1 files changed, 35 insertions, 30 deletions

diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 4328ad5439c9..247ebc95c1e5 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -420,7 +420,7 @@ void sctp_retransmit_mark(struct sctp_outq *q,
                  * be added to the retransmit queue.
                  */
                 if ((reason == SCTP_RTXR_FAST_RTX  &&
-                            (chunk->fast_retransmit > 0)) ||
+                            (chunk->fast_retransmit == SCTP_NEED_FRTX)) ||
                     (reason != SCTP_RTXR_FAST_RTX  && !chunk->tsn_gap_acked)) {
                         /* If this chunk was sent less then 1 rto ago, do not
                          * retransmit this chunk, but give the peer time
@@ -650,8 +650,8 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
                         /* Mark the chunk as ineligible for fast retransmit
                          * after it is retransmitted.
                          */
-                        if (chunk->fast_retransmit > 0)
-                                chunk->fast_retransmit = -1;
+                        if (chunk->fast_retransmit == SCTP_NEED_FRTX)
+                                chunk->fast_retransmit = SCTP_DONT_FRTX;
 
                         /* Force start T3-rtx timer when fast retransmitting
                          * the earliest outstanding TSN
@@ -680,8 +680,8 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
          */
         if (rtx_timeout || fast_rtx) {
                 list_for_each_entry(chunk1, lqueue, transmitted_list) {
-                        if (chunk1->fast_retransmit > 0)
-                                chunk1->fast_retransmit = -1;
+                        if (chunk1->fast_retransmit == SCTP_NEED_FRTX)
+                                chunk1->fast_retransmit = SCTP_DONT_FRTX;
                 }
         }
 
@@ -1129,12 +1129,13 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
         unsigned outstanding;
         struct sctp_transport *primary = asoc->peer.primary_path;
         int count_of_newacks = 0;
+        int gap_ack_blocks;
 
         /* Grab the association's destination address list. */
         transport_list = &asoc->peer.transport_addr_list;
 
         sack_ctsn = ntohl(sack->cum_tsn_ack);
-
+        gap_ack_blocks = ntohs(sack->num_gap_ack_blocks);
         /*
          * SFR-CACC algorithm:
          * On receipt of a SACK the sender SHOULD execute the
@@ -1144,35 +1145,38 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
          * on the current primary, the CHANGEOVER_ACTIVE flag SHOULD be
          * cleared. The CYCLING_CHANGEOVER flag SHOULD also be cleared for
          * all destinations.
-         */
-        if (TSN_lte(primary->cacc.next_tsn_at_change, sack_ctsn)) {
-                primary->cacc.changeover_active = 0;
-                list_for_each_entry(transport, transport_list,
-                                transports) {
-                        transport->cacc.cycling_changeover = 0;
-                }
-        }
-
-        /*
-         * SFR-CACC algorithm:
          * 2) If the SACK contains gap acks and the flag CHANGEOVER_ACTIVE
          * is set the receiver of the SACK MUST take the following actions:
          *
          * A) Initialize the cacc_saw_newack to 0 for all destination
          * addresses.
+         *
+         * Only bother if changeover_active is set. Otherwise, this is
+         * totally suboptimal to do on every SACK.
          */
-        if (sack->num_gap_ack_blocks &&
-            primary->cacc.changeover_active) {
-                list_for_each_entry(transport, transport_list, transports) {
-                        transport->cacc.cacc_saw_newack = 0;
+        if (primary->cacc.changeover_active) {
+                u8 clear_cycling = 0;
+
+                if (TSN_lte(primary->cacc.next_tsn_at_change, sack_ctsn)) {
+                        primary->cacc.changeover_active = 0;
+                        clear_cycling = 1;
+                }
+
+                if (clear_cycling || gap_ack_blocks) {
+                        list_for_each_entry(transport, transport_list,
+                                        transports) {
+                                if (clear_cycling)
+                                        transport->cacc.cycling_changeover = 0;
+                                if (gap_ack_blocks)
+                                        transport->cacc.cacc_saw_newack = 0;
+                        }
                 }
         }
 
         /* Get the highest TSN in the sack. */
         highest_tsn = sack_ctsn;
-        if (sack->num_gap_ack_blocks)
-                highest_tsn +=
-                    ntohs(frags[ntohs(sack->num_gap_ack_blocks) - 1].gab.end);
+        if (gap_ack_blocks)
+                highest_tsn += ntohs(frags[gap_ack_blocks - 1].gab.end);
 
         if (TSN_lt(asoc->highest_sacked, highest_tsn)) {
                 highest_new_tsn = highest_tsn;
@@ -1181,11 +1185,11 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
                 highest_new_tsn = sctp_highest_new_tsn(sack, asoc);
         }
 
+
         /* Run through the retransmit queue.  Credit bytes received
          * and free those chunks that we can.
          */
         sctp_check_transmitted(q, &q->retransmit, NULL, sack, highest_new_tsn);
-        sctp_mark_missing(q, &q->retransmit, NULL, highest_new_tsn, 0);
 
         /* Run through the transmitted queue.
          * Credit bytes received and free those chunks which we can.
@@ -1204,9 +1208,10 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
                         count_of_newacks ++;
         }
 
-        list_for_each_entry(transport, transport_list, transports) {
-                sctp_mark_missing(q, &transport->transmitted, transport,
-                                  highest_new_tsn, count_of_newacks);
+        if (gap_ack_blocks) {
+                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.  */
@@ -1651,7 +1656,7 @@ static void sctp_mark_missing(struct sctp_outq *q,
                  * chunk if it has NOT been fast retransmitted or marked for
                  * fast retransmit already.
                  */
-                if (!chunk->fast_retransmit &&
+                if (chunk->fast_retransmit == SCTP_CAN_FRTX &&
                     !chunk->tsn_gap_acked &&
                     TSN_lt(tsn, highest_new_tsn_in_sack)) {
 
@@ -1676,7 +1681,7 @@ static void sctp_mark_missing(struct sctp_outq *q,
                  */
 
                 if (chunk->tsn_missing_report >= 3) {
-                        chunk->fast_retransmit = 1;
+                        chunk->fast_retransmit = SCTP_NEED_FRTX;
                         do_fast_retransmit = 1;
                 }
         }