(5) باب صفة الحج ودخول مكة
Ibn 'Umar (RAA) narrated that 'Al-'Abbas bin 'Abdul Muttalib asked permission from the Prophet (ﷺ) to stay at Makkah during the nights of Mina in order to provide drinking water (from Zamzam) to the pilgrims, and the Prophet (ﷺ) allowed him.' Agreed Upon.
Reference: Bulugh al-Maram 770
In-book reference: Book 6, Hadith 62
English translation: Book 6, Hadith 789