Musannaf Ibn Abi Shayba 13:3342

Abu Bakr narrated to us, he said: Abbad ibn al-Awwam narrated to us, from Abd al-Malik, from Ata’, that he was asked about a man who rented camels, then he rented them out for more than that. He hesitated for a moment, then said: "I do not see any harm in it, in my opinion."