Check for more invalid cidr syntax

salt/common/tools/sbin/so-common

@@ -392,6 +392,8 @@ has_uppercase() {
 valid_cidr() {
 	# Verify there is a backslash in the string
 	echo "$1" | grep -qP "^[^/]+/[^/]+$" || return 1
+
+	valid_ip4_cidr_mask "$1" && return 0 || return 1
 	
 	local cidr="$1"
 	local ip