From d669bd62756ff89c3d49fc9e23973087ea27dfdd Mon Sep 17 00:00:00 2001 From: Alexey Kodanev Date: Thu, 23 Aug 2018 19:49:54 +0300 Subject: [PATCH] vti6: remove !skb->ignore_df check from vti6_xmit() [ Upstream commit 9f2895461439fda2801a7906fb4c5fb3dbb37a0a ] Before the commit d6990976af7c ("vti6: fix PMTU caching and reporting on xmit") '!skb->ignore_df' check was always true because the function skb_scrub_packet() was called before it, resetting ignore_df to zero. In the commit, skb_scrub_packet() was moved below, and now this check can be false for the packet, e.g. when sending it in the two fragments, this prevents successful PMTU updates in such case. The next attempts to send the packet lead to the same tx error. Moreover, vti6 initial MTU value relies on PMTU adjustments. This issue can be reproduced with the following LTP test script: udp_ipsec_vti.sh -6 -p ah -m tunnel -s 2000 Fixes: ccd740cbc6e0 ("vti6: Add pmtu handling to vti6_xmit.") Signed-off-by: Alexey Kodanev Acked-by: Steffen Klassert Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_vti.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c index a5aeeb613fac..3213921cdfee 100644 --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -481,7 +481,7 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) } mtu = dst_mtu(dst); - if (!skb->ignore_df && skb->len > mtu) { + if (skb->len > mtu) { skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu); if (skb->protocol == htons(ETH_P_IPV6)) { -- 2.20.1