Commit bcb74e13 authored by Marcelo Ricardo Leitner's avatar Marcelo Ricardo Leitner Committed by David S. Miller
Browse files

net/sched: act_ct: fix ref leak when switching zones 



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: default avatarFlorian Westphal <fw@strlen.de>
Fixes: 2f131de3 ("net/sched: act_ct: Fix flow table lookup after ct clear or switching zones")
Signed-off-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5ae6acf1

net/sched/act_ct.c

+9 −6
Original line number Diff line number Diff line
@@ -666,24 +666,27 @@ 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);



		goto drop_ct;

	}



	return true;



drop_ct:

	nf_ct_put(ct);

	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);



	return false;

}



	return true;

}



/* Trim the skb to the length specified by the IP/IPv6 header,

 * removing any trailing lower-layer padding. This prepares the skb

 * for higher-layer processing that assumes skb->len excludes padding