sunrpc: clear XPRT_SOCK_UPD_TIMEOUT when reset transport

BugLink: https://bugs.launchpad.net/bugs/2101915

[ Upstream commit 4db9ad82a6c823094da27de4825af693a3475d51 ]

Since transport->sock has been set to NULL during reset transport,
XPRT_SOCK_UPD_TIMEOUT also needs to be cleared. Otherwise, the
xs_tcp_set_socket_timeouts() may be triggered in xs_tcp_send_request()
to dereference the transport->sock that has been set to NULL.

Fixes: 7196dbb ("SUNRPC: Allow changing of the TCP timeout parameters on the fly")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
CVE-2024-56688
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Author: liujian56

net/sunrpc/xprtsock.c

@@ -1187,6 +1187,7 @@ static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
 	clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
 	clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
 	clear_bit(XPRT_SOCK_NOSPACE, &transport->sock_state);
+	clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
 }
 
 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)