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=-4.0 required=3.0 tests=BAYES_00, 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 987E1C433DF for ; Mon, 27 Jul 2020 18:39:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 833BE2078E for ; Mon, 27 Jul 2020 18:39:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730915AbgG0SjS (ORCPT ); Mon, 27 Jul 2020 14:39:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728464AbgG0SjS (ORCPT ); Mon, 27 Jul 2020 14:39:18 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2154DC061794; Mon, 27 Jul 2020 11:39:18 -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 4388A11DB3142; Mon, 27 Jul 2020 11:22:32 -0700 (PDT) Date: Mon, 27 Jul 2020 11:39:16 -0700 (PDT) Message-Id: <20200727.113916.2247175777216104943.davem@davemloft.net> To: gaurav1086@gmail.com Cc: kuznet@ms2.inr.ac.ru, yoshfuji@linux-ipv6.org, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [net/ipv6] ip6_output: Add ipv6_pinfo null check From: David Miller In-Reply-To: <20200727033810.28883-1-gaurav1086@gmail.com> References: <20200727033810.28883-1-gaurav1086@gmail.com> X-Mailer: Mew version 6.8 on Emacs 26.3 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]); Mon, 27 Jul 2020 11:22:32 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Gaurav Singh Date: Sun, 26 Jul 2020 23:38:10 -0400 > ipv6_pinfo is initlialized by inet6_sk() which returns NULL. > Hence it can cause segmentation fault. Fix this by adding a > NULL check. Please take your time with such changes and actually look at the compiler output, it will warn that you are adding a new problem. Specifically, the function now fails to return a value at all. But even more important, how is the situation you are fixing possible? Do you have a sample crash? Can you please describe the code paths and conditions that lead to the problem? You must also provide a valid and properly formatted Fixes: tag for bug fixes such as this. Thank you.