diff options
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 7d2dc015cd19..6451b83d81e9 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2944,7 +2944,7 @@ int tcp_send_synack(struct sock *sk) struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, struct request_sock *req, struct tcp_fastopen_cookie *foc, - bool attach_req) + enum tcp_synack_type synack_type) { struct inet_request_sock *ireq = inet_rsk(req); const struct tcp_sock *tp = tcp_sk(sk); @@ -2964,14 +2964,22 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, /* Reserve space for headers. */ skb_reserve(skb, MAX_TCP_HEADER); - if (attach_req) { + switch (synack_type) { + case TCP_SYNACK_NORMAL: skb_set_owner_w(skb, req_to_sk(req)); - } else { + break; + case TCP_SYNACK_COOKIE: + /* Under synflood, we do not attach skb to a socket, + * to avoid false sharing. + */ + break; + case TCP_SYNACK_FASTOPEN: /* sk is a const pointer, because we want to express multiple * cpu might call us concurrently. * sk->sk_wmem_alloc in an atomic, we can promote to rw. */ skb_set_owner_w(skb, (struct sock *)sk); + break; } skb_dst_set(skb, dst); @@ -3516,7 +3524,7 @@ int tcp_rtx_synack(const struct sock *sk, struct request_sock *req) int res; tcp_rsk(req)->txhash = net_tx_rndhash(); - res = af_ops->send_synack(sk, NULL, &fl, req, NULL, true); + res = af_ops->send_synack(sk, NULL, &fl, req, NULL, TCP_SYNACK_NORMAL); if (!res) { TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS); NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPSYNRETRANS); |