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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D55A5C83004 for ; Tue, 28 Apr 2020 21:11:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB9F92072A for ; Tue, 28 Apr 2020 21:11:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726424AbgD1VLO (ORCPT ); Tue, 28 Apr 2020 17:11:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40592 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726284AbgD1VLN (ORCPT ); Tue, 28 Apr 2020 17:11:13 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0B28C03C1AC; Tue, 28 Apr 2020 14:11:13 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 99016120F52B8; Tue, 28 Apr 2020 14:11:12 -0700 (PDT) Date: Tue, 28 Apr 2020 14:11:11 -0700 (PDT) Message-Id: <20200428.141111.54288142814578996.davem@davemloft.net> To: yuehaibing@huawei.com Cc: andrew.hendry@gmail.com, kuba@kernel.org, allison@lohutok.net, tglx@linutronix.de, gregkh@linuxfoundation.org, tanxin.ctf@gmail.com, xiyuyang19@fudan.edu.cn, linux-x25@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net/x25: Fix null-ptr-deref in x25_disconnect From: David Miller In-Reply-To: <20200428081208.26308-1-yuehaibing@huawei.com> References: <000000000000cbf17205a452ad4f@google.com> <20200428081208.26308-1-yuehaibing@huawei.com> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 28 Apr 2020 14:11:13 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: YueHaibing Date: Tue, 28 Apr 2020 16:12:08 +0800 > We should check null before do x25_neigh_put in x25_disconnect, > otherwise may cause null-ptr-deref like this: ... > Reported-by: syzbot+6db548b615e5aeefdce2@syzkaller.appspotmail.com > Fixes: 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect") > Signed-off-by: YueHaibing Applied.