK_LE(RZLog2Size(rz_log), kChunkHeaderSize); 206 return (RZLog2Size(rz_log) - kChunkHeaderSize) / sizeof(u32); 207 } 208 u32 *FreeStackBeg() { 209 return (u32*)(Beg() + kChunkHeader2Size); 210 } 211 uptr FreeStackSize() { 212 if (user_requested_size < kChunkHeader2Size) return 0; 213 uptr available = RoundUpTo(user_requested_size, SHADOW_GRANULARITY); 214 return (available - kChunkHeader2Size) / sizeof(u32); 215 } 216 bool AddrIsInside(uptr addr) { 217 return (addr >= Beg()) && (addr < Beg() + UsedSize()); 218 } 219}; 220 221uptr AsanChunkView::Beg() { return chunk_->Beg(); } 222uptr AsanChunkView::End() { return Beg() + UsedSize(); } 223uptr AsanChunkView::UsedSize() { return chunk_->UsedSize(); } 224uptr AsanChunkView::AllocTid() { return chunk_->alloc_tid; } 225uptr AsanChunkView::FreeTid() { return chunk_->free_tid; } 226 227static void GetStackTraceFromId(u32 id, StackTrace *stack) { 228 CHECK(id); 229 uptr size = 0; 230 const uptr *trace = StackDepotGet(id, &size); 231 CHECK_LT(size, kStackTraceMax); 232 internal_memcpy(stack->trace, trace, sizeof(uptr) * size); 233 stack->size = size; 234} 235 236void AsanChunkView::GetAllocStack(StackTrace *stack) { 237 if (flags()->use_stack_depot) 238 GetStackTraceFromId(chunk_->alloc_context_id, stack); 239 else 240 StackTrace::UncompressStack(stack, chunk_->AllocStackBeg(), 241 chunk_->AllocStackSize()); 242} 243 244void AsanChunkView::GetFreeStack(StackTrace *stack) { 245 if (flags()->use_stack_depot) 246 GetStackTraceFromId(chunk_->free_context_id, stack); 247 else 248 StackTrace::UncompressStack(stack, chunk_->FreeStackBeg(), 249 chunk_->FreeStackSize()); 250} 251 252struct QuarantineCallback; 253typedef Quarantine<QuarantineCallback, AsanChunk> AsanQuarantine; 254typedef AsanQuarantine::Cache QuarantineCache; 255static AsanQuarantine quarantine(LINKER_INITIALIZED); 256static QuarantineCache fallback_quarantine_cache(LINKER_INITIALIZED); 257static AllocatorCache fallback_allocator_cache; 258static SpinMutex fallback_mutex; 259 260QuarantineCache *GetQuarantineCache(AsanThreadLocalMallocStorage *ms) { 261 CHECK(ms); 262 CHECK_LE(sizeof(QuarantineCache), sizeof(ms->quarantine_cache)); 263 return reinterpret_cast<QuarantineCache *>(ms->quarantine_cache); 264} 265 266struct QuarantineCallback { 267 explicit QuarantineCallback(AllocatorCache *cache) 268 : cache_(cache) { 269 } 270 271 void Recycle(AsanChunk *m) { 272 CHECK_EQ(m->chunk_state, CHUNK_QUARANTINE); 273 atomic_store((atomic_uint8_t*)m, CHUNK_AVAILABLE, memory_order_relaxed); 274 CHECK_NE(m->alloc_tid, kInvalidTid); 275 CHECK_NE(m->free_tid, kInvalidTid); 276 PoisonShadow(m->Beg(), 277 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY), 278 kAsanHeapLeftRedzoneMagic); 279 void *p = reinterpret_cast<void *>(m->AllocBeg()); 280 if (p != m) { 281 uptr *alloc_magic = reinterpret_cast<uptr *>(p); 282 CHECK_EQ(alloc_magic[0], kAllocBegMagic); 283 CHECK_EQ(alloc_magic[1], reinterpret_cast<uptr>(m)); 284 } 285 286 // Statistics. 