can not set ip type whilelist in ingress annotation

[zjj2wry]

if my annotation set ip not cidr will return error.
nginx.conf :

location / {
            set $proxy_upstream_name "3-mongo-80";
            #the annotation does not contain a valid IP address or network: invalid CIDR address: 192.168.8.104
            return 503;
        }

ingress code:
https://github.com/kubernetes/ingress/blob/master/core/pkg/ingress/annotations/ipwhitelist/main.go#L95

// ParseIPNets parses string slice to IPNet.
func ParseIPNets(specs ...string) (IPNet, error) {
	ipnetset := make(IPNet)
	for _, spec := range specs {
		spec = strings.TrimSpace(spec)
		_, ipnet, err := net.ParseCIDR(spec)
		if err != nil {
			return nil, err
		}
		k := ipnet.String() // In case of normalization
		ipnetset[k] = ipnet
	}
	return ipnetset, nil
}