On Sat, May 14, 2022 at 05:34:52AM +0000, Meena Shanmugam wrote:
> From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
>
> 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@xxxxxxxxxxxxxxxxx>
> Fixes: 3be232f11a3c ("SUNRPC: Prevent immediate close+reconnect")
> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> [meenashanmugam: Backported to 5.10: Fixed merge conflict in xs_tcp_setup_socket]
> Signed-off-by: Meena Shanmugam <meenashanmugam@xxxxxxxxxx>
> ---
> include/linux/sunrpc/xprtsock.h | 1 +
> net/sunrpc/xprtsock.c | 21 +++++++++++----------
> 2 files changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/include/linux/sunrpc/xprtsock.h b/include/linux/sunrpc/xprtsock.h
> index 8c2a712cb242..689062afdd61 100644
> --- a/include/linux/sunrpc/xprtsock.h
> +++ b/include/linux/sunrpc/xprtsock.h
> @@ -89,5 +89,6 @@ 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 /* _LINUX_SUNRPC_XPRTSOCK_H */
> diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
> index 60c58eb9a456..33a81f9703b1 100644
> --- a/net/sunrpc/xprtsock.c
> +++ b/net/sunrpc/xprtsock.c
> @@ -2260,10 +2260,14 @@ 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;
> @@ -2294,6 +2298,7 @@ static void xs_tcp_setup_socket(struct work_struct *work)
> break;
> case 0:
> case -EINPROGRESS:
> + set_bit(XPRT_SOCK_CONNECT_SENT, &transport->sock_state);
> case -EALREADY:
> xprt_unlock_connect(xprt, transport);
> return;
> @@ -2345,13 +2350,9 @@ 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);
> --
> 2.36.0.550.gb090851708-goog
>
This commit added a build warning. Always properly test your changes,
they can not add warnings.
I've fixed it up by hand now.
thanks,
greg k-h
