openvswitch: Fix template leak in error cases.

Commit 5b48bb8506c5 ("openvswitch: Fix helper reference leak") fixed a
reference leak on helper objects, but inadvertently introduced a leak on
the ct template.

Previously, ct_info.ct->general.use was initialized to 0 by
nf_ct_tmpl_alloc() and only incremented when ovs_ct_copy_action()
returned successful. If an error occurred while adding the helper or
adding the action to the actions buffer, the __ovs_ct_free_action()
cleanup would use nf_ct_put() to free the entry; However, this relies on
atomic_dec_and_test(ct_info.ct->general.use). This reference must be
incremented first, or nf_ct_put() will never free it.

Fix the issue by acquiring a reference to the template immediately after
allocation.

Fixes: cae3a2627520 ("openvswitch: Allow attaching helpers to ct action")
Fixes: 5b48bb8506c5 ("openvswitch: Fix helper reference leak")
Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index 3e8892216f948f54afb75fde76bf2b1fa7b754ca..e004067ec24ac448467c0bd5a552eea019975e56 100644 (file)
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -698,6 +698,10 @@ int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
                OVS_NLERR(log, "Failed to allocate conntrack template");
                return -ENOMEM;
        }
+
+       __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
+       nf_conntrack_get(&ct_info.ct->ct_general);
+
        if (helper) {
                err = ovs_ct_add_helper(&ct_info, helper, key, log);
                if (err)
@@ -709,8 +713,6 @@ int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
        if (err)
                goto err_free_ct;
 
-       __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
-       nf_conntrack_get(&ct_info.ct->ct_general);
        return 0;
 err_free_ct:
        __ovs_ct_free_action(&ct_info);