Re: [PATCH] media: vb2: add length check for mmap

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Friday 12 April 2013 08:03:15 Marek Szyprowski wrote:
> On 4/12/2013 5:57 AM, Seung-Woo Kim wrote:
> > The length of mmap() can be bigger than length of vb2 buffer, so
> > it should be checked.
> > 
> > Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
> 
> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>

This should be pushed to the stable kernels, as it's a potential security 
issue.

> > ---
> > 
> >   drivers/media/v4l2-core/videobuf2-core.c |    5 +++++
> >   1 files changed, 5 insertions(+), 0 deletions(-)
> > 
> > diff --git a/drivers/media/v4l2-core/videobuf2-core.c
> > b/drivers/media/v4l2-core/videobuf2-core.c index db1235d..2c6ff2d 100644
> > --- a/drivers/media/v4l2-core/videobuf2-core.c
> > +++ b/drivers/media/v4l2-core/videobuf2-core.c
> > @@ -1886,6 +1886,11 @@ int vb2_mmap(struct vb2_queue *q, struct
> > vm_area_struct *vma)> 
> >   	vb = q->bufs[buffer];
> > 
> > +	if (vb->v4l2_planes[plane].length < (vma->vm_end - vma->vm_start)) {
> > +		dprintk(1, "Invalid length\n");
> > +		return -EINVAL;
> > +	}
> > +
> > 
> >   	ret = call_memop(q, mmap, vb->planes[plane].mem_priv, vma);
> >   	if (ret)
> >   	
> >   		return ret;

-- 
Regards,

Laurent Pinchart