linux-kernel - Re: [PATCH] pinctrl: intel: fix NULL pointer deref

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 10 Jun 2021 17:32:46 +0300
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Henning Schild <henning.schild@...mens.com>
Cc:     Mika Westerberg <mika.westerberg@...ux.intel.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@...r.kernel.org>,
        Andy Shevchenko <andy@...nel.org>,
        Linus Walleij <linus.walleij@...aro.org>
Subject: Re: [PATCH] pinctrl: intel: fix NULL pointer deref

On Thu, Jun 10, 2021 at 05:25:04PM +0300, Andy Shevchenko wrote:
> On Wed, Jun 09, 2021 at 01:08:16PM +0200, Henning Schild wrote:
> > Am Wed, 9 Jun 2021 13:33:34 +0300
> > schrieb Andy Shevchenko <andy.shevchenko@...il.com>:
> 
> ...
> 
> > In order to use GPIO from the drivers i need to make sure
> > "broxton-pinctrl" comes up even if p2sb is hidden.
> > 
> > Long story short, i thought the patch was simple enough to merge even
> > taken out of my special context.
> > 
> > Currently intel_pinctl only works if "ps2b is not hidden by BIOS" or
> > "ACPI tables are correct", lifting the ban on the hidden p2sb seems
> > like a useful thing in general (i.e. sysfs gpio interface). And i was
> > hoping Andy would take the lead on that. It is something my Siemens
> > drivers would depend on, but really a generic thing as far as i
> > understand it.
> 
> From p2sb series discussion it appears that this patch is not needed.
> The case is when BIOS already provides an ACPI device.
> 
> So, the initial bug is in that series that needs to check if the ACPI device is
> exposed and forbid platform device instantiation in that case.

Actually, I'm still thinking how this ever possible. We have all drivers to
provide SoC data pointers. match data may be NULL if and only if the ACPI
device provided is a new one that doesn't provide a SoC data.

So, w/o seeing ACPI table, I'm really puzzled here.

-- 
With Best Regards,
Andy Shevchenko