linux-kernel - RE: [PATCH 000/100] rtc: remove cargo culted code

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]

Message-ID: <6ED8E3B22081A4459DAC7699F3695FB70194158130@SW-EX-MBX01.diasemi.com>
Date:   Fri, 2 Mar 2018 09:06:28 +0000
From:   Steve Twiss <stwiss.opensource@...semi.com>
To:     Alexandre Belloni <alexandre.belloni@...tlin.com>
CC:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-rtc@...r.kernel.org" <linux-rtc@...r.kernel.org>
Subject: RE: [PATCH 000/100] rtc: remove cargo culted code

On 02 March 2018 08:57, Alexandre Belloni wrote:

> To: Steve Twiss
> Cc: linux-kernel@...r.kernel.org; linux-rtc@...r.kernel.org
> Subject: Re: [PATCH 000/100] rtc: remove cargo culted code
> 
> On 02/03/2018 at 08:46:48 +0000, Steve Twiss wrote:
> > Hi Alexandre,
> >
> > Acked for:
> >   rtc: da9063: stop validating rtc_time in .read_time
> >   rtc: da9052: stop validating rtc_time in .read_time
> >   rtc: da9055: stop validating rtc_time in .read_time
> >
> > Acked-by: Steve Twiss <stwiss.opensource@...semi.com>
> >

[...]

> > But after some further looking, I have not got any explicit case of how the
> > time read directly from the DA9063
> > registers can be incorrectly represented. So there should be no need to
> > check this.
> 
> My point is that it is checked later in the core anyway so you end up
> doing:
> 
> da9063_rtc_read_time()
> 	return rtc_valid_tm(tm);
> 
> __rtc_read_time()
> 	if (err < 0)
> 		return err;
> 	err = rtc_valid_tm(tm);
> 
> 	return err;
> 
> So the check in da9063_rtc_read_time is always pointless.

Ahh. I see. Thanks!
Regards,
Steve