---

yaml
---
r: 106665
b: refs/heads/master
c: 73f18fd
h: refs/heads/master
i:
  106663: 576a76e
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 59435444a13ed52d3444c5df26b73d3086bcd57b
+refs/heads/master: 73f18fdbca3f92b90aeaee16f5175fe30496e218

trunk/net/dccp/output.c

@@ -53,8 +53,11 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 					  dccp_packet_hdr_len(dcb->dccpd_type);
 		int err, set_ack = 1;
 		u64 ackno = dp->dccps_gsr;
-
-		dccp_inc_seqno(&dp->dccps_gss);
+		/*
+		 * Increment GSS here already in case the option code needs it.
+		 * Update GSS for real only if option processing below succeeds.
+		 */
+		dcb->dccpd_seq = ADD48(dp->dccps_gss, 1);
 
 		switch (dcb->dccpd_type) {
 		case DCCP_PKT_DATA:
@@ -66,6 +69,9 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 
 		case DCCP_PKT_REQUEST:
 			set_ack = 0;
+			/* Use ISS on the first (non-retransmitted) Request. */
+			if (icsk->icsk_retransmits == 0)
+				dcb->dccpd_seq = dp->dccps_iss;
 			/* fall through */
 
 		case DCCP_PKT_SYNC:
@@ -84,8 +90,6 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 			break;
 		}
 
-		dcb->dccpd_seq = dp->dccps_gss;
-
 		if (dccp_insert_options(sk, skb)) {
 			kfree_skb(skb);
 			return -EPROTO;
@@ -103,7 +107,7 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 		/* XXX For now we're using only 48 bits sequence numbers */
 		dh->dccph_x	= 1;
 
-		dp->dccps_awh = dp->dccps_gss;
+		dccp_update_gss(sk, dcb->dccpd_seq);
 		dccp_hdr_set_seq(dh, dp->dccps_gss);
 		if (set_ack)
 			dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), ackno);
@@ -112,6 +116,11 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
 		case DCCP_PKT_REQUEST:
 			dccp_hdr_request(skb)->dccph_req_service =
 							dp->dccps_service;
+			/*
+			 * Limit Ack window to ISS <= P.ackno <= GSS, so that
+			 * only Responses to Requests we sent are considered.
+			 */
+			dp->dccps_awl = dp->dccps_iss;
 			break;
 		case DCCP_PKT_RESET:
 			dccp_hdr_reset(skb)->dccph_reset_code =
@@ -449,19 +458,7 @@ static inline void dccp_connect_init(struct sock *sk)
 
 	dccp_sync_mss(sk, dst_mtu(dst));
 
-	/*
-	 * SWL and AWL are initially adjusted so that they are not less than
-	 * the initial Sequence Numbers received and sent, respectively:
-	 *	SWL := max(GSR + 1 - floor(W/4), ISR),
-	 *	AWL := max(GSS - W' + 1, ISS).
-	 * These adjustments MUST be applied only at the beginning of the
-	 * connection.
-	 */
-	dccp_update_gss(sk, dp->dccps_iss);
-	dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss));
-
-	/* S.GAR - greatest valid acknowledgement number received on a non-Sync;
-	 *         initialized to S.ISS (sec. 8.5)                            */
+	/* Initialise GAR as per 8.5; AWL/AWH are set in dccp_transmit_skb() */
 	dp->dccps_gar = dp->dccps_iss;
 
 	icsk->icsk_retransmits = 0;