Johnson traveled to California following the death of his mother last weekend, and Williams was injured in last Sunday's win against the Jacksonville Jaguars.
"Aaron Williams loves football," Bills coach Doug Marrone said. "For that kid to be hurting, I mean he has ... I don't know if anybody has ever had that injury. I have. That's probably one of the most painful."
Meanwhile, Marrone said tight end Tony Moeaki, who has been inactive in two games since signing with Buffalo, will be active Sunday.
WR Stevie Johnson (personal; did not participate)
QB EJ Manuel (knee; did not participate)
S Aaron Williams (ribs; did not participate)
DT Marcell Dareus (ankle; full participation)
RB Fred Jackson (ribs; full participation)
CB Brandon Smith (ankle; full participation)
DT Kyle Williams (Achilles; full participation)