What was found
(CAN) CLIMBING THROUGH 18000FT, CSM ADVISED OF SMELL OF SMOKE IN CABIN. EMERGENCY DECENT, A/C RETURNED TO HER(GREECE) PASSENGERS COMMENTED THAT SIDE WALL PANELS AROUND ROW 25 - 30 WERE HOT. T/S REVEALED THAT CLAMP HOLDING APU BLEED DUCT HAD COME LOOSE, ALLOWING HOT AIR INTO THE CARGO HOLD/SIDEWALL AREA. NEW SEALS INSTALLED, CLAMP RE-ATTACHED, LEAK CKECKED OK.