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Date:   Fri, 3 Nov 2023 06:53:29 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Philipp Stanner <pstanner@redhat.com>
Cc:     Ian Abbott <abbotti@mev.co.uk>,
        H Hartley Sweeten <hsweeten@visionengravers.com>,
        Ivan Orlov <ivan.orlov0322@gmail.com>,
        Benjamin Tissoires <benjamin.tissoires@redhat.com>,
        linux-kernel@vger.kernel.org, Dave Airlie <airlied@redhat.com>
Subject: Re: [PATCH] drivers/comedi: copy userspace array safely
Message-ID: <2023110348-drained-tameness-b943@gregkh>
References: <20231102190848.51376-2-pstanner@redhat.com>
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On Thu, Nov 02, 2023 at 08:08:49PM +0100, Philipp Stanner wrote:
> comedi_fops.c utilizes memdup_user() to copy a userspace array. This
> does not check for an overflow.

Is there potential for an overflow today?

> 
> Use the new wrapper memdup_array_user() to copy the array more safely.

How about saying something like:
	"Use the new function memdup_array_user() in case things change
	in the future which would prevent overflows if something were to
	change in the size of the structures".

Or something to the affect of "all is good today, but make it easy to be
correct in the future as well".

thanks,

greg k-h