287 AsanStats &thread_stats = GetCurrentThreadStats(); 288 thread_stats.real_frees++; 289 thread_stats.really_freed += m->UsedSize(); 290 291 allocator.Deallocate(cache_, p); 292 } 293 294 void *Allocate(uptr size) { 295 return allocator.Allocate(cache_, size, 1, false); 296 } 297 298 void Deallocate(void *p) { 299 allocator.Deallocate(cache_, p); 300 } 301 302 AllocatorCache *cache_; 303}; 304 305void InitializeAllocator() { 306 allocator.Init(); 307 quarantine.Init((uptr)flags()->quarantine_size, kMaxThreadLocalQuarantine); 308} 309 310static void *Allocate(uptr size, uptr alignment, StackTrace *stack, 311 AllocType alloc_type, bool can_fill) { 312 if (!asan_inited) 313 __asan_init(); 314 Flags &fl = *flags(); 315 CHECK(stack); 316 const uptr min_alignment = SHADOW_GRANULARITY; 317 if (alignment < min_alignment) 318 alignment = min_alignment; 319 if (size == 0) { 320 // We'd be happy to avoid allocating memory for zero-size requests, but 321 // some programs/tests depend on this behavior and assume that malloc would 322 // not return NULL even for zero-size allocations. Moreover, it looks like 323 // operator new should never return NULL, and results of consecutive "new" 324 // calls must be different even if the allocated size is zero. 325 size = 1; 326 } 327 CHECK(IsPowerOfTwo(alignment)); 328 uptr rz_log = ComputeRZLog(size); 329 uptr rz_size = RZLog2Size(rz_log); 330 uptr rounded_size = RoundUpTo(Max(size, kChunkHeader2Size), alignment); 331 uptr needed_size = rounded_size + rz_size; 332 if (alignment > min_alignment) 333 needed_size += alignment; 334 bool using_primary_allocator = true; 335 // If we are allocating from the secondary allocator, there will be no 336 // automatic right redzone, so add the right redzone manually. 337 if (!PrimaryAllocator::CanAllocate(needed_size, alignment)) { 338 needed_size += rz_size; 339 using_primary_allocator = false; 340 } 341 CHECK(IsAligned(needed_size, min_alignment)); 342 if (size > kMaxAllowedMallocSize || needed_size > kMaxAllowedMallocSize) { 343 Report("WARNING: AddressSanitizer failed to allocate %p bytes\n", 344 (void*)size); 345 return 0; 346 } 347 348 AsanThread *t = GetCurrentThread(); 349 void *allocated; 350 if (t) { 351 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage()); 352 allocated = allocator.Allocate(cache, needed_size, 8, false); 353 } else { 354 SpinMutexLock l(&fallback_mutex); 355 AllocatorCache *cache = &fallback_allocator_cache; 356 allocated = allocator.Allocate(cache, needed_size, 8, false); 357 } 358 uptr alloc_beg = reinterpret_cast<uptr>(allocated); 359 uptr alloc_end = alloc_beg + needed_size; 360 uptr beg_plus_redzone = alloc_beg + rz_size; 361 uptr user_beg = beg_plus_redzone; 362 if (!IsAligned(user_beg, alignment)) 363 user_beg = RoundUpTo(user_beg, alignment); 364 uptr user_end = user_beg + size; 365 CHECK_LE(user_end, alloc_end); 366 uptr chunk_beg = user_beg - kChunkHeaderSize; 367 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 368 m->alloc_type = alloc_type; 369 m->rz_log = rz_log; 370 u32 alloc_tid = t ? t->tid() : 0; 371 m->alloc_tid = alloc_tid; 372 CHECK_EQ(alloc_tid, m->alloc_tid); // Does alloc_tid fit into the bitfield? 