* congestion control: Linux DCTCP asserts ECT on all packets,
* including SYN, which is most optimal solution; however,
* others, such as FreeBSD do not.
+ *
+ * Exception: At least one of the reserved bits of the TCP header (th->res1) is
+ * set, indicating the use of a future TCP extension (such as AccECN). See
+ * RFC8311 ยง4.3 which updates RFC3168 to allow the development of such
+ * extensions.
*/
static void tcp_ecn_create_request(struct request_sock *req,
const struct sk_buff *skb,
ecn_ok_dst = dst_feature(dst, DST_FEATURE_ECN_MASK);
ecn_ok = net->ipv4.sysctl_tcp_ecn || ecn_ok_dst;
- if ((!ect && ecn_ok) || tcp_ca_needs_ecn(listen_sk) ||
+ if (((!ect || th->res1) && ecn_ok) || tcp_ca_needs_ecn(listen_sk) ||
(ecn_ok_dst & DST_FEATURE_ECN_CA) ||
tcp_bpf_ca_needs_ecn((struct sock *)req))
inet_rsk(req)->ecn_ok = 1;
reqsk_fastopen_remove(fastopen_sk, req, false);
bh_unlock_sock(fastopen_sk);
sock_put(fastopen_sk);
- reqsk_put(req);
- goto drop;
+ goto drop_and_free;
}
sk->sk_data_ready(sk);
bh_unlock_sock(fastopen_sk);
drop_and_release:
dst_release(dst);
drop_and_free:
- reqsk_free(req);
+ __reqsk_free(req);
drop:
tcp_listendrop(sk);
return 0;