The Bengals selected Smith in the sixth round of the 2015 draft. He appeared in 31 games with Cincinnati, making seven tackles, one pass breakup and six special teams tackles.
He played three games this season before the Bengals cut him and re-signed him to their practice squad Nov. 7.
Campbell has appeared in 37 career games with 11 starts for the Browns. He made 15 tackles, one pass breakup and one fumble recovery in eight games this season.
He injured his hamstring in Wednesday’s practice.