373 m->free_tid = kInvalidTid; 374 m->from_memalign = user_beg != beg_plus_redzone; 375 if (alloc_beg != chunk_beg) { 376 CHECK_LE(alloc_beg+ 2 * sizeof(uptr), chunk_beg); 377 reinterpret_cast<uptr *>(alloc_beg)[0] = kAllocBegMagic; 378 reinterpret_cast<uptr *>(alloc_beg)[1] = chunk_beg; 379 } 380 if (using_primary_allocator) { 381 CHECK(size); 382 m->user_requested_size = size; 383 CHECK(allocator.FromPrimary(allocated)); 384 } else { 385 CHECK(!allocator.FromPrimary(allocated)); 386 m->user_requested_size = SizeClassMap::kMaxSize; 387 uptr *meta = reinterpret_cast<uptr *>(allocator.GetMetaData(allocated)); 388 meta[0] = size; 389 meta[1] = chunk_beg; 390 } 391 392 if (fl.use_stack_depot) { 393 m->alloc_context_id = StackDepotPut(stack->trace, stack->size); 394 } else { 395 m->alloc_context_id = 0; 396 StackTrace::CompressStack(stack, m->AllocStackBeg(), m->AllocStackSize()); 397 } 398 399 uptr size_rounded_down_to_granularity = RoundDownTo(size, SHADOW_GRANULARITY); 400 // Unpoison the bulk of the memory region. 401 if (size_rounded_down_to_granularity) 402 PoisonShadow(user_beg, size_rounded_down_to_granularity, 0); 403 // Deal with the end of the region if size is not aligned to granularity. 404 if (size != size_rounded_down_to_granularity && fl.poison_heap) { 405 u8 *shadow = (u8*)MemToShadow(user_beg + size_rounded_down_to_granularity); 406 *shadow = size & (SHADOW_GRANULARITY - 1); 407 } 408 409 AsanStats &thread_stats = GetCurrentThreadStats(); 410 thread_stats.mallocs++; 411 thread_stats.malloced += size; 412 thread_stats.malloced_redzones += needed_size - size; 413 uptr class_id = Min(kNumberOfSizeClasses, SizeClassMap::ClassID(needed_size)); 414 thread_stats.malloced_by_size[class_id]++; 415 if (needed_size > SizeClassMap::kMaxSize) 416 thread_stats.malloc_large++; 417 418 void *res = reinterpret_cast<void *>(user_beg); 419 if (can_fill && fl.max_malloc_fill_size) { 420 uptr fill_size = Min(size, (uptr)fl.max_malloc_fill_size); 421 REAL(memset)(res, fl.malloc_fill_byte, fill_size); 422 } 423 if (t && t->lsan_disabled()) 424 m->lsan_tag = __lsan::kSuppressed; 425 else 426 m->lsan_tag = __lsan::kDirectlyLeaked; 427 // Must be the last mutation of metadata in this function. 428 atomic_store((atomic_uint8_t *)m, CHUNK_ALLOCATED, memory_order_release); 429 ASAN_MALLOC_HOOK(res, size); 430 return res; 431} 432 433static void ReportInvalidFree(void *ptr, u8 chunk_state, StackTrace *stack) { 434 if (chunk_state == CHUNK_QUARANTINE) 435 ReportDoubleFree((uptr)ptr, stack); 436 else 437 ReportFreeNotMalloced((uptr)ptr, stack); 438} 439 440static void AtomicallySetQuarantineFlag(AsanChunk *m, 441 void *ptr, StackTrace *stack) { 442 u8 old_chunk_state = CHUNK_ALLOCATED; 443 // Flip the chunk_state atomically to avoid race on double-free. 444 if (!atomic_compare_exchange_strong((atomic_uint8_t*)m, &old_chunk_state, 445 CHUNK_QUARANTINE, memory_order_acquire)) 446 ReportInvalidFree(ptr, old_chunk_state, stack); 447 CHECK_EQ(CHUNK_ALLOCATED, old_chunk_state); 448} 449 450// Expects the chunk to already be marked as quarantined by using 451// AtomicallySetQuarantineFlag. 452static void QuarantineChunk(AsanChunk *m, void *ptr, 453 StackTrace *stack, AllocType alloc_type) { 454 CHECK_EQ(m->chunk_state, CHUNK_QUARANTINE); 455 456 if (m->alloc_type != alloc_type && flags()->alloc_dealloc_mismatch) 457 ReportAllocTypeMismatch((uptr)ptr, stack, 458 (AllocType)m->alloc_type, (AllocType)alloc_type); 459 460 CHECK_GE(m->alloc_tid, 0); 461 if (SANITIZER_WORDSIZE == 64) // On 32-bits this resides in user area. 462 CHECK_EQ(m->free_tid, kInvalidTid); 463 AsanThread *t = GetCurrentThread(); 464 m->free_tid = t ? t->tid() : 0; 465 if (flags()->use_stack_depot) { 466 m->free_context_id = StackDepotPut(stack->trace, stack->size); 467 } else { 468 m->free_context_id = 0; 469 StackTrace::CompressStack(stack, m->FreeStackBeg(), m->FreeStackSize()); 470 } 471 // Poison the region. 