Commit 4ece9009 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

sit: fix sit0 percpu double allocations 



sit0 device allocates its percpu storage twice :
- One time in ipip6_tunnel_init()
- One time in ipip6_fb_tunnel_init()

Thus we leak 48 bytes per possible cpu per network namespace dismantle.

ipip6_fb_tunnel_init() can be much simpler and does not
return an error, and should be called after register_netdev()

Note that ipip6_tunnel_clone_6rd() also needs to be called
after register_netdev() (calling ipip6_tunnel_init())

Fixes: ebe084aa ("sit: Use ipip6_tunnel_init as the ndo_init function.")
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8fa677d2

net/ipv6/sit.c

+4 −22
Original line number Diff line number Diff line
@@ -1394,34 +1394,20 @@ static int ipip6_tunnel_init(struct net_device *dev) 
	return 0;

}



static int __net_init ipip6_fb_tunnel_init(struct net_device *dev)

static void __net_init ipip6_fb_tunnel_init(struct net_device *dev)

{

	struct ip_tunnel *tunnel = netdev_priv(dev);

	struct iphdr *iph = &tunnel->parms.iph;

	struct net *net = dev_net(dev);

	struct sit_net *sitn = net_generic(net, sit_net_id);



	tunnel->dev = dev;

	tunnel->net = dev_net(dev);



	iph->version		= 4;

	iph->protocol		= IPPROTO_IPV6;

	iph->ihl		= 5;

	iph->ttl		= 64;



	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);

	if (!dev->tstats)

		return -ENOMEM;



	tunnel->dst_cache = alloc_percpu(struct ip_tunnel_dst);

	if (!tunnel->dst_cache) {

		free_percpu(dev->tstats);

		return -ENOMEM;

	}



	dev_hold(dev);

	rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);

	return 0;

}



static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[])
@@ -1831,23 +1817,19 @@ static int __net_init sit_init_net(struct net *net) 
	 */

	sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;



	err = ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);

	if (err)

		goto err_dev_free;



	ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);

	err = register_netdev(sitn->fb_tunnel_dev);

	if (err)

		goto err_reg_dev;



	ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);

	ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);



	t = netdev_priv(sitn->fb_tunnel_dev);



	strcpy(t->parms.name, sitn->fb_tunnel_dev->name);

	return 0;



err_reg_dev:

	dev_put(sitn->fb_tunnel_dev);

err_dev_free:

	ipip6_dev_free(sitn->fb_tunnel_dev);

err_alloc_dev:

	return err;

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