sctp: correctly mark missing chunks in fast recovery

According to RFC 4960 Section 7.2.4:
 					If an endpoint is in Fast
   Recovery and a SACK arrives that advances the Cumulative TSN Ack
   Point, the miss indications are incremented for all TSNs reported
   missing in the SACK.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

1 files changed, 13 insertions, 5 deletions

diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 786c4ff97ae4..b491a1aac3e4 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -1154,6 +1154,7 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
         struct sctp_transport *primary = asoc->peer.primary_path;
         int count_of_newacks = 0;
         int gap_ack_blocks;
+        u8 accum_moved = 0;
 
         /* Grab the association's destination address list. */
         transport_list = &asoc->peer.transport_addr_list;
@@ -1232,16 +1233,22 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
                         count_of_newacks ++;
         }
 
+        /* Move the Cumulative TSN Ack Point if appropriate.  */
+        if (TSN_lt(asoc->ctsn_ack_point, sack_ctsn)) {
+                asoc->ctsn_ack_point = sack_ctsn;
+                accum_moved = 1;
+        }
+
         if (gap_ack_blocks) {
+
+                if (asoc->fast_recovery && accum_moved)
+                        highest_new_tsn = highest_tsn;
+
                 list_for_each_entry(transport, transport_list, transports)
                         sctp_mark_missing(q, &transport->transmitted, transport,
                                           highest_new_tsn, count_of_newacks);
         }
 
-        /* Move the Cumulative TSN Ack Point if appropriate.  */
-        if (TSN_lt(asoc->ctsn_ack_point, sack_ctsn))
-                asoc->ctsn_ack_point = sack_ctsn;
-
         /* Update unack_data field in the assoc. */
         sctp_sack_update_unack_data(asoc, sack);
 
@@ -1685,7 +1692,8 @@ static void sctp_mark_missing(struct sctp_outq *q,
         struct sctp_chunk *chunk;
         __u32 tsn;
         char do_fast_retransmit = 0;
-        struct sctp_transport *primary = q->asoc->peer.primary_path;
+        struct sctp_association *asoc = q->asoc;
+        struct sctp_transport *primary = asoc->peer.primary_path;
 
         list_for_each_entry(chunk, transmitted_queue, transmitted_list) {