Hadith 8:3233
Abu Bakr narrated to us, he said: Hatim ibn Isma'il narrated to us, from Ja'far, from his father, who said: Ali said: "Whoever is compelled to [wear] a garment while he is in the state of ihram, and he has nothing but a qaba (a coat or tunic), then let him invert it; he should make its top its bottom, then let him wear it."
حدثنا أبو بكر قال نا حاتم بن إسماعيل عن جعفر عن أبيه قال قال على من اضطر إلى ثوب وهو محرم ولم يكن له إلا قبا فلينكسه يجعل أعلاه أسفله ثم ليلبسه