From 5d69622eb0361e5ad266d49f6bf312e0bdb3c654 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Wed, 16 Mar 2022 19:10:43 -0400 Subject: SUNRPC: Don't call connect() more than once on a TCP socket commit 89f42494f92f448747bd8a7ab1ae8b5d5520577d upstream. Avoid socket state races due to repeated calls to ->connect() using the same socket. If connect() returns 0 due to the connection having completed, but we are in fact in a closing state, then we may leave the XPRT_CONNECTING flag set on the transport. Reported-by: Enrico Scholz Fixes: 3be232f11a3c ("SUNRPC: Prevent immediate close+reconnect") Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- net/sunrpc/xprtsock.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) (limited to 'net') diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 8bc58302e550..c2f7819827b6 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -2257,6 +2257,7 @@ static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock) fallthrough; case -EINPROGRESS: /* SYN_SENT! */ + set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state); if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO) xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO; break; @@ -2282,10 +2283,14 @@ static void xs_tcp_setup_socket(struct work_struct *work) struct rpc_xprt *xprt = &transport->xprt; int status = -EIO; - if (!sock) { - sock = xs_create_sock(xprt, transport, - xs_addr(xprt)->sa_family, SOCK_STREAM, - IPPROTO_TCP, true); + if (xprt_connected(xprt)) + goto out; + if (test_and_clear_bit(XPRT_SOCK_CONNECT_SENT, + &transport->sock_state) || + !sock) { + xs_reset_transport(transport); + sock = xs_create_sock(xprt, transport, xs_addr(xprt)->sa_family, + SOCK_STREAM, IPPROTO_TCP, true); if (IS_ERR(sock)) { status = PTR_ERR(sock); goto out; @@ -2365,13 +2370,9 @@ static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task) WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport)); - if (transport->sock != NULL && !xprt_connecting(xprt)) { + if (transport->sock != NULL) { dprintk("RPC: xs_connect delayed xprt %p for %lu " - "seconds\n", - xprt, xprt->reestablish_timeout / HZ); - - /* Start by resetting any existing state */ - xs_reset_transport(transport); + "seconds\n", xprt, xprt->reestablish_timeout / HZ); delay = xprt_reconnect_delay(xprt); xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO); -- cgit v1.2.3