[PATCH v3 0/4] Introducing Hornet LSM

[Paul Moore]

On Wed, May 7, 2025 at 1:48 PM James Bottomley
<James.Bottomley at hansenpartnership.com> wrote:
>
> I'm with Paul on this: if you could share your design ideas more fully
> than you have above that would help make this debate way more
> technical.

I think it would also help some of us, at the very least me, put your
objections into context.  I believe the more durable solutions that
end up in Linus' tree are combinations of designs created out of
compromise, and right now we are missing the context and detail of
your ideal solution to be able to do that compromise and get to a
design and implementation we can all begrudgingly accept.  In the
absence of a detailed alternate design, and considering that BPF
signature validation efforts have sputtered along for years without
any real success, we'll continue to push forward on-list with
refinements to the current proposal in an effort to drive this to some
form of resolution.

> I also get the impression that there might be a disagreement over
> scope: what seems to be coming out of BPF is that every signing problem
> and scenario must be solved before signing can be considered
> acceptable; however, I think it's not unreasonable to attempt to cover
> a portion of the use cases and allow for future additions of things
> like policy so we can get some forward motion to allow others to play
> with it and produce patches based on their use cases.

Beyond any potential future updates to Hornet, I just wanted to make
it clear that the Hornet LSM approach, like any LSM, can be disabled
both at compile time for those users who build their own kernels, as
well as at kernel boot time using the "lsm=" command line option for
those who are limited to pre-built kernels, e.g. distro kernels.
Users can always disable Hornet and replace it with another LSM,
either a BPF LSM or a native/C LSM, of their choosing; the LSM
framework is intentionally flexible to allow for this substitution and
replacement, with plenty of existing examples already.

-- 
paul-moore.com