[SCTP]: Fix SCTP_SHUTDOWN notifications.

Fix to allow SCTP_SHUTDOWN notifications to be received on 1-1 style
SCTP SOCK_STREAM sockets.

Add SCTP_SHUTDOWN notification to the receive queue before updating
the state of the association.

Signed-off-by: Sridhar Samudrala <[e-mail]>
Signed-off-by: Neil Horman <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/sctp/sm_statefuns.c

···
 	skb_pull(chunk->skb, sizeof(sctp_shutdownhdr_t));
 	chunk->subh.shutdown_hdr = sdh;
 
+	/* API 5.3.1.5 SCTP_SHUTDOWN_EVENT
+	 * When a peer sends a SHUTDOWN, SCTP delivers this notification to
+	 * inform the application that it should cease sending data.
+	 */
+	ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC);
+	if (!ev) {
+		disposition = SCTP_DISPOSITION_NOMEM;
+		goto out;	
+	}
+	sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
+
 	/* Upon the reception of the SHUTDOWN, the peer endpoint shall
 	 *  - enter the SHUTDOWN-RECEIVED state,
 	 *  - stop accepting new data from its SCTP user
···
 	 */
 	sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN,
 			SCTP_U32(chunk->subh.shutdown_hdr->cum_tsn_ack));
-
-	/* API 5.3.1.5 SCTP_SHUTDOWN_EVENT
-	 * When a peer sends a SHUTDOWN, SCTP delivers this notification to
-	 * inform the application that it should cease sending data.
-	 */
-	ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC);
-	if (!ev) {
-		disposition = SCTP_DISPOSITION_NOMEM;
-		goto out;	
-	}
-	sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
 
 out:
 	return disposition;