From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	patches@lists.linux.dev,
	Wupeng Ma <mawupeng1@huawei.com>,
	Stefano Garzarella <sgarzare@redhat.com>,
	Nguyen Dinh Phi <phind.uet@gmail.com>,
	Paolo Abeni <pabeni@redhat.com>,
	Sasha Levin <sashal@kernel.org>
Subject: [PATCH 6.12 1219/1376] vsock: use sock_error() to consume sk_err after a failed connect
Date: Sat, 12 Sep 2026 09:00:45 +0200
Message-ID: <20260912065634.719397104@linuxfoundation.org>
In-Reply-To: <20260912065607.535295758@linuxfoundation.org>
References: <20260912065607.535295758@linuxfoundation.org>
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6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nguyen Dinh Phi <phind.uet@gmail.com>

[ Upstream commit 96cbf89993091a163bfedec52a3bd683dc94b3b4 ]

vsock_connect() returns sk_err to userspace but does not clear it:
  if (sk->sk_err) {
            err = -sk->sk_err;

For a blocking connect() the error has already been delivered as
connect()'s return value, so leaving it set causes subsequent operations
like poll()/epoll() to keep reporting POLLERR even though the connect
failure was already delivered.

The error should be consumed once it has been returned to userspace.
Switch to sock_error(), which reads and clears sk_err atomically,
matching the behavior of other protocol implementations such as
__inet_stream_connect().

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Tested-by: Wupeng Ma <mawupeng1@huawei.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com>
Link: https://patch.msgid.link/20260813173024.2362935-4-phind.uet@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/vmw_vsock/af_vsock.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 33928aee05aca..0cbe5a1a40d33 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1671,12 +1671,10 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 	}
 
-	if (sk->sk_err) {
-		err = -sk->sk_err;
+	err = sock_error(sk);
+	if (err) {
 		sk->sk_state = TCP_CLOSE;
 		sock->state = SS_UNCONNECTED;
-	} else {
-		err = 0;
 	}
 
 out_wait:
-- 
2.53.0