[PATCH v5 08/10] selftests/harness: Share _metadata between forked processes

Mickaël Salaün
2024-05-03T10:58:41Z

Unconditionally share _metadata between all forked processes, which
enables to actually catch errors which were previously ignored.

This is required for a following commit replacing vfork() with clone3()
and CLONE_VFORK (i.e. not sharing the full memory) . It should also be
useful to share _metadata to extend expectations to test process's
forks. For instance, this change identified a wrong expectation in
pidfd_setns_test.

Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Will Drewry <wad@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Link: https://lore.kernel.org/r/20240503105820.300927-9-mic@digikod.net
---

Changes since v4:
* Reset _metadata's aborted and setup_completed fields.

Changes since v1:
* Extract change from a bigger patch (suggested by Kees).
---
tools/testing/selftests/kselftest_harness.h | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 201040207c85..ea78bec5856f 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -430,19 +430,17 @@ static inline pid_t clone3_vfork(void)
kill(getpid(), WTERMSIG(status)); \
__test_check_assert(_metadata); \
} \
- static struct __test_metadata \
- _##fixture_name##_##test_name##_object = { \
- .name = #test_name, \
- .fn = &wrapper_##fixture_name##_##test_name, \
- .fixture = &_##fixture_name##_fixture_object, \
- .termsig = signal, \
- .timeout = tmout, \
- .teardown_parent = false, \
- }; \
static void __attribute__((constructor)) \
_register_##fixture_name##_##test_name(void) \
{ \
- __register_test(&_##fixture_name##_##test_name##_object); \
+ struct __test_metadata *object = mmap(NULL, sizeof(*object), \
+ PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); \
+ object->name = #test_name; \
+ object->fn = &wrapper_##fixture_name##_##test_name; \
+ object->fixture = &_##fixture_name##_fixture_object; \
+ object->termsig = signal; \
+ object->timeout = tmout; \
+ __register_test(object); \
} \
static void fixture_name##_##test_name( \
struct __test_metadata __attribute__((unused)) *_metadata, \
@@ -1181,6 +1179,9 @@ void __run_test(struct __fixture_metadata *f,
/* reset test struct */
t->exit_code = KSFT_PASS;
t->trigger = 0;
+ t->aborted = false;
+ t->setup_completed = false;
+ memset(t->env, 0, sizeof(t->env));
memset(t->results->reason, 0, sizeof(t->results->reason));

if (asprintf(&test_name, "%s%s%s.%s", f->name,
--
2.45.0