Commit 828de4f6 authored by Gao feng's avatar Gao feng Committed by David S. Miller
Browse files

net: dev: fix incorrect getting net device's name 



When moving a nic from net namespace A to net namespace B,
in dev_change_net_namesapce,we call __dev_get_by_name to
decide if the netns B has the device has the same name.

if the netns B already has the same named device,we call
dev_get_valid_name to try to get a valid name for this nic in
the netns B,but net_device->nd_net still point to netns A now.

this patch fix it.

Signed-off-by: default avatarGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3fd91fb3

net/core/dev.c

+20 −8
Original line number Original line Diff line number Diff line
@@ -959,18 +959,30 @@ int dev_alloc_name(struct net_device *dev, const char *name) 
}

}

EXPORT_SYMBOL(dev_alloc_name);

EXPORT_SYMBOL(dev_alloc_name);





static int dev_get_valid_name(struct net_device *dev, const char *name)

static int dev_alloc_name_ns(struct net *net,

			     struct net_device *dev,

			     const char *name)

{

{

	struct net *net;

	char buf[IFNAMSIZ];

	int ret;





	BUG_ON(!dev_net(dev));

	ret = __dev_alloc_name(net, name, buf);

	net = dev_net(dev);

	if (ret >= 0)

		strlcpy(dev->name, buf, IFNAMSIZ);

	return ret;

}



static int dev_get_valid_name(struct net *net,

			      struct net_device *dev,

			      const char *name)

{

	BUG_ON(!net);





	if (!dev_valid_name(name))

	if (!dev_valid_name(name))

		return -EINVAL;

		return -EINVAL;





	if (strchr(name, '%'))

	if (strchr(name, '%'))

		return dev_alloc_name(dev, name);

		return dev_alloc_name_ns(net, dev, name);

	else if (__dev_get_by_name(net, name))

	else if (__dev_get_by_name(net, name))

		return -EEXIST;

		return -EEXIST;

	else if (dev->name != name)

	else if (dev->name != name)
@@ -1006,7 +1018,7 @@ int dev_change_name(struct net_device *dev, const char *newname) 




	memcpy(oldname, dev->name, IFNAMSIZ);

	memcpy(oldname, dev->name, IFNAMSIZ);





	err = dev_get_valid_name(dev, newname);

	err = dev_get_valid_name(net, dev, newname);

	if (err < 0)

	if (err < 0)

		return err;

		return err;
@@ -5589,7 +5601,7 @@ int register_netdevice(struct net_device *dev) 




	dev->iflink = -1;

	dev->iflink = -1;





	ret = dev_get_valid_name(dev, dev->name);

	ret = dev_get_valid_name(net, dev, dev->name);

	if (ret < 0)

	if (ret < 0)

		goto out;

		goto out;
@@ -6233,7 +6245,7 @@ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char 
		/* We get here if we can't use the current device name */

		/* We get here if we can't use the current device name */

		if (!pat)

		if (!pat)

			goto out;

			goto out;

		if (dev_get_valid_name(dev, pat) < 0)

		if (dev_get_valid_name(net, dev, pat) < 0)

			goto out;

			goto out;

	}

	}

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