Umar asked the Prophet ﷺ, "Can one of us sleep while in a state of major ritual impurity?"He replied, "Yes, and let him perform ablution as he would for prayer."Nafi said that whenever Ibn Umar wished to do something of that sort, he would perform ablution as he would for prayer, except for his feet.
حدثنا عبد الرزاق حدثنا عبيد الله بن عمر عن نافع
أن عمر سأل النبي ﷺ هل ينام أحدنا وهو جنب فقال نعم ويتوضأ وضوءه للصلاة قال نافع فكان ابن عمر إذا أراد أن يفعل شيئا من ذلك توضأ وضوءه للصلاة ما خلا رجليه
Its isnad is sahih, and it is a repetition of 4662. It has already passed in the Musnad of Umar at 235 with this same isnad, but here there is an addition, the account of what Ibn Umar did.