On Mon, Feb 26, 2024 at 05:23:35PM +0100, Mickaël Salaün wrote:
> Remplace Landlock-specific TEST_F_FORK() with an improved TEST_F() which
> brings four related changes:
>
> Run TEST_F()'s tests in a grandchild process to make it possible to
> drop privileges and delegate teardown to the parent.
>
> Compared to TEST_F_FORK(), simplify handling of the test grandchild
> process thanks to vfork(2), and makes it generic (e.g. no explicit
> conversion between exit code and _metadata).
>
> Compared to TEST_F_FORK(), run teardown even when tests failed with an
> assert thanks to commit 63e6b2a42342 ("selftests/harness: Run TEARDOWN
> for ASSERT failures").
>
> Simplify the test harness code by removing the no_print and step fields
> which are not used. I added this feature just after I made
> kselftest_harness.h more broadly available but this step counter
> remained even though it wasn't needed after all. See commit 369130b63178
> ("selftests: Enhance kselftest_harness.h to print which assert failed").
I'm personally fine dropping the step counter. (I do wonder if that
removal should be split from the grandchild launching.)
> Replace spaces with tabs in one line of __TEST_F_IMPL().
>
> Cc: Günther Noack <gnoack@xxxxxxxxxx>
> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc: Shuah Khan <shuah@xxxxxxxxxx>
> Cc: Will Drewry <wad@xxxxxxxxxxxx>
> Signed-off-by: Mickaël Salaün <mic@xxxxxxxxxxx>
One typo below, but otherwise seems good to me:
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> [...]
> _metadata->setup_completed = true; \
> - fixture_name##_##test_name(_metadata, &self, variant->data); \
> + /* Use the same _metadata. */ \
> + child = vfork(); \
> + if (child == 0) { \
> + fixture_name##_##test_name(_metadata, &self, variant->data); \
> + _exit(0); \
> + } \
> + if (child < 0) { \
> + ksft_print_msg("ERROR SPAWNING TEST GANDCHILD\n"); \
typo: GAND -> GRAND
--
Kees Cook
