From aed20a53a7d91e45c6a8cb8920c77aaaa88f76ee Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan Date: Sun, 16 Jul 2017 16:43:46 -0700 Subject: rds: cancel send/recv work before queuing connection shutdown We could end up executing rds_conn_shutdown before the rds_recv_worker thread, then rds_conn_shutdown -> rds_tcp_conn_shutdown can do a sock_release and set sock->sk to null, which may interleave in bad ways with rds_recv_worker, e.g., it could result in: "BUG: unable to handle kernel NULL pointer dereference at 0000000000000078" [ffff881769f6fd70] release_sock at ffffffff815f337b [ffff881769f6fd90] rds_tcp_recv at ffffffffa043c888 [rds_tcp] [ffff881769f6fdb0] rds_recv_worker at ffffffffa04a4810 [rds] [ffff881769f6fde0] process_one_work at ffffffff810a14c1 [ffff881769f6fe40] worker_thread at ffffffff810a1940 [ffff881769f6fec0] kthread at ffffffff810a6b1e Also, do not enqueue any new shutdown workq items when the connection is shutting down (this may happen for rds-tcp in softirq mode, if a FIN or CLOSE is received while the modules is in the middle of an unload) Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller --- net/rds/rds.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/rds/rds.h') diff --git a/net/rds/rds.h b/net/rds/rds.h index 516bcc89b46f..3382695bf46c 100644 --- a/net/rds/rds.h +++ b/net/rds/rds.h @@ -700,7 +700,7 @@ struct rds_connection *rds_conn_create_outgoing(struct net *net, void rds_conn_shutdown(struct rds_conn_path *cpath); void rds_conn_destroy(struct rds_connection *conn); void rds_conn_drop(struct rds_connection *conn); -void rds_conn_path_drop(struct rds_conn_path *cpath); +void rds_conn_path_drop(struct rds_conn_path *cpath, bool destroy); void rds_conn_connect_if_down(struct rds_connection *conn); void rds_conn_path_connect_if_down(struct rds_conn_path *cp); void rds_for_each_conn_info(struct socket *sock, unsigned int len, -- cgit v1.2.3