tree bf2a6b2462f44bc2977ea1b5bc2c0e552444650c
parent c9a77a792003ce9d70df8937c8c87aee6e177149
author Vladimir Davydov <vdavydov@virtuozzo.com> 1446777911 -0800
committer Linus Torvalds <torvalds@linux-foundation.org> 1446780888 -0800

mm/slab_common.c: clear pointers to per memcg caches on destroy

Currently, we do not clear pointers to per memcg caches in the
memcg_params.memcg_caches array when a global cache is destroyed with
kmem_cache_destroy.

This is fine if the global cache does get destroyed.  However, a cache can
be left on the list if it still has active objects when kmem_cache_destroy
is called (due to a memory leak).  If this happens, the entries in the
array will point to already freed areas, which is likely to result in data
corruption when the cache is reused (via slab merging).

Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>