udp, bpf: Ignore connections in reuseport group after BPF sk lookup

When BPF sk lookup invokes reuseport handling for the selected socket, it
should ignore the fact that reuseport group can contain connected UDP
sockets. With BPF sk lookup this is not relevant as we are not scoring
sockets to find the best match, which might be a connected UDP socket.

Fix it by unconditionally accepting the socket selected by reuseport.

This fixes the following two failures reported by test_progs.

  # ./test_progs -t sk_lookup
  ...
  #73/14 UDP IPv4 redir and reuseport with conns:FAIL
  ...
  #73/20 UDP IPv6 redir and reuseport with conns:FAIL
  ...

Fixes: a57066b1a0 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200726120228.1414348-1-jakub@cloudflare.com
This commit is contained in:
Jakub Sitnicki 2020-07-26 14:02:28 +02:00 committed by Daniel Borkmann
parent 50450fc716
commit c64c9c282a
2 changed files with 2 additions and 2 deletions

View file

@ -473,7 +473,7 @@ static struct sock *udp4_lookup_run_bpf(struct net *net,
return sk;
reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
if (reuse_sk && !reuseport_has_conns(sk, false))
if (reuse_sk)
sk = reuse_sk;
return sk;
}

View file

@ -208,7 +208,7 @@ static inline struct sock *udp6_lookup_run_bpf(struct net *net,
return sk;
reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
if (reuse_sk && !reuseport_has_conns(sk, false))
if (reuse_sk)
sk = reuse_sk;
return sk;
}