Re: [PATCH -next v2] bpf/benchs: Fix return value check of bpf_program__attach()

From: Alexei Starovoitov
Date: Mon Nov 01 2021 - 18:00:27 EST


On Mon, Nov 1, 2021 at 5:35 AM Yang Yingliang <yangyingliang@xxxxxxxxxx> wrote:
>
> If bpf_program__attach() fails, it never returns NULL,
> we should use libbpf_get_error() to check the return value.
>
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
> Acked-by: Yonghong Song <yhs@xxxxxx>
> ---
> v2:
> don't use 'int err'
> ---
> .../selftests/bpf/benchs/bench_bloom_filter_map.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c b/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c
> index 6eeeed2913e6..4afaa4adb327 100644
> --- a/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c
> +++ b/tools/testing/selftests/bpf/benchs/bench_bloom_filter_map.c
> @@ -304,7 +304,7 @@ static void bloom_lookup_setup(void)
> populate_maps();
>
> link = bpf_program__attach(ctx.skel->progs.bloom_lookup);
> - if (!link) {
> + if (libbpf_get_error(link)) {

Please use ASSERT_OK_PTR() instead.
See how other tests are doing it.