From 4c38255892c06b9de2fb3bf6aea63f4ebdff3d11 Mon Sep 17 00:00:00 2001 From: Eyal Birger Date: Fri, 26 Feb 2021 23:35:06 +0200 Subject: vti6: fix ipv4 pmtu check to honor ip header df Frag needed should only be sent if the header enables DF. This fix allows IPv4 packets larger than MTU to pass the vti6 interface and be fragmented after encapsulation, aligning behavior with non-vti6 xfrm. Fixes: ccd740cbc6e0 ("vti6: Add pmtu handling to vti6_xmit.") Signed-off-by: Eyal Birger Reviewed-by: Sabrina Dubroca Signed-off-by: Steffen Klassert --- net/ipv6/ip6_vti.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net/ipv6/ip6_vti.c') diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c index 0225fd694192..2f0be5ac021c 100644 --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -494,7 +494,7 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) } if (dst->flags & DST_XFRM_QUEUE) - goto queued; + goto xmit; x = dst->xfrm; if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr)) @@ -523,6 +523,8 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); } else { + if (!(ip_hdr(skb)->frag_off & htons(IP_DF))) + goto xmit; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); } @@ -531,7 +533,7 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) goto tx_err_dst_release; } -queued: +xmit: skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); skb_dst_set(skb, dst); skb->dev = skb_dst(skb)->dev; -- cgit v1.2.3