Re: [PATCH v13 0/3] Add kernel seccomp support for m68k

[Kees Cook <keescook@chromium.org>]

On Thu, Jan 12, 2023 at 04:55:26PM +1300, Michael Schmitz wrote:
> Previous version of patch 1 did overwrite a syscall return
> value that was changed by ptrace or seccomp (in regs->d0)
> by -ENOSYS when skipping a syscall. Branch directly to
> ret_from_syscall instead of falling through to badsys (which
> must set -ENOSYS). I'm sure this can be done more elegantly.
> 
> Patch 3 used the wrong struct definition for ARCH_REGS - the
> kernel ptrace code copies 19 registers (from syscall stack
> and switch_stack, pt_regs only contains the 14 from the
> syscall stack). Stack overflow ensues.

Hi,

Thanks for expanding seccomp support to m68k! I happened to see this
land in Linus's tree, but it was news to me that it was under
development. Please use scripts/get_maintainers.pl in the future:

SECURE COMPUTING
M:      Kees Cook <keescook@chromium.org>
R:      Andy Lutomirski <luto@amacapital.net>
R:      Will Drewry <wad@chromium.org>
S:      Supported
T:      git git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git for-next/seccomp
F:      Documentation/userspace-api/seccomp_filter.rst
F:      include/linux/seccomp.h
F:      include/uapi/linux/seccomp.h
F:      kernel/seccomp.c
F:      tools/testing/selftests/kselftest_harness.h
F:      tools/testing/selftests/seccomp/*
K:      \bsecure_computing
K:      \bTIF_SECCOMP\b

> With these changes, 79 of 94 seccomp_bpf tests now succeed.

I'm curious which tests are not passing?

Thanks!

-Kees

-- 
Kees Cook