472 PoisonShadow(m->Beg(), 473 RoundUpTo(m->UsedSize(), SHADOW_GRANULARITY), 474 kAsanHeapFreeMagic); 475 476 AsanStats &thread_stats = GetCurrentThreadStats(); 477 thread_stats.frees++; 478 thread_stats.freed += m->UsedSize(); 479 480 // Push into quarantine. 481 if (t) { 482 AsanThreadLocalMallocStorage *ms = &t->malloc_storage(); 483 AllocatorCache *ac = GetAllocatorCache(ms); 484 quarantine.Put(GetQuarantineCache(ms), QuarantineCallback(ac), 485 m, m->UsedSize()); 486 } else { 487 SpinMutexLock l(&fallback_mutex); 488 AllocatorCache *ac = &fallback_allocator_cache; 489 quarantine.Put(&fallback_quarantine_cache, QuarantineCallback(ac), 490 m, m->UsedSize()); 491 } 492} 493 494static void Deallocate(void *ptr, StackTrace *stack, AllocType alloc_type) { 495 uptr p = reinterpret_cast<uptr>(ptr); 496 if (p == 0) return; 497 498 uptr chunk_beg = p - kChunkHeaderSize; 499 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 500 ASAN_FREE_HOOK(ptr); 501 // Must mark the chunk as quarantined before any changes to its metadata. 502 AtomicallySetQuarantineFlag(m, ptr, stack); 503 QuarantineChunk(m, ptr, stack, alloc_type); 504} 505 506static void *Reallocate(void *old_ptr, uptr new_size, StackTrace *stack) { 507 CHECK(old_ptr && new_size); 508 uptr p = reinterpret_cast<uptr>(old_ptr); 509 uptr chunk_beg = p - kChunkHeaderSize; 510 AsanChunk *m = reinterpret_cast<AsanChunk *>(chunk_beg); 511 512 AsanStats &thread_stats = GetCurrentThreadStats(); 513 thread_stats.reallocs++; 514 thread_stats.realloced += new_size; 515 516 void *new_ptr = Allocate(new_size, 8, stack, FROM_MALLOC, true); 517 if (new_ptr) { 518 u8 chunk_state = m->chunk_state; 519 if (chunk_state != CHUNK_ALLOCATED) 520 ReportInvalidFree(old_ptr, chunk_state, stack); 521 CHECK_NE(REAL(memcpy), (void*)0); 522 uptr memcpy_size = Min(new_size, m->UsedSize()); 523 // If realloc() races with free(), we may start copying freed memory. 524 // However, we will report racy double-free later anyway. 525 REAL(memcpy)(new_ptr, old_ptr, memcpy_size); 526 Deallocate(old_ptr, stack, FROM_MALLOC); 527 } 528 return new_ptr; 529} 530 531// Assumes alloc_beg == allocator.GetBlockBegin(alloc_beg). 532static AsanChunk *GetAsanChunk(void *alloc_beg) { 533 if (!alloc_beg) return 0; 534 if (!allocator.FromPrimary(alloc_beg)) { 535 uptr *meta = reinterpret_cast<uptr *>(allocator.GetMetaData(alloc_beg)); 536 AsanChunk *m = reinterpret_cast<AsanChunk *>(meta[1]); 537 return m; 538 } 539 uptr *alloc_magic = reinterpret_cast<uptr *>(alloc_beg); 540 if (alloc_magic[0] == kAllocBegMagic) 541 return reinterpret_cast<AsanChunk *>(alloc_magic[1]); 542 return reinterpret_cast<AsanChunk *>(alloc_beg); 543} 544 545static AsanChunk *GetAsanChunkByAddr(uptr p) { 546 void *alloc_beg = allocator.GetBlockBegin(reinterpret_cast<void *>(p)); 547 return GetAsanChunk(alloc_beg); 548} 549 550// Allocator must be locked when this function is called. 