vhost/test: stop device before reset

[ Upstream commit 245cdd9fbd396483d501db83047116e2530f245f ]

When device stop was moved out of reset, test device wasn't updated to
stop before reset, this resulted in a use after free.  Fix by invoking
stop appropriately.

Fixes: b211616d ("vhost: move -net specific code out")
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/vhost/test.c

@@ -162,6 +162,7 @@ static int vhost_test_release(struct inode *inode, struct file *f)
 
 	vhost_test_stop(n, &private);
 	vhost_test_flush(n);
+	vhost_dev_stop(&n->dev);
 	vhost_dev_cleanup(&n->dev);
 	/* We do an extra flush before freeing memory,
 	 * since jobs can re-queue themselves. */
@@ -238,6 +239,7 @@ static long vhost_test_reset_owner(struct vhost_test *n)
 	}
 	vhost_test_stop(n, &priv);
 	vhost_test_flush(n);
+	vhost_dev_stop(&n->dev);
 	vhost_dev_reset_owner(&n->dev, umem);
 done:
 	mutex_unlock(&n->dev.mutex);