What is the ruling on one making up a fast (qadaa') who slept in a state of janabah and did not perform ghusl until after the Fajr adhan? Is his fasting valid?

The fast of one who wakes up in a state of major ritual impurity (junub) is valid. Many hadiths indicate this, among them the hadith of Aisha: "A man said: 'O Messenger of Allah, I am overtaken by prayer while I am in a state of ritual impurity, so I fast.' The Messenger of Allah (peace and blessings be upon him and his family) said: 'And I am overtaken by prayer while I am in a state of ritual impurity, so I fast.'" And the hadith of Aisha and Umm Salama: "The Prophet (peace and blessings be upon him and his family) used to wake up in a state of major ritual impurity due to intercourse—not a wet dream—and then fast in Ramadan." The scholars have unanimously agreed on the validity of the fast of one who is in a state of major ritual impurity.