Super cool. Also, love reading high quality linux patches. I think many, myself previously included, are afraid to even read the kernel source as one thinks it must be super complex. Of course some parts really are. However, the code is honestly of such high quality. I also highly value that feeling of realizing something once thought 'arcane' was actually only made by other humans, and it is legal to go read it and learn from it.
Clever! I know some will say it's like closing the barn door after the horse left, but having this in place to mitigate future vulnerabilities will be handy.
this sounds simple, but not running a function doesn't on its own mean safe behavior, if the caller code wasn't written keeping in mind this novel potential refusal as an outcome
IIRC canonical makes patches for official ubuntu kernels but acts like a Chinese restaurant (closed kitchen, orders come in through a small hatch behind the counter)
