[SCTP]: Do not timestamp every SCTP packet.

We only need the timestamp on COOKIE-ECHO chunks, so instead of always
timestamping every SCTP packet, let common code timestamp if the socket
option is set.  For COOKIE-ECHO, simply get the time of day if we don't
have a timestamp.  This introduces a small possibility that the cookie
may be considered expired, but it will be renegotiated.

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>

1 files changed, 9 insertions, 1 deletions

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 7745bdea7817..507dff72c585 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1447,8 +1447,16 @@ no_hmac:
         /* Check to see if the cookie is stale.  If there is already
          * an association, there is no need to check cookie's expiration
          * for init collision case of lost COOKIE ACK.
+         * If skb has been timestamped, then use the stamp, otherwise
+         * use current time.  This introduces a small possibility that
+         * that a cookie may be considered expired, but his would only slow
+         * down the new association establishment instead of every packet.
          */
-        skb_get_timestamp(skb, &tv);
+        if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
+                skb_get_timestamp(skb, &tv);
+        else
+                do_gettimeofday(&tv);
+
         if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
                 __u16 len;
                 /*