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Y. Srinivasan" , Daniel Borkmann , Andrii Nakryiko , wufan@linux.microsoft.com, Quentin Monnet Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Oct 16, 2025 at 6:36=E2=80=AFPM Paul Moore wr= ote: > > On Thu, Oct 16, 2025 at 6:01=E2=80=AFPM Alexei Starovoitov > wrote: > > On Thu, Oct 16, 2025 at 1:51=E2=80=AFPM Paul Moore wrote: > > > On Sun, Oct 12, 2025 at 10:12=E2=80=AFPM Paul Moore wrote: > > > > On Sat, Oct 11, 2025 at 1:09=E2=80=AFPM James Bottomley > > > > wrote: > > > > > On Sat, 2025-10-11 at 09:31 -0700, Alexei Starovoitov wrote: > > > > > > On Sat, Oct 11, 2025 at 7:52=E2=80=AFAM James Bottomley > > > > > > 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 an= d > > > > > > > relocate the map into the bpf program > > > > > > > > > > > > You should read KP's cover letter again and then research trust= ed > > > > > > 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 ha= sh > > > > > > 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 ha= sh > > > > > chains. The security argument isn't about whether the hash chain > > > > > algorithm works, it's about where, in relation to the LSM hook, t= he > > > > > 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.