diff --git a/include/net/tcp.h b/include/net/tcp.h index f6f8f032c73e81326790239cf021d2e50414ce1b..27f4c733116dcc84fe9a73994f8482a69dcfc04e 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1437,6 +1437,7 @@ void tcp_free_fastopen_req(struct tcp_sock *tp); extern struct tcp_fastopen_context __rcu *tcp_fastopen_ctx; int tcp_fastopen_reset_cipher(void *key, unsigned int len); +void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb); struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb, struct request_sock *req, struct tcp_fastopen_cookie *foc, diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index 55be6ac70cff3679cd7a80aa9aaac48ac156a203..467d3e98541115b6df47377ef2ead581d2e64fb0 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -124,6 +124,35 @@ static bool tcp_fastopen_cookie_gen(struct request_sock *req, return false; } + +/* If an incoming SYN or SYNACK frame contains a payload and/or FIN, + * queue this additional data / FIN. + */ +void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb) +{ + struct tcp_sock *tp = tcp_sk(sk); + + if (TCP_SKB_CB(skb)->end_seq == tp->rcv_nxt) + return; + + skb = skb_clone(skb, GFP_ATOMIC); + if (!skb) + return; + + skb_dst_drop(skb); + __skb_pull(skb, tcp_hdrlen(skb)); + skb_set_owner_r(skb, sk); + + tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq; + __skb_queue_tail(&sk->sk_receive_queue, skb); + tp->syn_data_acked = 1; + + /* u64_stats_update_begin(&tp->syncp) not needed here, + * as we certainly are not changing upper 32bit value (0) + */ + tp->bytes_received = skb->len; +} + static struct sock *tcp_fastopen_create_child(struct sock *sk, struct sk_buff *skb, struct dst_entry *dst, @@ -132,7 +161,6 @@ static struct sock *tcp_fastopen_create_child(struct sock *sk, struct tcp_sock *tp; struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; struct sock *child; - u32 end_seq; bool own_req; req->num_retrans = 0; @@ -178,35 +206,11 @@ static struct sock *tcp_fastopen_create_child(struct sock *sk, tcp_init_metrics(child); tcp_init_buffer_space(child); - /* Queue the data carried in the SYN packet. - * We used to play tricky games with skb_get(). - * With lockless listener, it is a dead end. - * Do not think about it. - * - * XXX (TFO) - we honor a zero-payload TFO request for now, - * (any reason not to?) but no need to queue the skb since - * there is no data. How about SYN+FIN? - */ - end_seq = TCP_SKB_CB(skb)->end_seq; - if (end_seq != TCP_SKB_CB(skb)->seq + 1) { - struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); - - if (likely(skb2)) { - skb_dst_drop(skb2); - __skb_pull(skb2, tcp_hdrlen(skb)); - skb_set_owner_r(skb2, child); - __skb_queue_tail(&child->sk_receive_queue, skb2); - tp->syn_data_acked = 1; - - /* u64_stats_update_begin(&tp->syncp) not needed here, - * as we certainly are not changing upper 32bit value (0) - */ - tp->bytes_received = end_seq - TCP_SKB_CB(skb)->seq - 1; - } else { - end_seq = TCP_SKB_CB(skb)->seq + 1; - } - } - tcp_rsk(req)->rcv_nxt = tp->rcv_nxt = end_seq; + tp->rcv_nxt = TCP_SKB_CB(skb)->seq + 1; + + tcp_fastopen_add_skb(child, skb); + + tcp_rsk(req)->rcv_nxt = tp->rcv_nxt; /* tcp_conn_request() is sending the SYNACK, * and queues the child into listener accept queue. */ diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 1c2a73406261921fbea84333eabe3867106f980a..4add3eb40e58aea127aea7c704e2ecf1b174ef78 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5509,6 +5509,9 @@ static bool tcp_rcv_fastopen_synack(struct sock *sk, struct sk_buff *synack, tp->syn_data_acked = tp->syn_data; if (tp->syn_data_acked) NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPFASTOPENACTIVE); + + tcp_fastopen_add_skb(sk, synack); + return false; }