[PATCH 4.4 051/312] netfilter: nfnetlink: use original skbuff when acking batches

[Greg Kroah-Hartman]

From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

commit 7c7bdf35991bb8f7cfaeaf22ea3a2f2d1967c166 upstream.

Since bd678e09dc17 ("netfilter: nfnetlink: fix splat due to incorrect
socket memory accounting in skbuff clones"), we don't manually attach
the sk to the skbuff clone anymore, so we have to use the original
skbuff from netlink_ack() which needs to access the sk pointer.

Fixes: bd678e09dc17 ("netfilter: nfnetlink: fix splat due to incorrect socket memory accounting in skbuff clones")
Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/netfilter/nfnetlink.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -309,14 +309,14 @@ replay:
 #endif
 		{
 			nfnl_unlock(subsys_id);
-			netlink_ack(skb, nlh, -EOPNOTSUPP);
+			netlink_ack(oskb, nlh, -EOPNOTSUPP);
 			return kfree_skb(skb);
 		}
 	}
 
 	if (!ss->commit || !ss->abort) {
 		nfnl_unlock(subsys_id);
-		netlink_ack(skb, nlh, -EOPNOTSUPP);
+		netlink_ack(oskb, nlh, -EOPNOTSUPP);
 		return kfree_skb(skb);
 	}
 
@@ -406,7 +406,7 @@ ack:
 				 * pointing to the batch header.
 				 */
 				nfnl_err_reset(&err_list);
-				netlink_ack(skb, nlmsg_hdr(oskb), -ENOMEM);
+				netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM);
 				status |= NFNL_BATCH_FAILURE;
 				goto done;
 			}