static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
		const struct ipc_ops *ops, struct ipc_params *params)
{
	int err;

	down_write(&ids->rwsem);
	err = ops->getnew(ns, params);
	up_write(&ids->rwsem);
	return err;
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.