[PATCH v2 3/7] seccomp: Allow arch code to provide seccomp_data

[Kees Cook]

On Fri, Jul 18, 2014 at 2:18 PM, Andy Lutomirski <luto at amacapital.net> wrote:
> populate_seccomp_data is expensive: it works by inspecting
> task_pt_regs and various other bits to piece together all the
> information, and it's does so in multiple partially redundant steps.
>
> Arch-specific code in the syscall entry path can do much better.
>
> Admittedly this adds a bit of additional room for error, but the
> speedup should be worth it.

I still think we should gain either a note in the
HAVE_ARCH_SECCOMP_FILTER help text in arch/Kconfig, or possibly a new
section in Documentation/prctl/seccomp.txt (or similar) on how do
implement filter support for an architecture, that mentions the
arch-supplied seccomp_data and how two-phase can be done.

-Kees

-- 
Kees Cook
Chrome OS Security