551static AsanChunk *GetAsanChunkByAddrFastLocked(uptr p) { 552 void *alloc_beg = 553 allocator.GetBlockBeginFastLocked(reinterpret_cast<void *>(p)); 554 return GetAsanChunk(alloc_beg); 555} 556 557static uptr AllocationSize(uptr p) { 558 AsanChunk *m = GetAsanChunkByAddr(p); 559 if (!m) return 0; 560 if (m->chunk_state != CHUNK_ALLOCATED) return 0; 561 if (m->Beg() != p) return 0; 562 return m->UsedSize(); 563} 564 565// We have an address between two chunks, and we want to report just one. 566AsanChunk *ChooseChunk(uptr addr, 567 AsanChunk *left_chunk, AsanChunk *right_chunk) { 568 // Prefer an allocated chunk over freed chunk and freed chunk 569 // over available chunk. 570 if (left_chunk->chunk_state != right_chunk->chunk_state) { 571 if (left_chunk->chunk_state == CHUNK_ALLOCATED) 572 return left_chunk; 573 if (right_chunk->chunk_state == CHUNK_ALLOCATED) 574 return right_chunk; 575 if (left_chunk->chunk_state == CHUNK_QUARANTINE) 576 return left_chunk; 577 if (right_chunk->chunk_state == CHUNK_QUARANTINE) 578 return right_chunk; 579 } 580 // Same chunk_state: choose based on offset. 581 sptr l_offset = 0, r_offset = 0; 582 CHECK(AsanChunkView(left_chunk).AddrIsAtRight(addr, 1, &l_offset)); 583 CHECK(AsanChunkView(right_chunk).AddrIsAtLeft(addr, 1, &r_offset)); 584 if (l_offset < r_offset) 585 return left_chunk; 586 return right_chunk; 587} 588 589AsanChunkView FindHeapChunkByAddress(uptr addr) { 590 AsanChunk *m1 = GetAsanChunkByAddr(addr); 591 if (!m1) return AsanChunkView(m1); 592 sptr offset = 0; 593 if (AsanChunkView(m1).AddrIsAtLeft(addr, 1, &offset)) { 594 // The address is in the chunk's left redzone, so maybe it is actually 595 // a right buffer overflow from the other chunk to the left. 596 // Search a bit to the left to see if there is another chunk. 597 AsanChunk *m2 = 0; 598 for (uptr l = 1; l < GetPageSizeCached(); l++) { 599 m2 = GetAsanChunkByAddr(addr - l); 600 if (m2 == m1) continue; // Still the same chunk. 601 break; 602 } 603 if (m2 && AsanChunkView(m2).AddrIsAtRight(addr, 1, &offset)) 604 m1 = ChooseChunk(addr, m2, m1); 605 } 606 return AsanChunkView(m1); 607} 608 609void AsanThreadLocalMallocStorage::CommitBack() { 610 AllocatorCache *ac = GetAllocatorCache(this); 611 quarantine.Drain(GetQuarantineCache(this), QuarantineCallback(ac)); 612 allocator.SwallowCache(GetAllocatorCache(this)); 613} 614 615void PrintInternalAllocatorStats() { 616 allocator.PrintStats(); 617} 618 619SANITIZER_INTERFACE_ATTRIBUTE 620void *asan_memalign(uptr alignment, uptr size, StackTrace *stack, 621 AllocType alloc_type) { 622 return Allocate(size, alignment, stack, alloc_type, true); 623} 624 625SANITIZER_INTERFACE_ATTRIBUTE 626void asan_free(void *ptr, StackTrace *stack, AllocType alloc_type) { 627 Deallocate(ptr, stack, alloc_type); 628} 629 630SANITIZER_INTERFACE_ATTRIBUTE 631void *asan_malloc(uptr size, StackTrace *stack) { 632 return Allocate(size, 8, stack, FROM_MALLOC, true); 633} 634 635void *asan_calloc(uptr nmemb, uptr size, StackTrace *stack) { 636 if (CallocShouldReturnNullDueToOverflow(size, nmemb)) return 0; 637 void *ptr = Allocate(nmemb * size, 8, stack, FROM_MALLOC, false); 638 // If the memory comes from the secondary allocator