[PATCH] vsock: bugfix port residue in server

From: Zhuang Shengen
Date: Wed May 10 2023 - 10:47:59 EST


When client and server establish a connection through vsock,
the client send a request to the server to initiate the connection,
then start a timer to wait for the server's response. When the server's
RESPONSE message arrives, the timer also times out and exits. The
server's RESPONSE message is processed first, and the connection is
established. However, the client's timer also times out, the original
processing logic of the client is to directly set the state of this vsock
to CLOSE and return ETIMEDOUT, User will release the port. It will not
notify the server when the port is released, causing the server port remain

when client's vsock_connect timeout,it should check sk state is
ESTABLISHED or not. if sk state is ESTABLISHED, it means the connection
is established, the client should not set the sk state to CLOSE

Note: I encountered this issue on kernel-4.18, which can be fixed by
this patch. Then I checked the latest code in the community
and found similar issue.

Signed-off-by: Zhuang Shengen <zhuangshengen@xxxxxxxxxx>
---
net/vmw_vsock/af_vsock.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 413407bb646c..efb8a0937a13 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1462,7 +1462,7 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
vsock_transport_cancel_pkt(vsk);
vsock_remove_connected(vsk);
goto out_wait;
- } else if (timeout == 0) {
+ } else if ((sk->sk_state != TCP_ESTABLISHED) && (timeout == 0)) {
err = -ETIMEDOUT;
sk->sk_state = TCP_CLOSE;
sock->state = SS_UNCONNECTED;
--
2.27.0