[PATCH net 1/1] vsock: clear stale sk_err before listen()

From: Zihan Xi <redacted>

A failed loopback connect() can leave sk_err set on a reusable
AF_VSOCK socket. If userspace then calls listen() on the same socket,
the stale error remains attached to the listener. When a later child
reaches vsock_accept(), the accept path sees listener->sk_err,
rejects the child, and drops only the transient accept reference.

On virtio-based loopback this can leave the rejected child orphaned in
the vsock tables, so repeated iterations leak children and can
ultimately drive the guest into OOM.

Clear sk_err when a socket is transitioned into TCP_LISTEN so an
earlier failed connect() does not poison a new listening socket.

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Cc: stable@vger.kernel.org
Reported-by: Vega <redacted>
Assisted-by: Codex:gpt-5.4
Signed-off-by: Zihan Xi <redacted>
Signed-off-by: Ren Wei <redacted>
---
 net/vmw_vsock/af_vsock.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index a06f708f3..3482ba594 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c

@@ -1729,6 +1729,10 @@ static int vsock_listen(struct socket *sock, int backlog)
 		goto out;
 	}
 
+	/* sk_err might have been set as a result of an earlier
+	 * (failed) connect attempt.
+	 */
+	sk->sk_err = 0;
 	sk->sk_max_ack_backlog = backlog;
 	sk->sk_state = TCP_LISTEN;
 

-- 
2.43.0