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Message-ID: <d4779143-bb91-4d8e-a336-eeefc3131c05@mev.co.uk>
Date: Wed, 17 Jan 2024 13:52:32 +0000
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Subject: Re: [PATCH] comedi: drivers: ni_tio: Fix arithmetic expression
 overflow
To: Denis Arefev <arefev@swemel.ru>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>,
 open list <linux-kernel@vger.kernel.org>, lvc-project@linuxtesting.org
References: <20240117124229.37455-1-arefev@swemel.ru>
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From: Ian Abbott <abbotti@mev.co.uk>
Organization: MEV Ltd.
In-Reply-To: <20240117124229.37455-1-arefev@swemel.ru>
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On 17/01/2024 12:42, Denis Arefev wrote:
> The value of an arithmetic expression period_ns * 1000 is subject
> to overflow due to a failure to cast operands to a larger data
> type before performing arithmetic
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Denis Arefev <arefev@swemel.ru>
> ---
>   drivers/comedi/drivers/ni_tio.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/comedi/drivers/ni_tio.c b/drivers/comedi/drivers/ni_tio.c
> index da6826d77e60..acc914903c70 100644
> --- a/drivers/comedi/drivers/ni_tio.c
> +++ b/drivers/comedi/drivers/ni_tio.c
> @@ -800,7 +800,7 @@ static int ni_tio_set_clock_src(struct ni_gpct *counter,
>   				GI_PRESCALE_X2(counter_dev->variant) |
>   				GI_PRESCALE_X8(counter_dev->variant), bits);
>   	}
> -	counter->clock_period_ps = period_ns * 1000;
> +	counter->clock_period_ps = period_ns * 1000UL;
>   	ni_tio_set_sync_mode(counter);
>   	return 0;
>   }

Looks good, thanks!

Reviewed-by: Ian Abbott <abbotti@mev.co.uk>

Could you resend it and Cc Greg Kroah-Hartman 
<gregkh@linuxfoundation.org> ?  It's more likely to get applied that way 
because I don't maintain my own kernel tree for comedi.  Feel free to 
add my Reviewed-by line.

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