[PATCH v2] kobject: Restore old behaviour of kobject_del(NULL)

[PATCH v2] kobject: Restore old behaviour of kobject_del(NULL)

[Andy Shevchenko]

The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in
kobject_cleanup()") inadvertently dropped a possibility to call kobject_del()
with NULL pointer. Restore the old behaviour.

Fixes: 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in kobject_cleanup()")
Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v2: replaced ?: with plain conditional (Greg)
 lib/kobject.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/kobject.c b/lib/kobject.c
index 3afb939f2a1c..9dce68c378e6 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -637,8 +637,12 @@ static void __kobject_del(struct kobject *kobj)
  */
 void kobject_del(struct kobject *kobj)
 {
-	struct kobject *parent = kobj->parent;
+	struct kobject *parent;
+
+	if (!kobj)
+		return;
 
+	parent = kobj->parent;
 	__kobject_del(kobj);
 	kobject_put(parent);
 }
-- 
2.27.0

Re: [PATCH v2] kobject: Restore old behaviour of kobject_del(NULL)

[Qu Wenruo]

On 2020/8/3 下午4:27, Andy Shevchenko wrote:
> The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in
> kobject_cleanup()") inadvertently dropped a possibility to call kobject_del()
> with NULL pointer. Restore the old behaviour.
> 
> Fixes: 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in kobject_cleanup()")
> Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>

Sorry, I should use my suse mailbox for that.

> Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Reviewed-by: Qu Wenruo <wqu@suse.com>

Thanks,
Qu

> ---
> v2: replaced ?: with plain conditional (Greg)
>  lib/kobject.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/kobject.c b/lib/kobject.c
> index 3afb939f2a1c..9dce68c378e6 100644
> --- a/lib/kobject.c
> +++ b/lib/kobject.c
> @@ -637,8 +637,12 @@ static void __kobject_del(struct kobject *kobj)
>   */
>  void kobject_del(struct kobject *kobj)
>  {
> -	struct kobject *parent = kobj->parent;
> +	struct kobject *parent;
> +
> +	if (!kobj)
> +		return;
>  
> +	parent = kobj->parent;
>  	__kobject_del(kobj);
>  	kobject_put(parent);
>  }
> 

Re: [PATCH v2] kobject: Restore old behaviour of kobject_del(NULL)

[Greg Kroah-Hartman]

On Mon, Aug 03, 2020 at 11:27:06AM +0300, Andy Shevchenko wrote:
> The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in
> kobject_cleanup()") inadvertently dropped a possibility to call kobject_del()
> with NULL pointer. Restore the old behaviour.
> 
> Fixes: 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in kobject_cleanup()")
> Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
> Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> v2: replaced ?: with plain conditional (Greg)
>  lib/kobject.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)

Thanks, much better, will queue up after -rc1 is out.

greg k-h

Re: [PATCH v2] kobject: Restore old behaviour of kobject_del(NULL)

[Andy Shevchenko]

On Mon, Aug 03, 2020 at 11:46:59AM +0200, Greg Kroah-Hartman wrote:
> On Mon, Aug 03, 2020 at 11:27:06AM +0300, Andy Shevchenko wrote:
> > The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in
> > kobject_cleanup()") inadvertently dropped a possibility to call kobject_del()
> > with NULL pointer. Restore the old behaviour.
> > 
> > Fixes: 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in kobject_cleanup()")
> > Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
> > Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > ---
> > v2: replaced ?: with plain conditional (Greg)
> >  lib/kobject.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> Thanks, much better, will queue up after -rc1 is out.

Shouldn't be this taken care of?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2] kobject: Restore old behaviour of kobject_del(NULL)

[Greg Kroah-Hartman]

On Tue, Aug 25, 2020 at 05:41:09PM +0300, Andy Shevchenko wrote:
> On Mon, Aug 03, 2020 at 11:46:59AM +0200, Greg Kroah-Hartman wrote:
> > On Mon, Aug 03, 2020 at 11:27:06AM +0300, Andy Shevchenko wrote:
> > > The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in
> > > kobject_cleanup()") inadvertently dropped a possibility to call kobject_del()
> > > with NULL pointer. Restore the old behaviour.
> > > 
> > > Fixes: 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in kobject_cleanup()")
> > > Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
> > > Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > > ---
> > > v2: replaced ?: with plain conditional (Greg)
> > >  lib/kobject.c | 6 +++++-
> > >  1 file changed, 5 insertions(+), 1 deletion(-)
> > 
> > Thanks, much better, will queue up after -rc1 is out.
> 
> Shouldn't be this taken care of?

Yes, will get to it soon, after -rc1 is tough, combined with Plumbers...

greg k-h