SUNRPC: Don't call connect() more than once on a TCP socket

From: Trond Myklebust <trond.myklebust@hammerspace.com>

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 <enrico.scholz@sigma-chemnitz.de>
Fixes: 3be232f11a3c ("SUNRPC: Prevent immediate close+reconnect")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
[meenashanmugam: Fix merge conflict in xs_tcp_setup_socket]
Signed-off-by: Meena Shanmugam <meenashanmugam@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Meena Shanmugam 2022-05-18 18:40:10 +00:00 committed by Greg Kroah-Hartman
parent aa4d71edd6
commit 975a0f14d5
2 changed files with 13 additions and 10 deletions

View File

@ -90,6 +90,7 @@ struct sock_xprt {
#define XPRT_SOCK_WAKE_WRITE (5)
#define XPRT_SOCK_WAKE_PENDING (6)
#define XPRT_SOCK_WAKE_DISCONNECT (7)
#define XPRT_SOCK_CONNECT_SENT (8)
#endif /* __KERNEL__ */

View File

@ -2384,10 +2384,14 @@ 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;
@ -2418,6 +2422,8 @@ static void xs_tcp_setup_socket(struct work_struct *work)
break;
case 0:
case -EINPROGRESS:
set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
fallthrough;
case -EALREADY:
xprt_unlock_connect(xprt, transport);
return;
@ -2469,13 +2475,9 @@ 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);