libsanitizer/lsan/lsan_allocator.cpp

   1 //=-- lsan_allocator.cpp --------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file is a part of LeakSanitizer.
  10 // See lsan_allocator.h for details.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "lsan_allocator.h"
  15
  16 #include "sanitizer_common/sanitizer_allocator.h"
  17 #include "sanitizer_common/sanitizer_allocator_checks.h"
  18 #include "sanitizer_common/sanitizer_allocator_interface.h"
  19 #include "sanitizer_common/sanitizer_allocator_report.h"
  20 #include "sanitizer_common/sanitizer_errno.h"
  21 #include "sanitizer_common/sanitizer_internal_defs.h"
  22 #include "sanitizer_common/sanitizer_stackdepot.h"
  23 #include "sanitizer_common/sanitizer_stacktrace.h"
  24 #include "lsan_common.h"
  25
  26 extern "C" void *memset(void *ptr, int value, uptr num);
  27
  28 namespace __lsan {
  29 #if defined(__i386__) || defined(__arm__)
  30 static const uptr kMaxAllowedMallocSize = 1UL << 30;
  31 #elif defined(__mips64) || defined(__aarch64__)
  32 static const uptr kMaxAllowedMallocSize = 4UL << 30;
  33 #else
  34 static const uptr kMaxAllowedMallocSize = 8UL << 30;
  35 #endif
  36
  37 static Allocator allocator;
  38
  39 static uptr max_malloc_size;
  40
  41 void InitializeAllocator() {
  42   SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
  43   allocator.InitLinkerInitialized(
  44       common_flags()->allocator_release_to_os_interval_ms);
  45   if (common_flags()->max_allocation_size_mb)
  46     max_malloc_size = Min(common_flags()->max_allocation_size_mb << 20,
  47                           kMaxAllowedMallocSize);
  48   else
  49     max_malloc_size = kMaxAllowedMallocSize;
  50 }
  51
  52 void AllocatorThreadFinish() {
  53   allocator.SwallowCache(GetAllocatorCache());
  54 }
  55
  56 static ChunkMetadata *Metadata(const void *p) {
  57   return reinterpret_cast<ChunkMetadata *>(allocator.GetMetaData(p));
  58 }
  59
  60 static void RegisterAllocation(const StackTrace &stack, void *p, uptr size) {
  61   if (!p) return;
  62   ChunkMetadata *m = Metadata(p);
  63   CHECK(m);
  64   m->tag = DisabledInThisThread() ? kIgnored : kDirectlyLeaked;
  65   m->stack_trace_id = StackDepotPut(stack);
  66   m->requested_size = size;
  67   atomic_store(reinterpret_cast<atomic_uint8_t *>(m), 1, memory_order_relaxed);
  68 }
  69
  70 static void RegisterDeallocation(void *p) {
  71   if (!p) return;
  72   ChunkMetadata *m = Metadata(p);
  73   CHECK(m);
  74   atomic_store(reinterpret_cast<atomic_uint8_t *>(m), 0, memory_order_relaxed);
  75 }
  76
  77 static void *ReportAllocationSizeTooBig(uptr size, const StackTrace &stack) {
  78   if (AllocatorMayReturnNull()) {
  79     Report("WARNING: LeakSanitizer failed to allocate 0x%zx bytes\n", size);
  80     return nullptr;
  81   }
  82   ReportAllocationSizeTooBig(size, max_malloc_size, &stack);
  83 }
  84
  85 void *Allocate(const StackTrace &stack, uptr size, uptr alignment,
  86                bool cleared) {
  87   if (size == 0)
  88     size = 1;
  89   if (size > max_malloc_size)
  90     return ReportAllocationSizeTooBig(size, stack);
  91   void *p = allocator.Allocate(GetAllocatorCache(), size, alignment);
  92   if (UNLIKELY(!p)) {
  93     SetAllocatorOutOfMemory();
  94     if (AllocatorMayReturnNull())
  95       return nullptr;
  96     ReportOutOfMemory(size, &stack);
  97   }
  98   // Do not rely on the allocator to clear the memory (it's slow).
