net: sctp: confirm route during forward progress
This fix has been proposed originally by Vlad Yasevich. He says:
When SCTP makes forward progress (receives a SACK that acks new chunks,
renegs, or answeres 0-window probes) or when HB-ACK arrives, mark
the route as confirmed so we don't unnecessarily send NUD probes.
Having a simple SCTP client/server that exchange data chunks every 1sec,
without this patch ARP requests are sent periodically every 40-60sec.
With this fix applied, an ARP request is only done once right at the
"session" beginning. Also, when clearing the related ARP cache entry
manually during the session, a new request is correctly done. I have
only "backported" this to net-next and tested that it works, so full
credit goes to Vlad.
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index cf6f845..9da6885 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -730,6 +730,12 @@
sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
SCTP_HEARTBEAT_SUCCESS);
+ /* HB-ACK was received for a the proper HB. Consider this
+ * forward progress.
+ */
+ if (t->dst)
+ dst_confirm(t->dst);
+
/* The receiver of the HEARTBEAT ACK should also perform an
* RTT measurement for that destination transport address
* using the time value carried in the HEARTBEAT ACK chunk.