Re: [PATCH v3,03/21] v4l2: verify secure dmabufs are used in secure queue

[Jeffrey Kardatzke]

On Mon, Dec 11, 2023 at 2:58 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>
> On 06/12/2023 09:15, Yunfei Dong wrote:
> > From: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx>
> >
> > Verfies in the dmabuf implementations that if the secure memory flag is
>
> Verfies -> Verifies

Thanks. Yunfei, change that please.
>
> > set for a queue that the dmabuf submitted to the queue is unmappable.
> >
> > Signed-off-by: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx>
> > Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx>
> > ---
> >  drivers/media/common/videobuf2/videobuf2-dma-contig.c | 6 ++++++
> >  drivers/media/common/videobuf2/videobuf2-dma-sg.c     | 6 ++++++
> >  2 files changed, 12 insertions(+)
> >
> > diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> > index 3d4fd4ef5310..ad58ef8dc231 100644
> > --- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> > +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> > @@ -710,6 +710,12 @@ static int vb2_dc_map_dmabuf(void *mem_priv)
> >               return -EINVAL;
> >       }
> >
> > +     /* verify the dmabuf is secure if we are in secure mode */
> > +     if (buf->vb->vb2_queue->secure_mem && sg_page(sgt->sgl)) {
>
> This needs a bit more explanation. I guess that for secure memory
> sg_page returns NULL?

How about if we change it to:

/* verify the dmabuf is secure if we are in secure mode, this is done
by validating there is no page entry for the dmabuf */

>
> > +             pr_err("secure queue requires secure dma_buf");
> > +             return -EINVAL;
> > +     }
> > +
> >       /* checking if dmabuf is big enough to store contiguous chunk */
> >       contig_size = vb2_dc_get_contiguous_size(sgt);
> >       if (contig_size < buf->size) {
> > diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> > index 28f3fdfe23a2..55428c73c380 100644
> > --- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> > +++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> > @@ -564,6 +564,12 @@ static int vb2_dma_sg_map_dmabuf(void *mem_priv)
> >               return -EINVAL;
> >       }
> >
> > +     /* verify the dmabuf is secure if we are in secure mode */
> > +     if (buf->vb->vb2_queue->secure_mem && !sg_dma_secure(sgt->sgl)) {
>
> I can't find the sg_dma_secure function. I suspect this patch series
> depends on another series?

That was an oversight, it should be the same as in
videobuf2-dma-contig.c. Yunfei, can you change this to match what's in
videobuf2-dma-contig.c after the comment is reworded?
>
> > +             pr_err("secure queue requires secure dma_buf");
> > +             return -EINVAL;
> > +     }
> > +
> >       buf->dma_sgt = sgt;
> >       buf->vaddr = NULL;
> >
>
> Regards,
>
>         Hans