וַיִּמְצָ֨א יוֹסֵ֥ף חֵ֛ן בְּעֵינָ֖יו וַיְשָׁ֣רֶת אֹת֑וֹ וַיַּפְקִדֵ֙הוּ֙ עַל־בֵּית֔וֹ וְכָל־יֶשׁ־ל֖וֹ נָתַ֥ן בְּיָדֽוֹ׃
et Joseph trouva faveur à ses yeux et il devint son serviteur; Putiphar le mit à la tête de sa maison et lui confia tout son avoir.
Rashi on Genesis
וכל יש לו AND ALL THAT HE HAD — This is an elliptical phrase — the word אשר is omitted after.
Sforno on Genesis
וישרת אותו, he attended to his master’s bodily needs.
Radak on Genesis
וימצא.יוסף חן...וישרת אותו, because Joseph had found so much favour in his eyes he appointed him as his exclusive personal valet. At the same time he appointed him in charge so that without Joseph’s approval nothing could be done within this household.