From a8ff421a3e97c8a5a89208efc1621e88f48fde5f Mon Sep 17 00:00:00 2001 From: Eric Wheeler Date: Mon, 7 Mar 2016 15:17:50 -0800 Subject: [PATCH] bcache: fix cache_set_flush() NULL pointer dereference on OOM Orabug: 23331099 [ Upstream commit f8b11260a445169989d01df75d35af0f56178f95 ] When bch_cache_set_alloc() fails to kzalloc the cache_set, the asyncronous closure handling tries to dereference a cache_set that hadn't yet been allocated inside of cache_set_flush() which is called by __cache_set_unregister() during cleanup. This appears to happen only during an OOM condition on bcache_register. Signed-off-by: Eric Wheeler Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin (cherry picked from commit d09a05998d79dcfaa25de84624dce9f806fe4e7c) Signed-off-by: Dan Duval --- drivers/md/bcache/super.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 2d0650defd37..2a102834c2ee 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1404,6 +1404,9 @@ static void cache_set_flush(struct closure *cl) struct btree *b; unsigned i; + if (!c) + closure_return(cl); + bch_cache_accounting_destroy(&c->accounting); kobject_put(&c->internal); -- 2.50.1