White gas (or coleman fuel) smells like white gas. Yes, it can have a smell. White gas is a liquid at room temperature, you have to wait for every last drop of liquid to evaporate to remove all smell. The human nose can smell most petroleum fuels down into the single digit parts per million range.

Butane is a gas at room temperature. All of my butane stoves (I have several) are designed to only have butane in the vapor phase within the stove, thus it would be almost impossible for any smell to exist after it has been removed from the canister for a while. For this post where I refer to butane, I am considering that to also apply to iso-butane or butane/propane mixtures.