The deputyship for managing the Waaf and the expenses of the trustee. The trustee can provide his friends and can eat from it reasonably.

Sahih al-Bukhari · Book 40 · Hadith 2313

حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا سُفْيَانُ، عَنْ عَمْرٍو، قَالَ فِي صَدَقَةِ عُمَرَ ـ رضى الله عنه ـ لَيْسَ عَلَى الْوَلِيِّ جُنَاحٌ أَنْ يَأْكُلَ وَيُؤْكِلَ صَدِيقًا ‏{‏لَهُ‏}‏ غَيْرَ مُتَأَثِّلٍ مَالاً، فَكَانَ ابْنُ عُمَرَ هُوَ يَلِي صَدَقَةَ عُمَرَ يُهْدِي لِلنَّاسِ مِنْ أَهْلِ مَكَّةَ، كَانَ يَنْزِلُ عَلَيْهِمْ‏.‏

Narrated `Amr: Concerning the Waqf of `Umar: It was not sinful of the trustee (of the Waqf) to eat or provide his friends from it, provided the trustee had no intention of collecting fortune (for himself). Ibn `Umar was…