diff options
Diffstat (limited to 'net/ipv4/tcp_input.c')
-rw-r--r-- | net/ipv4/tcp_input.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 42bf89a..f9f9e37 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3115,6 +3115,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, long ca_rtt_us = -1L; struct sk_buff *skb; u32 pkts_acked = 0; + u32 last_in_flight = 0; bool rtt_update; int flag = 0; @@ -3154,6 +3155,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, if (!first_ackt.v64) first_ackt = last_ackt; + last_in_flight = TCP_SKB_CB(skb)->tx.in_flight; reord = min(pkts_acked, reord); if (!after(scb->end_seq, tp->high_seq)) flag |= FLAG_ORIG_SACK_ACKED; @@ -3250,7 +3252,8 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, if (icsk->icsk_ca_ops->pkts_acked) { struct ack_sample sample = { .pkts_acked = pkts_acked, - .rtt_us = ca_rtt_us }; + .rtt_us = ca_rtt_us, + .in_flight = last_in_flight }; icsk->icsk_ca_ops->pkts_acked(sk, &sample); } @@ -5169,6 +5172,7 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, const struct tcphdr *th, int syn_inerr) { struct tcp_sock *tp = tcp_sk(sk); + bool rst_seq_match = false; /* RFC1323: H1. Apply PAWS check first. */ if (tcp_fast_parse_options(skb, th, tp) && tp->rx_opt.saw_tstamp && @@ -5205,13 +5209,32 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, /* Step 2: check RST bit */ if (th->rst) { - /* RFC 5961 3.2 : - * If sequence number exactly matches RCV.NXT, then + /* RFC 5961 3.2 (extend to match against SACK too if available): + * If seq num matches RCV.NXT or the right-most SACK block, + * then * RESET the connection * else * Send a challenge ACK */ - if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) + if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) { + rst_seq_match = true; + } else if (tcp_is_sack(tp) && tp->rx_opt.num_sacks > 0) { + struct tcp_sack_block *sp = &tp->selective_acks[0]; + int max_sack = sp[0].end_seq; + int this_sack; + + for (this_sack = 1; this_sack < tp->rx_opt.num_sacks; + ++this_sack) { + max_sack = after(sp[this_sack].end_seq, + max_sack) ? + sp[this_sack].end_seq : max_sack; + } + + if (TCP_SKB_CB(skb)->seq == max_sack) + rst_seq_match = true; + } + + if (rst_seq_match) tcp_reset(sk); else tcp_send_challenge_ack(sk, skb); |