SCTP: Reset rtt_in_progress for the chunk when processing its sack.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

net/sctp/outqueue.c

@@ -1262,6 +1262,7 @@ static void sctp_check_transmitted(struct sctp_outq *q,
 			   	if (!tchunk->tsn_gap_acked &&
 				    !tchunk->resent &&
 				    tchunk->rtt_in_progress) {
+					tchunk->rtt_in_progress = 0;
 					rtt = jiffies - tchunk->sent_at;
 					sctp_transport_update_rto(transport,
 								  rtt);