Kid Cudi, as posted here a couple months ago, said he is no longer smoking drugs.
"This is not a joke. I know most of you wanna see me all drugged out and fucked up and i know misery loves company, but im sorry those days are over. I had a good run, Amsterdam and all. Im happy being sober. Im happy being a new me. Giva fuck who thinks of me different, you didnt care about me in the first place if you cant be proud and happy for me for growing and starting a new chapter. Im not your puppet or your tap dancing drug addict here to be your miserable muse, i always made music for me to help myself find understanding. I have finally learned from the words in my songs. I love who loves me and who really cares about me."
Clearly, Ganja is a grey area.