Sahih Muslim Book 27, Hadith 43
A mention of Allah's Messenger (ﷺ) observing 'Umra from ja'rina was made before Ibn 'Umar. He said: He did not enter into the state of Ihram from that (place), and Umar had taken a vow of observing I'tikaf for a night during the days of Ignorance. The rest of the hadith is the same.
When Allah's Apostle (ﷺ) came back from the Battle of Hunain, Umar asked Allah's Messenger (ﷺ) about the vow he had taken during the days of Ignorance that he would observe I'tikaf for a day. The rest of the hadith is the same.
This hadith has been transmitted on the authority of Ibn Umar through another chain of transmitters but with a slight variation of words.