[v4,3/4] platform/x86: hp-bioscfg: Fix error handling in hp_add_other_attributes()
Commit Message
'attr_name_kobj' is allocated using kzalloc, but on all the error paths
it is not freed, hence we have a memory leak.
Fix the error path before kobject_init_and_add() by adding kfree().
kobject_put() must be always called after passing the object to
kobject_init_and_add(). Only the error path which is immediately next
to kobject_init_and_add() calls kobject_put() and not any other error
path after it.
Fix the error handling after kobject_init_and_add() by moving the
kobject_put() into the goto label err_other_attr_init that is already
used by all the error paths after kobject_init_and_add().
Fixes: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202309201412.on0VXJGo-lkp@intel.com/
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
---
This is based on static analysis, only compile tested.
v3->v4: Add more explicit statement on how we are fixing it, suggested
by Ilpo
---
drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
Comments
On Mon, 13 Nov 2023, Harshit Mogalapalli wrote:
> 'attr_name_kobj' is allocated using kzalloc, but on all the error paths
> it is not freed, hence we have a memory leak.
>
> Fix the error path before kobject_init_and_add() by adding kfree().
>
> kobject_put() must be always called after passing the object to
> kobject_init_and_add(). Only the error path which is immediately next
> to kobject_init_and_add() calls kobject_put() and not any other error
> path after it.
>
> Fix the error handling after kobject_init_and_add() by moving the
> kobject_put() into the goto label err_other_attr_init that is already
> used by all the error paths after kobject_init_and_add().
>
> Fixes: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg")
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <error27@gmail.com>
> Closes: https://lore.kernel.org/r/202309201412.on0VXJGo-lkp@intel.com/
> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
> ---
> This is based on static analysis, only compile tested.
>
> v3->v4: Add more explicit statement on how we are fixing it, suggested
> by Ilpo
Thanks a lot, this looks fine too now.
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Hi Ilpo,
On 11/14/23 11:31, Ilpo Järvinen wrote:
> On Mon, 13 Nov 2023, Harshit Mogalapalli wrote:
>
>> 'attr_name_kobj' is allocated using kzalloc, but on all the error paths
>> it is not freed, hence we have a memory leak.
>>
>> Fix the error path before kobject_init_and_add() by adding kfree().
>>
>> kobject_put() must be always called after passing the object to
>> kobject_init_and_add(). Only the error path which is immediately next
>> to kobject_init_and_add() calls kobject_put() and not any other error
>> path after it.
>>
>> Fix the error handling after kobject_init_and_add() by moving the
>> kobject_put() into the goto label err_other_attr_init that is already
>> used by all the error paths after kobject_init_and_add().
>>
>> Fixes: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg")
>> Reported-by: kernel test robot <lkp@intel.com>
>> Reported-by: Dan Carpenter <error27@gmail.com>
>> Closes: https://lore.kernel.org/r/202309201412.on0VXJGo-lkp@intel.com/
>> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
>> ---
>> This is based on static analysis, only compile tested.
>>
>> v3->v4: Add more explicit statement on how we are fixing it, suggested
>> by Ilpo
>
> Thanks a lot, this looks fine too now.
>
> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Thank you for reviewing this series. I believe that it is best
to submit this as fixes for the current cycle.
Under the assumption that you agree with this I've delegated
these 4 patches to you (Ilpo) in patchwork.
Regards,
Hans
On Tue, 14 Nov 2023, Hans de Goede wrote:
> On 11/14/23 11:31, Ilpo Järvinen wrote:
> > On Mon, 13 Nov 2023, Harshit Mogalapalli wrote:
> >
> >> 'attr_name_kobj' is allocated using kzalloc, but on all the error paths
> >> it is not freed, hence we have a memory leak.
> >>
> >> Fix the error path before kobject_init_and_add() by adding kfree().
> >>
> >> kobject_put() must be always called after passing the object to
> >> kobject_init_and_add(). Only the error path which is immediately next
> >> to kobject_init_and_add() calls kobject_put() and not any other error
> >> path after it.
> >>
> >> Fix the error handling after kobject_init_and_add() by moving the
> >> kobject_put() into the goto label err_other_attr_init that is already
> >> used by all the error paths after kobject_init_and_add().
> >>
> >> Fixes: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg")
> >> Reported-by: kernel test robot <lkp@intel.com>
> >> Reported-by: Dan Carpenter <error27@gmail.com>
> >> Closes: https://lore.kernel.org/r/202309201412.on0VXJGo-lkp@intel.com/
> >> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
> >> ---
> >> This is based on static analysis, only compile tested.
> >>
> >> v3->v4: Add more explicit statement on how we are fixing it, suggested
> >> by Ilpo
> >
> > Thanks a lot, this looks fine too now.
> >
> > Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
>
> Thank you for reviewing this series. I believe that it is best
> to submit this as fixes for the current cycle.
>
> Under the assumption that you agree with this I've delegated
> these 4 patches to you (Ilpo) in patchwork.
Yes, I'll take care of it later this week.
@@ -575,77 +575,79 @@ static void release_attributes_data(void)
/**
* hp_add_other_attributes() - Initialize HP custom attributes not
* reported by BIOS and required to support Secure Platform and Sure
* Start.
*
* @attr_type: Custom HP attribute not reported by BIOS
*
* Initialize all 2 types of attributes: Platform and Sure Start
* object. Populates each attribute types respective properties
* under sysfs files.
*
* Returns zero(0) if successful. Otherwise, a negative value.
*/
static int hp_add_other_attributes(int attr_type)
{
struct kobject *attr_name_kobj;
union acpi_object *obj = NULL;
int ret;
char *attr_name;
attr_name_kobj = kzalloc(sizeof(*attr_name_kobj), GFP_KERNEL);
if (!attr_name_kobj)
return -ENOMEM;
mutex_lock(&bioscfg_drv.mutex);
/* Check if attribute type is supported */
switch (attr_type) {
case HPWMI_SECURE_PLATFORM_TYPE:
attr_name_kobj->kset = bioscfg_drv.authentication_dir_kset;
attr_name = SPM_STR;
break;
case HPWMI_SURE_START_TYPE:
attr_name_kobj->kset = bioscfg_drv.main_dir_kset;
attr_name = SURE_START_STR;
break;
default:
pr_err("Error: Unknown attr_type: %d\n", attr_type);
ret = -EINVAL;
- goto err_other_attr_init;
+ kfree(attr_name_kobj);
+ goto unlock_drv_mutex;
}
ret = kobject_init_and_add(attr_name_kobj, &attr_name_ktype,
NULL, "%s", attr_name);
if (ret) {
pr_err("Error encountered [%d]\n", ret);
- kobject_put(attr_name_kobj);
goto err_other_attr_init;
}
/* Populate attribute data */
switch (attr_type) {
case HPWMI_SECURE_PLATFORM_TYPE:
ret = hp_populate_secure_platform_data(attr_name_kobj);
break;
case HPWMI_SURE_START_TYPE:
ret = hp_populate_sure_start_data(attr_name_kobj);
break;
default:
ret = -EINVAL;
}
if (ret)
goto err_other_attr_init;
mutex_unlock(&bioscfg_drv.mutex);
return 0;
err_other_attr_init:
+ kobject_put(attr_name_kobj);
+unlock_drv_mutex:
mutex_unlock(&bioscfg_drv.mutex);
kfree(obj);
return ret;
}