Re: [PATCH] staging: rts5208: add check on NULL before dereference

[okaya]

On 2018-06-09 15:34, Andy Shevchenko wrote:
> On Sat, Jun 9, 2018 at 7:58 PM,  <okaya@xxxxxxxxxxxxxx> wrote:
> > On 2018-06-09 12:38, Anton Vasilyev wrote:
> > > If rtsx_probe fails to allocate dev->chip, then NULL pointer
> > > dereference occurs at rtsx_release_resources().
> > >
> > > Patch adds checks chip on NULL before its dereference at
> > > rtsx_release_resources and passing with dereference inside
> > > rtsx_release_chip.
> > >
> > > Found by Linux Driver Verification project (linuxtesting.org).
>
> > I think you should bail out if dev->chip is null rather than adding
> > conditiinals.
>
> I'm wondering if it's false positive. At which circumstances that may 
> happen?

Only if dev->chip allocation fails. Code tries to cleanup prior 
resources by calling clean_everything() function which ends up in 
rtsx_release_resources()