From c7c1abfd6d42be8f09d390ab912cd84983000fa2 Mon Sep 17 00:00:00 2001 From: Eyal Birger Date: Fri, 26 Feb 2021 23:35:05 +0200 Subject: vti: fix ipv4 pmtu check to honor ip header df Frag needed should only be sent if the header enables DF. This fix allows packets larger than MTU to pass the vti interface and be fragmented after encapsulation, aligning behavior with non-vti xfrm. Fixes: d6af1a31cc72 ("vti: Add pmtu handling to vti_xmit.") Signed-off-by: Eyal Birger Reviewed-by: Sabrina Dubroca Signed-off-by: Steffen Klassert --- net/ipv4/ip_vti.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net/ipv4/ip_vti.c') diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c index abc171e79d3e..613741384490 100644 --- a/net/ipv4/ip_vti.c +++ b/net/ipv4/ip_vti.c @@ -218,7 +218,7 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev, } if (dst->flags & DST_XFRM_QUEUE) - goto queued; + goto xmit; if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) { dev->stats.tx_carrier_errors++; @@ -238,6 +238,8 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev, if (skb->len > mtu) { skb_dst_update_pmtu_no_confirm(skb, mtu); if (skb->protocol == htons(ETH_P_IP)) { + if (!(ip_hdr(skb)->frag_off & htons(IP_DF))) + goto xmit; icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); } else { @@ -251,7 +253,7 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev, goto tx_error; } -queued: +xmit: skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); skb_dst_set(skb, dst); skb->dev = skb_dst(skb)->dev; -- cgit v1.2.3