From: Eric Wheeler Date: Mon, 7 Mar 2016 23:17:50 +0000 (-0800) Subject: bcache: fix cache_set_flush() NULL pointer dereference on OOM X-Git-Tag: v4.6-rc1~96^2~6 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=f8b11260a445169989d01df75d35af0f56178f95;p=karo-tx-linux.git bcache: fix cache_set_flush() NULL pointer dereference on OOM 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 --- diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 6b07a0c8c729..a296425a7270 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1373,6 +1373,9 @@ 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);