This is more serious than just an annoying smell, I'd highly recommend bringing your vehicle in to your Kia Service center soon. We all know gasoline is highly volatile and the vapors are highly flammable, explosive and are not healthy to breath.
You could have a problem with your Evap. Control Canister, or a leak somewhere in the fuel system. Regardless, you should not be driving a vehicle if you smell obvious gasoline fumes in the cabin. The dealer will be able to test for and diagnose the problem quickly and easily.
And no, you shouldn't rely on your cabin dust filter to remove gasoline vapors, it was not designed to remove vapors and gasses, and this would just be masking an underlying problem that needs to be dealt with by your mechanic/Service shop.