sctp: fix missing send up SCTP_SENDER_DRY_EVENT when subscribe it

[pandora-kernel.git] / net / sctp / socket.c

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 6766913..08c6238 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -2073,10 +2073,33 @@ static int sctp_setsockopt_disable_fragments(struct sock *sk,
 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
                                  unsigned int optlen)
 {
+       struct sctp_association *asoc;
+       struct sctp_ulpevent *event;
+
        if (optlen > sizeof(struct sctp_event_subscribe))
                return -EINVAL;
        if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
                return -EFAULT;
+
+       /*
+        * At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
+        * if there is no data to be sent or retransmit, the stack will
+        * immediately send up this notification.
+        */
+       if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
+                                      &sctp_sk(sk)->subscribe)) {
+               asoc = sctp_id2assoc(sk, 0);
+
+               if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
+                       event = sctp_ulpevent_make_sender_dry_event(asoc,
+                                       GFP_ATOMIC);
+                       if (!event)
+                               return -ENOMEM;
+
+                       sctp_ulpq_tail_event(&asoc->ulpq, event);
+               }
+       }
+
        return 0;
 }