Linux kernel (drivers/gpu/drm/xe): The GPU VM is published into the id table before the create ioctl finishes with it

Impact

The GPU VM is published into the id table before the create ioctl finishes with it, so a tenant that guesses the id and calls VM destroy in parallel frees the VM while the create path is still using it. Use-after-free of a driver object under attacker timing control - the standard route from a tenant container to kernel code execution. The upstream fix names the attacker explicitly.

Who can reach it

Hostile tenant holding /dev/dri/renderD* on Intel xe: one thread spams VM_CREATE, another spams VM_DESTROY against the predictable next id. Unprivileged, no display access, no special platform features.

What to do

Update to a kernel carrying the fix (stable commits below; no fixed_in published). Interim: remove /dev/dri/renderD* from containers running untrusted code on xe nodes - the ioctl pair cannot be filtered selectively.

References