As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ONT - ON TAKEOFF REPORTED SMOKE IN CABIN. RETURNED TO ONT AND LANED WITHOUT INCIDENT. FOUND APU OIL LEAK FROM OIL CAP. REINSTALLED CAP AND COALESCER BAGS ON BOTH PACKS. ACCOMPLISHED PACK BURN AND OVERWEIGHT LANDING INSPECTION. SYSTEM GROUND CHECKED NORMAL OPERATION.