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=-7.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 DFAF0C433E0 for ; Wed, 29 Jul 2020 00:24:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C02EA2078E for ; Wed, 29 Jul 2020 00:24:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730634AbgG2AYt (ORCPT ); Tue, 28 Jul 2020 20:24:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43188 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728236AbgG2AYt (ORCPT ); Tue, 28 Jul 2020 20:24:49 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2805BC061794; Tue, 28 Jul 2020 17:24:49 -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 0C1E0128D35D5; Tue, 28 Jul 2020 17:08:03 -0700 (PDT) Date: Tue, 28 Jul 2020 17:24:47 -0700 (PDT) Message-Id: <20200728.172447.1925120854282970312.davem@davemloft.net> To: xiyuyang19@fudan.edu.cn Cc: kuznet@ms2.inr.ac.ru, yoshfuji@linux-ipv6.org, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, tanxin.ctf@gmail.com Subject: Re: [PATCH] ipv6: Fix nexthop refcnt leak when creating ipv6 route info From: David Miller In-Reply-To: <1595664139-40703-1-git-send-email-xiyuyang19@fudan.edu.cn> References: <1595664139-40703-1-git-send-email-xiyuyang19@fudan.edu.cn> 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]); Tue, 28 Jul 2020 17:08:03 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiyu Yang Date: Sat, 25 Jul 2020 16:02:18 +0800 > ip6_route_info_create() invokes nexthop_get(), which increases the > refcount of the "nh". > > When ip6_route_info_create() returns, local variable "nh" becomes > invalid, so the refcount should be decreased to keep refcount balanced. > > The reference counting issue happens in one exception handling path of > ip6_route_info_create(). When nexthops can not be used with source > routing, the function forgets to decrease the refcnt increased by > nexthop_get(), causing a refcnt leak. > > Fix this issue by pulling up the error source routing handling when > nexthops can not be used with source routing. > > Signed-off-by: Xiyu Yang > Signed-off-by: Xin Tan Applied and queued up for -stable, thanks.