From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [BUG?] dst reference leak possible in ndisc_send
Date: Sat, 19 Jul 2008 23:33:24 -0700
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	David Miller <davem@davemloft.net>, netdev@vger.kernel.org
To: Stephen Hemminger <shemminger@vyatta.com>
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On Sat, 19 Jul 2008 23:31:40 -0700
Stephen Hemminger <shemminger@vyatta.com> wrote:

> This code path looks like it leaks the dst_entry  if xfrm_lookup fails:
> 
> static void __ndisc_send(struct net_device *dev,
> 			 struct neighbour *neigh,
> 			 const struct in6_addr *daddr,
> 			 const struct in6_addr *saddr,
> 			 struct icmp6hdr *icmp6h, const struct in6_addr *target,
> 			 int llinfo)
> {
> 	struct flowi fl;
> 	struct dst_entry *dst;
> 	struct net *net = dev_net(dev);
> 	struct sock *sk = net->ipv6.ndisc_sk;
> 	struct sk_buff *skb;
> 	struct icmp6hdr *hdr;
> 	struct inet6_dev *idev;
> 	int len;
> 	int err;
> 	u8 *opt, type;
> 
> 	type = icmp6h->icmp6_type;
> 
> 	icmpv6_flow_init(sk, &fl, type, saddr, daddr, dev->ifindex);
> 
> 	dst = icmp6_dst_alloc(dev, neigh, daddr);
> 	if (!dst)
> 		return;
> 
> 	err = xfrm_lookup(&dst, &fl, NULL, 0);
> 	if (err < 0)
> 		return;

Never mind xfrm_lookup frees dst on error