Patchwork [2/2] netfilter: nf_conntrack_ipv6: Plug sk_buff leak in fragment handling

mail settings
Submitter Pablo Neira
Date June 21, 2013, 12:38 a.m.
Message ID <>
Download mbox | patch
Permalink /patch/253110/
State Superseded
Headers show


Pablo Neira - June 21, 2013, 12:38 a.m.
From: Phil Oester <>

In commit 4cdd3408 ("netfilter: nf_conntrack_ipv6: improve fragmentation
handling"), an sk_buff leak was introduced when dealing with reassembled
packets by grabbing a reference to the original skb instead of the
reassembled skb.  At this point, the leak only impacted conntracks with an
associated helper.

In commit 58a317f1 ("netfilter: ipv6: add IPv6 NAT support"), the bug was
expanded to include all reassembled packets with unconfirmed conntracks.

Fix this by grabbing a reference to the proper reassembled skb.  This
closes netfilter bugzilla #823.

Signed-off-by: Phil Oester <>
Signed-off-by: Pablo Neira Ayuso <>
 net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)


diff --git a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
index 97bcf2b..c9b6a6e 100644
--- a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
@@ -204,7 +204,7 @@  static unsigned int __ipv6_conntrack_in(struct net *net,
 		if (ct != NULL && !nf_ct_is_untracked(ct)) {
 			help = nfct_help(ct);
 			if ((help && help->helper) || !nf_ct_is_confirmed(ct)) {
-				nf_conntrack_get_reasm(skb);
+				nf_conntrack_get_reasm(reasm);
 				NF_HOOK_THRESH(NFPROTO_IPV6, hooknum, reasm,
 					       (struct net_device *)in,
 					       (struct net_device *)out,