param_enum: protect against invalid values

Since dev_add_param_enum is passed a pointer containing the actual value
it can contain an invalid value. Protect against it so that we do not
access invalid array elements.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/parameter.c b/lib/parameter.c
index 868b810019..fd05b49adf 100644
--- a/lib/parameter.c
+++ b/lib/parameter.c
@@ -389,7 +389,7 @@ struct param_d *dev_add_param_int(struct device_d *dev, const char *name,
 
 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 @@ static const char *param_enum_get(struct device_d *dev, struct param_d *p)
 	}
 
 	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;
 }