A vast number of Sunni scholars have explicitly confirmed the soundness of the “Hadith of al-Ghadir,” with reference to the most famous and well-known versions among them.
“Ibn Hajar al-Asqalani” states regarding this hadith:
“The hadith: ‘Whomever I am his master, Ali is his master,’ has been recorded by ‘al-Tirmidhi’ and ‘al-Nasa’i’ in several different forms, and ‘Ibn Uqdah’ has collected them in a single book; many of its chains of transmission are authentic and correct.” [1]
“Al-Dhahabi,” in “Correcting the Hadith,” states:
“Matlab ibn Ziyad narrates from Abdullah ibn Muhammad ibn Uqayl: ‘I was with Ali ibn al-Husain, Muhammad ibn al-Hanafiyyah, and Abu Jafar at Jabir’s house when a man from Iraq entered and said: I adjure you by Allah to inform me of what you saw and heard from the Messenger of Allah (peace be upon him and his family).'”
He then said:
“We were at Juhfah on the day of al-Ghadir Khumm, and many people from Juhaynah, Muzaynah, and Ghifar were present. Then the Messenger of Allah (peace be upon him and his family) came out of the tent toward us, gestured three times with his hand, took the hand of Amir al-Muminin (peace be upon him), and said: ‘Whomever I am his master, Ali is his master’ (Whomever I am the leader and guardian of, from now on, Ali is his leader and guardian).” [2]
[1] Fath al-Bari, Ibn Hajar, Vol. 7, p. 61.
[2] Siyar A’lam al-Nubala’, al-Dhahabi, Vol. 8, p. 334.