From patchwork Tue May 23 22:13:47 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 9744387 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id CAB056032B for ; Tue, 23 May 2017 22:38:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BE6E728858 for ; Tue, 23 May 2017 22:38:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B37C52885E; Tue, 23 May 2017 22:38:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5E21E28858 for ; Tue, 23 May 2017 22:38:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765240AbdEWWiA (ORCPT ); Tue, 23 May 2017 18:38:00 -0400 Received: from gateway32.websitewelcome.com ([192.185.145.182]:42080 "EHLO gateway32.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757598AbdEWWh6 (ORCPT ); Tue, 23 May 2017 18:37:58 -0400 X-Greylist: delayed 1371 seconds by postgrey-1.27 at vger.kernel.org; Tue, 23 May 2017 18:37:58 EDT Received: from cm2.websitewelcome.com (cm2.websitewelcome.com [192.185.178.13]) by gateway32.websitewelcome.com (Postfix) with ESMTP id C421186F361 for ; Tue, 23 May 2017 17:13:49 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cm2.websitewelcome.com with id PyDo1v00h0V9LXg01yDpZT; Tue, 23 May 2017 17:13:49 -0500 Received: from [189.152.160.17] (port=42786 helo=embeddedgus) by gator4166.hostgator.com with esmtpa (Exim 4.87) (envelope-from ) id 1dDI3o-000OFN-Iz; Tue, 23 May 2017 17:13:48 -0500 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-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: 2 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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) {