Terms of the deal announced Monday were not disclosed.
The 33-year-old Hall has played 10 NFL seasons, including three in St. Louis. He spent his first seven seasons in Detroit.
Hall started 14 games in 2009 and was third on the Rams with 4.5 sacks. He also had 59 tackles, eight quarterback hits, five pressures and two tackles for loss.
Hall has 46.5 career sacks in 134 games and led St. Louis with 6.5 sacks in 2008. His career-best was 11.5 sacks for the Lions in 2004.