Make naming consistent with regexp.MatchString

internal/pkg/image/util.go

@@ -12,7 +12,7 @@ import (
 )
 
 func ValidName(name string) bool {
-	if !util.ValidString(name, "^[\\w\\-\\.\\:]+$") {
+	if !util.ValidString("^[\\w\\-\\.\\:]+$", name) {
 		wwlog.Warn("Image name has illegal characters: %s", name)
 		return false
 	}

internal/pkg/overlay/overlay.go

@@ -961,7 +961,7 @@ func BuildOverlayIndir(nodeData node.Node, allNodes []node.Node, overlayNames []
 		return fmt.Errorf("output must a be a directory: %s", outputDir)
 	}
 
-	if !util.ValidString(strings.Join(overlayNames, ""), "^[a-zA-Z0-9-._:]+$") {
+	if !util.ValidString("^[a-zA-Z0-9-._:]+$", strings.Join(overlayNames, "")) {
 		return fmt.Errorf("overlay names contains illegal characters: %v", overlayNames)
 	}
 

internal/pkg/upgrade/util.go

@@ -27,7 +27,7 @@ func legacyKernelVersionFile(kernelName string) string {
 		return ""
 	}
 
-	if !util.ValidString(kernelName, "^[a-zA-Z0-9-._]+$") {
+	if !util.ValidString("^[a-zA-Z0-9-._]+$", kernelName) {
 		return ""
 	}
 

internal/pkg/util/util.go

@@ -129,8 +129,8 @@ func ReadFile(path string) ([]string, error) {
 	return lines, nil
 }
 
-func ValidString(pattern string, expr string) bool {
-	if b, _ := regexp.MatchString(expr, pattern); b {
+func ValidString(pattern string, s string) bool {
+	if b, _ := regexp.MatchString(pattern, s); b {
 		return true
 	}
 	return false