From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: [Patch net] vxlan: use dev->needed_headroom instead of dev->hard_header_len Date: Thu, 12 Jun 2014 11:53:10 -0700 Message-ID: <1402599190-24350-1-git-send-email-xiyou.wangcong@gmail.com> Cc: "David S. Miller" , stephen hemminger , Pravin B Shelar , Cong Wang , Cong Wang To: netdev@vger.kernel.org Return-path: Received: from mail-pd0-f175.google.com ([209.85.192.175]:52954 "EHLO mail-pd0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750790AbaFLSxY (ORCPT ); Thu, 12 Jun 2014 14:53:24 -0400 Received: by mail-pd0-f175.google.com with SMTP id v10so367139pde.34 for ; Thu, 12 Jun 2014 11:53:23 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: From: Cong Wang When we mirror packets from a vxlan tunnel to other device, the mirror device should see the same packets (that is, without outer header). Because vxlan tunnel sets dev->hard_header_len, tcf_mirred() resets mac header back to outer mac, the mirror device actually sees packets with outer headers Vxlan tunnel should set dev->needed_headroom instead of dev->hard_header_len, like what other ip tunnels do. This fixes the above problem. Cc: "David S. Miller" Cc: stephen hemminger Cc: Pravin B Shelar Signed-off-by: Cong Wang Signed-off-by: Cong Wang --- diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 1610d51..e0995ff 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -2247,9 +2247,9 @@ static void vxlan_setup(struct net_device *dev) eth_hw_addr_random(dev); ether_setup(dev); if (vxlan->default_dst.remote_ip.sa.sa_family == AF_INET6) - dev->hard_header_len = ETH_HLEN + VXLAN6_HEADROOM; + dev->needed_headroom = ETH_HLEN + VXLAN6_HEADROOM; else - dev->hard_header_len = ETH_HLEN + VXLAN_HEADROOM; + dev->needed_headroom = ETH_HLEN + VXLAN_HEADROOM; dev->netdev_ops = &vxlan_netdev_ops; dev->destructor = free_netdev; @@ -2646,8 +2646,7 @@ static int vxlan_newlink(struct net *net, struct net_device *dev, if (!tb[IFLA_MTU]) dev->mtu = lowerdev->mtu - (use_ipv6 ? VXLAN6_HEADROOM : VXLAN_HEADROOM); - /* update header length based on lower device */ - dev->hard_header_len = lowerdev->hard_header_len + + dev->needed_headroom = lowerdev->hard_header_len + (use_ipv6 ? VXLAN6_HEADROOM : VXLAN_HEADROOM); } else if (use_ipv6) vxlan->flags |= VXLAN_F_IPV6;