  99   if (cleared && allocator.FromPrimary(p))
 100     memset(p, 0, size);
 101   RegisterAllocation(stack, p, size);
 102   if (&__sanitizer_malloc_hook) __sanitizer_malloc_hook(p, size);
 103   RunMallocHooks(p, size);
 104   return p;
 105 }
 106
 107 static void *Calloc(uptr nmemb, uptr size, const StackTrace &stack) {
 108   if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
 109     if (AllocatorMayReturnNull())
 110       return nullptr;
 111     ReportCallocOverflow(nmemb, size, &stack);
 112   }
 113   size *= nmemb;
 114   return Allocate(stack, size, 1, true);
 115 }
 116
 117 void Deallocate(void *p) {
 118   if (&__sanitizer_free_hook) __sanitizer_free_hook(p);
 119   RunFreeHooks(p);
 120   RegisterDeallocation(p);
 121   allocator.Deallocate(GetAllocatorCache(), p);
 122 }
 123
 124 void *Reallocate(const StackTrace &stack, void *p, uptr new_size,
 125                  uptr alignment) {
 126   RegisterDeallocation(p);
 127   if (new_size > max_malloc_size) {
 128     allocator.Deallocate(GetAllocatorCache(), p);
 129     return ReportAllocationSizeTooBig(new_size, stack);
 130   }
 131   p = allocator.Reallocate(GetAllocatorCache(), p, new_size, alignment);
 132   RegisterAllocation(stack, p, new_size);
 133   return p;
 134 }
 135
 136 void GetAllocatorCacheRange(uptr *begin, uptr *end) {
 137   *begin = (uptr)GetAllocatorCache();
 138   *end = *begin + sizeof(AllocatorCache);
 139 }
 140
 141 uptr GetMallocUsableSize(const void *p) {
 142   ChunkMetadata *m = Metadata(p);
 143   if (!m) return 0;
 144   return m->requested_size;
 145 }
 146
 147 int lsan_posix_memalign(void **memptr, uptr alignment, uptr size,
 148                         const StackTrace &stack) {
 149   if (UNLIKELY(!CheckPosixMemalignAlignment(alignment))) {
 150     if (AllocatorMayReturnNull())
 151       return errno_EINVAL;
 152     ReportInvalidPosixMemalignAlignment(alignment, &stack);
 153   }
 154   void *ptr = Allocate(stack, size, alignment, kAlwaysClearMemory);
 155   if (UNLIKELY(!ptr))
 156     // OOM error is already taken care of by Allocate.
 157     return errno_ENOMEM;
 158   CHECK(IsAligned((uptr)ptr, alignment));
 159   *memptr = ptr;
 160   return 0;
 161 }
 162
 163 void *lsan_aligned_alloc(uptr alignment, uptr size, const StackTrace &stack) {
 164   if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(alignment, size))) {
 165     errno = errno_EINVAL;
 166     if (AllocatorMayReturnNull())
 167       return nullptr;
 168     ReportInvalidAlignedAllocAlignment(size, alignment, &stack);
 169   }
 170   return SetErrnoOnNull(Allocate(stack, size, alignment, kAlwaysClearMemory));
 171 }
 172
 173 void *lsan_memalign(uptr alignment, uptr size, const StackTrace &stack) {
 174   if (UNLIKELY(!IsPowerOfTwo(alignment))) {
 175     errno = errno_EINVAL;
 176     if (AllocatorMayReturnNull())
 177       return nullptr;
 178     ReportInvalidAllocationAlignment(alignment, &stack);
 179   }
 180   return SetErrnoOnNull(Allocate(stack, size, alignment, kAlwaysClearMemory));
 181 }
 182
 183 void *lsan_malloc(uptr size, const StackTrace &stack) {
 184   return SetErrnoOnNull(Allocate(stack, size, 1, kAlwaysClearMemory));
 185 }
 186
 187 void lsan_free(void *p) {
 188   Deallocate(p);
 189 }
 190
 191 void *lsan_realloc(void *p, uptr size, const StackTrace &stack) {
 192   return SetErrnoOnNull(Reallocate(stack, p, size, 1));
 193 }
 194
 195 void *lsan_reallocarray(void *ptr, uptr nmemb, uptr size,
 196                         const StackTrace &stack) {
 197   if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
 198     errno = errno_ENOMEM;
 199     if (AllocatorMayReturnNull())
 200       return nullptr;
 201     ReportReallocArrayOverflow(nmemb, size, &stack);
 202   }
 203   return lsan_realloc(ptr, nmemb * size, stack);
 204 }
 205
 206 void *lsan_calloc(uptr nmemb, uptr size, const StackTrace &stack) {
 207   return SetErrnoOnNull(Calloc(nmemb, size, stack));
 208 }
 209
 210 void *lsan_valloc(uptr size, const StackTrace &stack) {
 211   return SetErrnoOnNull(
 212       Allocate(stack, size, GetPageSizeCached(), kAlwaysClearMemory));
 213 }
 214
 215 void *lsan_pvalloc(uptr size, const StackTrace &stack) {
 216   uptr PageSize = GetPageSizeCached();
 217   if (UNLIKELY(CheckForPvallocOverflow(size, PageSize))) {
 218     errno = errno_ENOMEM;
 219     if (AllocatorMayReturnNull())
 220       return nullptr;
 221     ReportPvallocOverflow(size, &stack);
 222   }
 223   // pvalloc(0) should allocate one page.
