[Spice-devel] [PATCH v2] red-parse-qxl: Check consistency of QXL_DRAW_COPY operations

[Frediano Ziglio]

> 
> > 
> > The source area should not extend outside the source bitmap, or have
> > swapped coordinates.
> > 
> > Signed-off-by: Francois Gouget <fgouget at codeweavers.com>
> > ---
> >  server/red-parse-qxl.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> 
> I checked and if this function return error the resource is correctly
> released.
> 
> > diff --git a/server/red-parse-qxl.c b/server/red-parse-qxl.c
> > index 0dafbef..d1f0ea7 100644
> > --- a/server/red-parse-qxl.c
> > +++ b/server/red-parse-qxl.c
> > @@ -682,6 +682,18 @@ static int red_get_copy_ptr(RedMemSlotInfo *slots, int
> > group_id,
> >          return 1;
> >      }
> >      red_get_rect_ptr(&red->src_area, &qxl->src_area);
> > +    /* The source area should not extend outside the source bitmap or have
> > +     * swapped coordinates.
> > +     */
> > +    if (red->src_bitmap->descriptor.type == SPICE_IMAGE_TYPE_BITMAP &&
> 
> Why this check? I think should be valid for any kind of image, even
> jpeg, lz or whatever.
> Maybe would be worth to have a function to check any rect so
> could be reused.
> 

Sorry, the check is for the red->src_bitmap->u.bitmap access.

> > +        (red->src_area.left < 0 ||
> > +         red->src_area.left > red->src_area.right ||
> > +         red->src_area.right > red->src_bitmap->u.bitmap.x ||
> > +         red->src_area.top < 0 || red->src_area.top > red->src_area.bottom
> > ||
> > +         red->src_area.bottom > red->src_bitmap->u.bitmap.y)) {
> > +        red_put_image(red->src_bitmap);
> 
> Mm... this make me think you didn't test the code.. this cause
> a double free in the current code
> 
> > +        return 1;
> > +    }
> >      red->rop_descriptor  = qxl->rop_descriptor;
> >      red->scale_mode      = qxl->scale_mode;
> >      red_get_qmask_ptr(slots, group_id, &red->mask, &qxl->mask, flags);
> 

Frediano