Ryan Dunn hasn't even been dead for a day yet -- and film critic Roger Ebert is already ripping the late "Jackass" star for boozing before getting behind the wheel... tweeting, "Friends don't let jackasses drink and drive."
TMZ broke the story ... Dunn's drinking buddy claims Ryan had at least 3 beers and 3 shots before hitting the road in his Porsche.
Source: TMZ