vti6: fix PMTU caching and reporting on xmit

When setting the skb->dst before doing the MTU check, the route PMTU
caching and reporting is done on the new dst which is about to be
released.

Instead, PMTU handling should be done using the original dst.

This is aligned with IPv4 VTI.

Fixes: ccd740cbc6 ("vti6: Add pmtu handling to vti6_xmit.")
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This commit is contained in:
Eyal Birger 2018-06-07 10:11:02 +03:00 committed by Steffen Klassert
parent 1c8c5a9d38
commit d6990976af

View File

@ -480,10 +480,6 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
goto tx_err_dst_release;
}
skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
skb_dst_set(skb, dst);
skb->dev = skb_dst(skb)->dev;
mtu = dst_mtu(dst);
if (!skb->ignore_df && skb->len > mtu) {
skb_dst_update_pmtu(skb, mtu);
@ -498,9 +494,14 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
htonl(mtu));
}
return -EMSGSIZE;
err = -EMSGSIZE;
goto tx_err_dst_release;
}
skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
skb_dst_set(skb, dst);
skb->dev = skb_dst(skb)->dev;
err = dst_output(t->net, skb->sk, skb);
if (net_xmit_eval(err) == 0) {
struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);