This is a note to let you know that I've just added the patch titled
net/sched: act_ct: fix ref leak when switching zones
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-sched-act_ct-fix-ref-leak-when-switching-zones.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 4d8c80508bdec217ceda6d7169997145ea3bdb89
Author: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>
Date: Thu Mar 24 16:22:10 2022 -0300
net/sched: act_ct: fix ref leak when switching zones
[ Upstream commit bcb74e132a76ce0502bb33d5b65533a4ed72d159 ]
When switching zones or network namespaces without doing a ct clear in
between, it is now leaking a reference to the old ct entry. That's
because tcf_ct_skb_nfct_cached() returns false and
tcf_ct_flow_table_lookup() may simply overwrite it.
The fix is to, as the ct entry is not reusable, free it already at
tcf_ct_skb_nfct_cached().
Reported-by: Florian Westphal <fw@xxxxxxxxx>
Fixes: 2f131de361f6 ("net/sched: act_ct: Fix flow table lookup after ct clear or switching zones")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c
index 240b3c5d2eb1..553bf41671a6 100644
--- a/net/sched/act_ct.c
+++ b/net/sched/act_ct.c
@@ -583,22 +583,25 @@ static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
if (!ct)
return false;
if (!net_eq(net, read_pnet(&ct->ct_net)))
- return false;
+ goto drop_ct;
if (nf_ct_zone(ct)->id != zone_id)
- return false;
+ goto drop_ct;
/* Force conntrack entry direction. */
if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
if (nf_ct_is_confirmed(ct))
nf_ct_kill(ct);
- nf_ct_put(ct);
- nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
-
- return false;
+ goto drop_ct;
}
return true;
+
+drop_ct:
+ nf_ct_put(ct);
+ nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
+
+ return false;
}
/* Trim the skb to the length specified by the IP/IPv6 header,
