sctp: Correclty set changeover_active for SFR-CACC

Right now, any time we set a primary transport we set
the changeover_active flag.  As a result, we invoke SFR-CACC
even when there has been no changeover events.

Only set changeover_active, when there is a true changeover
event, i.e. we had a primary path and we are changing to
another transport.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 2 deletions

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 532634861db1..024c3ebd9661 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -474,6 +474,15 @@ static void sctp_association_destroy(struct sctp_association *asoc)
 void sctp_assoc_set_primary(struct sctp_association *asoc,
                             struct sctp_transport *transport)
 {
+        int changeover = 0;
+
+        /* it's a changeover only if we already have a primary path
+         * that we are changing
+         */
+        if (asoc->peer.primary_path != NULL &&
+            asoc->peer.primary_path != transport)
+                changeover = 1 ;
+
         asoc->peer.primary_path = transport;
 
         /* Set a default msg_name for events. */
@@ -499,12 +508,12 @@ void sctp_assoc_set_primary(struct sctp_association *asoc,
          * double switch to the same destination address.
          */
         if (transport->cacc.changeover_active)
-                transport->cacc.cycling_changeover = 1;
+                transport->cacc.cycling_changeover = changeover;
 
         /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
          * a changeover has occurred.
          */
-        transport->cacc.changeover_active = 1;
+        transport->cacc.changeover_active = changeover;
 
         /* 3) The sender MUST store the next TSN to be sent in
          * next_tsn_at_change.