[PATCH AUTOSEL for 4.9 064/100] netfilter: nfnetlink_queue: fix secctx memory leak

From: alexander . levin
Date: Tue Dec 12 2017 - 21:33:08 EST


From: Liping Zhang <zlpnobody@xxxxxxxxx>

[ Upstream commit 77c1c03c5b8ef28e55bb0aff29b1e006037ca645 ]

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@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
net/netfilter/nfnetlink_queue.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index af832c526048..5efb40291ac3 100644
--- 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;
}

--
2.11.0