Garlic is alright to give your dogs, provided you aren't giving them like 2 full garlic bulbs! ( I think that would make even us sick).
In small amounts it can actually be good for the dog. I usually give Jr garlic when he has fleas with no bad side effects.
Its onions that you have to worry about. Since onions and garlics are in the same plant family people tend to be wary of both though.