From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765118AbdEWWh6 (ORCPT ); Tue, 23 May 2017 18:37:58 -0400 Received: from gateway20.websitewelcome.com ([192.185.68.24]:32968 "EHLO gateway20.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757598AbdEWWhu (ORCPT ); Tue, 23 May 2017 18:37:50 -0400 X-Greylist: delayed 1377 seconds by postgrey-1.27 at vger.kernel.org; Tue, 23 May 2017 18:37:50 EDT Date: Tue, 23 May 2017 17:13:47 -0500 From: "Gustavo A. R. Silva" To: Josef Bacik Cc: linux-block@vger.kernel.org, nbd-general@lists.sourceforge.net, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] block: fix potential null pointer dereference Message-ID: <20170523221347.GA11184@embeddedgus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.152.160.17 X-Exim-ID: 1dDI3o-000OFN-Iz X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedgus) [189.152.160.17]:42786 X-Source-Auth: garsilva@embeddedor.com X-Email-Count: 4 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add null check before dereferencing pointer dev_list inside function nla_nest_end() at line 1968: nla_nest_end(reply, dev_list); Addresses-Coverity-ID: 1408827 Signed-off-by: Gustavo A. R. Silva --- drivers/block/nbd.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 9a7bb2c..6006de5 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1948,6 +1948,9 @@ static int nbd_genl_status(struct sk_buff *skb, struct genl_info *info) } dev_list = nla_nest_start(reply, NBD_ATTR_DEVICE_LIST); + if (!dev_list) + goto out; + if (index == -1) { ret = idr_for_each(&nbd_index_idr, &status_cb, reply); if (ret) { -- 2.5.0