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Date:   Wed, 16 Jan 2019 12:28:00 +0100
From:   Gerd Hoffmann <kraxel@redhat.com>
To:     Frediano Ziglio <fziglio@redhat.com>
Cc:     dri-devel@lists.freedesktop.org, David Airlie <airlied@linux.ie>,
        open list <linux-kernel@vger.kernel.org>,
        "open list:DRM DRIVER FOR QXL VIRTUAL GPU" 
        <virtualization@lists.linux-foundation.org>,
        Daniel Vetter <daniel@ffwll.ch>,
        "open list:DRM DRIVER FOR QXL VIRTUAL GPU" 
        <spice-devel@lists.freedesktop.org>,
        Dave Airlie <airlied@redhat.com>
Subject: Re: [Spice-devel] [PATCH 1/3] drm/qxl: add mode/framebuffer check
 functions
Message-ID: <20190116112800.v73xmxedt4b3gktj@sirius.home.kraxel.org>
References: <20190116083521.22673-1-kraxel@redhat.com>
 <20190116083521.22673-2-kraxel@redhat.com>
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> > +static int qxl_check_mode(struct qxl_device *qdev,
> > +			  unsigned int width,
> > +			  unsigned int height)
> > +{
> > +	if (width * height * 4 > qdev->vram_size)
> 
> Is someone checking for integer overflows already?

Need to have a look.  This is just ...

> > -	if (bo->surf.stride * bo->surf.height > qdev->vram_size) {
> > -		DRM_ERROR("Mode doesn't fit in vram size (vgamem)");
> > -		return -EINVAL;
> > -	}

... that check moved into the new function.

cheers,
  Gerd