As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ACFT WAS CLIMBING THROUGH 13,000 FT, WHEN THE CREW REPORTED SMOKE IN THE COCKPIT AND REQUESTED TO RETURN TO DEPARTURE. THE ACFT LANDED SAFELY BACK ON RUNWAY 23R ABOUT 20 MINUTES AFTER DEPARTURE. OPERATOR CONFIRMED THAT IT WAS RELATED TO A BAD LAVATORY EXHAUST FAN, THE LAVATORY HAS BEEN PLACED UNDER MEL.