What is the authenticity of the hadith: "Whoever eats from this foul-smelling tree should not approach our mosque," and why was it called "foul-smelling" (khabithah) even though it has benefits?

The Hadith is authentic, narrated by Muslim from Abu Sa'id, and in it, the Prophet, peace and blessings be upon him, disliked the smell of garlic but did not prohibit it. He called it "khabithah" (foul/evil) due to the unpleasantness of its odor, not because it is forbidden. It is permissible by consensus, and the prohibition is specific to attending the mosque with this odor.