Ice Cube Photog -- 'Raiders' Tees Are Straight Outta Line

Ice Cube and Forever 21 are not only a totally unexpected pairing, it's an illegal one -- according to the guy who says the retail giant ripped off his pic of the rapper to make a buck.

The t-shirts in question show Cube's snarling face slapped on a mocked up Oakland Raiders logo. Perfect for that 20-something chick who's just dying to rep old school rap and the silver and black ... right?

Patrick Hoelck says not so fast. He's the photographer who took the famous pic of Ice Cube used on the t-shirt, and he says Forever 21, and another merch company called Control ... never got his permission.

In the lawsuit he just filed ... Hoelck says he sent both companies letters back in June demanding they yank the shirts. They didn't, so now he wants a jury to shut 'em down, and award him their profits.