From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=K4f4=Q4=vger.kernel.org=netdev-owner@kernel.org>
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 AE0FEC43381
	for <netdev@archiver.kernel.org>; Thu, 21 Feb 2019 22:08:52 +0000 (UTC)
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by mail.kernel.org (Postfix) with ESMTP id 83864207E0
	for <netdev@archiver.kernel.org>; Thu, 21 Feb 2019 22:08:52 +0000 (UTC)
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1726869AbfBUWIv (ORCPT <rfc822;netdev@archiver.kernel.org>);
        Thu, 21 Feb 2019 17:08:51 -0500
Received: from shards.monkeyblade.net ([23.128.96.9]:43756 "EHLO
        shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1726035AbfBUWIv (ORCPT
        <rfc822;netdev@vger.kernel.org>); Thu, 21 Feb 2019 17:08:51 -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 8D14A1462EC31;
        Thu, 21 Feb 2019 14:08:50 -0800 (PST)
Date:   Thu, 21 Feb 2019 14:08:49 -0800 (PST)
Message-Id: <20190221.140849.2117139861357774917.davem@davemloft.net>
To:     willemdebruijn.kernel@gmail.com
Cc:     netdev@vger.kernel.org, willemb@google.com
Subject: Re: [PATCH net] net: avoid false positives in untrusted gso
 validation
From:   David Miller <davem@davemloft.net>
In-Reply-To: <20190219043712.97121-1-willemdebruijn.kernel@gmail.com>
References: <20190219043712.97121-1-willemdebruijn.kernel@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]); Thu, 21 Feb 2019 14:08:50 -0800 (PST)
Sender: netdev-owner@vger.kernel.org
Precedence: bulk
List-ID: <netdev.vger.kernel.org>
X-Mailing-List: netdev@vger.kernel.org

From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Date: Mon, 18 Feb 2019 23:37:12 -0500

> From: Willem de Bruijn <willemb@google.com>
> 
> GSO packets with vnet_hdr must conform to a small set of gso_types.
> The below commit uses flow dissection to drop packets that do not.
> 
> But it has false positives when the skb is not fully initialized.
> Dissection needs skb->protocol and skb->network_header.
> 
> Infer skb->protocol from gso_type as the two must agree.
> SKB_GSO_UDP can use both ipv4 and ipv6, so try both.
> 
> Exclude callers for which network header offset is not known.
> 
> Fixes: d5be7f632bad ("net: validate untrusted gso packets without csum offload")
> Signed-off-by: Willem de Bruijn <willemb@google.com>

Applied and queued up for -stable, thanks.