platform/x86: hp-bioscfg: Fix reference leak

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(). Use kobject_put() to dispose the duplicate
attribute in such a case.
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: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg")
Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Jorge Lopez <jorge.lopez2@hp.com>
Link: https://lore.kernel.org/r/20230925142819.74525-3-W_Armin@gmx.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index 8c4f9e1..5798b49 100644 (file)
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -659,7 +659,7 @@ static int hp_init_bios_package_attribute(enum hp_wmi_data_type attr_type,
                                          const char *guid, int min_elements,
                                          int instance_id)
 {
-       struct kobject *attr_name_kobj;
+       struct kobject *attr_name_kobj, *duplicate;
        union acpi_object *elements;
        struct kset *temp_kset;
 
@@ -704,8 +704,11 @@ static int hp_init_bios_package_attribute(enum hp_wmi_data_type attr_type,
        }
 
        /* All duplicate attributes found are ignored */
-       if (kset_find_obj(temp_kset, str_value)) {
+       duplicate = kset_find_obj(temp_kset, str_value);
+       if (duplicate) {
                pr_debug("Duplicate attribute name found - %s\n", str_value);
+               /* kset_find_obj() returns a reference */
+               kobject_put(duplicate);
                goto pack_attr_exit;
        }
 
@@ -768,7 +771,7 @@ static int hp_init_bios_buffer_attribute(enum hp_wmi_data_type attr_type,
                                         const char *guid, int min_elements,
                                         int instance_id)
 {
-       struct kobject *attr_name_kobj;
+       struct kobject *attr_name_kobj, *duplicate;
        struct kset *temp_kset;
        char str[MAX_BUFF_SIZE];
 
@@ -794,8 +797,11 @@ static int hp_init_bios_buffer_attribute(enum hp_wmi_data_type attr_type,
                temp_kset = bioscfg_drv.main_dir_kset;
 
        /* All duplicate attributes found are ignored */
-       if (kset_find_obj(temp_kset, str)) {
+       duplicate = kset_find_obj(temp_kset, str);
+       if (duplicate) {
                pr_debug("Duplicate attribute name found - %s\n", str);
+               /* kset_find_obj() returns a reference */
+               kobject_put(duplicate);
                goto buff_attr_exit;
        }