Officers' room in confusion (4)
I believe the answer is:
mess
I believe this clue is a double definition.
'officers' room' is the first definition.
(term for a military canteen)
'confusion' is the second definition.
(mess can mean confusion or chaos)
'in' acts as a link.
(Other definitions for mess that I've seen before include "State of disorder" , "Food-hall" , "4 [DISORDER]" , "Medley" , "Where soldiers may eat" .)