4 files changed, 69 insertions, 4 deletions

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index 41870564df8e..1fd1ee896f39 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -901,6 +901,10 @@ extern int ip_vs_use_count_inc(void);
 extern void ip_vs_use_count_dec(void);
 extern int ip_vs_control_init(void);
 extern void ip_vs_control_cleanup(void);
+extern struct ip_vs_dest *
+ip_vs_find_dest(__be32 daddr, __be16 dport,
+                 __be32 vaddr, __be16 vport, __u16 protocol);
+extern struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp);
 
 
 /*
diff --git a/net/ipv4/ipvs/ip_vs_conn.c b/net/ipv4/ipvs/ip_vs_conn.c
index 4b702f708d30..b7eeae622d9b 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 7345fc252a23..3c4d22a468ec 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 0d4d9721cbd4..b1694d67abb9 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. */