Fiqh-us-Sunnah Volume 5, Hajj and ‘Umrah, Fiqh 5.046B.

Abdullah ibn ‘Amer reported: “‘Umar used to throw a piece of leather on a tree and sit under its shade while he was in the state of ihram.” This is reported by Ibn Abi Shaiba.

Ummul-Hussain reported: “I performed the Farewell Hajj with the Prophet (peace be upon him). I saw Usamah ibn Zaid and Bilal. One of them was holding the noseband of the Prophet’s she-camel, and the other was shading him with a cloth from the sun until he threw the pebbles at ‘Aqabah.” This is reported by Ahmad and Muslim. ‘Ata said: “A muhrim may shade himself from the sun, and take shelter to protect himself from rain and wind.” Ibrahim An-Nakh’i reported: “Al-Aswad ibn Yazid threw a cloth over his head for shelter from rain while he was in the state of ihram.”