[NETFILTER] ctnetlink: propagate error instaed of returning -EPERM

Propagate the error to userspace instead of returning -EPERM if the get
conntrack operation fails.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/netfilter/ip_conntrack_netlink.c

@@ -802,7 +802,7 @@ ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 free:
 	kfree_skb(skb2);
 out:
-	return -1;
+	return err;
 }
 
 static inline int