What is the ruling on selling mortgaged property when the debt secured by it has not yet been fully recovered?

Primary text

If the debt secured by the mortgage has not been recovered, and the owner has permitted the sale of the property, the possessor sells it, recovers the debt from the price, and gives the remainder in charity. If the owner did not permit the sale, the possessor must refer the matter to the judge (Hakim) so that the judge may sell the property, the possessor may collect his due right from the price, and the remainder is given in charity. Imam Ahmad holds this position.