Commit c8a2983c authored Jul 22, 2020 by Jakub Sitnicki Committed by Alexei Starovoitov Jul 25, 2020

udp: Don't discard reuseport selection when group has connections

When BPF socket lookup prog selects a socket that belongs to a reuseport
group, and the reuseport group has connected sockets in it, the socket
selected by reuseport will be discarded, and socket returned by BPF socket
lookup will be used instead.

Modify this behavior so that the socket selected by reuseport running after
BPF socket lookup always gets used. Ignore the fact that the reuseport
group might have connections because it is only relevant when scoring
sockets during regular hashtable-based lookup.

Fixes: 72f7e944 ("udp: Run SK_LOOKUP BPF program on socket lookup")
Fixes: 6d4201b1 ("udp6: Run SK_LOOKUP BPF program on socket lookup")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/bpf/20200722161720.940831-2-jakub@cloudflare.com

parent f3c93a93

net/ipv6/udp.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -155,9 +155,6 @@ static struct sock lookup_reuseport(struct net net, struct sock *sk,
		hash = udp6_ehashfn(net, daddr, hnum, saddr, sport);
		reuse_sk = reuseport_select_sock(sk, hash, skb,
		sizeof(struct udphdr));
		/* Fall back to scoring if group has connections */
		if (reuseport_has_conns(sk, false))
		return NULL;
		}
		return reuse_sk;
		}

Admin message