diff options
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 57c8af1859c1..670c3dab24f2 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -237,6 +237,16 @@ static void tcp_measure_rcv_mss(struct sock *sk, const struct sk_buff *skb) */ len = skb_shinfo(skb)->gso_size ? : skb->len; if (len >= icsk->icsk_ack.rcv_mss) { + /* Note: divides are still a bit expensive. + * For the moment, only adjust scaling_ratio + * when we update icsk_ack.rcv_mss. + */ + if (unlikely(len != icsk->icsk_ack.rcv_mss)) { + u64 val = (u64)skb->len << TCP_RMEM_TO_WIN_SCALE; + + do_div(val, skb->truesize); + tcp_sk(sk)->scaling_ratio = val ? val : 1; + } icsk->icsk_ack.rcv_mss = min_t(unsigned int, len, tcp_sk(sk)->advmss); /* Account for possibly-removed options */ @@ -287,7 +297,7 @@ static void tcp_incr_quickack(struct sock *sk, unsigned int max_quickacks) icsk->icsk_ack.quick = quickacks; } -void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks) +static void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks) { struct inet_connection_sock *icsk = inet_csk(sk); @@ -295,7 +305,6 @@ void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks) inet_csk_exit_pingpong_mode(sk); icsk->icsk_ack.ato = TCP_ATO_MIN; } -EXPORT_SYMBOL(tcp_enter_quickack_mode); /* Send ACKs quickly, if "quick" count is not exhausted * and the session is not interactive. @@ -727,8 +736,8 @@ void tcp_rcv_space_adjust(struct sock *sk) if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_moderate_rcvbuf) && !(sk->sk_userlocks & SOCK_RCVBUF_LOCK)) { - int rcvmem, rcvbuf; u64 rcvwin, grow; + int rcvbuf; /* minimal window to cope with packet losses, assuming * steady state. Add some cushion because of small variations. @@ -740,12 +749,7 @@ void tcp_rcv_space_adjust(struct sock *sk) do_div(grow, tp->rcvq_space.space); rcvwin += (grow << 1); - rcvmem = SKB_TRUESIZE(tp->advmss + MAX_TCP_HEADER); - while (tcp_win_from_space(sk, rcvmem) < tp->advmss) - rcvmem += 128; - - do_div(rcvwin, tp->advmss); - rcvbuf = min_t(u64, rcvwin * rcvmem, + rcvbuf = min_t(u64, tcp_space_from_win(sk, rcvwin), READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])); if (rcvbuf > sk->sk_rcvbuf) { WRITE_ONCE(sk->sk_rcvbuf, rcvbuf); @@ -4308,10 +4312,16 @@ static inline bool tcp_paws_discard(const struct sock *sk, * (borrowed from freebsd) */ -static inline bool tcp_sequence(const struct tcp_sock *tp, u32 seq, u32 end_seq) +static enum skb_drop_reason tcp_sequence(const struct tcp_sock *tp, + u32 seq, u32 end_seq) { - return !before(end_seq, tp->rcv_wup) && - !after(seq, tp->rcv_nxt + tcp_receive_window(tp)); + if (before(end_seq, tp->rcv_wup)) + return SKB_DROP_REASON_TCP_OLD_SEQUENCE; + + if (after(seq, tp->rcv_nxt + tcp_receive_window(tp))) + return SKB_DROP_REASON_TCP_INVALID_SEQUENCE; + + return SKB_NOT_DROPPED_YET; } /* When we get a reset we do this. */ @@ -5734,7 +5744,8 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, } /* Step 1: check sequence number */ - if (!tcp_sequence(tp, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq)) { + reason = tcp_sequence(tp, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq); + if (reason) { /* RFC793, page 37: "In all states except SYN-SENT, all reset * (RST) segments are validated by checking their SEQ-fields." * And page 69: "If an incoming segment is not acceptable, @@ -5751,7 +5762,6 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, } else if (tcp_reset_check(sk, skb)) { goto reset; } - SKB_DR_SET(reason, TCP_INVALID_SEQUENCE); goto discard; } |