drm/virtio: fix NULL pointer dereference in virtiogpuconngetmodes
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.18.3 by commit 0f8bc147a963686b7351aa35d1701124ffacac08. For more details please see the references link.