From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] vti6: remove !skb->ignore_df check from vti6_xmit()
Date: Wed, 29 Aug 2018 17:52:00 -0700 (PDT)
Message-ID: <20180829.175200.1127078582090340173.davem@davemloft.net>
References: <1535042994-27225-1-git-send-email-alexey.kodanev@oracle.com>
Mime-Version: 1.0
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Cc: netdev@vger.kernel.org, steffen.klassert@secunet.com
To: alexey.kodanev@oracle.com
Return-path: <netdev-owner@vger.kernel.org>
Received: from shards.monkeyblade.net ([23.128.96.9]:39078 "EHLO
        shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1725768AbeH3Evb (ORCPT
        <rfc822;netdev@vger.kernel.org>); Thu, 30 Aug 2018 00:51:31 -0400
In-Reply-To: <1535042994-27225-1-git-send-email-alexey.kodanev@oracle.com>
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

From: Alexey Kodanev <alexey.kodanev@oracle.com>
Date: Thu, 23 Aug 2018 19:49:54 +0300

> Before the commit d6990976af7c ("vti6: fix PMTU caching and reporting
> on xmit") '!skb->ignore_df' check was always true because the function
> skb_scrub_packet() was called before it, resetting ignore_df to zero.
> 
> In the commit, skb_scrub_packet() was moved below, and now this check
> can be false for the packet, e.g. when sending it in the two fragments,
> this prevents successful PMTU updates in such case. The next attempts
> to send the packet lead to the same tx error. Moreover, vti6 initial
> MTU value relies on PMTU adjustments.
> 
> This issue can be reproduced with the following LTP test script:
>     udp_ipsec_vti.sh -6 -p ah -m tunnel -s 2000
> 
> Fixes: ccd740cbc6e0 ("vti6: Add pmtu handling to vti6_xmit.")
> Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>

Applied and queued up for -stable, thank you.