Re: [PATCH bpf-next v2 0/3] BPF signature hash chains

[Alexei Starovoitov <alexei.starovoitov@gmail.com>]

On Thu, Oct 16, 2025 at 6:36 PM Paul Moore <paul@paul-moore.com> wrote:
>
> On Thu, Oct 16, 2025 at 6:01 PM Alexei Starovoitov
> <alexei.starovoitov@gmail.com> wrote:
> > On Thu, Oct 16, 2025 at 1:51 PM Paul Moore <paul@paul-moore.com> wrote:
> > > On Sun, Oct 12, 2025 at 10:12 PM Paul Moore <paul@paul-moore.com> wrote:
> > > > On Sat, Oct 11, 2025 at 1:09 PM James Bottomley
> > > > <James.Bottomley@hansenpartnership.com> wrote:
> > > > > On Sat, 2025-10-11 at 09:31 -0700, Alexei Starovoitov wrote:
> > > > > > On Sat, Oct 11, 2025 at 7:52 AM James Bottomley
> > > > > > <James.Bottomley@hansenpartnership.com> wrote:
> > > > > > >
> > > > > > > It doesn't need to, once we check both the loader and the map, the
> > > > > > > integrity is verified and the loader can be trusted to run and
> > > > > > > relocate the map into the bpf program
> > > > > >
> > > > > > You should read KP's cover letter again and then research trusted
> > > > > > hash chains. Here is a quote from the first googled link:
> > > > > >
> > > > > > "A trusted hash chain is a cryptographic process used to verify the
> > > > > > integrity and authenticity of data by creating a sequence of hash
> > > > > > values, where each hash is linked to the next".
> > > > > >
> > > > > > In addition KP's algorithm was vetted by various security teams.
> > > > > > There is nothing novel here. It's a classic algorithm used
> > > > > > to verify integrity and that's what was implemented.
> > > > >
> > > > > Both KP and Blaise's patch sets are implementations of trusted hash
> > > > > chains.  The security argument isn't about whether the hash chain
> > > > > algorithm works, it's about where, in relation to the LSM hook, the
> > > > > hash chain verification completes.
> >
> > Not true. Blaise's patch is a trusted hash chain denial.
>
> It would be helpful if you could clarify what you mean by "trusted
> hash chain denial" and how that differs from a "trusted hash chain".

Paul,
This is getting ridiculous. You're arguing about the code that you
don't understand. Stop this broken phone and let Blaise defend his code.