[SCTP] Flag a pmtu change request
Currently, if the socket is owned by the user, we drop the ICMP
message. As a result SCTP forgets that path MTU changed and
never adjusting it's estimate. This causes all subsequent
packets to be fragmented. With this patch, we'll flag the association
that it needs to udpate it's estimate based on the already updated
routing information.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index df94e3c..498edb0 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -1231,6 +1231,10 @@
/* Get the lowest pmtu of all the transports. */
list_for_each(pos, &asoc->peer.transport_addr_list) {
t = list_entry(pos, struct sctp_transport, transports);
+ if (t->pmtu_pending && t->dst) {
+ sctp_transport_update_pmtu(t, dst_mtu(t->dst));
+ t->pmtu_pending = 0;
+ }
if (!pmtu || (t->pathmtu < pmtu))
pmtu = t->pathmtu;
}
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 45d6a64..d57ff7f 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -367,9 +367,15 @@
void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc,
struct sctp_transport *t, __u32 pmtu)
{
- if (sock_owned_by_user(sk) || !t || (t->pathmtu == pmtu))
+ if (!t || (t->pathmtu == pmtu))
return;
+ if (sock_owned_by_user(sk)) {
+ asoc->pmtu_pending = 1;
+ t->pmtu_pending = 1;
+ return;
+ }
+
if (t->param_flags & SPP_PMTUD_ENABLE) {
/* Update transports view of the MTU */
sctp_transport_update_pmtu(t, pmtu);
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 45510c4..6edaaa0 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1662,6 +1662,9 @@
goto out_free;
}
+ if (asoc->pmtu_pending)
+ sctp_assoc_pending_pmtu(asoc);
+
/* If fragmentation is disabled and the message length exceeds the
* association fragmentation point, return EMSGSIZE. The I-D
* does not specify what this error is, but this looks like