static struct ion_handle *ion_handle_get_by_id(struct ion_client *client,
						int id)
{
	struct ion_handle *handle;

	mutex_lock(&client->lock);
	handle = idr_find(&client->idr, id);
	if (handle)
		ion_handle_get(handle);
	mutex_unlock(&client->lock);

	return handle ? handle : ERR_PTR(-EINVAL);
}
Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.