As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 7796 - IAD-BUF - LAVATORY SMOKE WENT OFF. WHILE INSPECTING THE LAVATORY, SMOKE WAS SEEN COMING FROM CEILING AREA. PERFORMED VISUAL INSPECTION OF AIRCRAFT AND FOUND NO TRACES OF BURNED WIRES OR ANY SIGNS OF BURNING. AIRCRAFT OK TO CONTINUE SERVICE.