Commit 7797b93b authored by Toshiaki Makita's avatar Toshiaki Makita Committed by David S. Miller
Browse files

veth: Free queues on link delete 



David Ahern reported memory leak in veth.

=======================================================================
$ cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff8800354d5c00 (size 1024):
  comm "ip", pid 836, jiffies 4294722952 (age 25.904s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<(____ptrval____)>] kmemleak_alloc+0x70/0x94
    [<(____ptrval____)>] slab_post_alloc_hook+0x42/0x52
    [<(____ptrval____)>] __kmalloc+0x101/0x142
    [<(____ptrval____)>] kmalloc_array.constprop.20+0x1e/0x26 [veth]
    [<(____ptrval____)>] veth_newlink+0x147/0x3ac [veth]
    ...
unreferenced object 0xffff88002e009c00 (size 1024):
  comm "ip", pid 836, jiffies 4294722958 (age 25.898s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<(____ptrval____)>] kmemleak_alloc+0x70/0x94
    [<(____ptrval____)>] slab_post_alloc_hook+0x42/0x52
    [<(____ptrval____)>] __kmalloc+0x101/0x142
    [<(____ptrval____)>] kmalloc_array.constprop.20+0x1e/0x26 [veth]
    [<(____ptrval____)>] veth_newlink+0x219/0x3ac [veth]
=======================================================================

veth_rq allocated in veth_newlink() was not freed on dellink.

We need to free up them after veth_close() so that any packets will not
reference the queues afterwards. Thus free them in veth_dev_free() in
the same way as freeing stats structure (vstats).

Also move queues allocation to veth_dev_init() to be in line with stats
allocation.

Fixes: 638264dc ("veth: Support per queue XDP ring")
Reported-by: default avatarDavid Ahern <dsahern@gmail.com>
Signed-off-by: default avatarToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Reviewed-by: default avatarDavid Ahern <dsahern@gmail.com>
Tested-by: default avatarDavid Ahern <dsahern@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ff93bca7

drivers/net/veth.c

+33 −37
Original line number Diff line number Diff line
@@ -789,16 +789,48 @@ static int is_valid_veth_mtu(int mtu) 
	return mtu >= ETH_MIN_MTU && mtu <= ETH_MAX_MTU;

}



static int veth_alloc_queues(struct net_device *dev)

{

	struct veth_priv *priv = netdev_priv(dev);

	int i;



	priv->rq = kcalloc(dev->num_rx_queues, sizeof(*priv->rq), GFP_KERNEL);

	if (!priv->rq)

		return -ENOMEM;



	for (i = 0; i < dev->num_rx_queues; i++)

		priv->rq[i].dev = dev;



	return 0;

}



static void veth_free_queues(struct net_device *dev)

{

	struct veth_priv *priv = netdev_priv(dev);



	kfree(priv->rq);

}



static int veth_dev_init(struct net_device *dev)

{

	int err;



	dev->vstats = netdev_alloc_pcpu_stats(struct pcpu_vstats);

	if (!dev->vstats)

		return -ENOMEM;



	err = veth_alloc_queues(dev);

	if (err) {

		free_percpu(dev->vstats);

		return err;

	}



	return 0;

}



static void veth_dev_free(struct net_device *dev)

{

	veth_free_queues(dev);

	free_percpu(dev->vstats);

}
@@ -1040,31 +1072,13 @@ static int veth_validate(struct nlattr *tb[], struct nlattr *data[], 
	return 0;

}



static int veth_alloc_queues(struct net_device *dev)

{

	struct veth_priv *priv = netdev_priv(dev);



	priv->rq = kcalloc(dev->num_rx_queues, sizeof(*priv->rq), GFP_KERNEL);

	if (!priv->rq)

		return -ENOMEM;



	return 0;

}



static void veth_free_queues(struct net_device *dev)

{

	struct veth_priv *priv = netdev_priv(dev);



	kfree(priv->rq);

}



static struct rtnl_link_ops veth_link_ops;



static int veth_newlink(struct net *src_net, struct net_device *dev,

			struct nlattr *tb[], struct nlattr *data[],

			struct netlink_ext_ack *extack)

{

	int err, i;

	int err;

	struct net_device *peer;

	struct veth_priv *priv;

	char ifname[IFNAMSIZ];
@@ -1117,12 +1131,6 @@ static int veth_newlink(struct net *src_net, struct net_device *dev, 
		return PTR_ERR(peer);

	}



	err = veth_alloc_queues(peer);

	if (err) {

		put_net(net);

		goto err_peer_alloc_queues;

	}



	if (!ifmp || !tbp[IFLA_ADDRESS])

		eth_hw_addr_random(peer);
@@ -1151,10 +1159,6 @@ static int veth_newlink(struct net *src_net, struct net_device *dev, 
	 * should be re-allocated

	 */



	err = veth_alloc_queues(dev);

	if (err)

		goto err_alloc_queues;



	if (tb[IFLA_ADDRESS] == NULL)

		eth_hw_addr_random(dev);
@@ -1174,28 +1178,20 @@ static int veth_newlink(struct net *src_net, struct net_device *dev, 
	 */



	priv = netdev_priv(dev);

	for (i = 0; i < dev->real_num_rx_queues; i++)

		priv->rq[i].dev = dev;

	rcu_assign_pointer(priv->peer, peer);



	priv = netdev_priv(peer);

	for (i = 0; i < peer->real_num_rx_queues; i++)

		priv->rq[i].dev = peer;

	rcu_assign_pointer(priv->peer, dev);



	return 0;



err_register_dev:

	veth_free_queues(dev);

err_alloc_queues:

	/* nothing to do */

err_configure_peer:

	unregister_netdevice(peer);

	return err;



err_register_peer:

	veth_free_queues(peer);

err_peer_alloc_queues:

	free_netdev(peer);

	return err;

}

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