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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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tcp: remove one indentation level in tcp_rcv_state_process()
Remove one level of indentation 'introduced' in commit
c3ae62af8e
(tcp: should drop incoming frames without ACK flag set)
if (true) {
...
}
@acceptable variable is a boolean.
This patch is a pure cleanup.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
42e52bf9e3
commit
1f6afc8108
1 changed files with 136 additions and 139 deletions
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@ -5536,6 +5536,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
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struct inet_connection_sock *icsk = inet_csk(sk);
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struct request_sock *req;
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int queued = 0;
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bool acceptable;
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tp->rx_opt.saw_tstamp = 0;
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@ -5606,157 +5607,153 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
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return 0;
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/* step 5: check the ACK field */
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if (true) {
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int acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH |
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FLAG_UPDATE_TS_RECENT) > 0;
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acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH |
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FLAG_UPDATE_TS_RECENT) > 0;
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switch (sk->sk_state) {
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case TCP_SYN_RECV:
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if (acceptable) {
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/* Once we leave TCP_SYN_RECV, we no longer
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* need req so release it.
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*/
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if (req) {
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tcp_synack_rtt_meas(sk, req);
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tp->total_retrans = req->num_retrans;
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reqsk_fastopen_remove(sk, req, false);
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} else {
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/* Make sure socket is routed, for
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* correct metrics.
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*/
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icsk->icsk_af_ops->rebuild_header(sk);
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tcp_init_congestion_control(sk);
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tcp_mtup_init(sk);
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tcp_init_buffer_space(sk);
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tp->copied_seq = tp->rcv_nxt;
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}
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smp_mb();
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tcp_set_state(sk, TCP_ESTABLISHED);
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sk->sk_state_change(sk);
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/* Note, that this wakeup is only for marginal
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* crossed SYN case. Passively open sockets
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* are not waked up, because sk->sk_sleep ==
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* NULL and sk->sk_socket == NULL.
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*/
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if (sk->sk_socket)
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sk_wake_async(sk,
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SOCK_WAKE_IO, POLL_OUT);
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tp->snd_una = TCP_SKB_CB(skb)->ack_seq;
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tp->snd_wnd = ntohs(th->window) <<
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tp->rx_opt.snd_wscale;
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tcp_init_wl(tp, TCP_SKB_CB(skb)->seq);
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if (tp->rx_opt.tstamp_ok)
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tp->advmss -= TCPOLEN_TSTAMP_ALIGNED;
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if (req) {
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/* Re-arm the timer because data may
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* have been sent out. This is similar
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* to the regular data transmission case
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* when new data has just been ack'ed.
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*
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* (TFO) - we could try to be more
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* aggressive and retranmitting any data
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* sooner based on when they were sent
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* out.
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*/
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tcp_rearm_rto(sk);
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} else
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tcp_init_metrics(sk);
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/* Prevent spurious tcp_cwnd_restart() on
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* first data packet.
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*/
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tp->lsndtime = tcp_time_stamp;
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tcp_initialize_rcv_mss(sk);
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tcp_fast_path_on(tp);
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} else {
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return 1;
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}
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break;
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case TCP_FIN_WAIT1:
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/* If we enter the TCP_FIN_WAIT1 state and we are a
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* Fast Open socket and this is the first acceptable
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* ACK we have received, this would have acknowledged
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* our SYNACK so stop the SYNACK timer.
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switch (sk->sk_state) {
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case TCP_SYN_RECV:
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if (acceptable) {
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/* Once we leave TCP_SYN_RECV, we no longer
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* need req so release it.
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*/
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if (req != NULL) {
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/* Return RST if ack_seq is invalid.
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* Note that RFC793 only says to generate a
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* DUPACK for it but for TCP Fast Open it seems
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* better to treat this case like TCP_SYN_RECV
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* above.
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*/
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if (!acceptable)
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return 1;
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/* We no longer need the request sock. */
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if (req) {
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tcp_synack_rtt_meas(sk, req);
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tp->total_retrans = req->num_retrans;
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reqsk_fastopen_remove(sk, req, false);
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tcp_rearm_rto(sk);
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} else {
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/* Make sure socket is routed, for
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* correct metrics.
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*/
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icsk->icsk_af_ops->rebuild_header(sk);
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tcp_init_congestion_control(sk);
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tcp_mtup_init(sk);
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tcp_init_buffer_space(sk);
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tp->copied_seq = tp->rcv_nxt;
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}
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if (tp->snd_una == tp->write_seq) {
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struct dst_entry *dst;
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smp_mb();
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tcp_set_state(sk, TCP_ESTABLISHED);
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sk->sk_state_change(sk);
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tcp_set_state(sk, TCP_FIN_WAIT2);
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sk->sk_shutdown |= SEND_SHUTDOWN;
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/* Note, that this wakeup is only for marginal
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* crossed SYN case. Passively open sockets
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* are not waked up, because sk->sk_sleep ==
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* NULL and sk->sk_socket == NULL.
