ipv6: support IPV6_PMTU_INTERFACE on sockets

IPV6_PMTU_INTERFACE is the same as IPV6_PMTU_PROBE for ipv6. Add it
nontheless for symmetry with IPv4 sockets. Also drop incoming MTU
information if this mode is enabled.

The additional bit in ipv6_pinfo just eats in the padding behind the
bitfield. There are no changes to the layout of the struct at all.

Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/net/sctp/input.c b/net/sctp/input.c
index 2a192a7c5d81..042ec6c9ae24 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -389,6 +389,9 @@ void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc,
         if (!t || (t->pathmtu <= pmtu))
                 return;
 
+        if (!ip6_sk_accept_pmtu(sk))
+                return;
+
         if (sock_owned_by_user(sk)) {
                 asoc->pmtu_pending = 1;
                 t->pmtu_pending = 1;