linux-kernel - Re: [PATCH] i2c: core: fix NULL pointer dereference in suspend/resume callbacks

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 for Android: free password hash cracker in your pocket

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

Date:   Fri, 22 May 2020 13:15:12 +0200
From:   Marek Szyprowski <m.szyprowski@...sung.com>
To:     linux-pm@...r.kernel.org, linux-i2c@...r.kernel.org,
        linux-kernel@...r.kernel.org
Cc:     Wolfram Sang <wsa@...-dreams.de>,
        Bibby Hsieh <bibby.hsieh@...iatek.com>,
        Tomasz Figa <tfiga@...omium.org>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>,
        srv_heupstream@...iatek.com,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
        linux-samsung-soc@...r.kernel.org
Subject: Re: [PATCH] i2c: core: fix NULL pointer dereference in
 suspend/resume callbacks

Hi All,

On 22.05.2020 12:13, Marek Szyprowski wrote:
> Commit 6fe12cdbcfe3 ("i2c: core: support bus regulator controlling in
> adapter") added generic suspend and resume functions for i2c devices.
> Those functions unconditionally access an i2c_client structure assigned
> to the given i2c device. However, there exist i2c devices in the system
> without a valid i2c_client. Add the needed check before accessing the
> i2c_client.

Just one more comment. The devices without i2c_client structure are the 
i2c 'devices' associated with the respective i2c bus. They are visible 
in /sys:

ls -l /sys/bus/i2c/devices/i2c-*

I wonder if this patch has been ever tested with system suspend/resume, 
as those devices are always available in the system...

> ...

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland