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| author | H.J. Lu <hjl.tools@gmail.com> | 2012-09-08 15:36:50 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2012-09-08 15:36:50 -0700 |
| commit | 67d875851e833ab93dd8aa5fb934e79d094da48d (patch) | |
| tree | 8623c1b2f9eb472c05cab2a8a29dd29587c0bd1b | |
| parent | 3d9b46b3500566163815747173002d3d0bbb9b2f (diff) | |
| download | glibc-67d875851e833ab93dd8aa5fb934e79d094da48d.tar.gz glibc-67d875851e833ab93dd8aa5fb934e79d094da48d.tar.xz glibc-67d875851e833ab93dd8aa5fb934e79d094da48d.zip | |
Properly handle fencepost with MALLOC_ALIGN_MASK hjl/pr14562/master
| -rw-r--r-- | ChangeLog.pr14562 | 5 | ||||
| -rw-r--r-- | malloc/arena.c | 7 |
2 files changed, 10 insertions, 2 deletions
diff --git a/ChangeLog.pr14562 b/ChangeLog.pr14562 new file mode 100644 index 0000000000..b92843d223 --- /dev/null +++ b/ChangeLog.pr14562 @@ -0,0 +1,5 @@ +2012-09-08 H.J. Lu <hongjiu.lu@intel.com> + + [BZ #14562] + * malloc/arena.c (heap_trim): Properly get fencepost and adjust + new chunk size with MALLOC_ALIGN_MASK. diff --git a/malloc/arena.c b/malloc/arena.c index 97c0b909cc..dd4f3e343c 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -655,15 +655,18 @@ heap_trim(heap_info *heap, size_t pad) unsigned long pagesz = GLRO(dl_pagesize); mchunkptr top_chunk = top(ar_ptr), p, bck, fwd; heap_info *prev_heap; - long new_size, top_size, extra; + long new_size, top_size, extra, misalign; /* Can this heap go away completely? */ while(top_chunk == chunk_at_offset(heap, sizeof(*heap))) { prev_heap = heap->prev; p = chunk_at_offset(prev_heap, prev_heap->size - (MINSIZE-2*SIZE_SZ)); + /* fencepost must be properly aligned. */ + misalign = ((long) p) & MALLOC_ALIGN_MASK; + p = (mchunkptr)(((unsigned long) p) & ~MALLOC_ALIGN_MASK); assert(p->size == (0|PREV_INUSE)); /* must be fencepost */ p = prev_chunk(p); - new_size = chunksize(p) + (MINSIZE-2*SIZE_SZ); + new_size = chunksize(p) + (MINSIZE-2*SIZE_SZ) + misalign; assert(new_size>0 && new_size<(long)(2*MINSIZE)); if(!prev_inuse(p)) new_size += p->prev_size; |