Forte had 17 carries for 82 yards. That equals 4.8 yards per carry.
He had 8 catches for 87 yards. That equals out to 10.9 yards per catch (which isn't a great number).
You are confusing your statistics. I am not terribly worried about either of these numbers however, because that was the game plan. Keep them in front of you, let them have the short stuff, don't give up the big play, then either take it away or hold them to FGs. I'd say the game plan worked exactly as it was designed. After the big 44 yard reception on the Bears first drive, the Bills D did not give up a single play longer than 20 yards.
I'm perfectly fine with giving up 350 yards through the air if we are giving it up at a measly 7 yards per attempt clip and not letting them score touchdowns.