hwmon: (pmbus) Fix krealloc() misuse in pmbus_add_attribute()

If krealloc() returns NULL, it *doesn't* free the original. So any code
of the form 'foo = krealloc(foo, …);' is almost certainly a bug.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 80eef50..9add609 100644 (file)
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -766,12 +766,14 @@ static ssize_t pmbus_show_label(struct device *dev,
 static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
 {
        if (data->num_attributes >= data->max_attributes - 1) {
-               data->max_attributes += PMBUS_ATTR_ALLOC_SIZE;
-               data->group.attrs = krealloc(data->group.attrs,
-                                            sizeof(struct attribute *) *
-                                            data->max_attributes, GFP_KERNEL);
-               if (data->group.attrs == NULL)
+               int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE;
+               void *new_attrs = krealloc(data->group.attrs,
+                                          new_max_attrs * sizeof(void *),
+                                          GFP_KERNEL);
+               if (!new_attrs)
                        return -ENOMEM;
+               data->group.attrs = new_attrs;
+               data->max_attributes = new_max_attrs;
        }
 
        data->group.attrs[data->num_attributes++] = attr;