platform/x86: think-lmi: Fix memory leak when showing current settings

[ Upstream commit a3c4c053014585dcf20f4df954791b74d8a8afcd ]

When retriving a item string with tlmi_setting(), the result has to be
freed using kfree(). In current_value_show() however, malformed
item strings are not freed, causing a memory leak.
Fix this by eliminating the early return responsible for this.

Reported-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Link: https://lore.kernel.org/platform-driver-x86/01e920bc-5882-ba0c-dd15-868bf0eca0b8@alu.unizg.hr/T/#t
Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Fixes: 0fdf10e5fc96 ("platform/x86: think-lmi: Split current_value to reflect only the value")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20230331213319.41040-1-W_Armin@gmx.de
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c
index 74af3e593b2ca08e3e7b5626f2273f08df55ca11..4e738ec5e6fb8beac35c09887d6c526cb9edfbe9 100644 (file)
--- a/drivers/platform/x86/think-lmi.c
+++ b/drivers/platform/x86/think-lmi.c
@@ -930,10 +930,12 @@ static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *a
        /* validate and split from `item,value` -> `value` */
        value = strpbrk(item, ",");
        if (!value || value == item || !strlen(value + 1))
-               return -EINVAL;
+               ret = -EINVAL;
+       else
+               ret = sysfs_emit(buf, "%s\n", value + 1);
 
-       ret = sysfs_emit(buf, "%s\n", value + 1);
        kfree(item);
+
        return ret;
 }