Should one who prayed with short socks upon which he wiped perform ablution and repeat his prayer?

For wiping over socks (khuffayn) to be permissible, the socks must cover the area of obligation (the feet up to the ankles). If the socks are short and do not cover the area of obligation, then wiping over them is not sufficient, and consequently, the prayer is invalid and must be repeated, because it was performed with an incomplete ablution. It is not necessary to repeat the entire ablution if nothing else has nullified it; rather, it is sufficient to wash the feet, based on the view that continuity (muwalat) is not a condition for ablution.