um: virtio_uml: fix memory leak on init failures

If initialization fails, e.g. because the connection failed,
we leak the 'vu_dev'. Fix that. Reported by smatch.

Fixes: 5d38f32 ("um: drivers: Add virtio vhost-user driver")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/drivers/virtio_uml.c

@@ -1140,7 +1140,7 @@ static int virtio_uml_probe(struct platform_device *pdev)
 		rc = os_connect_socket(pdata->socket_path);
 	} while (rc == -EINTR);
 	if (rc < 0)
-		return rc;
+		goto error_free;
 	vu_dev->sock = rc;
 
 	spin_lock_init(&vu_dev->sock_lock);
@@ -1161,6 +1161,8 @@ static int virtio_uml_probe(struct platform_device *pdev)
 
 error_init:
 	os_close_file(vu_dev->sock);
+error_free:
+	kfree(vu_dev);
 	return rc;
 }