[NETLINK]: Defer socket destruction a bit

In netlink_broadcast() we're sending shared skb's to netlink listeners
when possible (saves some copying). This is OK, since we hold the only
other reference to the skb.

However, this implies that we must drop our reference on the skb, before
allowing a receiving socket to disappear. Otherwise, the socket buffer
accounting is disrupted.

Signed-off-by: Tommy S. Christensen <tommy.christensen@tpack.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 4b91f4b84cb7..e41ce458c2a9 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -789,11 +789,12 @@ int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
         sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
                 do_one_broadcast(sk, &info);
 
+        kfree_skb(skb);
+
         netlink_unlock_table();
 
         if (info.skb2)
                 kfree_skb(info.skb2);
-        kfree_skb(skb);
 
         if (info.delivered) {
                 if (info.congested && (allocation & __GFP_WAIT))