This "untrusted data" patch series from Benno Lossin is the result of conversations at last weekend's Rust Linux kernel conference in Copenhagen:

https://lore.kernel.org/all/20240913112643.542914-1-benno.lossin@proton.me/

It's not a "silver bullet" for why we should be using rust in the Linux kernel, but it is a "big giant sledgehammer" to help squash and prevent from happening MANY common types of kernel vulnerabilities and bugs (remember, "all input is evil!" and this change forces you to always be aware of that, which is something that C in the kernel does not.)

I had always felt that Rust was the future for what we need to do in Linux, but now I'm sure, because if we can do stuff like this, with no overhead involved (it's all checked at build time), then we would be foolish not to give it a real try.

And yes, I've asked for this for years from the C developers, and maybe we can also do it there, but it's not obvious how and no one has come up with a way to do so. Maybe now they will have some more incentive :)

Here is a hopefully-useful notice about Linux kernel security issues, as it seems like this knowledge isn't distributed very widely based on the number of emails I get on a weekly basis:

- The kernel security team does not have any "early notice"
announcement list for security fixes for anyone, as that would only
make things more insecure for everyone.

- The kernel community does not assign CVEs, nor do we deal with them
at all. This is documented in the kernel's security policy, yet we
still have a number of people asking for CVE numbers even after
reading that policy. See my longer "CVEs are dead..." talk for full
details about how the CVE process is broken for projects like Linux:
https://kernel-recipes.org/en/2019/talks/cves-are-dead-long-live-the-cve/

- You HAVE to take all of the stable/LTS releases in order to have a
secure and stable system. If you attempt to cherry-pick random
patches you will NOT fix all of the known, and unknown, problems,
but rather you will end up with a potentially more insecure system,
and one that contains known bugs. Reliance on an "enterprise"
distribution to provide this for your systems is up to you, discuss
it with them as to how they achieve this result as this is what you
are paying for. If you aren't paying for it, just use Debian, they
know what they are doing and track the stable kernels and have a
larger installed base than any other Linux distro. For embedded,
use Yocto, they track the stable releases, or keep your own
buildroot-based system up to date with the new releases.

- Test all stable/LTS releases on your workload and hardware before
putting the kernel into "production" as everyone runs a different %
of the kernel source code from everyone else (servers run about
1.5mil lines of code, embedded runs about 3.5mil lines of code, your
mileage will vary). If you can't test releases before moving them
into production, you might want to solve that problem first.

- A fix for a known bug is better than the potential of a fix causing a
future problem as future problems, when found, will be fixed then.

I think I need to give another talk about this issue to go into the above in more detail. So much for me giving a technical talk at Kernel Recipes this year...