From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net] netvsc: fix incorrect receive checksum offloading Date: Wed, 26 Oct 2016 23:19:42 -0400 (EDT) Message-ID: <20161026.231942.1795915733192661471.davem@davemloft.net> References: <20161023213247.75d43c48@xeon-e3> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: kys@microsoft.com, haiyangz@microsoft.com, netdev@vger.kernel.org To: stephen@networkplumber.org Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:45550 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752855AbcJ0DTo (ORCPT ); Wed, 26 Oct 2016 23:19:44 -0400 In-Reply-To: <20161023213247.75d43c48@xeon-e3> Sender: netdev-owner@vger.kernel.org List-ID: From: Stephen Hemminger Date: Sun, 23 Oct 2016 21:32:47 -0700 > From: Stephen Hemminger > > The Hyper-V netvsc driver was looking at the incorrect status bits > in the checksum info. It was setting the receive checksum unnecessary > flag based on the IP header checksum being correct. The checksum > flag is skb is about TCP and UDP checksum status. Because of this > bug, any packet received with bad TCP checksum would be passed > up the stack and to the application causing data corruption. > The problem is reproducible via netcat and netem. > > This had a side effect of not doing receive checksum offload > on IPv6. The driver was also also always doing checksum offload > independent of the checksum setting done via ethtool. > > Signed-off-by: Stephen Hemminger Applied and queued up for -stable.