Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

[linux.git] / fs / ocfs2 / cluster / tcp.c

diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c
index ea63d6461f55f612d97f2bad7112be5debd5d284..dfda2ffdb16c15aa8338b1de6f58ccc42ff5b9ba 100644 (file)
--- a/fs/ocfs2/cluster/tcp.c
+++ b/fs/ocfs2/cluster/tcp.c
@@ -262,17 +262,17 @@ static void o2net_update_recv_stats(struct o2net_sock_container *sc)
 
 #endif /* CONFIG_OCFS2_FS_STATS */
 
-static inline int o2net_reconnect_delay(void)
+static inline unsigned int o2net_reconnect_delay(void)
 {
        return o2nm_single_cluster->cl_reconnect_delay_ms;
 }
 
-static inline int o2net_keepalive_delay(void)
+static inline unsigned int o2net_keepalive_delay(void)
 {
        return o2nm_single_cluster->cl_keepalive_delay_ms;
 }
 
-static inline int o2net_idle_timeout(void)
+static inline unsigned int o2net_idle_timeout(void)
 {
        return o2nm_single_cluster->cl_idle_timeout_ms;
 }
@@ -1937,18 +1937,30 @@ static void o2net_listen_data_ready(struct sock *sk, int bytes)
                goto out;
        }
 
-       /* ->sk_data_ready is also called for a newly established child socket
-        * before it has been accepted and the acceptor has set up their
-        * data_ready.. we only want to queue listen work for our listening
-        * socket */
+       /* This callback may called twice when a new connection
+        * is  being established as a child socket inherits everything
+        * from a parent LISTEN socket, including the data_ready cb of
+        * the parent. This leads to a hazard. In o2net_accept_one()
+        * we are still initializing the child socket but have not
+        * changed the inherited data_ready callback yet when
+        * data starts arriving.
+        * We avoid this hazard by checking the state.
+        * For the listening socket,  the state will be TCP_LISTEN; for the new
+        * socket, will be  TCP_ESTABLISHED. Also, in this case,
+        * sk->sk_user_data is not a valid function pointer.
+        */
+
        if (sk->sk_state == TCP_LISTEN) {
                mlog(ML_TCP, "bytes: %d\n", bytes);
                queue_work(o2net_wq, &o2net_listen_work);
+       } else {
+               ready = NULL;
        }
 
 out:
        read_unlock(&sk->sk_callback_lock);
-       ready(sk, bytes);
+       if (ready != NULL)
+               ready(sk, bytes);
 }
 
 static int o2net_open_listening_sock(__be32 addr, __be16 port)