vti6: Add pmtu handling to vti6_xmit.

We currently rely on the PMTU discovery of xfrm.
However if a packet is localy sent, the PMTU mechanism
of xfrm tries to to local socket notification what
might not work for applications like ping that don't
check for this. So add pmtu handling to vti6_xmit to
report MTU changes immediately.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Steffen Klassert 2015-05-29 11:28:26 -07:00 committed by David S. Miller
parent 18ec898ee5
commit ccd740cbc6

View File

@ -435,6 +435,7 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
struct net_device *tdev;
struct xfrm_state *x;
int err = -1;
int mtu;
if (!dst)
goto tx_err_link_failure;
@ -468,6 +469,19 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
skb_dst_set(skb, dst);
skb->dev = skb_dst(skb)->dev;
mtu = dst_mtu(dst);
if (!skb->ignore_df && skb->len > mtu) {
skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu);
if (skb->protocol == htons(ETH_P_IPV6))
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
else
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
htonl(mtu));
return -EMSGSIZE;
}
err = dst_output(skb);
if (net_xmit_eval(err) == 0) {
struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);