From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752780AbbFRGlf (ORCPT ); Thu, 18 Jun 2015 02:41:35 -0400 Received: from ozlabs.org ([103.22.144.67]:46084 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752438AbbFRGl1 (ORCPT ); Thu, 18 Jun 2015 02:41:27 -0400 Message-ID: <1434609685.25157.5.camel@ellerman.id.au> Subject: Re: [PATCH] selftests: add seccomp suite From: Michael Ellerman To: Kees Cook Cc: LKML , Daniel Borkmann , Shuah Khan , Andy Lutomirski , Will Drewry , Andrew Morton , Greg KH , Mauro Carvalho Chehab , "David S. Miller" , Arnd Bergmann , Joe Perches , Jingoo Han , Linux API Date: Thu, 18 Jun 2015 16:41:25 +1000 In-Reply-To: References: <20150616175414.GA24958@www.outflux.net> <1434526286.28933.2.camel@ellerman.id.au> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.10-0ubuntu1~14.10.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2015-06-17 at 11:12 -0700, Kees Cook wrote: > On Wed, Jun 17, 2015 at 12:31 AM, Michael Ellerman 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 > >> --- > >> 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. Yeah I did add a change_syscall() implementation, patch below. > 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. Yeah I saw that too, and I think you're probably right that's where the problem is. It doesn't seem to matter what I put in SYSCALL_RET I always get -1, so I think there's a bug in my kernel code. Will try and work it out tonight. cheers diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c index c5abe7fd7590..1bced19c54fb 100644 --- a/tools/testing/selftests/seccomp/seccomp_bpf.c +++ b/tools/testing/selftests/seccomp/seccomp_bpf.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -1199,6 +1200,10 @@ TEST_F(TRACE_poke, getpid_runs_normally) # define ARCH_REGS struct user_pt_regs # define SYSCALL_NUM regs[8] # define SYSCALL_RET regs[0] +#elif defined(__powerpc__) +# define ARCH_REGS struct pt_regs +# define SYSCALL_NUM gpr[0] +# define SYSCALL_RET gpr[3] #else # error "Do not know how to find your architecture's registers and syscalls" #endif @@ -1246,6 +1251,10 @@ void change_syscall(struct __test_metadata *_metadata, EXPECT_EQ(0, ret); } +#elif defined(__powerpc__) + { + regs.SYSCALL_NUM = syscall; + } #else ASSERT_EQ(1, 0) { TH_LOG("How is the syscall changed on this architecture?"); @@ -1396,6 +1405,8 @@ TEST_F(TRACE_syscall, syscall_dropped) # define __NR_seccomp 383 # elif defined(__aarch64__) # define __NR_seccomp 277 +# elif defined(__powerpc__) +# define __NR_seccomp 358 # else # warning "seccomp syscall number unknown for this architecture" # define __NR_seccomp 0xffff From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Ellerman Subject: Re: [PATCH] selftests: add seccomp suite Date: Thu, 18 Jun 2015 16:41:25 +1000 Message-ID: <1434609685.25157.5.camel@ellerman.id.au> References: <20150616175414.GA24958@www.outflux.net> <1434526286.28933.2.camel@ellerman.id.au> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Kees Cook Cc: LKML , Daniel Borkmann , Shuah Khan , Andy Lutomirski , Will Drewry , Andrew Morton , Greg KH , Mauro Carvalho Chehab , "David S. Miller" , Arnd Bergmann , Joe Perches , Jingoo Han , Linux API List-Id: linux-api@vger.kernel.org On Wed, 2015-06-17 at 11:12 -0700, Kees Cook wrote: > On Wed, Jun 17, 2015 at 12:31 AM, Michael Ellerman 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 > >> --- > >> 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. Yeah I did add a change_syscall() implementation, patch below. > 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. Yeah I saw that too, and I think you're probably right that's where the problem is. It doesn't seem to matter what I put in SYSCALL_RET I always get -1, so I think there's a bug in my kernel code. Will try and work it out tonight. cheers diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c index c5abe7fd7590..1bced19c54fb 100644 --- a/tools/testing/selftests/seccomp/seccomp_bpf.c +++ b/tools/testing/selftests/seccomp/seccomp_bpf.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -1199,6 +1200,10 @@ TEST_F(TRACE_poke, getpid_runs_normally) # define ARCH_REGS struct user_pt_regs # define SYSCALL_NUM regs[8] # define SYSCALL_RET regs[0] +#elif defined(__powerpc__) +# define ARCH_REGS struct pt_regs +# define SYSCALL_NUM gpr[0] +# define SYSCALL_RET gpr[3] #else # error "Do not know how to find your architecture's registers and syscalls" #endif @@ -1246,6 +1251,10 @@ void change_syscall(struct __test_metadata *_metadata, EXPECT_EQ(0, ret); } +#elif defined(__powerpc__) + { + regs.SYSCALL_NUM = syscall; + } #else ASSERT_EQ(1, 0) { TH_LOG("How is the syscall changed on this architecture?"); @@ -1396,6 +1405,8 @@ TEST_F(TRACE_syscall, syscall_dropped) # define __NR_seccomp 383 # elif defined(__aarch64__) # define __NR_seccomp 277 +# elif defined(__powerpc__) +# define __NR_seccomp 358 # else # warning "seccomp syscall number unknown for this architecture" # define __NR_seccomp 0xffff