[PATCH] drm/rockchip: check yuv2yuv existence before assigning window data

[Heiko Stuebner]

Before assigning window data, we should check if the yuv2yuv vop-data
is set at all, because it looks like it can otherwise reference something
wrong, as I saw on my rk3188 today which ended up in a null pointer
dereference in vop_plane_atomic_update when accessing the yuv2yuv data.

Fixes: 1c21aa8f2b68 ("drm/rockchip: Fix YUV buffers color rendering")
Signed-off-by: Heiko Stuebner <heiko at sntech.de>
---
 drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index 619b6db05d58..1dc9fd1ffbe3 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -1675,7 +1675,9 @@ static void vop_win_init(struct vop *vop)
 
 		vop_win->data = win_data;
 		vop_win->vop = vop;
-		vop_win->yuv2yuv_data = &vop_data->win_yuv2yuv[i];
+
+		if (vop_data->win_yuv2yuv)
+			vop_win->yuv2yuv_data = &vop_data->win_yuv2yuv[i];
 	}
 }
 
-- 
2.19.2