Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933190AbcDKNj3 (ORCPT ); Mon, 11 Apr 2016 09:39:29 -0400 Received: from mx2.suse.de ([195.135.220.15]:37483 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932527AbcDKNYO (ORCPT ); Mon, 11 Apr 2016 09:24:14 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Eric Wheeler , Eric Wheeler , Jiri Slaby Subject: [PATCH 3.12 74/98] bcache: fix cache_set_flush() NULL pointer dereference on OOM Date: Mon, 11 Apr 2016 15:23:16 +0200 Message-Id: X-Mailer: git-send-email 2.8.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1089 Lines: 36 From: Eric Wheeler 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit f8b11260a445169989d01df75d35af0f56178f95 upstream. 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 Signed-off-by: Jiri Slaby --- 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 70d396ee69e2..2a697b3d58c5 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1343,6 +1343,9 @@ 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); -- 2.8.1