Chris Brown -- Took Rehab Break ... To Party His Face Off

Chris Brown made a little pit stop on his way back to rehab Sunday -- after visiting his lawyer -- he dropped by Trey Songz' blowout Super Bowl party ... filled with girls and booze ... and it's possible the shindig could land Chris in some hot water.

Brown was given a pass out of rehab Sunday specifically to meet with his attorney, Mark Geragos, for the singer's court hearing the next day.

After the meeting, Chris decided it would be fun to enjoy a few Super Bowl moments with his pal Trey Songz. There was nothing in the rehab pass indicating partying with chicks and booze was ok.

Sources close to Chris tell TMZ, he was only there for around 10 minutes ... and only because he thought the party was for charity. We can't help but call BS. There's no evidence there was any fundraising going on, and even if there was ... it's irrelevant.

Our Chris sources say he didn't drink and was monitored by a rehab worker at the party.

Calls to Chris' reps weren't returned.