Re: [PATCH 007/190] Revert "media: ti-vpe: Fix a missing check and reference count leak"

Greg Kroah-Hartman
2021-04-27T13:11:12Z

On Thu, Apr 22, 2021 at 10:10:50AM +0200, Hans Verkuil wrote:
> On 21/04/2021 14:58, Greg Kroah-Hartman wrote:
> > This reverts commit 7dae2aaaf432767ca7aa11fa84643a7c2600dbdd.
> >
> > Commits from @umn.edu addresses have been found to be submitted in "bad
> > faith" to try to test the kernel community's ability to review "known
> > malicious" changes. The result of these submissions can be found in a
> > paper published at the 42nd IEEE Symposium on Security and Privacy
> > entitled, "Open Source Insecurity: Stealthily Introducing
> > Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University
> > of Minnesota) and Kangjie Lu (University of Minnesota).
> >
> > Because of this, all submissions from this group must be reverted from
> > the kernel tree and will need to be re-reviewed again to determine if
> > they actually are a valid fix. Until that work is complete, remove this
> > change to ensure that no problems are being introduced into the
> > codebase.
> >
> > Cc: Qiushi Wu <wu000273@umn.edu>
> > Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
> > Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > ---
> > drivers/media/platform/ti-vpe/vpe.c | 2 --
> > 1 file changed, 2 deletions(-)
> >
> > diff --git a/drivers/media/platform/ti-vpe/vpe.c b/drivers/media/platform/ti-vpe/vpe.c
> > index 10251b787674..c7a0a7c19ca6 100644
> > --- a/drivers/media/platform/ti-vpe/vpe.c
> > +++ b/drivers/media/platform/ti-vpe/vpe.c
> > @@ -2473,8 +2473,6 @@ static int vpe_runtime_get(struct platform_device *pdev)
> >
> > r = pm_runtime_get_sync(&pdev->dev);
> > WARN_ON(r < 0);
> > - if (r)
>
> This should have been: if (r < 0)
>
> I missed that as a reviewer, and I don't think it was intentional either
> since I couldn't find any clear documentation in pm_runtime_get_sync()
> that it can return 0 or 1 as success. After going through a few wrapper
> functions you end up in rpm_resume() in drivers/base/power/runtime.c
> which doesn't document the return code.
>
> So keep this reverted and I'll make a new patch for this later.
>
> I've CC-ed Rafael and Pavel: it would be really nice if someone can
> document the return code from rpm_resume() in drivers/base/power/runtime.c.
>
> I just discovered that it is documented in Documentation/power/runtime_pm.rst,
> but if you just look at the code then you'll miss this.

Mauro asked for me to drop this one, as he's fixing them all up in a
"better" way with a follow-on patch series.

thanks,

greg k-h