6 files changed, 66 insertions, 2 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index ac53bfbdfe16..adab9dc58183 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -752,6 +752,7 @@ struct proto {
         /* Keeping track of sk's, looking them up, and port selection methods. */
         void                    (*hash)(struct sock *sk);
         void                    (*unhash)(struct sock *sk);
+        void                    (*rehash)(struct sock *sk);
         int                     (*get_port)(struct sock *sk, unsigned short snum);
 
         /* Keeping track of sockets in use */
diff --git a/include/net/udp.h b/include/net/udp.h
index 7abdf305da50..a184d3496b13 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -151,6 +151,7 @@ static inline void udp_lib_hash(struct sock *sk)
 }
 
 extern void udp_lib_unhash(struct sock *sk);
+extern void udp_lib_rehash(struct sock *sk, u16 new_hash);
 
 static inline void udp_lib_close(struct sock *sk, long timeout)
 {
diff --git a/net/ipv4/datagram.c b/net/ipv4/datagram.c
index f0550941df7b..721a8a37b45c 100644
--- a/net/ipv4/datagram.c
+++ b/net/ipv4/datagram.c
@@ -62,8 +62,11 @@ int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
         }
         if (!inet->inet_saddr)
                 inet->inet_saddr = rt->rt_src;  /* Update source address */
-        if (!inet->inet_rcv_saddr)
+        if (!inet->inet_rcv_saddr) {
                 inet->inet_rcv_saddr = rt->rt_src;
+                if (sk->sk_prot->rehash)
+                        sk->sk_prot->rehash(sk);
+        }
         inet->inet_daddr = rt->rt_dst;
         inet->inet_dport = usin->sin_port;
         sk->sk_state = TCP_ESTABLISHED;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 32e0bef60d0a..fb23c2e63b52 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1260,6 +1260,49 @@ void udp_lib_unhash(struct sock *sk)
 }
 EXPORT_SYMBOL(udp_lib_unhash);
 
+/*
+ * inet_rcv_saddr was changed, we must rehash secondary hash
+ */
+void udp_lib_rehash(struct sock *sk, u16 newhash)
+{
+        if (sk_hashed(sk)) {
+                struct udp_table *udptable = sk->sk_prot->h.udp_table;
+                struct udp_hslot *hslot, *hslot2, *nhslot2;
+
+                hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
+                nhslot2 = udp_hashslot2(udptable, newhash);
+                udp_sk(sk)->udp_portaddr_hash = newhash;
+                if (hslot2 != nhslot2) {
+                        hslot = udp_hashslot(udptable, sock_net(sk),
+                                             udp_sk(sk)->udp_port_hash);
+                        /* we must lock primary chain too */
+                        spin_lock_bh(&hslot->lock);
+
+                        spin_lock(&hslot2->lock);
+                        hlist_nulls_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
+                        hslot2->count--;
+                        spin_unlock(&hslot2->lock);
+
+                        spin_lock(&nhslot2->lock);
+                        hlist_nulls_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
+                                                 &nhslot2->head);
+                        nhslot2->count++;
+                        spin_unlock(&nhslot2->lock);
+
+                        spin_unlock_bh(&hslot->lock);
+                }
+        }
+}
+EXPORT_SYMBOL(udp_lib_rehash);
+
+static void udp_v4_rehash(struct sock *sk)
+{
+        u16 new_hash = udp4_portaddr_hash(sock_net(sk),
+                                          inet_sk(sk)->inet_rcv_saddr,
+                                          inet_sk(sk)->inet_num);
+        udp_lib_rehash(sk, new_hash);
+}
+
 static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
         int rc;
@@ -1843,6 +1886,7 @@ struct proto udp_prot = {
         .backlog_rcv       = __udp_queue_rcv_skb,
         .hash              = udp_lib_hash,
         .unhash            = udp_lib_unhash,
+        .rehash            = udp_v4_rehash,
         .get_port          = udp_v4_get_port,
         .memory_allocated  = &udp_memory_allocated,
         .sysctl_mem        = sysctl_udp_mem,
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 7d929a22cbc2..ef371aa01ac5 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -105,9 +105,12 @@ ipv4_connected:
                 if (ipv6_addr_any(&np->saddr))
                         ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
 
-                if (ipv6_addr_any(&np->rcv_saddr))
+                if (ipv6_addr_any(&np->rcv_saddr)) {
                         ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
                                                &np->rcv_saddr);
+                        if (sk->sk_prot->rehash)
+                                sk->sk_prot->rehash(sk);
+                }
 
                 goto out;
         }
@@ -181,6 +184,8 @@ ipv4_connected:
         if (ipv6_addr_any(&np->rcv_saddr)) {
                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
                 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
+                if (sk->sk_prot->rehash)
+                        sk->sk_prot->rehash(sk);
         }
 
         ip6_dst_store(sk, dst,
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 1dd1affdead2..5acb3560ff15 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -111,6 +111,15 @@ int udp_v6_get_port(struct sock *sk, unsigned short snum)
         return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
 }
 
+static void udp_v6_rehash(struct sock *sk)
+{
+        u16 new_hash = udp6_portaddr_hash(sock_net(sk),
+                                          &inet6_sk(sk)->rcv_saddr,
+                                          inet_sk(sk)->inet_num);
+
+        udp_lib_rehash(sk, new_hash);
+}
+
 static inline int compute_score(struct sock *sk, struct net *net,
                                 unsigned short hnum,
                                 struct in6_addr *saddr, __be16 sport,
@@ -1447,6 +1456,7 @@ struct proto udpv6_prot = {
         .backlog_rcv       = udpv6_queue_rcv_skb,
         .hash              = udp_lib_hash,
         .unhash            = udp_lib_unhash,
+        .rehash            = udp_v6_rehash,
         .get_port          = udp_v6_get_port,
         .memory_allocated  = &udp_memory_allocated,
         .sysctl_mem        = sysctl_udp_mem,