[PATCH v4 1/4] platform/x86: hp-bioscfg: Simplify return check in hp_add_other_attributes()

[PATCH v4 1/4] platform/x86: hp-bioscfg: Simplify return check in hp_add_other_attributes()

[Harshit Mogalapalli]

All cases in switch-case have a same goto on error, move the return
check out of the switch. This is a cleanup.

Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
v3->v4: Add R.B from Ilpo
---
 drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index 5798b49ddaba..10676e1abc28 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -575,81 +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;
 
 	mutex_lock(&bioscfg_drv.mutex);
 
 	attr_name_kobj = kzalloc(sizeof(*attr_name_kobj), GFP_KERNEL);
 	if (!attr_name_kobj) {
 		ret = -ENOMEM;
 		goto err_other_attr_init;
 	}
 
 	/* 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;
 	}
 
 	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);
-		if (ret)
-			goto err_other_attr_init;
 		break;
 
 	case HPWMI_SURE_START_TYPE:
 		ret = hp_populate_sure_start_data(attr_name_kobj);
-		if (ret)
-			goto err_other_attr_init;
 		break;
 
 	default:
 		ret = -EINVAL;
-		goto err_other_attr_init;
 	}
 
+	if (ret)
+		goto err_other_attr_init;
+
 	mutex_unlock(&bioscfg_drv.mutex);
 	return 0;
 
 err_other_attr_init:
 	mutex_unlock(&bioscfg_drv.mutex);
 	kfree(obj);
 	return ret;
 }
-- 
2.42.0

[PATCH v4 2/4] platform/x86: hp-bioscfg: move mutex_lock() down in hp_add_other_attributes()

[Harshit Mogalapalli]

attr_name_kobj's memory allocation is done with mutex_lock() held, this
is not needed.

Move allocation outside of mutex_lock() so unlock is not needed when
allocation fails.

Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
v3->v4: Add R.B from Ilpo
---
 drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index 10676e1abc28..a3599498c4e8 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -575,79 +575,77 @@ 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;
 
-	mutex_lock(&bioscfg_drv.mutex);
-
 	attr_name_kobj = kzalloc(sizeof(*attr_name_kobj), GFP_KERNEL);
-	if (!attr_name_kobj) {
-		ret = -ENOMEM;
-		goto err_other_attr_init;
-	}
+	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;
 	}
 
 	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:
 	mutex_unlock(&bioscfg_drv.mutex);
 	kfree(obj);
 	return ret;
 }
-- 
2.42.0

[PATCH v4 3/4] platform/x86: hp-bioscfg: Fix error handling in hp_add_other_attributes()

[Harshit Mogalapalli]

'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(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index a3599498c4e8..6ddca857cc4d 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -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;
 }
-- 
2.42.0

[PATCH v4 4/4] platform/x86: hp-bioscfg: Remove unused obj in hp_add_other_attributes()

[Harshit Mogalapalli]

acpi_object *obj is unused in this function, so delete it, also
delete a unnecessary kfree(obj);

Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
 drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index 6ddca857cc4d..8c9f4f3227fc 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -575,80 +575,78 @@ 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;
 		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);
 		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;
 }
 
-- 
2.42.0

Re: [PATCH v4 3/4] platform/x86: hp-bioscfg: Fix error handling in hp_add_other_attributes()

[Ilpo Järvinen]

[-- Attachment #1: Type: text/plain, Size: 3834 bytes --]

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>

-- 
 i.


> ---
>  drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> index a3599498c4e8..6ddca857cc4d 100644
> --- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
> @@ -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;
>  }
> 

Re: [PATCH v4 3/4] platform/x86: hp-bioscfg: Fix error handling in hp_add_other_attributes()

[Hans de Goede]

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

Re: [PATCH v4 3/4] platform/x86: hp-bioscfg: Fix error handling in hp_add_other_attributes()

[Ilpo Järvinen]

[-- Attachment #1: Type: text/plain, Size: 1691 bytes --]

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.

-- 
 i.