1 files changed, 35 insertions, 0 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 34085e3a4096..a0d373bd9065 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1652,6 +1652,41 @@ recv_urg:
         goto out;
 }
 
+void tcp_set_state(struct sock *sk, int state)
+{
+        int oldstate = sk->sk_state;
+
+        switch (state) {
+        case TCP_ESTABLISHED:
+                if (oldstate != TCP_ESTABLISHED)
+                        TCP_INC_STATS(TCP_MIB_CURRESTAB);
+                break;
+
+        case TCP_CLOSE:
+                if (oldstate == TCP_CLOSE_WAIT || oldstate == TCP_ESTABLISHED)
+                        TCP_INC_STATS(TCP_MIB_ESTABRESETS);
+
+                sk->sk_prot->unhash(sk);
+                if (inet_csk(sk)->icsk_bind_hash &&
+                    !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
+                        inet_put_port(&tcp_hashinfo, sk);
+                /* fall through */
+        default:
+                if (oldstate==TCP_ESTABLISHED)
+                        TCP_DEC_STATS(TCP_MIB_CURRESTAB);
+        }
+
+        /* Change state AFTER socket is unhashed to avoid closed
+         * socket sitting in hash tables.
+         */
+        sk->sk_state = state;
+
+#ifdef STATE_TRACE
+        SOCK_DEBUG(sk, "TCP sk=%p, State %s -> %s\n",sk, statename[oldstate],statename[state]);
+#endif
+}
+EXPORT_SYMBOL_GPL(tcp_set_state);
+
 /*
  *      State processing on a close. This implements the state shift for
  *      sending our FIN frame. Note that we only send a FIN for some