diff options
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 277d71239d75..bc86f9735f45 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket @@ -7,18 +8,12 @@ * * IPv4 specific functions * - * * code split from: * linux/ipv4/tcp.c * linux/ipv4/tcp_input.c * linux/ipv4/tcp_output.c * * See tcp.c for author information - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. */ /* @@ -1673,7 +1668,9 @@ bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) if (TCP_SKB_CB(tail)->end_seq != TCP_SKB_CB(skb)->seq || TCP_SKB_CB(tail)->ip_dsfield != TCP_SKB_CB(skb)->ip_dsfield || ((TCP_SKB_CB(tail)->tcp_flags | - TCP_SKB_CB(skb)->tcp_flags) & TCPHDR_URG) || + TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_SYN | TCPHDR_RST | TCPHDR_URG)) || + !((TCP_SKB_CB(tail)->tcp_flags & + TCP_SKB_CB(skb)->tcp_flags) & TCPHDR_ACK) || ((TCP_SKB_CB(tail)->tcp_flags ^ TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_ECE | TCPHDR_CWR)) || #ifdef CONFIG_TLS_DEVICE @@ -1692,6 +1689,15 @@ bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) if (after(TCP_SKB_CB(skb)->ack_seq, TCP_SKB_CB(tail)->ack_seq)) TCP_SKB_CB(tail)->ack_seq = TCP_SKB_CB(skb)->ack_seq; + /* We have to update both TCP_SKB_CB(tail)->tcp_flags and + * thtail->fin, so that the fast path in tcp_rcv_established() + * is not entered if we append a packet with a FIN. + * SYN, RST, URG are not present. + * ACK is set on both packets. + * PSH : we do not really care in TCP stack, + * at least for 'GRO' packets. + */ + thtail->fin |= th->fin; TCP_SKB_CB(tail)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; if (TCP_SKB_CB(skb)->has_rxtstamp) { @@ -1774,6 +1780,7 @@ static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph, int tcp_v4_rcv(struct sk_buff *skb) { struct net *net = dev_net(skb->dev); + struct sk_buff *skb_to_free; int sdif = inet_sdif(skb); const struct iphdr *iph; const struct tcphdr *th; @@ -1905,11 +1912,17 @@ process: tcp_segs_in(tcp_sk(sk), skb); ret = 0; if (!sock_owned_by_user(sk)) { + skb_to_free = sk->sk_rx_skb_cache; + sk->sk_rx_skb_cache = NULL; ret = tcp_v4_do_rcv(sk, skb); - } else if (tcp_add_backlog(sk, skb)) { - goto discard_and_relse; + } else { + if (tcp_add_backlog(sk, skb)) + goto discard_and_relse; + skb_to_free = NULL; } bh_unlock_sock(sk); + if (skb_to_free) + __kfree_skb(skb_to_free); put_and_return: if (refcounted) @@ -2578,7 +2591,8 @@ static void __net_exit tcp_sk_exit(struct net *net) { int cpu; - module_put(net->ipv4.tcp_congestion_control->owner); + if (net->ipv4.tcp_congestion_control) + module_put(net->ipv4.tcp_congestion_control->owner); for_each_possible_cpu(cpu) inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv4.tcp_sk, cpu)); |