The Commissioner, within the applicable period of limitations, may credit any overpayment of tax, including interest thereon, against any outstanding liability for any tax (or for any interest, additional amount, addition to the tax, or assessable penalty) owed by the person making the overpayment and the balance, if any, shall be refunded, subject to sections 6402 (c) and (d) and the regulations thereunder, to that person by the Commissioner.