no need to clear it 639 // as it comes directly from mmap. 640 if (ptr && allocator.FromPrimary(ptr)) 641 REAL(memset)(ptr, 0, nmemb * size); 642 return ptr; 643} 644 645void *asan_realloc(void *p, uptr size, StackTrace *stack) { 646 if (p == 0) 647 return Allocate(size, 8, stack, FROM_MALLOC, true); 648 if (size == 0) { 649 Deallocate(p, stack, FROM_MALLOC); 650 return 0; 651 } 652 return Reallocate(p, size, stack); 653} 654 655void *asan_valloc(uptr size, StackTrace *stack) { 656 return Allocate(size, GetPageSizeCached(), stack, FROM_MALLOC, true); 657} 658 659void *asan_pvalloc(uptr size, StackTrace *stack) { 660 uptr PageSize = GetPageSizeCached(); 661 size = RoundUpTo(size, PageSize); 662 if (size == 0) { 663 // pvalloc(0) should allocate one page. 664 size = PageSize; 665 } 666 return Allocate(size, PageSize, stack, FROM_MALLOC, true); 667} 668 669int asan_posix_memalign(void **memptr, uptr alignment, uptr size, 670 StackTrace *stack) { 671 void *ptr = Allocate(size, alignment, stack, FROM_MALLOC, true); 672 CHECK(IsAligned((uptr)ptr, alignment)); 673 *memptr = ptr; 674 return 0; 675} 676 677uptr asan_malloc_usable_size(void *ptr, StackTrace *stack) { 678 CHECK(stack); 679 if (ptr == 0) return 0; 680 uptr usable_size = AllocationSize(reinterpret_cast<uptr>(ptr)); 681 if (flags()->check_malloc_usable_size && (usable_size == 0)) 682 ReportMallocUsableSizeNotOwned((uptr)ptr, stack); 683 return usable_size; 684} 685 686uptr asan_mz_size(const void *ptr) { 687 return AllocationSize(reinterpret_cast<uptr>(ptr)); 688} 689 690void asan_mz_force_lock() { 691 allocator.ForceLock(); 692 fallback_mutex.Lock(); 693} 694 695void asan_mz_force_unlock() { 696 fallback_mutex.Unlock(); 697 allocator.ForceUnlock(); 698} 699 700} // namespace __asan 701 702// --- Implementation of LSan-specific functions --- {{{1 703namespace __lsan { 704void LockAllocator() { 705 __asan::allocator.ForceLock(); 706} 707 708void UnlockAllocator() { 709 __asan::allocator.ForceUnlock(); 710} 711 712void GetAllocatorGlobalRange(uptr *begin, uptr *end) { 713 *begin = (uptr)&__asan::allocator; 714 *end = *begin + sizeof(__asan::allocator); 715} 716 717void *PointsIntoChunk(void* p) { 718 uptr addr = reinterpret_cast<uptr>(p); 719 __asan::AsanChunk *m = __asan::GetAsanChunkByAddrFastLocked(addr); 720 if (!m) return 0; 721 uptr chunk = m->Beg(); 722 if ((m->chunk_state == __asan::CHUNK_ALLOCATED) && m->AddrIsInside(addr)) 723 return reinterpret_cast<void *>(chunk); 724 return 0; 725} 726 727void *GetUserBegin(void *p) { 728 __asan::AsanChunk *m = 729 __asan::GetAsanChunkByAddrFastLocked(reinterpret_cast<uptr>(p)); 730 CHECK(m); 731 return reinterpret_cast<void *>(m->Beg()); 732} 733 734LsanMetadata::LsanMetadata(void *chunk) { 735 uptr addr = reinterpret_cast<uptr>(chunk); 736 metadata_ = reinterpret_cast<void *>(addr - __asan::kChunkHeaderSize); 737} 738 739bool LsanMetadata::allocated() const { 740 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_); 741 return m->chunk_state == __asan::CHUNK_ALLOCATED; 742} 743 744ChunkTag LsanMetadata::tag() const { 745 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_); 746 return static_cast<ChunkTag>(m->lsan_tag); 747} 748 749void LsanMetadata::set_tag(ChunkTag value) { 750 