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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 91FCBC43381 for ; Mon, 11 Jan 2021 13:10:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6254D22B51 for ; Mon, 11 Jan 2021 13:10:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730860AbhAKNJ6 (ORCPT ); Mon, 11 Jan 2021 08:09:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:55254 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731075AbhAKNIw (ORCPT ); Mon, 11 Jan 2021 08:08:52 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0ACCE22B51; Mon, 11 Jan 2021 13:08:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610370516; bh=OgqyEGXjyUvFKj//u5k0NdHDA5+4FIBB1WfgxIWBzGU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jp0/fn+vQcvAUu3eJRo4/oGQVPYpk7kUkjWwxTepsO4mbH156kTA4itRdCxQvNlOS XZaGJQ3uRKpxjo1RwjQ+Oq8EqS7uKNkC78SuvI4e3MW0n6mq7lF71ZpDiKFL0TYfJ/ tAhxXVmIieCO3EfEVYONWXEMrS7iwZDp/Ru/JxhA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+f583ce3d4ddf9836b27a@syzkaller.appspotmail.com, William Tu , Lorenzo Bianconi , Cong Wang , "David S. Miller" Subject: [PATCH 4.19 29/77] erspan: fix version 1 check in gre_parse_header() Date: Mon, 11 Jan 2021 14:01:38 +0100 Message-Id: <20210111130037.802035875@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210111130036.414620026@linuxfoundation.org> References: <20210111130036.414620026@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Cong Wang [ Upstream commit 085c7c4e1c0e50d90b7d90f61a12e12b317a91e2 ] Both version 0 and version 1 use ETH_P_ERSPAN, but version 0 does not have an erspan header. So the check in gre_parse_header() is wrong, we have to distinguish version 1 from version 0. We can just check the gre header length like is_erspan_type1(). Fixes: cb73ee40b1b3 ("net: ip_gre: use erspan key field for tunnel lookup") Reported-by: syzbot+f583ce3d4ddf9836b27a@syzkaller.appspotmail.com Cc: William Tu Cc: Lorenzo Bianconi Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/gre_demux.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/ipv4/gre_demux.c +++ b/net/ipv4/gre_demux.c @@ -133,7 +133,7 @@ int gre_parse_header(struct sk_buff *skb * to 0 and sets the configured key in the * inner erspan header field */ - if (greh->protocol == htons(ETH_P_ERSPAN) || + if ((greh->protocol == htons(ETH_P_ERSPAN) && hdr_len != 4) || greh->protocol == htons(ETH_P_ERSPAN2)) { struct erspan_base_hdr *ershdr;