xfrm: revert ipv4 mtu determination to dst_mtu
In commit 0ea9d5e3e0e03a63b11392f5613378977dae7eca ("xfrm: introduce
helper for safe determination of mtu") I switched the determination of
ipv4 mtus from dst_mtu to ip_skb_dst_mtu. This was an error because in
case of IP_PMTUDISC_PROBE we fall back to the interface mtu, which is
never correct for ipv4 ipsec.
This patch partly reverts 0ea9d5e3e0e03a63b11392f5613378977dae7eca
("xfrm: introduce helper for safe determination of mtu").
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index e092e30..6cd625e 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -140,10 +140,12 @@
{
struct dst_entry *dst = skb_dst(skb);
struct xfrm_state *x = dst->xfrm;
- int mtu = xfrm_skb_dst_mtu(skb);
+ int mtu;
- if (mtu < IPV6_MIN_MTU)
- mtu = IPV6_MIN_MTU;
+ if (skb->protocol == htons(ETH_P_IPV6))
+ mtu = ip6_skb_dst_mtu(skb);
+ else
+ mtu = dst_mtu(skb_dst(skb));
if (skb->len > mtu && xfrm6_local_dontfrag(skb)) {
xfrm6_local_rxpmtu(skb, mtu);