3 files changed, 65 insertions, 4 deletions

diff --git a/net/ipv4/ipvs/ip_vs_conn.c b/net/ipv4/ipvs/ip_vs_conn.c
index 4b702f7..b7eeae6 100644
--- a/net/ipv4/ipvs/ip_vs_conn.c
+++ b/net/ipv4/ipvs/ip_vs_conn.c
@@ -426,6 +426,25 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
 
 
 /*
+ * Check if there is a destination for the connection, if so
+ * bind the connection to the destination.
+ */
+struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp)
+{
+	struct ip_vs_dest *dest;
+
+	if ((cp) && (!cp->dest)) {
+		dest = ip_vs_find_dest(cp->daddr, cp->dport,
+				       cp->vaddr, cp->vport, cp->protocol);
+		ip_vs_bind_dest(cp, dest);
+		return dest;
+	} else
+		return NULL;
+}
+EXPORT_SYMBOL(ip_vs_try_bind_dest);
+
+
+/*
  *	Unbind a connection entry with its VS destination
  *	Called by the ip_vs_conn_expire function.
  */
diff --git a/net/ipv4/ipvs/ip_vs_ctl.c b/net/ipv4/ipvs/ip_vs_ctl.c
index 7345fc2..3c4d22a 100644
--- a/net/ipv4/ipvs/ip_vs_ctl.c
+++ b/net/ipv4/ipvs/ip_vs_ctl.c
@@ -579,6 +579,32 @@ ip_vs_lookup_dest(struct ip_vs_service *svc, __be32 daddr, __be16 dport)
 	return NULL;
 }
 
+/*
+ * Find destination by {daddr,dport,vaddr,protocol}
+ * Cretaed to be used in ip_vs_process_message() in
+ * the backup synchronization daemon. It finds the
+ * destination to be bound to the received connection
+ * on the backup.
+ *
+ * ip_vs_lookup_real_service() looked promissing, but
+ * seems not working as expected.
+ */
+struct ip_vs_dest *ip_vs_find_dest(__be32 daddr, __be16 dport,
+				    __be32 vaddr, __be16 vport, __u16 protocol)
+{
+	struct ip_vs_dest *dest;
+	struct ip_vs_service *svc;
+
+	svc = ip_vs_service_get(0, protocol, vaddr, vport);
+	if (!svc)
+		return NULL;
+	dest = ip_vs_lookup_dest(svc, daddr, dport);
+	if (dest)
+		atomic_inc(&dest->refcnt);
+	ip_vs_service_put(svc);
+	return dest;
+}
+EXPORT_SYMBOL(ip_vs_find_dest);
 
 /*
  *  Lookup dest by {svc,addr,port} in the destination trash.
diff --git a/net/ipv4/ipvs/ip_vs_sync.c b/net/ipv4/ipvs/ip_vs_sync.c
index 0d4d972..b1694d6 100644
--- a/net/ipv4/ipvs/ip_vs_sync.c
+++ b/net/ipv4/ipvs/ip_vs_sync.c
@@ -284,6 +284,7 @@ static void ip_vs_process_message(const char *buffer, const size_t buflen)
 	struct ip_vs_sync_conn_options *opt;
 	struct ip_vs_conn *cp;
 	struct ip_vs_protocol *pp;
+	struct ip_vs_dest *dest;
 	char *p;
 	int i;
 
@@ -317,20 +318,35 @@ static void ip_vs_process_message(const char *buffer, const size_t buflen)
 					       s->caddr, s->cport,
 					       s->vaddr, s->vport);
 		if (!cp) {
+			/*
+			 * Find the appropriate destination for the connection.
+			 * If it is not found the connection will remain unbound
+			 * but still handled.
+			 */
+			dest = ip_vs_find_dest(s->daddr, s->dport,
+					       s->vaddr, s->vport,
+					       s->protocol);
 			cp = ip_vs_conn_new(s->protocol,
 					    s->caddr, s->cport,
 					    s->vaddr, s->vport,
 					    s->daddr, s->dport,
-					    flags, NULL);
+					    flags, dest);
+			if (dest)
+				atomic_dec(&dest->refcnt);
 			if (!cp) {
 				IP_VS_ERR("ip_vs_conn_new failed\n");
 				return;
 			}
 			cp->state = ntohs(s->state);
 		} else if (!cp->dest) {
-			/* it is an entry created by the synchronization */
-			cp->state = ntohs(s->state);
-			cp->flags = flags | IP_VS_CONN_F_HASHED;
+			dest = ip_vs_try_bind_dest(cp);
+			if (!dest) {
+				/* it is an unbound entry created by
+				 * synchronization */
+				cp->state = ntohs(s->state);
+				cp->flags = flags | IP_VS_CONN_F_HASHED;
+			} else
+				atomic_dec(&dest->refcnt);
 		}	/* Note that we don't touch its state and flags
 			   if it is a normal entry. */