On 7/4/25 10:53 AM, chia-yu.chang@xxxxxxxxxxxxxxxxxxx wrote:
> @@ -1151,7 +1155,10 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb
> }
>
> if (tcp_ecn_mode_accecn(tp) &&
> - READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_ecn_option)) {
> + READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_ecn_option) &&
> + (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_ecn_option) >= TCP_ACCECN_OPTION_FULL ||
> + tp->accecn_opt_demand ||
> + tcp_accecn_option_beacon_check(sk))) {
> opts->use_synack_ecn_bytes = 0;
> size += tcp_options_fit_accecn(opts, tp->accecn_minlen,
> MAX_TCP_OPTION_SPACE - size);
whoops, I almost missed it...
Please call READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_ecn_option) only
once, i.e.:
if (tcp_ecn_mode_accecn(tp)) {
int ecn_opt = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_ecn_option);
if (ecn_opt && (ecn_opt >= TCP_ACCECN_OPTION_FULL || // ...
/P
