Reeky: Smell badly and offensively.
Putrid: In an advanced state of decomposition and having a foul odour.
Putrescent: Becoming putrid.
Fusty: Stale and unclean smelling.
Malodorous: Having an unpleasant smell.
Fetid: Offensively malodorous.
Noisome: Offensively malodorous.
Feculent: Foul with waste matter.