Opener has 11-15HCP,after RHO's 2♦,he doesnot bid pass or 2NT. IMO,his 2♠-overbid shows spade suit as 4-card with two honors. So, if he has ♠KQxx,♥KQJxx or ♠AQxx,♥KQJxx or ♠AKxx,♥KQJxx, 6♣ or 6♥ or 7♣ is a good contract. But if his ♥-suit is not a semi-Solid suit,6♠ is a good contract. If he has ♠AKQx,♥Kxxxx, 7♠ is a good idea. How about bidding 3♦ to show ♠-fit and wait opener's ♥ or ♠ rebidding?