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Message-ID: <d14fddd9-20f9-fe7e-6c12-b5a57c6855da@linux.intel.com>
Date:   Thu, 19 May 2022 12:49:45 -0500
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Subject: Re: [PATCH] ASoC: max98090: Remove unneeded check in
 max98090_put_enab_tlv()
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To:     Mark Brown <broonie@kernel.org>,
        Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc:     ldv-project@linuxtesting.org, alsa-devel@alsa-project.org,
        Liam Girdwood <lgirdwood@gmail.com>,
        linux-kernel@vger.kernel.org, Takashi Iwai <tiwai@suse.com>
References: <1652980212-21473-1-git-send-email-khoroshilov@ispras.ru>
 <YoZ+dmprwb5Ohto3@sirena.org.uk>
From:   Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
In-Reply-To: <YoZ+dmprwb5Ohto3@sirena.org.uk>
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On 5/19/22 12:29, Mark Brown wrote:
> On Thu, May 19, 2022 at 08:10:12PM +0300, Alexey Khoroshilov wrote:
>> Variable sel is of unsigned int type, so sel < 0 is not required.
>>
>> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
>>  	val = (val >> mc->shift) & mask;
>>  
>> -	if (sel < 0 || sel > mc->max)
>> +	if (sel > mc->max)
> 
> The check needs to be moved, not removed.  The userspace ABI allows
> passing in of negative values.

I was about to send the same cleanup, cppcheck reports the same issue
with a useless test.

The problem is that the values coming from userspace are cast to unsigned...