platform/x86: think-lmi: Move kfree(setting->possible_values) to tlmi_attr_setting_re...

We must not free the possible_values string before we have called
sysfs_remove_group(kobj, &tlmi_attr_group) otherwise there is a race
where a sysfs read of possible_values could reference the free-ed
memory.

Move the kfree(setting->possible_values) together with the free of the
actual tlmi_attr_setting struct to avoid this race.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c
index 4cab341..3671b5d 100644 (file)
--- a/drivers/platform/x86/think-lmi.c
+++ b/drivers/platform/x86/think-lmi.c
@@ -626,6 +626,7 @@ static void tlmi_attr_setting_release(struct kobject *kobj)
 {
        struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
 
+       kfree(setting->possible_values);
        kfree(setting);
 }
 
@@ -654,7 +655,6 @@ static void tlmi_release_attr(void)
        /* Attribute structures */
        for (i = 0; i < TLMI_SETTINGS_COUNT; i++) {
                if (tlmi_priv.setting[i]) {
-                       kfree(tlmi_priv.setting[i]->possible_values);
                        sysfs_remove_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group);
                        kobject_put(&tlmi_priv.setting[i]->kobj);
                }