From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD2C2C433FF for ; Mon, 29 Jul 2019 10:31:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D410206E0 for ; Mon, 29 Jul 2019 10:31:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728261AbfG2KbA (ORCPT ); Mon, 29 Jul 2019 06:31:00 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56960 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726358AbfG2KbA (ORCPT ); Mon, 29 Jul 2019 06:31:00 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 015CAC049E10; Mon, 29 Jul 2019 10:31:00 +0000 (UTC) Received: from localhost (unknown [10.40.205.71]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9D3E860623; Mon, 29 Jul 2019 10:30:57 +0000 (UTC) Date: Mon, 29 Jul 2019 12:30:55 +0200 From: Jiri Benc To: Jia-Ju Bai Cc: davem@davemloft.net, sbrivio@redhat.com, sd@queasysnail.net, liuhangbin@gmail.com, dsahern@gmail.com, natechancellor@gmail.com, tglx@linutronix.de, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net: geneve: Fix a possible null-pointer dereference in geneve_link_config() Message-ID: <20190729123055.5a7ba416@redhat.com> In-Reply-To: <20190729102611.2338-1-baijiaju1990@gmail.com> References: <20190729102611.2338-1-baijiaju1990@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Mon, 29 Jul 2019 10:31:00 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, 29 Jul 2019 18:26:11 +0800, Jia-Ju Bai wrote: > --- a/drivers/net/geneve.c > +++ b/drivers/net/geneve.c > @@ -1521,9 +1521,10 @@ static void geneve_link_config(struct net_device *dev, > rt = rt6_lookup(geneve->net, &info->key.u.ipv6.dst, NULL, 0, > NULL, 0); > > - if (rt && rt->dst.dev) > + if (rt && rt->dst.dev) { > ldev_mtu = rt->dst.dev->mtu - GENEVE_IPV6_HLEN; > - ip6_rt_put(rt); > + ip6_rt_put(rt); > + } > break; > } > #endif Are you sure rt6_lookup can never return a non-NULL rt with rt->dst.dev being NULL? You'd leak the reference in such case. Jiri