[PATCH v2 RESEND] powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC

[Michael Ellerman]

Paul Moore <paul at paul-moore.com> writes:
> On Tue, Aug 24, 2021 at 1:11 PM Christophe Leroy
> <christophe.leroy at csgroup.eu> wrote:
>> Le 24/08/2021 à 16:47, Paul Moore a écrit :
>> > On Tue, Aug 24, 2021 at 9:36 AM Christophe Leroy
>> > <christophe.leroy at csgroup.eu> wrote:
>> >>
>> >> Commit e65e1fc2d24b ("[PATCH] syscall class hookup for all normal
>> >> targets") added generic support for AUDIT but that didn't include
>> >> support for bi-arch like powerpc.
>> >>
>> >> Commit 4b58841149dc ("audit: Add generic compat syscall support")
>> >> added generic support for bi-arch.
>> >>
>> >> Convert powerpc to that bi-arch generic audit support.
>> >>
>> >> Cc: Paul Moore <paul at paul-moore.com>
>> >> Cc: Eric Paris <eparis at redhat.com>
>> >> Signed-off-by: Christophe Leroy <christophe.leroy at csgroup.eu>
>> >> ---
>> >> Resending v2 with Audit people in Cc
>> >>
>> >> v2:
>> >> - Missing 'git add' for arch/powerpc/include/asm/unistd32.h
>> >> - Finalised commit description
>> >> ---
>> >>   arch/powerpc/Kconfig                |  5 +-
>> >>   arch/powerpc/include/asm/unistd32.h |  7 +++
>> >>   arch/powerpc/kernel/Makefile        |  3 --
>> >>   arch/powerpc/kernel/audit.c         | 84 -----------------------------
>> >>   arch/powerpc/kernel/compat_audit.c  | 44 ---------------
>> >>   5 files changed, 8 insertions(+), 135 deletions(-)
>> >>   create mode 100644 arch/powerpc/include/asm/unistd32.h
>> >>   delete mode 100644 arch/powerpc/kernel/audit.c
>> >>   delete mode 100644 arch/powerpc/kernel/compat_audit.c
>> >
>> > Can you explain, in detail please, the testing you have done to verify
>> > this patch?
>> >
>>
>> I built ppc64_defconfig and checked that the generated code is functionnaly equivalent.
>>
>> ppc32_classify_syscall() is exactly the same as audit_classify_compat_syscall() except that the
>> later takes the syscall as second argument (ie in r4) whereas the former takes it as first argument
>> (ie in r3).
>>
>> audit_classify_arch() and powerpc audit_classify_syscall() are slightly different between the
>> powerpc version and the generic version because the powerpc version checks whether it is
>> AUDIT_ARCH_PPC or not (ie value 20), while the generic one checks whether it has bit
>> __AUDIT_ARCH_64BIT set or not (__AUDIT_ARCH_64BIT is the sign bit of a word), but taking into
>> account that the abi is either AUDIT_ARCH_PPC, AUDIT_ARCH_PPC64 or AUDIT_ARCH_PPC64LE, the result is
>> the same.
>>
>> If you are asking I guess you saw something wrong ?
>
> I was asking because I didn't see any mention of testing, and when you
> are enabling something significant like this it is nice to see that it
> has been verified to work :)
>
> While binary dumps and comparisons are nice, it is always good to see
> verification from a test suite.  I don't have access to the necessary
> hardware to test this, but could you verify that the audit-testsuite
> passes on your test system with your patches applied?
>
>  * https://github.com/linux-audit/audit-testsuite

I tested on ppc64le. Both before and after the patch I get the result
below.

So I guess the patch is OK, but maybe we have some existing issue.

I had a bit of a look at the test code, but my perl is limited. I think
it was running the command below, and it returned "<no matches>", but
not really sure what that means.

  $ sudo ausearch -i -m SYSCALL -p 216440 -ui 0 -gi 0 -ul 0 -su unconfined _u:unconfined_r:unconfined_t:s0-s0:c0.c1023 -ts recent
  <no matches>

cheers



Running as   user    root
        with context unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
        on   system  Fedora

backlog_wait_time_actual_reset/test .. ok
exec_execve/test ..................... ok
exec_name/test ....................... ok
file_create/test ..................... ok
file_delete/test ..................... ok
file_rename/test ..................... ok
filter_exclude/test .................. 1/21
# Test 20 got: "256" (filter_exclude/test at line 167)
#    Expected: "0"
#  filter_exclude/test line 167 is: ok( $result, 0 );
# Test 21 got: "0" (filter_exclude/test at line 179)
#    Expected: "1"
#  filter_exclude/test line 179 is: ok( $found_msg, 1 );
filter_exclude/test .................. Failed 2/21 subtests
filter_saddr_fam/test ................ ok
filter_sessionid/test ................ ok
login_tty/test ....................... ok
lost_reset/test ...................... ok
netfilter_pkt/test ................... ok
syscalls_file/test ................... ok
syscall_module/test .................. ok
time_change/test ..................... ok
user_msg/test ........................ ok
fanotify/test ........................ ok
bpf/test ............................. ok

Test Summary Report
-------------------
filter_exclude/test                (Wstat: 0 Tests: 21 Failed: 2)
  Failed tests:  20-21
Files=18, Tests=202, 45 wallclock secs ( 0.18 usr  0.03 sys + 20.15 cusr  0.92 csys = 21.28 CPU)
Result: FAIL
Failed 1/18 test programs. 2/202 subtests failed.