linux-kernel - Re: [PATCH] rtc-ds1302: handle write protection

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] [day] [month] [year] [list]

Date:	Fri, 31 May 2013 14:48:46 +0200
From:	Marc Zyngier <maz@...terjones.org>
To:	Sergey Yanovich <ynvich@...il.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	<rtc-linux@...glegroups.com>, <linux-kernel@...r.kernel.org>,
	Alessandro Zummo <a.zummo@...ertech.it>,
	Sachin Kamat <sachin.kamat@...aro.org>,
	Jingoo Han <jg1.han@...sung.com>
Subject: Re: [PATCH] rtc-ds1302: handle write protection

On Thu, 30 May 2013 20:04:48 +0400, Sergey Yanovich <ynvich@...il.com>
wrote:
> From f1cd048a066b249082752a96abce7d33a0cd4ea3 Mon Sep 17 00:00:00 2001
> From: Sergey Yanovich <ynvich@...il.com>
> Date: Tue, 21 May 2013 03:06:31 +0400
> Subject: [PATCH] rtc-ds1302: handle write protection
> 
> This chip has a control register and can prevent altering saved clock.
> Without this patch we could have:
> ----8<----
> (arm)root@...14:~# date
> Tue May 21 03:08:27 MSK 2013
> (arm)root@...14:~# /etc/init.d/hwclock.sh show
> Tue May 21 11:13:58 2013  -0.067322 seconds
> (arm)root@...14:~# /etc/init.d/hwclock.sh stop
> [info] Saving the system clock.
> [info] Hardware Clock updated to Tue May 21 03:09:01 MSK 2013.
> (arm)root@...14:~# /etc/init.d/hwclock.sh show
> Tue May 21 11:14:15 2013  -0.624272 seconds
> ----8<----
> 
> The patch enables write access to rtc before the driver tries to write
time
> and re-disables when time data is written.
> 
> Signed-off-by: Sergey Yanovich <ynvich@...il.com>

FWIW,

Acked-by: Marc Zyngier <maz@...terjones.org>

        M.
-- 
Who you jivin' with that Cosmik Debris?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/