From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexei Starovoitov Subject: Re: [PATCH net] skbuff: Fix skb checksum flag on skb pull Date: Mon, 31 Aug 2015 18:40:25 -0700 Message-ID: <20150901014022.GA11983@Alexeis-MacBook-Pro-2.local> References: <1441061746-1492-1-git-send-email-pshelar@nicira.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org To: Pravin B Shelar Return-path: Received: from mail-io0-f173.google.com ([209.85.223.173]:36368 "EHLO mail-io0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754412AbbIABk2 (ORCPT ); Mon, 31 Aug 2015 21:40:28 -0400 Received: by iod35 with SMTP id 35so49240766iod.3 for ; Mon, 31 Aug 2015 18:40:27 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1441061746-1492-1-git-send-email-pshelar@nicira.com> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Aug 31, 2015 at 03:55:46PM -0700, Pravin B Shelar wrote: > VXLAN device can receive skb with checksum partial. But the checksum > offset could be in outer header which is pulled on receive. Such skb > can cause the panic when checksum is calculated on skb. Following patch > fixes the bug by setting checksum unnecessary while pulling outer header. > > ---8<--- > [ 13.800141] RIP: 0010:[] [] skb_checksum_help+0x144/0x150 > [ 13.800141] RSP: 0000:ffff88011fd83940 EFLAGS: 00010292 > [ 13.800141] RAX: 0000000000000042 RBX: ffff880114dd56c0 RCX: ffff8801188d9580 > ... > ... > [ 13.852308] Call Trace: > [ 13.852308] > [ 13.852308] [] queue_userspace_packet+0x408/0x470 [openvswitch] > [ 13.852308] [] ovs_dp_upcall+0x5d/0x60 [openvswitch] > [ 13.852308] [] ovs_dp_process_packet_with_key+0xe6/0x100 [openvswitch] > [ 13.852308] [] ovs_dp_process_received_packet+0x4b/0x80 [openvswitch] that doesn't look like upstream kernel. The above two functions don't exist in net-next.