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=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham 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 8FD51C282D7 for ; Wed, 30 Jan 2019 23:25:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 49FA120882 for ; Wed, 30 Jan 2019 23:25:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727056AbfA3XY7 (ORCPT ); Wed, 30 Jan 2019 18:24:59 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:52410 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725768AbfA3XY6 (ORCPT ); Wed, 30 Jan 2019 18:24:58 -0500 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::bf5]) (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 8B38F14F46E8E; Wed, 30 Jan 2019 14:06:48 -0800 (PST) Date: Wed, 30 Jan 2019 14:06:48 -0800 (PST) Message-Id: <20190130.140648.324657429617438176.davem@davemloft.net> To: yohei.kanemaru@gmail.com Cc: netdev@vger.kernel.org, dlebrun@google.com Subject: Re: [PATCH net] ipv6: sr: clear IP6CB(skb) on SRH ip4ip6 encapsulation From: David Miller In-Reply-To: <20190129065234.68121-1-yohei.kanemaru@gmail.com> References: <20190129065234.68121-1-yohei.kanemaru@gmail.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]); Wed, 30 Jan 2019 14:06:48 -0800 (PST) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Yohei Kanemaru Date: Tue, 29 Jan 2019 15:52:34 +0900 > skb->cb may contain data from previous layers (in an observed case > IPv4 with L3 Master Device). In the observed scenario, the data in > IPCB(skb)->frags was misinterpreted as IP6CB(skb)->frag_max_size, > eventually caused an unexpected IPv6 fragmentation in ip6_fragment() > through ip6_finish_output(). > > This patch clears IP6CB(skb), which potentially contains garbage data, > on the SRH ip4ip6 encapsulation. > > Fixes: 32d99d0b6702 ("ipv6: sr: add support for ip4ip6 encapsulation") > Signed-off-by: Yohei Kanemaru Applied, thanks.