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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 D1A0AC432BE for ; Thu, 29 Jul 2021 07:24:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B8B0660ED4 for ; Thu, 29 Jul 2021 07:24:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234666AbhG2HYd (ORCPT ); Thu, 29 Jul 2021 03:24:33 -0400 Received: from mail.netfilter.org ([217.70.188.207]:40442 "EHLO mail.netfilter.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234634AbhG2HYc (ORCPT ); Thu, 29 Jul 2021 03:24:32 -0400 Received: from netfilter.org (bl11-146-165.dsl.telepac.pt [85.244.146.165]) by mail.netfilter.org (Postfix) with ESMTPSA id E8DA86411D; Thu, 29 Jul 2021 09:23:56 +0200 (CEST) Date: Thu, 29 Jul 2021 09:24:20 +0200 From: Pablo Neira Ayuso To: yajun.deng@linux.dev Cc: kadlec@netfilter.org, fw@strlen.de, roopa@nvidia.com, nikolay@nvidia.com, davem@davemloft.net, kuba@kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, bridge@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] netfilter: nf_conntrack_bridge: Fix not free when error Message-ID: <20210729072420.GA16265@salvia> References: <20210728161849.GA10433@salvia> <20210726035702.11964-1-yajun.deng@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 29, 2021 at 03:19:01AM +0000, yajun.deng@linux.dev wrote: > July 29, 2021 12:18 AM, "Pablo Neira Ayuso" wrote: > > > On Mon, Jul 26, 2021 at 11:57:02AM +0800, Yajun Deng wrote: > > > >> It should be added kfree_skb_list() when err is not equal to zero > >> in nf_br_ip_fragment(). > >> > >> Fixes: 3c171f496ef5 ("netfilter: bridge: add connection tracking system") > >> Signed-off-by: Yajun Deng > >> --- > >> net/bridge/netfilter/nf_conntrack_bridge.c | 12 ++++++++---- > >> 1 file changed, 8 insertions(+), 4 deletions(-) > >> > >> diff --git a/net/bridge/netfilter/nf_conntrack_bridge.c > >> b/net/bridge/netfilter/nf_conntrack_bridge.c > >> index 8d033a75a766..059f53903eda 100644 > >> --- a/net/bridge/netfilter/nf_conntrack_bridge.c > >> +++ b/net/bridge/netfilter/nf_conntrack_bridge.c > >> @@ -83,12 +83,16 @@ static int nf_br_ip_fragment(struct net *net, struct sock *sk, > >> > >> skb->tstamp = tstamp; > >> err = output(net, sk, data, skb); > >> - if (err || !iter.frag) > >> - break; > >> - > >> + if (err) { > >> + kfree_skb_list(iter.frag); > >> + return err; > >> + } > >> + > >> + if (!iter.frag) > >> + return 0; > >> + > >> skb = ip_fraglist_next(&iter); > >> } > >> - return err; > > > > Why removing this line above? It enters slow_path: on success. > > > I used return rather than break, it wouldn't enter the slow_path. Right, your patch is correct. > > This patch instead will keep this aligned with IPv6. > > > I think err and !iter.frag are not related, there is no need to put > them in an if statement, We still need to separate them after loop. > So I separate them in loop and use return instead of break. In > addition, if you insist, I will accept your patch. Thanks. Yes, I'd prefer to keep it consistent with existing users of the fragment iterator, see: net/ipv4/ip_output.c net/ipv6/netfilter.c net/ipv6/ip6_output.c they are roughly using the same programming idiom to iterate over the fragments. Would you send a v2?