vsock: prevent unnecessary refcnt inc for nonblocking connect

[ Upstream commit c7cd82b90599fa10915f41e3dd9098a77d0aa7b6 ]

Currently vosck_connect() increments sock refcount for nonblocking
socket each time it's called, which can lead to memory leak if
it's called multiple times because connect timeout function decrements
sock refcount only once.

Fixes it by making vsock_connect() return -EALREADY immediately when
sock state is already SS_CONNECTING.

Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Eiichi Tsukata <eiichi.tsukata@nutanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 3e02cc3b24f8a9c19bf4fd92fe0a0d55e5b3bc18..bcc42a901c752e3e98c97c7a1d75ca4c7de2a8c6 100644 (file)
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1322,6 +1322,8 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
                 * non-blocking call.
                 */
                err = -EALREADY;
+               if (flags & O_NONBLOCK)
+                       goto out;
                break;
        default:
                if ((sk->sk_state == TCP_LISTEN) ||