[PATCH 5.19 067/717] drm/virtio: Check whether transferred 2D BO is shmem

Greg Kroah-Hartman
2022-10-22T08:37:44Z

From: Dmitry Osipenko <dmitry.osipenko@collabora.com>

commit e473216b42aa1fd9fc6b94b608b42c210c655908 upstream.

Transferred 2D BO always must be a shmem BO. Add check for that to prevent
NULL dereference if userspace passes a VRAM BO.

Cc: stable@vger.kernel.org
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220630200726.1884320-3-dmitry.osipenko@collabora.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/virtio/virtgpu_vq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -595,7 +595,7 @@ void virtio_gpu_cmd_transfer_to_host_2d(
bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);

- if (use_dma_api)
+ if (virtio_gpu_is_shmem(bo) && use_dma_api)
dma_sync_sgtable_for_device(vgdev->vdev->dev.parent,
shmem->pages, DMA_TO_DEVICE);