In case autoflowlabel is in action, skb_get_hash_flowi6()
derives a non zero skb->hash to the flowlabel.
If skb->hash is zero, a flow dissection is performed.
Since all TCP skbs sent from ESTABLISH state inherit their
skb->hash from sk->sk_txhash, we better keep a copy
of sk->sk_txhash into the TIME_WAIT socket.
After this patch, ACK or RST packets sent on behalf of
a TIME_WAIT socket have the flowlabel that was previously
used by the flow.
Signed-off-by: Eric Dumazet <eduma...@google.com>
---
include/net/inet_timewait_sock.h | 1 +
net/ipv4/tcp_minisocks.c | 1 +
net/ipv6/tcp_ipv6.c | 13 ++++++++++---
3 files changed, 12 insertions(+), 3 deletions(-)
diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index
c2f756aedc5453576d67076b20b7c5fa0e64de8a..aef38c140014600dbf88b1d664bad1b0adf63668
100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -70,6 +70,7 @@ struct inet_timewait_sock {
tw_flowlabel : 20,
tw_pad : 2, /* 2 bits hole */
tw_tos : 8;
+ u32 tw_txhash;
struct timer_list tw_timer;
struct inet_bind_bucket *tw_tb;
};
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index
7c35731816e23fe0f82351d3848bf13379efad5f..11011e8386dc97254a752514e4e6f77a068efaf4
100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -283,6 +283,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
tw->tw_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
tw->tw_tclass = np->tclass;
tw->tw_flowlabel = be32_to_cpu(np->flow_label &
IPV6_FLOWLABEL_MASK);
+ tw->tw_txhash = sk->sk_txhash;
tw->tw_ipv6only = sk->sk_ipv6only;
}
#endif
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index
c1da52c7f990f2fa3e020e3f3a33934149ad225e..ad7039137a20f9ad8581d9ca01347c67aa8a8433
100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -883,9 +883,16 @@ static void tcp_v6_send_response(const struct sock *sk,
struct sk_buff *skb, u32
fl6.flowi6_oif = oif;
}
- if (sk)
- mark = (sk->sk_state == TCP_TIME_WAIT) ?
- inet_twsk(sk)->tw_mark : sk->sk_mark;
+ if (sk) {
+ if (sk->sk_state == TCP_TIME_WAIT) {
+ mark = inet_twsk(sk)->tw_mark;
+ /* autoflowlabel relies on buff->hash */
+ skb_set_hash(buff, inet_twsk(sk)->tw_txhash,
+ PKT_HASH_TYPE_L4);
+ } else {
+ mark = sk->sk_mark;
+ }
+ }
fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark) ?: mark;
fl6.fl6_dport = t1->dest;
fl6.fl6_sport = t1->source;
--
2.22.0.rc2.383.gf4fbbf30c2-goog
