[PATCH 5.16 077/164] net/sched: act_ct: Fix flow table lookup after ct clear or switching zones

From: Greg Kroah-Hartman
Date: Mon Feb 28 2022 - 13:06:04 EST


From: Paul Blakey <paulb@xxxxxxxxxx>

commit 2f131de361f6d0eaff17db26efdb844c178432f8 upstream.

Flow table lookup is skipped if packet either went through ct clear
action (which set the IP_CT_UNTRACKED flag on the packet), or while
switching zones and there is already a connection associated with
the packet. This will result in no SW offload of the connection,
and the and connection not being removed from flow table with
TCP teardown (fin/rst packet).

To fix the above, remove these unneccary checks in flow
table lookup.

Fixes: 46475bb20f4b ("net/sched: act_ct: Software offload of established flows")
Signed-off-by: Paul Blakey <paulb@xxxxxxxxxx>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/sched/act_ct.c | 5 -----
1 file changed, 5 deletions(-)

--- a/net/sched/act_ct.c
+++ b/net/sched/act_ct.c
@@ -516,11 +516,6 @@ static bool tcf_ct_flow_table_lookup(str
struct nf_conn *ct;
u8 dir;

- /* Previously seen or loopback */
- ct = nf_ct_get(skb, &ctinfo);
- if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
- return false;
-
switch (family) {
case NFPROTO_IPV4:
if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))