Smith is set to make his 150th League appearance for United.
Gary Kelly (back) and Jermaine Pennant (personal problems) are available and Stephen McPhail is in the squad after a loan spell at Nottingham Forest.
Scott Parker, who has also completed a suspension, and Claus Jensen, fit again after injury, are set to return for Charlton.
Jonatan Johansson will face a late fitness check after a thigh strain.
Leeds (from): Robinson, Kelly, Harte, Matteo, Radebe, Morris, Camara, Barmby, Bridges, Viduka, Pennant, Chapuis, Wilcox, Johnson, Duberry, Batty, Olembe, McPhail, Lennon, Domi, Milner, Carson.
Charlton (from): Kiely, Hreidarsson, Fish, Svensson, Holland, Perry, Fortune, Kishishev, Euell, Di Canio Lisbie, Stuart, Parker, Jensen, Powell, Cole, Hughes, Royce.