Terms of the contract were not disclosed.
The Knicks also waived forward Omari Spellman on Thursday. Spellman hasn’t appeared in a game this season.
The Knicks had waived Gibson before the season as he was set to make $9.45 million.
Gibson, 35, appeared in 62 games (56 starts) for the Knicks last season, averaging 6.1 points and 4.3 rebounds in 16.5 minutes per game.
Drafted by the Chicago Bulls in the first round (26th overall) of the 2009 NBA draft, he has appeared in 799 games over 11 seasons for the Bulls, Oklahoma City Thunder, Minnesota Timberwolves and Knicks.
He has career averages of 9.5 points and 6.3 rebounds.