I say, with Allah's guidance: It is permissible for him to wipe over the leather socks, as the condition is met, which is wearing the socks on complete purity at the time of breaking ablution after wearing them. He completed the ablution before anything nullified it. As narrated by Abu Bakrah, may Allah be pleased with him: 'The Prophet, peace be upon him, allowed the traveler three days and nights, and the resident one day and night, if he purified himself and then wore his socks, to wipe over them.' This is found in Sahih Ibn Khuzaymah 1: 96, Sunan Al-Bayhaqi Al-Kubra 1: 281, Sunan Al-Daraqutni 1: 204, and Musnad Al-Bazzar 9: 90. See: Bada'i Al-Sana'i 1: 9, and Allah knows best.