Can 吃的人 mean both a person who eats something and a person who someone eats? Can 吃的人 mean both a person who eats something and a person who someone eats?
If a subject or a object is omitted.
In the right context, '吃的人‘ can mean 'the person who we are eating'.

Reminds me of that old joke:

2 cannibals are eating a clown, one says to the other, "Does this clown taste funny to you?"

两个食人族正在吃一个小丑，其中一个问另一个：“我们吃的这个小丑，味道有趣吗？”

Very funny in English, not so sure in Chinese， humour does not translate well!