Musnad Ahmad 31:323

Muhammad ibn Ja‘far narrated to us, ‘Awf narrated to us, from Abu al-Siddiq al-Naji, from Abu Sa‘id al-Khudri, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "The Hour will not be established until the earth is filled with oppression and hostility." He said: "Then a man from my lineage—or from my household—will emerge, who will fill it with equity and justice, just as it was filled with oppression and hostility."