[PATCH AUTOSEL 5.4 15/74] drm/virtio: Fixes a potential NULL pointer dereference on probe failure

Sasha Levin
2021-07-06T12:20:16Z

From: Xie Yongji <xieyongji@bytedance.com>

[ Upstream commit 17f46f488a5d82c5568e6e786cd760bba1c2ee09 ]

The dev->dev_private might not be allocated if virtio_gpu_pci_quirk()
or virtio_gpu_init() failed. In this case, we should avoid the cleanup
in virtio_gpu_release().

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210517084913.403-1-xieyongji@bytedance.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/virtio/virtgpu_kms.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c
index 6dcc05ab31eb..5c0249d3bd53 100644
--- a/drivers/gpu/drm/virtio/virtgpu_kms.c
+++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
@@ -243,6 +243,9 @@ void virtio_gpu_deinit(struct drm_device *dev)
vgdev->vdev->config->reset(vgdev->vdev);
vgdev->vdev->config->del_vqs(vgdev->vdev);

+ if (!vgdev)
+ return;
+
virtio_gpu_modeset_fini(vgdev);
virtio_gpu_ttm_fini(vgdev);
virtio_gpu_free_vbufs(vgdev);
--
2.30.2