Re: [PATCH bpf-next v5 15/15] selftests/bpf: Tests for BPF_SK_LOOKUP attach point

On Fri, Jul 17, 2020 at 3:36 AM Jakub Sitnicki [off-list ref] 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:

  bash-5.0# ./test_progs -n 70
  #70/1 query lookup prog:OK
  #70/2 TCP IPv4 redir port:OK
  #70/3 TCP IPv4 redir addr:OK
  #70/4 TCP IPv4 redir with reuseport:OK
  #70/5 TCP IPv4 redir skip reuseport:OK
  #70/6 TCP IPv6 redir port:OK
  #70/7 TCP IPv6 redir addr:OK
  #70/8 TCP IPv4->IPv6 redir port:OK
  #70/9 TCP IPv6 redir with reuseport:OK
  #70/10 TCP IPv6 redir skip reuseport:OK
  #70/11 UDP IPv4 redir port:OK
  #70/12 UDP IPv4 redir addr:OK
  #70/13 UDP IPv4 redir with reuseport:OK
  #70/14 UDP IPv4 redir skip reuseport:OK
  #70/15 UDP IPv6 redir port:OK
  #70/16 UDP IPv6 redir addr:OK
  #70/17 UDP IPv4->IPv6 redir port:OK
  #70/18 UDP IPv6 redir and reuseport:OK
  #70/19 UDP IPv6 redir skip reuseport:OK
  #70/20 TCP IPv4 drop on lookup:OK
  #70/21 TCP IPv6 drop on lookup:OK
  #70/22 UDP IPv4 drop on lookup:OK
  #70/23 UDP IPv6 drop on lookup:OK
  #70/24 TCP IPv4 drop on reuseport:OK
  #70/25 TCP IPv6 drop on reuseport:OK
  #70/26 UDP IPv4 drop on reuseport:OK
  #70/27 TCP IPv6 drop on reuseport:OK
  #70/28 sk_assign returns EEXIST:OK
  #70/29 sk_assign honors F_REPLACE:OK
  #70/30 sk_assign accepts NULL socket:OK
  #70/31 access ctx->sk:OK
  #70/32 narrow access to ctx v4:OK
  #70/33 narrow access to ctx v6:OK
  #70/34 sk_assign rejects TCP established:OK
  #70/35 sk_assign rejects UDP connected:OK
  #70/36 multi prog - pass, pass:OK
  #70/37 multi prog - drop, drop:OK
  #70/38 multi prog - pass, drop:OK
  #70/39 multi prog - drop, pass:OK
  #70/40 multi prog - pass, redir:OK
  #70/41 multi prog - redir, pass:OK
  #70/42 multi prog - drop, redir:OK
  #70/43 multi prog - redir, drop:OK
  #70/44 multi prog - redir, redir:OK
  #70 sk_lookup:OK
  Summary: 1/44 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
---

Hey Jakub!

We are getting this failure in Travis CI when syncing libbpf [0]:

ip: either "local" is duplicate, or "nodad" is garbage

switch_netns:PASS:unshare 0 nsec

switch_netns:FAIL:system failed

(/home/travis/build/libbpf/libbpf/travis-ci/vmtest/bpf-next/tools/testing/selftests/bpf/prog_tests/sk_lookup.c:1310:
errno: No such file or directory) system(ip -6 addr add dev lo
fd00::1/128 nodad)

#73 sk_lookup:FAIL

Can you please help fix it so that it works in a Travis CI environment
as well? For now I disabled sk_lookup selftests altogether. You can
try to repro it locally by forking https://github.com/libbpf/libbpf
and enabling Travis CI for your account. See [1] for the PR that
disabled sk_lookup.


  [0] https://travis-ci.com/github/libbpf/libbpf/jobs/365878309#L5408
  [1] https://github.com/libbpf/libbpf/pull/182/commits/78368c2eaed8b0681381fc34d6016c9b5a443be8


Thanks for your help!