In a regular deep freeze that doesn't have a defrost cycle - easily a year or more (as long as it's packaged well).
In a frost free type, even if it's packaged well, a few months tops. I don't keep meat in our fridge freezer as it's a frost free, so I can't say for sure. The defrosting cycle will thaw the top bit of meat and refreeze it over and over, and freezerburn is inevitable after a few months. That's where you end up with funky meat (and anything else that is in there for a couple months).