[DCCP]: Increment sequence numbers on retransmitted Response packets

Problem:

1 files changed, 9 insertions, 7 deletions

diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index d3de696fe4bf..5b2773efd7c7 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -196,15 +196,17 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
 
         /* Check for retransmitted REQUEST */
         if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) {
-                if (after48(DCCP_SKB_CB(skb)->dccpd_seq,
-                            dccp_rsk(req)->dreq_isr)) {
-                        struct dccp_request_sock *dreq = dccp_rsk(req);
+                struct dccp_request_sock *dreq = dccp_rsk(req);
 
+                if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) {
                         dccp_pr_debug("Retransmitted REQUEST\n");
-                        /* Send another RESPONSE packet */
-                        dccp_set_seqno(&dreq->dreq_iss, dreq->dreq_iss + 1);
-                        dccp_set_seqno(&dreq->dreq_isr,
-                                       DCCP_SKB_CB(skb)->dccpd_seq);
+                        dreq->dreq_isr = DCCP_SKB_CB(skb)->dccpd_seq;
+                        /*
+                         * Send another RESPONSE packet
+                         * To protect against Request floods, increment retrans
+                         * counter (backoff, monitored by dccp_response_timer).
+                         */
+                        req->retrans++;
                         req->rsk_ops->rtx_syn_ack(sk, req, NULL);
                 }
                 /* Network Duplicate, discard packet */