lkml.org 
[lkml]   [2015]   [Jun]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] selftests: add seccomp suite
From
On Wed, Jun 17, 2015 at 12:31 AM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> On Tue, 2015-06-16 at 10:54 -0700, Kees Cook wrote:
>> This imports the existing seccomp test suite into the kernel's selftests
>> tree. It contains extensive testing of seccomp features and corner cases.
>> There remain additional tests to move into the kernel tree, but they have
>> not yet been ported to all the architectures seccomp supports:
>> https://github.com/redpig/seccomp/tree/master/tests
>>
>> Signed-off-by: Kees Cook <keescook@chromium.org>
>> ---
>> MAINTAINERS | 1 +
>> tools/testing/selftests/Makefile | 1 +
>> tools/testing/selftests/seccomp/.gitignore | 1 +
>> tools/testing/selftests/seccomp/Makefile | 10 +
>> tools/testing/selftests/seccomp/seccomp_bpf.c | 2109 ++++++++++++++++++++++++
>> tools/testing/selftests/seccomp/test_harness.h | 537 ++++++
>
>
> Thanks very much for adding this, it would have been very helpful recently when
> I was trying to get seccomp filter working on powerpc :)
>
> I get one failure in TRACE_syscall.syscall_dropped:
>
> seccomp_bpf.c:1394:TRACE_syscall.syscall_dropped:Expected 1 (1) == syscall(207) (18446744073709551615)
>
>
> So it looks like we're returning -1 instead of 1.
>
> That's probably a bug in our handling of the return value, or maybe an
> inconsistency across the arches. I'll try and find time to dig into it.

Ah-ha! Excellent. Did you add an implementation for change_syscall()
in seccomp_bpf.c? I don't have a powerpc method in there. I would have
expected both TRACE_syscall.syscall_redirected and .syscall_dropped to
fail without that.

If you did, maybe something isn't right with regs.SYSCALL_RET ? That's
where the return value being tested on a skipped syscall is stored.

Thanks for testing!

-Kees

--
Kees Cook
Chrome OS Security


\
 
 \ /
  Last update: 2015-06-17 20:41    [W:0.940 / U:0.300 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site