linux-kernel - Re: [PATCH 1/2] lib/string_helpers: Introduce strsplit

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: <e0c7d254-ace3-625c-cc83-52ca0b45e9fc@intel.com>
Date:   Fri, 8 Jul 2022 13:32:56 +0200
From:   Cezary Rojewski <cezary.rojewski@...el.com>
To:     Andy Shevchenko <andy.shevchenko@...il.com>
CC:     Andy Shevchenko <andy@...nel.org>, Mark Brown <broonie@...nel.org>,
        "ALSA Development Mailing List" <alsa-devel@...a-project.org>,
        Takashi Iwai <tiwai@...e.com>,
        Jaroslav Kysela <perex@...ex.cz>,
        <amadeuszx.slawinski@...ux.intel.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>,
        Hans de Goede <hdegoede@...hat.com>,
        Péter Ujfalusi <peter.ujfalusi@...ux.intel.com>,
        "Ranjani Sridharan" <ranjani.sridharan@...ux.intel.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        "Kai Vehmanen" <kai.vehmanen@...ux.intel.com>,
        Bard Liao <yung-chuan.liao@...ux.intel.com>
Subject: Re: [PATCH 1/2] lib/string_helpers: Introduce strsplit_u32()

On 2022-07-08 12:22 PM, Andy Shevchenko wrote:
> On Thu, Jul 7, 2022 at 11:03 AM Cezary Rojewski
> <cezary.rojewski@...el.com> wrote:
>>
>> Add strsplit_u32() and its __user variant to allow for splitting
>> specified string into array of u32 tokens.
> 
> And I believe we have more of this done in old code.
> Since all callers use ',' as a delimiter, have you considered using
> get_options()?

Thanks for your input, Andy.

When I'd written the very first version of this function many months 
ago, get_options() looked as it does not fulfill our needs. It seems to 
be true even today: caller needs to know the number of elements in an 
array upfront. Also, kstrtox() takes into account '0x' and modifies the 
base accordingly if that's the case. simple_strtoull() looks as not 
capable of doing the same thing.

The goal is to be able to parse input such as:

0x1000003,0,0,0x1000004,0,0

into a sequence of 6 uints, filling the *tkns and *num_tkns for the caller.

>> Originally this functionality was added for the SOF sound driver. As
>> more users are on the horizon, relocate it so it becomes a common good.
> 
> Maybe it can be fixed just there.

avs-driver, which is also part of the ASoC framework has very similar 
debug-interface. I believe there's no need to duplicate the functions - 
move them to common code instead.

Regards,
Czarek