netfilter: nfnetlink_queue: fix secctx memory leak

We must call security_release_secctx to free the memory returned by
security_secid_to_secctx, otherwise memory may be leaked forever.

Fixes: ef493bd930ae ("netfilter: nfnetlink_queue: add security context information")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 3ee0b8a000a41ec901faeb239e752a126428dc4d..933509ebf3d3e2e84aecd55fd7f19f21f69e46d4 100644 (file)
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -443,7 +443,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
        skb = alloc_skb(size, GFP_ATOMIC);
        if (!skb) {
                skb_tx_error(entskb);
-               return NULL;
+               goto nlmsg_failure;
        }
 
        nlh = nlmsg_put(skb, 0, 0,
@@ -452,7 +452,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
        if (!nlh) {
                skb_tx_error(entskb);
                kfree_skb(skb);
-               return NULL;
+               goto nlmsg_failure;
        }
        nfmsg = nlmsg_data(nlh);
        nfmsg->nfgen_family = entry->state.pf;
@@ -598,12 +598,17 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
        }
 
        nlh->nlmsg_len = skb->len;
+       if (seclen)
+               security_release_secctx(secdata, seclen);
        return skb;
 
 nla_put_failure:
        skb_tx_error(entskb);
        kfree_skb(skb);
        net_err_ratelimited("nf_queue: error creating packet message\n");
+nlmsg_failure:
+       if (seclen)
+               security_release_secctx(secdata, seclen);
        return NULL;
 }