Mishkat al-Masabih 5 Funerals كتاب الجنائز 167

وَعَنِ ابْنِ عَبَّاسٍ قَالَ: جُعِلَ فِي قَبْرِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَطِيفَةٌ حَمْرَاء. رَوَاهُ مُسلم

Ibn ‘Abbas said that a piece of red stuff was put in God’s messenger’s grave. Muslim transmitted it.