lib/asan/asan_allocator.cpp

70 // The memory chunk allocated from the underlying allocator looks like this:
151   // The chunk is allocated and not yet freed.
153   // The chunk was freed and put into quarantine zone.
203       // contents of deallocated chunk, confusing GetAsanChunk lookup.
253   // We are about to unmap a chunk of user memory.
346   void RePoisonChunk(uptr chunk) {
347     // This could be a user-facing chunk (with redzones), or some internal
348     // housekeeping chunk, like TransferBatch. Start by assuming the former.
349     AsanChunk *ac = GetAsanChunk((void *)chunk);
350     uptr allocated_size = allocator.GetActuallyAllocatedSize((void *)chunk);
355       uptr chunk_end = chunk + allocated_size;
356       if (chunk < beg && beg < end && end <= chunk_end) {
358         PoisonShadow(chunk, beg - chunk, kAsanHeapLeftRedzoneMagic);
369     PoisonShadow(chunk, allocated_size, kAsanHeapLeftRedzoneMagic);
381           [](uptr chunk, void *alloc) {
382             ((Allocator *)alloc)->RePoisonChunk(chunk);
437     // Prefer an allocated chunk over freed chunk and freed chunk
438     // over available chunk.
541       // chunk. This is possible if CanPoisonMemory() was false for some
604   // Set quarantine flag if chunk is allocated, issue ASan error report on
614       // It's not safe to push a chunk in quarantine on invalid free.
623   // Expects the chunk to already be marked as quarantined by using
633       // We have to skip the chunk header, it contains free_context_id.
683     // Must mark the chunk as quarantined before any changes to its metadata.
684     // Do not quarantine given chunk if we failed to set CHUNK_QUARANTINE flag.
805       // The address is in the chunk's left redzone, so maybe it is actually
806       // a right buffer overflow from the other chunk before.
807       // Search a bit before to see if there is another chunk.
811         if (m2 == m1) continue;  // Still the same chunk.
1088   uptr chunk = m->Beg();
1090     return chunk;
1091   if (IsSpecialCaseOfOperatorNew0(chunk, m->UsedSize(), addr))
1092     return chunk;
1096 uptr GetUserBegin(uptr chunk) {
1097   // FIXME: All usecases provide chunk address, GetAsanChunkByAddrFastLocked is
1099   __asan::AsanChunk *m = __asan::instance.GetAsanChunkByAddrFastLocked(chunk);
1103 LsanMetadata::LsanMetadata(uptr chunk) {
1104   metadata_ = chunk ? reinterpret_cast<void *>(chunk - __asan::kChunkHeaderSize)