The root cause of this vulnerability is that the ioctl$DRM_IOCTL_MODE_DESTROY_DUMB can decrease refcount of *drm_vgem_gem_object *(created in vgem_gem_dumb_create) concurrently, and *vgem_gem_dumb_create *will access the freed drm_vgem_gem_object.
[
{
"product": "kernel",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "kernel 5.x"
}
]
}
]