What is the legality of using popular music in indie movies?

right, so I'm an aspiring movie writer/director, and my friends and I have been working on a movie. The soundtrack is made up of alot of popular songs, but were covered by my friend's band. If a song is redone, is it still a licence infringement if we were to produce the movie and enter it in competitions or if we were to sell the movie on dvd (hypothetically)? If not, could someone please clarify what would be legal along the lines of using music? Please don't give me those "do whatever you want" answers, I really need a serious answer. Thanks in Advance.