On Sat, May 14, 2022 at 11:31 PM Yuntao Wang <ytcoode@xxxxxxxxx> wrote:
>
> Currently the trampoline_count test doesn't include any fmod_ret bpf
> programs, fix it to make the test cover all possible trampoline program
> types.
>
> Since fmod_ret bpf programs can't be attached to __set_task_comm function,
> as it's neither whitelisted for error injection nor a security hook, change
> it to bpf_modify_return_test.
>
> This patch also does some other cleanups such as removing duplicate code,
> dropping inconsistent comments, etc.
>
> Signed-off-by: Yuntao Wang <ytcoode@xxxxxxxxx>
> ---
> include/linux/bpf.h | 2 +-
> .../bpf/prog_tests/trampoline_count.c | 121 ++++++------------
> .../bpf/progs/test_trampoline_count.c | 16 ++-
> 3 files changed, 47 insertions(+), 92 deletions(-)
>
[...]
>
> /* with E2BIG error */
> - ASSERT_EQ(err, -E2BIG, "proper error check");
> + ASSERT_EQ(libbpf_get_error(link), -E2BIG, "E2BIG");
> ASSERT_EQ(link, NULL, "ptr_is_null");
>
> - /* and finaly execute the probe */
> - if (CHECK_FAIL(prctl(PR_GET_NAME, comm, 0L, 0L, 0L)))
> - goto cleanup_extra;
> - CHECK_FAIL(test_task_rename());
we stopped testing that kernel function actually can be called
properly, why don't you do bpf_prog_test_run() here to trigger
bpf_modify_return_test in kernel?
> - CHECK_FAIL(prctl(PR_SET_NAME, comm, 0L, 0L, 0L));
> -
> -cleanup_extra:
> - bpf_object__close(obj);
> cleanup:
> - if (i >= MAX_TRAMP_PROGS)
> - i = MAX_TRAMP_PROGS - 1;
> for (; i >= 0; i--) {
> - bpf_link__destroy(inst[i].link_fentry);
> - bpf_link__destroy(inst[i].link_fexit);
> + bpf_link__destroy(inst[i].link);
> bpf_object__close(inst[i].obj);
> }
> }
[...]
