1 files changed, 50 insertions, 28 deletions

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 4c2db6cca557..a9ca9c3b87b3 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -487,12 +487,26 @@ int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
 		goto err;
 	}
 
-	if (vsk->transport) {
-		if (vsk->transport == new_transport) {
-			ret = 0;
-			goto err;
-		}
+	if (vsk->transport && vsk->transport == new_transport) {
+		ret = 0;
+		goto err;
+	}
+
+	/* We increase the module refcnt to prevent the transport unloading
+	 * while there are open sockets assigned to it.
+	 */
+	if (!new_transport || !try_module_get(new_transport->module)) {
+		ret = -ENODEV;
+		goto err;
+	}
 
+	/* It's safe to release the mutex after a successful try_module_get().
+	 * Whichever transport `new_transport` points at, it won't go away until
+	 * the last module_put() below or in vsock_deassign_transport().
+	 */
+	mutex_unlock(&vsock_register_mutex);
+
+	if (vsk->transport) {
 		/* transport->release() must be called with sock lock acquired.
 		 * This path can only be taken during vsock_connect(), where we
 		 * have already held the sock lock. In the other cases, this
@@ -512,20 +526,6 @@ int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
 		vsk->peer_shutdown = 0;
 	}
 
-	/* We increase the module refcnt to prevent the transport unloading
-	 * while there are open sockets assigned to it.
-	 */
-	if (!new_transport || !try_module_get(new_transport->module)) {
-		ret = -ENODEV;
-		goto err;
-	}
-
-	/* It's safe to release the mutex after a successful try_module_get().
-	 * Whichever transport `new_transport` points at, it won't go away until
-	 * the last module_put() below or in vsock_deassign_transport().
-	 */
-	mutex_unlock(&vsock_register_mutex);
-
 	if (sk->sk_type == SOCK_SEQPACKET) {
 		if (!new_transport->seqpacket_allow ||
 		    !new_transport->seqpacket_allow(remote_cid)) {
@@ -1661,18 +1661,40 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
 		timeout = schedule_timeout(timeout);
 		lock_sock(sk);
 
-		if (signal_pending(current)) {
-			err = sock_intr_errno(timeout);
-			sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE;
-			sock->state = SS_UNCONNECTED;
-			vsock_transport_cancel_pkt(vsk);
-			vsock_remove_connected(vsk);
-			goto out_wait;
-		} else if ((sk->sk_state != TCP_ESTABLISHED) && (timeout == 0)) {
-			err = -ETIMEDOUT;
+		/* Connection established. Whatever happens to socket once we
+		 * release it, that's not connect()'s concern. No need to go
+		 * into signal and timeout handling. Call it a day.
+		 *
+		 * Note that allowing to "reset" an already established socket
+		 * here is racy and insecure.
+		 */
+		if (sk->sk_state == TCP_ESTABLISHED)
+			break;
+
+		/* If connection was _not_ established and a signal/timeout came
+		 * to be, we want the socket's state reset. User space may want
+		 * to retry.
+		 *
+		 * sk_state != TCP_ESTABLISHED implies that socket is not on
+		 * vsock_connected_table. We keep the binding and the transport
+		 * assigned.
+		 */
+		if (signal_pending(current) || timeout == 0) {
+			err = timeout == 0 ? -ETIMEDOUT : sock_intr_errno(timeout);
+
+			/* Listener might have already responded with
+			 * VIRTIO_VSOCK_OP_RESPONSE. Its handling expects our
+			 * sk_state == TCP_SYN_SENT, which hereby we break.
+			 * In such case VIRTIO_VSOCK_OP_RST will follow.
+			 */
 			sk->sk_state = TCP_CLOSE;
 			sock->state = SS_UNCONNECTED;
+
+			/* Try to cancel VIRTIO_VSOCK_OP_REQUEST skb sent out by
+			 * transport->connect().
+			 */
 			vsock_transport_cancel_pkt(vsk);
+
 			goto out_wait;
 		}