Re: [PATCH bpf-next v4 16/16] selftests/bpf: Tests for BPF_SK_LOOKUP attach point

From: Andrii Nakryiko <andrii.nakryiko@gmail.com>
To: Jakub Sitnicki <jakub@cloudflare.com>
Cc: bpf <bpf@vger.kernel.org>, Networking <netdev@vger.kernel.org>,
	kernel-team <kernel-team@cloudflare.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>
Subject: Re: [PATCH bpf-next v4 16/16] selftests/bpf: Tests for BPF_SK_LOOKUP attach point
Date: Wed, 15 Jul 2020 19:19:39 -0700	[thread overview]
Message-ID: <CAEf4BzYPk5kNJb61ceWG-22hu47MBuAcMt=itU+xX0mju22NmA@mail.gmail.com> (raw)
In-Reply-To: <20200713174654.642628-17-jakub@cloudflare.com>

On Mon, Jul 13, 2020 at 10:48 AM Jakub Sitnicki <jakub@cloudflare.com> wrote:
>
> Add tests to test_progs that exercise:
>
>  - attaching/detaching/querying programs to BPF_SK_LOOKUP hook,
>  - redirecting socket lookup to a socket selected by BPF program,
>  - failing a socket lookup on BPF program's request,
>  - error scenarios for selecting a socket from BPF program,
>  - accessing BPF program context,
>  - attaching and running multiple BPF programs.
>
> Run log:
>
>   # ./test_progs -n 69
>   #69/1 query lookup prog:OK
>   #69/2 TCP IPv4 redir port:OK

[...]

>   #69/42 multi prog - drop, redir:OK
>   #69/43 multi prog - redir, drop:OK
>   #69/44 multi prog - redir, redir:OK
>   #69 sk_lookup:OK
>   Summary: 1/44 PASSED, 0 SKIPPED, 0 FAILED
>
> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
> ---
>

nit: It's not universal, unfortunately, but the typical naming pattern
for selftest are: progs/test_<something>.c for BPF part, and
prog_tests/<something>.c for user-space part. Just FYI for the future.

But looks good to me either way.

Acked-by: Andrii Nakryiko <andriin@fb.com>

> Notes:
>     v4:
>     - Remove system("bpftool ...") call left over from debugging. (Lorenz)
>     - Dedup BPF code that selects a socket. (Lorenz)
>     - Switch from CHECK_FAIL to CHECK macro. (Andrii)
>     - Extract a network_helper that wraps inet_pton.
>     - Don't restore netns now that test_progs does it.
>     - Cover bpf_sk_assign(ctx, NULL) in tests.
>     - Cover narrow loads in tests.
>     - Cover NULL ctx->sk access attempts in tests.
>     - Cover accessing IPv6 ctx fields on IPv4 lookup.
>
>     v3:
>     - Extend tests to cover new functionality in v3:
>       - multi-prog attachments (query, running, verdict precedence)
>       - socket selecting for the second time with bpf_sk_assign
>       - skipping over reuseport load-balancing
>
>     v2:
>      - Adjust for fields renames in struct bpf_sk_lookup.
>
>  tools/testing/selftests/bpf/network_helpers.c |   58 +-
>  tools/testing/selftests/bpf/network_helpers.h |    2 +
>  .../selftests/bpf/prog_tests/sk_lookup.c      | 1282 +++++++++++++++++
>  .../selftests/bpf/progs/test_sk_lookup_kern.c |  639 ++++++++
>  4 files changed, 1958 insertions(+), 23 deletions(-)
>  create mode 100644 tools/testing/selftests/bpf/prog_tests/sk_lookup.c
>  create mode 100644 tools/testing/selftests/bpf/progs/test_sk_lookup_kern.c
>

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