From f711a6ae062caeee46067b2f2f12ffda319ae73c Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan Date: Tue, 5 May 2015 15:20:51 -0400 Subject: net/rds: RDS-TCP: Always create a new rds_sock for an incoming connection. When running RDS over TCP, the active (client) side connects to the listening ("passive") side at the RDS_TCP_PORT. After the connection is established, if the client side reboots (potentially without even sending a FIN) the server still has a TCP socket in the esablished state. If the server-side now gets a new SYN comes from the client with a different client port, TCP will create a new socket-pair, but the RDS layer will incorrectly pull up the old rds_connection (which is still associated with the stale t_sock and RDS socket state). This patch corrects this behavior by having rds_tcp_accept_one() always create a new connection for an incoming TCP SYN. The rds and tcp state associated with the old socket-pair is cleaned up via the rds_tcp_state_change() callback which would typically be invoked in most cases when the client-TCP sends a FIN on TCP restart, triggering a transition to CLOSE_WAIT state. In the rarer event of client death without a FIN, TCP_KEEPALIVE probes on the socket will detect the stale socket, and the TCP transition to CLOSE state will trigger the RDS state cleanup. Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller --- net/rds/connection.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/rds/connection.c') diff --git a/net/rds/connection.c b/net/rds/connection.c index 14f041398ca1..60f0cd6ed15f 100644 --- a/net/rds/connection.c +++ b/net/rds/connection.c @@ -126,7 +126,10 @@ static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr, struct rds_transport *loop_trans; unsigned long flags; int ret; + struct rds_transport *otrans = trans; + if (!is_outgoing && otrans->t_type == RDS_TRANS_TCP) + goto new_conn; rcu_read_lock(); conn = rds_conn_lookup(head, laddr, faddr, trans); if (conn && conn->c_loopback && conn->c_trans != &rds_loop_transport && @@ -142,6 +145,7 @@ static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr, if (conn) goto out; +new_conn: conn = kmem_cache_zalloc(rds_conn_slab, gfp); if (!conn) { conn = ERR_PTR(-ENOMEM); -- cgit v1.2.3