From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladislav Yasevich Subject: [PATCH 0/2] Fix issues with vlans without REORDER_HEADER Date: Mon, 16 Nov 2015 15:43:43 -0500 Message-ID: <1447706625-25979-1-git-send-email-vyasevic@redhat.com> Cc: phil@nwl.cc, kaber@trash.net, Vladislav Yasevich To: netdev@vger.kernel.org Return-path: Received: from mail-qg0-f45.google.com ([209.85.192.45]:35753 "EHLO mail-qg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751041AbbKPUnx (ORCPT ); Mon, 16 Nov 2015 15:43:53 -0500 Received: by qgec40 with SMTP id c40so58326759qge.2 for ; Mon, 16 Nov 2015 12:43:52 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: A while ago Phil Sutter brought up an issue with vlans without REORDER_HEADER and bridges. The problem was that if a vlan without REORDER_HEADER was a port in the bridge, the bridge ended up forwarding corrupted packets that still contained the vlan header. The same issue exists for bridge mode macvlan/macvtap devices. An additional issue with vlans without REORDER_HEADER is that stacking them also doesn't work. The reason here is that skb_reorder_vlan_header() function assumes that it on ETH_HLEN bytes deep into the packet. That is not the case, when you a vlan without REORRDER_HEADER flag set. This series attempts to correct these 2 issues. 1) To solve the stacked vlans problem, the patch simply use skb->mac_len as an offset to start copying mac addresses that is part of header reordering. 2) To fix the issue with bridge/macvlan/macvtap, the second patch simply doesn't write the vlan header back to the packet if the vlan device is either a bridge or a macvlan port. This ends up being the simplest and least performance intrussive solution. I've considered extending patch 2 to all stacked devices (essentially checked for the presense of rx_handler), but that feels like a broader restriction and _may_ break existing uses. Thanks -vlad Vladislav Yasevich (2): vlan: Fix untag operations of stacked vlans with REORDER_HEADER off vlan: Do not put vlan headers back on bridge and macvlan ports include/linux/netdevice.h | 5 +++++ net/8021q/vlan_core.c | 4 +++- net/core/skbuff.c | 3 ++- 3 files changed, 10 insertions(+), 2 deletions(-) -- 1.9.3