1 files changed, 74 insertions, 29 deletions

diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c
index b29e3e4b72c..ac80c34f6c2 100644
--- a/net/sctp/ulpqueue.c
+++ b/net/sctp/ulpqueue.c
@@ -138,18 +138,42 @@ int sctp_ulpq_tail_data(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk,
 /* Clear the partial delivery mode for this socket.   Note: This
  * assumes that no association is currently in partial delivery mode.
  */
-int sctp_clear_pd(struct sock *sk)
+int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc)
 {
 	struct sctp_sock *sp = sctp_sk(sk);
 
-	sp->pd_mode = 0;
-	if (!skb_queue_empty(&sp->pd_lobby)) {
-		struct list_head *list;
-		sctp_skb_list_tail(&sp->pd_lobby, &sk->sk_receive_queue);
-		list = (struct list_head *)&sctp_sk(sk)->pd_lobby;
-		INIT_LIST_HEAD(list);
-		return 1;
+	if (atomic_dec_and_test(&sp->pd_mode)) {
+		/* This means there are no other associations in PD, so
+		 * we can go ahead and clear out the lobby in one shot
+		 */
+		if (!skb_queue_empty(&sp->pd_lobby)) {
+			struct list_head *list;
+			sctp_skb_list_tail(&sp->pd_lobby, &sk->sk_receive_queue);
+			list = (struct list_head *)&sctp_sk(sk)->pd_lobby;
+			INIT_LIST_HEAD(list);
+			return 1;
+		}
+	} else {
+		/* There are other associations in PD, so we only need to
+		 * pull stuff out of the lobby that belongs to the
+		 * associations that is exiting PD (all of its notifications
+		 * are posted here).
+		 */
+		if (!skb_queue_empty(&sp->pd_lobby) && asoc) {
+			struct sk_buff *skb, *tmp;
+			struct sctp_ulpevent *event;
+
+			sctp_skb_for_each(skb, &sp->pd_lobby, tmp) {
+				event = sctp_skb2event(skb);
+				if (event->asoc == asoc) {
+					__skb_unlink(skb, &sp->pd_lobby);
+					__skb_queue_tail(&sk->sk_receive_queue,
+							 skb);
+				}
+			}
+		}
 	}
+
 	return 0;
 }
 
@@ -157,7 +181,7 @@ int sctp_clear_pd(struct sock *sk)
 static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq)
 {
 	ulpq->pd_mode = 0;
-	return sctp_clear_pd(ulpq->asoc->base.sk);
+	return sctp_clear_pd(ulpq->asoc->base.sk, ulpq->asoc);
 }
 
 /* If the SKB of 'event' is on a list, it is the first such member
@@ -187,25 +211,35 @@ int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
 	 * the association the cause of the partial delivery.
 	 */
 
-	if (!sctp_sk(sk)->pd_mode) {
+	if (atomic_read(&sctp_sk(sk)->pd_mode) == 0) {
 		queue = &sk->sk_receive_queue;
-	} else if (ulpq->pd_mode) {
-		/* If the association is in partial delivery, we
-		 * need to finish delivering the partially processed
-		 * packet before passing any other data.  This is
-		 * because we don't truly support stream interleaving.
-		 */
-		if ((event->msg_flags & MSG_NOTIFICATION) ||
-		    (SCTP_DATA_NOT_FRAG ==
-			    (event->msg_flags & SCTP_DATA_FRAG_MASK)))
-			queue = &sctp_sk(sk)->pd_lobby;
-		else {
-			clear_pd = event->msg_flags & MSG_EOR;
-			queue = &sk->sk_receive_queue;
+	} else {
+		if (ulpq->pd_mode) {
+			/* If the association is in partial delivery, we
+			 * need to finish delivering the partially processed
+			 * packet before passing any other data.  This is
+			 * because we don't truly support stream interleaving.
+			 */
+			if ((event->msg_flags & MSG_NOTIFICATION) ||
+			    (SCTP_DATA_NOT_FRAG ==
+				    (event->msg_flags & SCTP_DATA_FRAG_MASK)))
+				queue = &sctp_sk(sk)->pd_lobby;
+			else {
+				clear_pd = event->msg_flags & MSG_EOR;
+				queue = &sk->sk_receive_queue;
+			}
+		} else {
+			/*
+			 * If fragment interleave is enabled, we
+			 * can queue this to the recieve queue instead
+			 * of the lobby.
+			 */
+			if (sctp_sk(sk)->frag_interleave)
+				queue = &sk->sk_receive_queue;
+			else
+				queue = &sctp_sk(sk)->pd_lobby;
 		}
-	} else
-		queue = &sctp_sk(sk)->pd_lobby;
-
+	}
 
 	/* If we are harvesting multiple skbs they will be
 	 * collected on a list.
@@ -826,18 +860,29 @@ void sctp_ulpq_partial_delivery(struct sctp_ulpq *ulpq,
 {
 	struct sctp_ulpevent *event;
 	struct sctp_association *asoc;
+	struct sctp_sock *sp;
 
 	asoc = ulpq->asoc;
+	sp = sctp_sk(asoc->base.sk);
 
-	/* Are we already in partial delivery mode?  */
-	if (!sctp_sk(asoc->base.sk)->pd_mode) {
+	/* If the association is already in Partial Delivery mode
+	 * we have noting to do.
+	 */
+	if (ulpq->pd_mode)
+		return;
 
+	/* If the user enabled fragment interleave socket option,
+	 * multiple associations can enter partial delivery.
+	 * Otherwise, we can only enter partial delivery if the
+	 * socket is not in partial deliver mode.
+	 */
+	if (sp->frag_interleave || atomic_read(&sp->pd_mode) == 0) {
 		/* Is partial delivery possible?  */
 		event = sctp_ulpq_retrieve_first(ulpq);
 		/* Send event to the ULP.   */
 		if (event) {
 			sctp_ulpq_tail_event(ulpq, event);
-			sctp_sk(asoc->base.sk)->pd_mode = 1;
+			atomic_inc(&sp->pd_mode);
 			ulpq->pd_mode = 1;
 			return;
 		}