netfilter: ctnetlink: fix possible refcount leak in ctnetlink_create_conntrack()

nf_ct_put() needs to be called to put the refcount got by
nf_conntrack_find_get() to avoid refcount leak when
nf_conntrack_hash_check_insert() fails.

Fixes: 7d367e06688d ("netfilter: ctnetlink: fix soft lockup when netlink adds new entries (v2)")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 1286ae7..ca4d5bb 100644 (file)
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -2375,12 +2375,15 @@ ctnetlink_create_conntrack(struct net *net,
 
        err = nf_conntrack_hash_check_insert(ct);
        if (err < 0)
-               goto err2;
+               goto err3;
 
        rcu_read_unlock();
 
        return ct;
 
+err3:
+       if (ct->master)
+               nf_ct_put(ct->master);
 err2:
        rcu_read_unlock();
 err1: