Re: [Qemu-devel] [PATCH 3/5] vmware-vga: use vmsvga_verify_rect in vmsvga_update_rect

[BALATON Zoltan]

On Tue, 14 Oct 2014, Gerd Hoffmann wrote:
> Switch vmsvga_update_rect over to use vmsvga_verify_rect.  Slight change
> in behavior:  We don't try to automatically fixup rectangles any more.
> Invalid update requests will be ignored instead.

Are you sure this won't break clients? I remember that maybe Windows 
drivers did produce requests with partially off screen rectangles for 
objects that are partially visible. I don't recall if this was for windows 
dragged off screen or mouse pointer near the screen but there was a reason 
this fixup was added. Did you test this?

Regards,
BALATON Zoltan

> Cc: address@hidden
> Signed-off-by: Gerd Hoffmann <address@hidden>
> ---
> hw/display/vmware_vga.c | 32 ++------------------------------
> 1 file changed, 2 insertions(+), 30 deletions(-)
>
> diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c
> index fc0a2a7..7564f88 100644
> --- a/hw/display/vmware_vga.c
> +++ b/hw/display/vmware_vga.c
> @@ -356,36 +356,8 @@ static inline void vmsvga_update_rect(struct 
> vmsvga_state_s *s,
>     uint8_t *src;
>     uint8_t *dst;
>
> -    if (x < 0) {
> -        fprintf(stderr, "%s: update x was < 0 (%d)\n", __func__, x);
> -        w += x;
> -        x = 0;
> -    }
> -    if (w < 0) {
> -        fprintf(stderr, "%s: update w was < 0 (%d)\n", __func__, w);
> -        w = 0;
> -    }
> -    if (x + w > surface_width(surface)) {
> -        fprintf(stderr, "%s: update width too large x: %d, w: %d\n",
> -                __func__, x, w);
> -        x = MIN(x, surface_width(surface));
> -        w = surface_width(surface) - x;
> -    }
> -
> -    if (y < 0) {
> -        fprintf(stderr, "%s: update y was < 0 (%d)\n",  __func__, y);
> -        h += y;
> -        y = 0;
> -    }
> -    if (h < 0) {
> -        fprintf(stderr, "%s: update h was < 0 (%d)\n",  __func__, h);
> -        h = 0;
> -    }
> -    if (y + h > surface_height(surface)) {
> -        fprintf(stderr, "%s: update height too large y: %d, h: %d\n",
> -                __func__, y, h);
> -        y = MIN(y, surface_height(surface));
> -        h = surface_height(surface) - y;
> +    if (!vmsvga_verify_rect(surface, __func__, x, y, w, h)) {
> +        return;
>     }
>
>     bypl = surface_stride(surface);
> --
> 1.8.3.1