 224   size = size ? RoundUpTo(size, PageSize) : PageSize;
 225   return SetErrnoOnNull(Allocate(stack, size, PageSize, kAlwaysClearMemory));
 226 }
 227
 228 uptr lsan_mz_size(const void *p) {
 229   return GetMallocUsableSize(p);
 230 }
 231
 232 ///// Interface to the common LSan module. /////
 233
 234 void LockAllocator() {
 235   allocator.ForceLock();
 236 }
 237
 238 void UnlockAllocator() {
 239   allocator.ForceUnlock();
 240 }
 241
 242 void GetAllocatorGlobalRange(uptr *begin, uptr *end) {
 243   *begin = (uptr)&allocator;
 244   *end = *begin + sizeof(allocator);
 245 }
 246
 247 uptr PointsIntoChunk(void* p) {
 248   uptr addr = reinterpret_cast<uptr>(p);
 249   uptr chunk = reinterpret_cast<uptr>(allocator.GetBlockBeginFastLocked(p));
 250   if (!chunk) return 0;
 251   // LargeMmapAllocator considers pointers to the meta-region of a chunk to be
 252   // valid, but we don't want that.
 253   if (addr < chunk) return 0;
 254   ChunkMetadata *m = Metadata(reinterpret_cast<void *>(chunk));
 255   CHECK(m);
 256   if (!m->allocated)
 257     return 0;
 258   if (addr < chunk + m->requested_size)
 259     return chunk;
 260   if (IsSpecialCaseOfOperatorNew0(chunk, m->requested_size, addr))
 261     return chunk;
 262   return 0;
 263 }
 264
 265 uptr GetUserBegin(uptr chunk) {
 266   return chunk;
 267 }
 268
 269 LsanMetadata::LsanMetadata(uptr chunk) {
 270   metadata_ = Metadata(reinterpret_cast<void *>(chunk));
 271   CHECK(metadata_);
 272 }
 273
 274 bool LsanMetadata::allocated() const {
 275   return reinterpret_cast<ChunkMetadata *>(metadata_)->allocated;
 276 }
 277
 278 ChunkTag LsanMetadata::tag() const {
 279   return reinterpret_cast<ChunkMetadata *>(metadata_)->tag;
 280 }
 281
 282 void LsanMetadata::set_tag(ChunkTag value) {
 283   reinterpret_cast<ChunkMetadata *>(metadata_)->tag = value;
 284 }
 285
 286 uptr LsanMetadata::requested_size() const {
 287   return reinterpret_cast<ChunkMetadata *>(metadata_)->requested_size;
 288 }
 289
 290 u32 LsanMetadata::stack_trace_id() const {
 291   return reinterpret_cast<ChunkMetadata *>(metadata_)->stack_trace_id;
 292 }
 293
 294 void ForEachChunk(ForEachChunkCallback callback, void *arg) {
 295   allocator.ForEachChunk(callback, arg);
 296 }
 297
 298 IgnoreObjectResult IgnoreObjectLocked(const void *p) {
 299   void *chunk = allocator.GetBlockBegin(p);
 300   if (!chunk || p < chunk) return kIgnoreObjectInvalid;
 301   ChunkMetadata *m = Metadata(chunk);
 302   CHECK(m);
 303   if (m->allocated && (uptr)p < (uptr)chunk + m->requested_size) {
 304     if (m->tag == kIgnored)
 305       return kIgnoreObjectAlreadyIgnored;
 306     m->tag = kIgnored;
 307     return kIgnoreObjectSuccess;
 308   } else {
 309     return kIgnoreObjectInvalid;
 310   }
 311 }
 312 } // namespace __lsan
 313
 314 using namespace __lsan;
 315
 316 extern "C" {
 317 SANITIZER_INTERFACE_ATTRIBUTE
 318 uptr __sanitizer_get_current_allocated_bytes() {
 319   uptr stats[AllocatorStatCount];
 320   allocator.GetStats(stats);
 321   return stats[AllocatorStatAllocated];
 322 }
 323
 324 SANITIZER_INTERFACE_ATTRIBUTE
 325 uptr __sanitizer_get_heap_size() {
 326   uptr stats[AllocatorStatCount];
 327   allocator.GetStats(stats);
 328   return stats[AllocatorStatMapped];
 329 }
 330
 331 SANITIZER_INTERFACE_ATTRIBUTE
 332 uptr __sanitizer_get_free_bytes() { return 0; }
 333
 334 SANITIZER_INTERFACE_ATTRIBUTE
 335 uptr __sanitizer_get_unmapped_bytes() { return 0; }
 336
 337 SANITIZER_INTERFACE_ATTRIBUTE
 338 uptr __sanitizer_get_estimated_allocated_size(uptr size) { return size; }
 339
 340 SANITIZER_INTERFACE_ATTRIBUTE
 341 int __sanitizer_get_ownership(const void *p) { return Metadata(p) != nullptr; }
 342
 343 SANITIZER_INTERFACE_ATTRIBUTE
 344 uptr __sanitizer_get_allocated_size(const void *p) {
 345   return GetMallocUsableSize(p);
 346 }
 347
 348 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
 349 // Provide default (no-op) implementation of malloc hooks.
 350 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 351 void __sanitizer_malloc_hook(void *ptr, uptr size) {
 352   (void)ptr;
 353   (void)size;
 354 }
 355 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 356 void __sanitizer_free_hook(void *ptr) {
 357   (void)ptr;
 358 }
 359 #endif
 360 } // extern "C"