linux-kernel - Re: [PATCH 0/7] rtc: Add support for limited alarm timer offsets

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:   Wed, 16 Aug 2023 18:14:35 +0200
From:   Alexandre Belloni <alexandre.belloni@...tlin.com>
To:     Guenter Roeck <linux@...ck-us.net>
Cc:     Alessandro Zummo <a.zummo@...ertech.it>,
        Benson Leung <bleung@...omium.org>,
        Miquel Raynal <miquel.raynal@...tlin.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        John Stultz <jstultz@...gle.com>,
        Stephen Boyd <sboyd@...nel.org>, linux-rtc@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Brian Norris <briannorris@...omium.org>
Subject: Re: [PATCH 0/7] rtc: Add support for limited alarm timer offsets

On 16/08/2023 08:50:12-0700, Guenter Roeck wrote:
> > I'm fine with the series, however, this doesn't solve the issue for RTCs
> > that have an absolute limit on the alarm (as opposed to an offset to the
> > current time/date).
> > 
> 
> I thought that is checked by rtc_valid_range() in rtc_set_alarm().
> Am I missing something ? Of course that assumes that the absolute
> maximum alarm timeout matches range_max, but I didn't find any
> drivers where that would not be the case.
> 

There are RTCs where this is not the case. When this is far away in the
future enough, the usual solution is to clip range_max which works but
is not really great intellectually.

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com