diff --git a/lib/parameter.c b/lib/parameter.c
index 868b810..fd05b49 100644
--- a/lib/parameter.c
+++ b/lib/parameter.c
@@ -389,7 +389,7 @@
 
 struct param_enum {
 	struct param_d param;
-	int *value;
+	unsigned int *value;
 	const char * const *names;
 	int num_names;
 	int (*set)(struct param_d *p, void *priv);
@@ -441,7 +441,11 @@
 	}
 
 	free(p->value);
-	p->value = strdup(pe->names[*pe->value]);
+
+	if (*pe->value >= pe->num_names)
+		p->value = asprintf("invalid:%d", *pe->value);
+	else
+		p->value = strdup(pe->names[*pe->value]);
 
 	return p->value;
 }