diff options
Diffstat (limited to 'src/backend/utils/mmgr/aset.c')
| -rw-r--r-- | src/backend/utils/mmgr/aset.c | 65 |
1 files changed, 45 insertions, 20 deletions
diff --git a/src/backend/utils/mmgr/aset.c b/src/backend/utils/mmgr/aset.c index 6a111c78329..de643779f06 100644 --- a/src/backend/utils/mmgr/aset.c +++ b/src/backend/utils/mmgr/aset.c @@ -308,6 +308,37 @@ AllocSetFreeIndex(Size size) return idx; } +#ifdef CLOBBER_FREED_MEMORY + +/* Wipe freed memory for debugging purposes */ +static void +wipe_mem(void *ptr, size_t size) +{ + memset(ptr, 0x7F, size); +} +#endif + +#ifdef MEMORY_CONTEXT_CHECKING +static void +set_sentinel(void *base, Size offset) +{ + char *ptr = (char *) base + offset; + + *ptr = 0x7E; +} + +static bool +sentinel_ok(const void *base, Size offset) +{ + const char *ptr = (const char *) base + offset; + bool ret; + + ret = *ptr == 0x7E; + + return ret; +} +#endif + #ifdef RANDOMIZE_ALLOCATED_MEMORY /* @@ -492,8 +523,7 @@ AllocSetReset(MemoryContext context) char *datastart = ((char *) block) + ALLOC_BLOCKHDRSZ; #ifdef CLOBBER_FREED_MEMORY - /* Wipe freed memory for debugging purposes */ - memset(datastart, 0x7F, block->freeptr - datastart); + wipe_mem(datastart, block->freeptr - datastart); #endif block->freeptr = datastart; block->next = NULL; @@ -502,8 +532,7 @@ AllocSetReset(MemoryContext context) { /* Normal case, release the block */ #ifdef CLOBBER_FREED_MEMORY - /* Wipe freed memory for debugging purposes */ - memset(block, 0x7F, block->freeptr - ((char *) block)); + wipe_mem(block, block->freeptr - ((char *) block)); #endif free(block); } @@ -545,8 +574,7 @@ AllocSetDelete(MemoryContext context) AllocBlock next = block->next; #ifdef CLOBBER_FREED_MEMORY - /* Wipe freed memory for debugging purposes */ - memset(block, 0x7F, block->freeptr - ((char *) block)); + wipe_mem(block, block->freeptr - ((char *) block)); #endif free(block); block = next; @@ -598,7 +626,7 @@ AllocSetAlloc(MemoryContext context, Size size) chunk->requested_size = size; /* set mark to catch clobber of "unused" space */ if (size < chunk_size) - ((char *) AllocChunkGetPointer(chunk))[size] = 0x7E; + set_sentinel(AllocChunkGetPointer(chunk), size); #endif #ifdef RANDOMIZE_ALLOCATED_MEMORY /* fill the allocated space with junk */ @@ -644,7 +672,7 @@ AllocSetAlloc(MemoryContext context, Size size) chunk->requested_size = size; /* set mark to catch clobber of "unused" space */ if (size < chunk->size) - ((char *) AllocChunkGetPointer(chunk))[size] = 0x7E; + set_sentinel(AllocChunkGetPointer(chunk), size); #endif #ifdef RANDOMIZE_ALLOCATED_MEMORY /* fill the allocated space with junk */ @@ -801,7 +829,7 @@ AllocSetAlloc(MemoryContext context, Size size) chunk->requested_size = size; /* set mark to catch clobber of "unused" space */ if (size < chunk->size) - ((char *) AllocChunkGetPointer(chunk))[size] = 0x7E; + set_sentinel(AllocChunkGetPointer(chunk), size); #endif #ifdef RANDOMIZE_ALLOCATED_MEMORY /* fill the allocated space with junk */ @@ -827,7 +855,7 @@ AllocSetFree(MemoryContext context, void *pointer) #ifdef MEMORY_CONTEXT_CHECKING /* Test for someone scribbling on unused space in chunk */ if (chunk->requested_size < chunk->size) - if (((char *) pointer)[chunk->requested_size] != 0x7E) + if (!sentinel_ok(pointer, chunk->requested_size)) elog(WARNING, "detected write past chunk end in %s %p", set->header.name, chunk); #endif @@ -860,8 +888,7 @@ AllocSetFree(MemoryContext context, void *pointer) else prevblock->next = block->next; #ifdef CLOBBER_FREED_MEMORY - /* Wipe freed memory for debugging purposes */ - memset(block, 0x7F, block->freeptr - ((char *) block)); + wipe_mem(block, block->freeptr - ((char *) block)); #endif free(block); } @@ -873,8 +900,7 @@ AllocSetFree(MemoryContext context, void *pointer) chunk->aset = (void *) set->freelist[fidx]; #ifdef CLOBBER_FREED_MEMORY - /* Wipe freed memory for debugging purposes */ - memset(pointer, 0x7F, chunk->size); + wipe_mem(pointer, chunk->size); #endif #ifdef MEMORY_CONTEXT_CHECKING @@ -901,7 +927,7 @@ AllocSetRealloc(MemoryContext context, void *pointer, Size size) #ifdef MEMORY_CONTEXT_CHECKING /* Test for someone scribbling on unused space in chunk */ if (chunk->requested_size < oldsize) - if (((char *) pointer)[chunk->requested_size] != 0x7E) + if (!sentinel_ok(pointer, chunk->requested_size)) elog(WARNING, "detected write past chunk end in %s %p", set->header.name, chunk); #endif @@ -924,7 +950,7 @@ AllocSetRealloc(MemoryContext context, void *pointer, Size size) chunk->requested_size = size; /* set mark to catch clobber of "unused" space */ if (size < oldsize) - ((char *) pointer)[size] = 0x7E; + set_sentinel(pointer, size); #endif return pointer; } @@ -987,7 +1013,7 @@ AllocSetRealloc(MemoryContext context, void *pointer, Size size) chunk->requested_size = size; /* set mark to catch clobber of "unused" space */ if (size < chunk->size) - ((char *) AllocChunkGetPointer(chunk))[size] = 0x7E; + set_sentinel(AllocChunkGetPointer(chunk), size); #endif return AllocChunkGetPointer(chunk); @@ -1136,11 +1162,9 @@ AllocSetCheck(MemoryContext context) AllocChunk chunk = (AllocChunk) bpoz; Size chsize, dsize; - char *chdata_end; chsize = chunk->size; /* aligned chunk size */ dsize = chunk->requested_size; /* real data */ - chdata_end = ((char *) chunk) + (ALLOC_CHUNKHDRSZ + dsize); /* * Check chunk size @@ -1170,7 +1194,8 @@ AllocSetCheck(MemoryContext context) /* * Check for overwrite of "unallocated" space in chunk */ - if (dsize > 0 && dsize < chsize && *chdata_end != 0x7E) + if (dsize > 0 && dsize < chsize && + !sentinel_ok(chunk, ALLOC_CHUNKHDRSZ + dsize)) elog(WARNING, "problem in alloc set %s: detected write past chunk end in block %p, chunk %p", name, block, chunk); 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