1 files changed, 9 insertions, 2 deletions

diff --git a/net/dccp/input.c b/net/dccp/input.c
index 3c4cbff82e95..ce8396b126d2 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -136,8 +136,15 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
                      DCCP_PKT_WITHOUT_ACK_SEQ))
                         dp->dccps_gar = DCCP_SKB_CB(skb)->dccpd_ack_seq;
         } else {
-                LIMIT_NETDEBUG(KERN_WARNING "DCCP: Step 6 failed, "
-                                            "sending SYNC...\n");
+                LIMIT_NETDEBUG(KERN_WARNING "DCCP: Step 6 failed for %s packet, "
+                                            "(LSWL(%llu) <= P.seqno(%llu) <= S.SWH(%llu)) and "
+                                            "(P.ackno %s or LAWL(%llu) <= P.ackno(%llu) <= S.AWH(%llu), "
+                                            "sending SYNC...\n",
+                               dccp_packet_name(dh->dccph_type),
+                               lswl, DCCP_SKB_CB(skb)->dccpd_seq, dp->dccps_swh,
+                               (DCCP_SKB_CB(skb)->dccpd_ack_seq ==
+                                DCCP_PKT_WITHOUT_ACK_SEQ) ? "doesn't exist" : "exists",
+                               lawl, DCCP_SKB_CB(skb)->dccpd_ack_seq, dp->dccps_awh);
                 dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC);
                 return -1;
         }