A homeless Oklahoma man was facing a long stint in the slammer all because of a mistake made on a drug test.

Cody Gregg was busted in August for riding his bike without a light. When cops searched his backpack, they found a coffee can and a bag of white powder, which was said to have been cocaine by the field test.

The 29-year-old was charged with felony drug trafficking and spent two months in the Oklahoma County Jail before he got sentenced to 15 years in prison.

But it turns out that lab results determined the substance was actually powdered milk and Gregg was set free last week.