From: Hans de Goede <hdegoede@xxxxxxxxxx>
[ Upstream commit d939cd96b9df6dcde1605fab23bbd6307e11f930 ]
On some system the WMI GUIDs used by dell-wmi-sysman are present but there
are no enum type attributes, this causes init_bios_attributes() to return
-ENODEV, after which sysman_init() does a "goto fail_create_group" and then
calls release_attributes_data().
release_attributes_data() calls kset_unregister(wmi_priv.main_dir_kset);
but before this commit it was missing a "wmi_priv.main_dir_kset = NULL;"
statement; and after calling release_attributes_data() the sysman_init()
error handling does this:
if (wmi_priv.main_dir_kset) {
kset_unregister(wmi_priv.main_dir_kset);
wmi_priv.main_dir_kset = NULL;
}
Which causes a second kset_unregister(wmi_priv.main_dir_kset), leading to
a double-free, which causes a crash.
Add the missing "wmi_priv.main_dir_kset = NULL;" statement to
release_attributes_data() to fix this double-free crash.
Fixes: e8a60aa7404b ("platform/x86: Introduce support for Systems Management Driver over WMI for Dell Systems")
Cc: Divya Bharathi <Divya_Bharathi@xxxxxxxx>
Cc: Mario Limonciello <mario.limonciello@xxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210321115901.35072-2-hdegoede@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/platform/x86/dell-wmi-sysman/sysman.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/platform/x86/dell-wmi-sysman/sysman.c b/drivers/platform/x86/dell-wmi-sysman/sysman.c
index cb81010ba1a2..c1997db74cca 100644
--- a/drivers/platform/x86/dell-wmi-sysman/sysman.c
+++ b/drivers/platform/x86/dell-wmi-sysman/sysman.c
@@ -388,6 +388,7 @@ static void release_attributes_data(void)
if (wmi_priv.main_dir_kset) {
destroy_attribute_objs(wmi_priv.main_dir_kset);
kset_unregister(wmi_priv.main_dir_kset);
+ wmi_priv.main_dir_kset = NULL;
}
mutex_unlock(&wmi_priv.mutex);
--
2.30.1