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*/
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if (sk->sk_socket)
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sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT);
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dst = __sk_dst_get(sk);
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if (dst)
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dst_confirm(dst);
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tp->snd_una = TCP_SKB_CB(skb)->ack_seq;
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tp->snd_wnd = ntohs(th->window) <<
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tp->rx_opt.snd_wscale;
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tcp_init_wl(tp, TCP_SKB_CB(skb)->seq);
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if (!sock_flag(sk, SOCK_DEAD))
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/* Wake up lingering close() */
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sk->sk_state_change(sk);
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else {
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int tmo;
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if (tp->rx_opt.tstamp_ok)
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tp->advmss -= TCPOLEN_TSTAMP_ALIGNED;
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if (tp->linger2 < 0 ||
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(TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&
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after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt))) {
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tcp_done(sk);
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NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
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return 1;
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}
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if (req) {
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/* Re-arm the timer because data may
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* have been sent out. This is similar
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* to the regular data transmission case
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* when new data has just been ack'ed.
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*
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* (TFO) - we could try to be more aggressive
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* and retransmitting any data sooner based
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* on when they are sent out.
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*/
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tcp_rearm_rto(sk);
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} else
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tcp_init_metrics(sk);
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tmo = tcp_fin_time(sk);
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if (tmo > TCP_TIMEWAIT_LEN) {
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inet_csk_reset_keepalive_timer(sk, tmo - TCP_TIMEWAIT_LEN);
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} else if (th->fin || sock_owned_by_user(sk)) {
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/* Bad case. We could lose such FIN otherwise.
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* It is not a big problem, but it looks confusing
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* and not so rare event. We still can lose it now,
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* if it spins in bh_lock_sock(), but it is really
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* marginal case.
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*/
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inet_csk_reset_keepalive_timer(sk, tmo);
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} else {
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tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
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goto discard;
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}
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/* Prevent spurious tcp_cwnd_restart() on
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* first data packet.
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*/
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tp->lsndtime = tcp_time_stamp;
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tcp_initialize_rcv_mss(sk);
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tcp_fast_path_on(tp);
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} else {
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return 1;
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}
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break;
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case TCP_FIN_WAIT1:
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/* If we enter the TCP_FIN_WAIT1 state and we are a
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* Fast Open socket and this is the first acceptable
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* ACK we have received, this would have acknowledged
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* our SYNACK so stop the SYNACK timer.
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*/
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if (req != NULL) {
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/* Return RST if ack_seq is invalid.
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* Note that RFC793 only says to generate a
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* DUPACK for it but for TCP Fast Open it seems
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* better to treat this case like TCP_SYN_RECV
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* above.
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*/
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if (!acceptable)
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return 1;
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/* We no longer need the request sock. */
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reqsk_fastopen_remove(sk, req, false);
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tcp_rearm_rto(sk);
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}
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if (tp->snd_una == tp->write_seq) {
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struct dst_entry *dst;
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tcp_set_state(sk, TCP_FIN_WAIT2);
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sk->sk_shutdown |= SEND_SHUTDOWN;
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dst = __sk_dst_get(sk);
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if (dst)
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dst_confirm(dst);
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if (!sock_flag(sk, SOCK_DEAD)) {
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/* Wake up lingering close() */
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sk->sk_state_change(sk);
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} else {
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int tmo;
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if (tp->linger2 < 0 ||
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(TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&
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after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt))) {
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tcp_done(sk);
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NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
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return 1;
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}
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tmo = tcp_fin_time(sk);
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if (tmo > TCP_TIMEWAIT_LEN) {
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inet_csk_reset_keepalive_timer(sk, tmo - TCP_TIMEWAIT_LEN);
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} else if (th->fin || sock_owned_by_user(sk)) {
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/* Bad case. We could lose such FIN otherwise.
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* It is not a big problem, but it looks confusing
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* and not so rare event. We still can lose it now,
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* if it spins in bh_lock_sock(), but it is really
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* marginal case.
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*/
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inet_csk_reset_keepalive_timer(sk, tmo);
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} else {
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tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
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goto discard;
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}
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}
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break;
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case TCP_CLOSING:
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if (tp->snd_una == tp->write_seq) {
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tcp_time_wait(sk, TCP_TIME_WAIT, 0);
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goto discard;
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}
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break;
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case TCP_LAST_ACK:
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if (tp->snd_una == tp->write_seq) {
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tcp_update_metrics(sk);
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tcp_done(sk);
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goto discard;
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}
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break;
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}
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break;
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case TCP_CLOSING:
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if (tp->snd_una == tp->write_seq) {
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tcp_time_wait(sk, TCP_TIME_WAIT, 0);
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goto discard;
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}
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break;
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case TCP_LAST_ACK:
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if (tp->snd_una == tp->write_seq) {
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tcp_update_metrics(sk);
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tcp_done(sk);
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goto discard;
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}
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break;
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}
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/* step 6: check the URG bit */
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