code: func validateLocalNonReservedPath(targetPath string, fldPath *field.Path) field.ErrorList {
  	allErrs := field.ErrorList{}
  	allErrs = append(allErrs, validateLocalDescendingPath(targetPath, fldPath)...)
  	// Don't report this error if the check for .. elements already caught it.
  	if strings.HasPrefix(targetPath, "..") && !strings.HasPrefix(targetPath, "../") {
  		allErrs = append(allErrs, field.Invalid(fldPath, targetPath, "must not start with '..'"))
  	}
  	return allErrs
  }
docs: // This validate will make sure targetPath:
  // 1. is not abs path
  // 2. does not contain any '..' elements
  // 3. does not start with '..'