If a duplicate attribute is found using kset_find_obj(), a reference
to that attribute is returned which needs to be disposed accordingly
using kobject_put(). Move the setting name validation into a separate
function to allow for this change without having to duplicate the
cleanup code for this setting.
As a side note, a very similar bug was fixed in
commit 7295a996fdab ("platform/x86: dell-sysman: Fix reference leak"),
so it seems that the bug was copied from that driver.
Compile-tested only.
Fixes: 1bcad8e510b2 ("platform/x86: think-lmi: Fix issues with duplicate attributes")
Reviewed-by: Mark Pearson <mpearson-lenovo@xxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
---
Changes in v4:
- add another Reviewed-by
Changes in v3:
- add Reviewed-by
Changes in v2:
- no changes
---
drivers/platform/x86/think-lmi.c | 24 ++++++++++++++++++++----
1 file changed, 20 insertions(+), 4 deletions(-)
diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c
index 4be6f28d4600..3a396b763c49 100644
--- a/drivers/platform/x86/think-lmi.c
+++ b/drivers/platform/x86/think-lmi.c
@@ -1344,6 +1344,24 @@ static void tlmi_release_attr(void)
kset_unregister(tlmi_priv.authentication_kset);
}
+static int tlmi_validate_setting_name(struct kset *attribute_kset, char *name)
+{
+ struct kobject *duplicate;
+
+ if (!strcmp(name, "Reserved"))
+ return -EINVAL;
+
+ duplicate = kset_find_obj(attribute_kset, name);
+ if (duplicate) {
+ pr_debug("Duplicate attribute name found - %s\n", name);
+ /* kset_find_obj() returns a reference */
+ kobject_put(duplicate);
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
static int tlmi_sysfs_init(void)
{
int i, ret;
@@ -1372,10 +1390,8 @@ static int tlmi_sysfs_init(void)
continue;
/* check for duplicate or reserved values */
- if (kset_find_obj(tlmi_priv.attribute_kset, tlmi_priv.setting[i]->display_name) ||
- !strcmp(tlmi_priv.setting[i]->display_name, "Reserved")) {
- pr_debug("duplicate or reserved attribute name found - %s\n",
- tlmi_priv.setting[i]->display_name);
+ if (tlmi_validate_setting_name(tlmi_priv.attribute_kset,
+ tlmi_priv.setting[i]->display_name) < 0) {
kfree(tlmi_priv.setting[i]->possible_values);
kfree(tlmi_priv.setting[i]);
tlmi_priv.setting[i] = NULL;
--
2.39.2
