1 files changed, 37 insertions, 57 deletions

diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index ccf4c5629b3c..5684e14932bd 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -208,7 +208,6 @@ void dccp_req_err(struct sock *sk, u64 seq)
 
 	if (!between48(seq, dccp_rsk(req)->dreq_iss, dccp_rsk(req)->dreq_gss)) {
 		NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
-		reqsk_put(req);
 	} else {
 		/*
 		 * Still in RESPOND, just remove it silently.
@@ -218,6 +217,7 @@ void dccp_req_err(struct sock *sk, u64 seq)
 		 */
 		inet_csk_reqsk_queue_drop(req->rsk_listener, req);
 	}
+	reqsk_put(req);
 }
 EXPORT_SYMBOL(dccp_req_err);
 
@@ -390,9 +390,12 @@ static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb)
  *
  * This is the equivalent of TCP's tcp_v4_syn_recv_sock
  */
-struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
+struct sock *dccp_v4_request_recv_sock(const struct sock *sk,
+				       struct sk_buff *skb,
 				       struct request_sock *req,
-				       struct dst_entry *dst)
+				       struct dst_entry *dst,
+				       struct request_sock *req_unhash,
+				       bool *own_req)
 {
 	struct inet_request_sock *ireq;
 	struct inet_sock *newinet;
@@ -425,7 +428,7 @@ struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
 
 	if (__inet_inherit_port(sk, newsk) < 0)
 		goto put_and_exit;
-	__inet_hash_nolisten(newsk, NULL);
+	*own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash));
 
 	return newsk;
 
@@ -443,36 +446,6 @@ put_and_exit:
 }
 EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock);
 
-static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
-{
-	const struct dccp_hdr *dh = dccp_hdr(skb);
-	const struct iphdr *iph = ip_hdr(skb);
-	struct sock *nsk;
-	/* Find possible connection requests. */
-	struct request_sock *req = inet_csk_search_req(sk, dh->dccph_sport,
-						       iph->saddr, iph->daddr);
-	if (req) {
-		nsk = dccp_check_req(sk, skb, req);
-		if (!nsk)
-			reqsk_put(req);
-		return nsk;
-	}
-	nsk = inet_lookup_established(sock_net(sk), &dccp_hashinfo,
-				      iph->saddr, dh->dccph_sport,
-				      iph->daddr, dh->dccph_dport,
-				      inet_iif(skb));
-	if (nsk != NULL) {
-		if (nsk->sk_state != DCCP_TIME_WAIT) {
-			bh_lock_sock(nsk);
-			return nsk;
-		}
-		inet_twsk_put(inet_twsk(nsk));
-		return NULL;
-	}
-
-	return sk;
-}
-
 static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk,
 					   struct sk_buff *skb)
 {
@@ -498,7 +471,7 @@ static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk,
 	return &rt->dst;
 }
 
-static int dccp_v4_send_response(struct sock *sk, struct request_sock *req)
+static int dccp_v4_send_response(const struct sock *sk, struct request_sock *req)
 {
 	int err = -1;
 	struct sk_buff *skb;
@@ -527,7 +500,7 @@ out:
 	return err;
 }
 
-static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
+static void dccp_v4_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
 {
 	int err;
 	const struct iphdr *rxiph;
@@ -624,7 +597,7 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 	if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
 		goto drop;
 
-	req = inet_reqsk_alloc(&dccp_request_sock_ops, sk);
+	req = inet_reqsk_alloc(&dccp_request_sock_ops, sk, true);
 	if (req == NULL)
 		goto drop;
 
@@ -704,18 +677,6 @@ int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 	 * NOTE: the check for the packet types is done in
 	 *	 dccp_rcv_state_process
 	 */
-	if (sk->sk_state == DCCP_LISTEN) {
-		struct sock *nsk = dccp_v4_hnd_req(sk, skb);
-
-		if (nsk == NULL)
-			goto discard;
-
-		if (nsk != sk) {
-			if (dccp_child_process(sk, nsk, skb))
-				goto reset;
-			return 0;
-		}
-	}
 
 	if (dccp_rcv_state_process(sk, skb, dh, skb->len))
 		goto reset;
@@ -723,7 +684,6 @@ int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 
 reset:
 	dccp_v4_ctl_send_reset(sk, skb);
-discard:
 	kfree_skb(skb);
 	return 0;
 }
@@ -841,15 +801,10 @@ static int dccp_v4_rcv(struct sk_buff *skb)
 				  DCCP_SKB_CB(skb)->dccpd_ack_seq);
 	}
 
-	/* Step 2:
-	 *	Look up flow ID in table and get corresponding socket */
+lookup:
 	sk = __inet_lookup_skb(&dccp_hashinfo, skb,
 			       dh->dccph_sport, dh->dccph_dport);
-	/*
-	 * Step 2:
-	 *	If no socket ...
-	 */
-	if (sk == NULL) {
+	if (!sk) {
 		dccp_pr_debug("failed to look up flow ID in table and "
 			      "get corresponding socket\n");
 		goto no_dccp_socket;
@@ -867,6 +822,31 @@ static int dccp_v4_rcv(struct sk_buff *skb)
 		goto no_dccp_socket;
 	}
 
+	if (sk->sk_state == DCCP_NEW_SYN_RECV) {
+		struct request_sock *req = inet_reqsk(sk);
+		struct sock *nsk = NULL;
+
+		sk = req->rsk_listener;
+		if (likely(sk->sk_state == DCCP_LISTEN)) {
+			nsk = dccp_check_req(sk, skb, req);
+		} else {
+			inet_csk_reqsk_queue_drop_and_put(sk, req);
+			goto lookup;
+		}
+		if (!nsk) {
+			reqsk_put(req);
+			goto discard_it;
+		}
+		if (nsk == sk) {
+			sock_hold(sk);
+			reqsk_put(req);
+		} else if (dccp_child_process(sk, nsk, skb)) {
+			dccp_v4_ctl_send_reset(sk, skb);
+			goto discard_it;
+		} else {
+			return 0;
+		}
+	}
 	/*
 	 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
 	 *	o if MinCsCov = 0, only packets with CsCov = 0 are accepted