drm/virtio: Fix double free on probe failure

[ Upstream commit cec7f1774605a5ef47c134af62afe7c75c30b0ee ]

The virtio_gpu_init() will free vgdev and vgdev->vbufs on failure.
But such failure will be caught by virtio_gpu_probe() and then
virtio_gpu_release() will be called to do some cleanup which
will free vgdev and vgdev->vbufs again. So let's set dev->dev_private
to NULL to avoid double free.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210517084913.403-2-xieyongji@bytedance.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c
index eed57a9..a28b01f 100644 (file)
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -209,6 +209,7 @@ err_scanouts:
 err_vbufs:
        vgdev->vdev->config->del_vqs(vgdev->vdev);
 err_vqs:
+       dev->dev_private = NULL;
        kfree(vgdev);
        return ret;
 }