[PATCH v3 4/6] selftest/Landlock: pthread_kill(3) tests

[Mickaël Salaün]

Please make sure all subject's prefixes are correct, there is two errors
in the prefix and the description can be made more consistent with other
patches, something like this: "selftests/landlock: Add
signal_scoping_threads test"

On Thu, Aug 15, 2024 at 12:29:23PM -0600, Tahera Fahimi wrote:
> This patch expands the signal scoping tests with pthread_kill(3)
> It tests if an scoped thread can send signal to a process in
> the same scoped domain, or a non-sandboxed thread.
> 
> Signed-off-by: Tahera Fahimi <fahimitahera at gmail.com>
> ---
>  .../selftests/landlock/scoped_signal_test.c   | 29 +++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/tools/testing/selftests/landlock/scoped_signal_test.c b/tools/testing/selftests/landlock/scoped_signal_test.c
> index 92958c6266ca..2edba1e6cd82 100644
> --- a/tools/testing/selftests/landlock/scoped_signal_test.c
> +++ b/tools/testing/selftests/landlock/scoped_signal_test.c
> @@ -10,6 +10,7 @@
>  #include <errno.h>
>  #include <fcntl.h>
>  #include <linux/landlock.h>
> +#include <pthread.h>
>  #include <signal.h>
>  #include <sys/prctl.h>
>  #include <sys/types.h>
> @@ -18,6 +19,7 @@
>  
>  #include "common.h"
>  
> +#define DEFAULT_THREAD_RUNTIME 0.001
>  static sig_atomic_t signaled;
>  
>  static void create_signal_domain(struct __test_metadata *const _metadata)
> @@ -299,4 +301,31 @@ TEST_F(signal_scoping, test_signal)
>  		_metadata->exit_code = KSFT_FAIL;
>  }
>  
> +static void *thread_func(void *arg)
> +{
> +	sleep(DEFAULT_THREAD_RUNTIME);

Using sleep() may make this test flaky.  It needs to be removed and the
test should work the same.

> +	return NULL;
> +}
> +
> +TEST(signal_scoping_threads)
> +{
> +	pthread_t no_sandbox_thread, scoped_thread;
> +	int err;
> +
> +	ASSERT_EQ(0,
> +		  pthread_create(&no_sandbox_thread, NULL, thread_func, NULL));
> +	create_signal_domain(_metadata);
> +	ASSERT_EQ(0, pthread_create(&scoped_thread, NULL, thread_func, NULL));
> +
> +	/* Send signal to threads */
> +	err = pthread_kill(no_sandbox_thread, 0);
> +	ASSERT_EQ(EPERM, err);
> +
> +	err = pthread_kill(scoped_thread, 0);
> +	ASSERT_EQ(0, err);
> +
> +	ASSERT_EQ(0, pthread_join(scoped_thread, NULL));
> +	ASSERT_EQ(0, pthread_join(no_sandbox_thread, NULL));
> +}
> +
>  TEST_HARNESS_MAIN
> -- 
> 2.34.1
> 
>