From d9d024f96609016628d750ebc8ee4a6f0d80e6e1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 15 Apr 2022 17:10:39 -0700 Subject: [PATCH] tcp: consume incoming skb leading to a reset Whenever tcp_validate_incoming() handles a valid RST packet, we should not pretend the packet was dropped. Create a special section at the end of tcp_validate_incoming() to handle this case. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 1595b76ea2bea..d4bc717791704 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5700,7 +5700,7 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, &tp->last_oow_ack_time)) tcp_send_dupack(sk, skb); } else if (tcp_reset_check(sk, skb)) { - tcp_reset(sk, skb); + goto reset; } goto discard; } @@ -5736,17 +5736,16 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb, } if (rst_seq_match) - tcp_reset(sk, skb); - else { - /* Disable TFO if RST is out-of-order - * and no data has been received - * for current active TFO socket - */ - if (tp->syn_fastopen && !tp->data_segs_in && - sk->sk_state == TCP_ESTABLISHED) - tcp_fastopen_active_disable(sk); - tcp_send_challenge_ack(sk); - } + goto reset; + + /* Disable TFO if RST is out-of-order + * and no data has been received + * for current active TFO socket + */ + if (tp->syn_fastopen && !tp->data_segs_in && + sk->sk_state == TCP_ESTABLISHED) + tcp_fastopen_active_disable(sk); + tcp_send_challenge_ack(sk); goto discard; } @@ -5771,6 +5770,11 @@ syn_challenge: discard: tcp_drop(sk, skb); return false; + +reset: + tcp_reset(sk, skb); + __kfree_skb(skb); + return false; } /* -- 2.30.2