diff options
| author | Willem de Bruijn <willemb@google.com> | 2019-09-12 21:16:39 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-09-21 07:16:43 +0200 |
| commit | fdd60d80c4294b7203d6f9d075a57da0a8d85fba (patch) | |
| tree | 88b4a9c352f80f3793007c5e76bb487867784b30 /net/core | |
| parent | 97b5f8c95b75817f0ab27438e8dab136a3ae9ae8 (diff) | |
udp: correct reuseport selection with connected sockets
[ Upstream commit acdcecc61285faed359f1a3568c32089cc3a8329 ]
UDP reuseport groups can hold a mix unconnected and connected sockets.
Ensure that connections only receive all traffic to their 4-tuple.
Fast reuseport returns on the first reuseport match on the assumption
that all matches are equal. Only if connections are present, return to
the previous behavior of scoring all sockets.
Record if connections are present and if so (1) treat such connected
sockets as an independent match from the group, (2) only return
2-tuple matches from reuseport and (3) do not return on the first
2-tuple reuseport match to allow for a higher scoring match later.
New field has_conns is set without locks. No other fields in the
bitmap are modified at runtime and the field is only ever set
unconditionally, so an RMW cannot miss a change.
Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection")
Link: http://lkml.kernel.org/r/CA+FuTSfRP09aJNYRt04SS6qj22ViiOEWaWmLAwX0psk8-PGNxw@mail.gmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Craig Gallek <kraig@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/sock_reuseport.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c index ba5cba56f574..fd38cf1d2b02 100644 --- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -292,8 +292,19 @@ struct sock *reuseport_select_sock(struct sock *sk, select_by_hash: /* no bpf or invalid bpf result: fall back to hash usage */ - if (!sk2) - sk2 = reuse->socks[reciprocal_scale(hash, socks)]; + if (!sk2) { + int i, j; + + i = j = reciprocal_scale(hash, socks); + while (reuse->socks[i]->sk_state == TCP_ESTABLISHED) { + i++; + if (i >= reuse->num_socks) + i = 0; + if (i == j) + goto out; + } + sk2 = reuse->socks[i]; + } } out: |