From f6c0f5d209fa80eb808e08aa4206f6e264041ef6 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 24 Sep 2019 08:01:16 -0700 Subject: [PATCH] tcp: honor SO_PRIORITY in TIME_WAIT state ctl packets sent on behalf of TIME_WAIT sockets currently have a zero skb->priority, which can cause various problems. In this patch we : - add a tw_priority field in struct inet_timewait_sock. - populate it from sk->sk_priority when a TIME_WAIT is created. - For IPv4, change ip_send_unicast_reply() and its two callers to propagate tw_priority correctly. ip_send_unicast_reply() no longer changes sk->sk_priority. - For IPv6, make sure TIME_WAIT sockets pass their tw_priority field to tcp_v6_send_response() and tcp_v6_send_ack(). Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/inet_timewait_sock.h | 1 + net/ipv4/ip_output.c | 1 - net/ipv4/tcp_ipv4.c | 4 ++++ net/ipv4/tcp_minisocks.c | 1 + net/ipv6/tcp_ipv6.c | 6 ++++-- 5 files changed, 10 insertions(+), 3 deletions(-) diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h index aef38c140014..dfd919b3119e 100644 --- a/include/net/inet_timewait_sock.h +++ b/include/net/inet_timewait_sock.h @@ -71,6 +71,7 @@ struct inet_timewait_sock { tw_pad : 2, /* 2 bits hole */ tw_tos : 8; u32 tw_txhash; + u32 tw_priority; struct timer_list tw_timer; struct inet_bind_bucket *tw_tb; }; diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index a77c3a4c24de..28fca408812c 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -1694,7 +1694,6 @@ void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, inet_sk(sk)->tos = arg->tos; - sk->sk_priority = skb->priority; sk->sk_protocol = ip_hdr(skb)->protocol; sk->sk_bound_dev_if = arg->bound_dev_if; sk->sk_sndbuf = sysctl_wmem_default; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index fd394ad179a0..2ee45e3755e9 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -771,6 +771,8 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) if (sk) { ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ? inet_twsk(sk)->tw_mark : sk->sk_mark; + ctl_sk->sk_priority = (sk->sk_state == TCP_TIME_WAIT) ? + inet_twsk(sk)->tw_priority : sk->sk_priority; transmit_time = tcp_transmit_time(sk); } ip_send_unicast_reply(ctl_sk, @@ -866,6 +868,8 @@ static void tcp_v4_send_ack(const struct sock *sk, ctl_sk = this_cpu_read(*net->ipv4.tcp_sk); ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ? inet_twsk(sk)->tw_mark : sk->sk_mark; + ctl_sk->sk_priority = (sk->sk_state == TCP_TIME_WAIT) ? + inet_twsk(sk)->tw_priority : sk->sk_priority; transmit_time = tcp_transmit_time(sk); ip_send_unicast_reply(ctl_sk, skb, &TCP_SKB_CB(skb)->header.h4.opt, diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 8bcaf2586b68..bb140a5db8c0 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -266,6 +266,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) tw->tw_transparent = inet->transparent; tw->tw_mark = sk->sk_mark; + tw->tw_priority = sk->sk_priority; tw->tw_rcv_wscale = tp->rx_opt.rcv_wscale; tcptw->tw_rcv_nxt = tp->rcv_nxt; tcptw->tw_snd_nxt = tp->snd_nxt; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 5f557bf27da2..e3d9f4559c99 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -995,8 +995,10 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) label = ip6_flowlabel(ipv6h); priority = sk->sk_priority; } - if (sk->sk_state == TCP_TIME_WAIT) + if (sk->sk_state == TCP_TIME_WAIT) { label = cpu_to_be32(inet_twsk(sk)->tw_flowlabel); + priority = inet_twsk(sk)->tw_priority; + } } else { if (net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_TCP_RESET) label = ip6_flowlabel(ipv6h); @@ -1029,7 +1031,7 @@ static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, tcp_time_stamp_raw() + tcptw->tw_ts_offset, tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), - tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel), 0); + tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel), tw->tw_priority); inet_twsk_put(tw); }