Osama bin NAUGHTY -- Porn Found In Hideout

Apparently, Osama bin Laden had no problem keeping himself busy in his terror compound in Pakistan ... 'cause the Navy SEALS who killed his ass reportedly found a TON of porn in that place.

According to Reuters, the commandos found a porn "stash" inside Osama's lair -- which included, "electronically recorded video and is fairly extensive."

Dirty.