netfilter: Fix memory leak in nf_register_net_hook

In the rare case that when it is a attempted to use a per network device
netfilter hook and the network device does not exist the newly allocated
structure can leak.

Be a good citizen and free the newly allocated structure in the error
handling code.

Fixes: 085db2c04557 ("netfilter: Per network namespace netfilter hooks.")
Reported-by: kbuild@01.org
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 6896cee8b7334b64cb2295d81f41386ed5e85a64..87d237d20870ffa9d83e9f90c303abf61e813c35 100644 (file)
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -96,8 +96,10 @@ int nf_register_net_hook(struct net *net, const struct nf_hook_ops *reg)
        new->priority = reg->priority;
 
        nf_hook_list = find_nf_hook_list(net, reg);
-       if (!nf_hook_list)
+       if (!nf_hook_list) {
+               kfree(new);
                return -ENOENT;
+       }
 
        mutex_lock(&nf_hook_mutex);
        list_for_each_entry(elem, nf_hook_list, list) {