From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philip Prindeville Subject: Re: [PATCH net-next] net: ipv4: Add ability to have GRE ignore DF bit in IPv4 payloads Date: Tue, 7 Jun 2016 14:42:16 -0600 Message-ID: <575731A8.1040303@redfish-solutions.com> References: <20160607194846.11494-1-philipp@redfish-solutions.com> <1465331022.134529.630880921.787BED73@webmail.messagingengine.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: Stephen Hemminger To: Hannes Frederic Sowa , netdev@vger.kernel.org Return-path: Received: from mail.redfish-solutions.com ([66.232.79.143]:54896 "EHLO mail.redfish-solutions.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756598AbcFGUmZ (ORCPT ); Tue, 7 Jun 2016 16:42:25 -0400 In-Reply-To: <1465331022.134529.630880921.787BED73@webmail.messagingengine.com> Sender: netdev-owner@vger.kernel.org List-ID: On 06/07/2016 02:23 PM, Hannes Frederic Sowa wrote: > > On Tue, Jun 7, 2016, at 21:48, Philip Prindeville wrote: >> static struct rtnl_link_ops ipgre_link_ops __read_mostly = { >> diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c >> index d8f5e0a..95649eb 100644 >> --- a/net/ipv4/ip_tunnel.c >> +++ b/net/ipv4/ip_tunnel.c >> @@ -682,7 +682,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct >> net_device *dev, >> } >> >> df = tnl_params->frag_off; >> - if (skb->protocol == htons(ETH_P_IP)) >> + if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df) >> df |= (inner_iph->frag_off&htons(IP_DF)); >> >> max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) > Is still enforce that we inherit the ttl from the inner header to the > outer header if we don't set df bit? > > Thanks, > Hannes That's correct. That happens a few lines above and we don't change that behavior with this patch. -Philip