[OS-BUILD PATCH] drm/virtio: Fix NULL dereference error in virtio_gpu_poll
From: Vivek Kasireddy <vivek.kasireddy(a)intel.com>
drm/virtio: Fix NULL dereference error in virtio_gpu_poll
When virgl is not enabled, vfpriv pointer would not be allocated.
Therefore, check for a valid value before dereferencing.
Reported-by: Christian Zigotzky <chzigotzky(a)xenosoft.de>
Cc: Gurchetan Singh <gurchetansingh(a)chromium.org>
Cc: Gerd Hoffmann <kraxel(a)redhat.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy(a)intel.com>
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c
index blahblah..blahblah 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.c
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.c
@@ -163,10 +163,11 @@ static __poll_t virtio_gpu_poll(struct file *filp,
struct drm_file *drm_file = filp->private_data;
struct virtio_gpu_fpriv *vfpriv = drm_file->driver_priv;
struct drm_device *dev = drm_file->minor->dev;
+ struct virtio_gpu_device *vgdev = dev->dev_private;
struct drm_pending_event *e = NULL;
__poll_t mask = 0;
- if (!vfpriv->ring_idx_mask)
+ if (!vgdev->has_virgl_3d || !vfpriv || !vfpriv->ring_idx_mask)
return drm_poll(filp, wait);
poll_wait(filp, &drm_file->event_wait, wait);
--
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/1489