[NETFILTER]: nf_conntrack_tcp: fix connection reopening fix

If one side aborts an established connection, the entry still lingers
for 10s in conntrack for the late packets. Allow to open up the
connection again for the party which sent the RST packet.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index c7075345971b000d6396fd07b4c710fcefc22227..4dc23ab3a39f9b4753afdba3d53d33a2b975cb5e 100644 (file)
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -834,10 +834,12 @@ static int tcp_packet(struct nf_conn *conntrack,
        case TCP_CONNTRACK_SYN_SENT:
                if (old_state < TCP_CONNTRACK_TIME_WAIT)
                        break;
-               if (conntrack->proto.tcp.seen[!dir].flags &
-                       IP_CT_TCP_FLAG_CLOSE_INIT) {
-                       /* Attempt to reopen a closed connection.
-                       * Delete this connection and look up again. */
+               if ((conntrack->proto.tcp.seen[!dir].flags &
+                       IP_CT_TCP_FLAG_CLOSE_INIT)
+                   || (conntrack->proto.tcp.last_dir == dir
+                       && conntrack->proto.tcp.last_index == TCP_RST_SET)) {
+                       /* Attempt to reopen a closed/aborted connection.
+                        * Delete this connection and look up again. */
                        write_unlock_bh(&tcp_lock);
                        if (del_timer(&conntrack->timeout))
                                conntrack->timeout.function((unsigned long)
@@ -925,6 +927,7 @@ static int tcp_packet(struct nf_conn *conntrack,
      in_window:
        /* From now on we have got in-window packets */
        conntrack->proto.tcp.last_index = index;
+       conntrack->proto.tcp.last_dir = dir;
 
        pr_debug("tcp_conntracks: ");
        NF_CT_DUMP_TUPLE(tuple);