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_); 751 m->lsan_tag = value; 752} 753 754uptr LsanMetadata::requested_size() const { 755 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_); 756 return m->UsedSize(); 757} 758 759u32 LsanMetadata::stack_trace_id() const { 760 __asan::AsanChunk *m = reinterpret_cast<__asan::AsanChunk *>(metadata_); 761 return m->alloc_context_id; 762} 763 764template <typename Callable> void ForEachChunk(Callable const &callback) { 765 __asan::allocator.ForEachChunk(callback); 766} 767#if CAN_SANITIZE_LEAKS 768template void ForEachChunk<ProcessPlatformSpecificAllocationsCb>( 769 ProcessPlatformSpecificAllocationsCb const &callback); 770template void ForEachChunk<PrintLeakedCb>(PrintLeakedCb const &callback); 771template void ForEachChunk<CollectLeaksCb>(CollectLeaksCb const &callback); 772template void ForEachChunk<MarkIndirectlyLeakedCb>( 773 MarkIndirectlyLeakedCb const &callback); 774template void ForEachChunk<CollectSuppressedCb>( 775 CollectSuppressedCb const &callback); 776#endif // CAN_SANITIZE_LEAKS 777 778IgnoreObjectResult IgnoreObjectLocked(const void *p) { 779 uptr addr = reinterpret_cast<uptr>(p); 780 __asan::AsanChunk *m = __asan::GetAsanChunkByAddr(addr); 781 if (!m) return kIgnoreObjectInvalid; 782 if ((m->chunk_state == __asan::CHUNK_ALLOCATED) && m->AddrIsInside(addr)) { 783 if (m->lsan_tag == kSuppressed) 784 return kIgnoreObjectAlreadyIgnored; 785 m->lsan_tag = __lsan::kSuppressed; 786 return kIgnoreObjectSuccess; 787 } else { 788 return kIgnoreObjectInvalid; 789 } 790} 791} // namespace __lsan 792 793extern "C" { 794SANITIZER_INTERFACE_ATTRIBUTE 795void __lsan_disable() { 796 __asan_init(); 797 __asan::AsanThread *t = __asan::GetCurrentThread(); 798 CHECK(t); 799 t->disable_lsan(); 800} 801 802SANITIZER_INTERFACE_ATTRIBUTE 803void __lsan_enable() { 804 __asan_init(); 805 __asan::AsanThread *t = __asan::GetCurrentThread(); 806 CHECK(t); 807 t->enable_lsan(); 808} 809} // extern "C" 810 811// ---------------------- Interface ---------------- {{{1 812using namespace __asan; // NOLINT 813 814// ASan allocator doesn't reserve extra bytes, so normally we would 815// just return "size". We don't want to expose our redzone sizes, etc here. 816uptr __asan_get_estimated_allocated_size(uptr size) { 817 return size; 818} 819 820bool __asan_get_ownership(const void *p) { 821 uptr ptr = reinterpret_cast<uptr>(p); 822 return (AllocationSize(ptr) > 0); 823} 824 825uptr __asan_get_allocated_size(const void *p) { 826 if (p == 0) return 0; 827 uptr ptr = reinterpret_cast<uptr>(p); 828 uptr allocated_size = AllocationSize(ptr); 829 // Die if p is not malloced or if it is already freed. 830 if (allocated_size == 0) { 831 GET_STACK_TRACE_FATAL_HERE; 832 ReportAsanGetAllocatedSizeNotOwned(ptr, &stack); 833 } 834 return allocated_size; 835} 836 837#if !SANITIZER_SUPPORTS_WEAK_HOOKS 838// Provide default (no-op) implementation of malloc hooks. 839extern "C" { 840SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE 841void __asan_malloc_hook(void *ptr, uptr size) { 842 (void)ptr; 843 (void)size; 844} 845SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE 846void __asan_free_hook(void *ptr) { 847 (void)ptr; 848} 849} // extern "C" 850#endif 851