linux-kernel - Re: [PATCH 1/2] watchdog: cadence_wdt: Enable access to module parameters

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]

Message-ID: <54da75b5-aff9-84e8-1e3e-f311b358f77a@monstr.eu>
Date:   Fri, 4 Aug 2017 15:52:46 +0200
From:   Michal Simek <monstr@...str.eu>
To:     Guenter Roeck <linux@...ck-us.net>,
        Michal Simek <michal.simek@...inx.com>,
        linux-kernel@...r.kernel.org
Cc:     linux-watchdog@...r.kernel.org, Wim Van Sebroeck <wim@...ana.be>
Subject: Re: [PATCH 1/2] watchdog: cadence_wdt: Enable access to module
 parameters

On 4.8.2017 15:45, Guenter Roeck wrote:
> On 08/04/2017 12:39 AM, Michal Simek wrote:
>> Give read access to module parameters to all and write access to root.
>> This change also improves driver error path testing.
>>
>> Signed-off-by: Michal Simek <michal.simek@...inx.com>
>> ---
>>
>> Please let me know what you think - I can use macros from stat.h if
>> required
>>
> 
> Seems to be quite pointless and misleading, since the values are only read
> at probe time. Am I missing something ?

You can unbind device and bind that device again. If you want to use it
or test with different parameters you need to have an access to these
module parameters.
For testing purpose if you setup for example timeout to 1000s which is
more than CDNS_WDT_MAX_TIMEOUT probe will fail and you have better
driver coverage.

I see that a lot of watchdog drivers are using 0 there - means no sysfs
access to these modules parameters. Some of them are using 0644 or 0444
that's why I want to know if there is any for example security reason to
disable access to these parameters.

Thanks,
Michal

-- 
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Xilinx Microblaze
Maintainer of Linux kernel - Xilinx Zynq ARM and ZynqMP ARM64 SoCs
U-Boot custodian - Xilinx Microblaze/Zynq/ZynqMP SoCs

Download attachment "signature.asc" of type "application/pgp-signature" (199 bytes)