Virtualization - Jul 2021 - [PATCH AUTOSEL 4.9 09/35] drm/virtio: Fix double free on probe failure

From: Xie Yongji <xieyongji at bytedance.com>

[ 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 at bytedance.com>
Link:
http://patchwork.freedesktop.org/patch/msgid/20210517084913.403-2-xieyongji at
bytedance.com
Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/virtio/virtgpu_kms.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c
b/drivers/gpu/drm/virtio/virtgpu_kms.c
index d8b2027730d0..cde38e14232c 100644
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -234,6 +234,7 @@ int virtio_gpu_driver_load(struct drm_device *dev, unsigned
long flags)
 err_vbufs:
 	vgdev->vdev->config->del_vqs(vgdev->vdev);
 err_vqs:
+	dev->dev_private = NULL;
 	kfree(vgdev);
 	return ret;
 }
-- 
2.30.2