Re: [PATCH] selftests: livepatch: Fix it to do root uid check and skip

[Petr Mladek]

On Thu 2019-12-12 18:56:17, Shuah Khan wrote:
> livepatch test configures the system and debug environment to run
> tests. Some of these actions fail without root access and test
> dumps several permission denied messages before it exits.
> 
> Fix it to check root uid and exit with skip code instead.

It works when I run the tests directly, e.g.

$> cd tools/testing/selftests/livepatch
$> ./test-livepatch.sh

But I still get an error from the selftest framework when running
make run_tests:

$> make run_tests
TAP version 13
1..5
# selftests: livepatch: test-livepatch.sh
/mnt/kernel/linux/tools/testing/selftests/kselftest/runner.sh: line 43: /dev/stdout: Permission denied
not ok 1 selftests: livepatch: test-livepatch.sh # exit=1
# selftests: livepatch: test-callbacks.sh
/mnt/kernel/linux/tools/testing/selftests/kselftest/runner.sh: line 43: /dev/stdout: Permission denied
not ok 2 selftests: livepatch: test-callbacks.sh # exit=1
# selftests: livepatch: test-shadow-vars.sh
/mnt/kernel/linux/tools/testing/selftests/kselftest/runner.sh: line 43: /dev/stdout: Permission denied
not ok 3 selftests: livepatch: test-shadow-vars.sh # exit=1
# selftests: livepatch: test-state.sh
/mnt/kernel/linux/tools/testing/selftests/kselftest/runner.sh: line 43: /dev/stdout: Permission denied
not ok 4 selftests: livepatch: test-state.sh # exit=1
# selftests: livepatch: test-ftrace.sh
/mnt/kernel/linux/tools/testing/selftests/kselftest/runner.sh: line 43: /dev/stdout: Permission denied
not ok 5 selftests: livepatch: test-ftrace.sh # exit=1

The same problem is also in linux-next. Is this a know problem, please?


> Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
> ---
>  tools/testing/selftests/livepatch/functions.sh | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh
> index 31eb09e38729..014b587692f0 100644
> --- a/tools/testing/selftests/livepatch/functions.sh
> +++ b/tools/testing/selftests/livepatch/functions.sh
> @@ -45,6 +57,7 @@ function pop_config() {
>  }
>  
>  function set_dynamic_debug() {
> +	is_root
>          cat <<-EOF > /sys/kernel/debug/dynamic_debug/control
>  		file kernel/livepatch/* +p
>  		func klp_try_switch_task -p

This test is superfluous.

I guess that it was added because of test-state.sh. But it calls
set_dynamic_debug() instead of config_setup() by mistake.
Please, use the patch below instead of the above hunk.

Otherwise, this patch looks good. Thanks for fixing this.
Without the hunk above, and with the patch below, feel free to use:

Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>


Here is the fix of test-state.sh: