From 828de4f6bf6e785f7b5497f8f7cfd4d4fbcfdb7e Mon Sep 17 00:00:00 2001 From: Gao feng Date: Thu, 13 Sep 2012 20:58:27 +0000 Subject: [PATCH] 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: Gao feng Signed-off-by: David S. Miller --- net/core/dev.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 52cd1d7f004a..bb42eb161969 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -959,18 +959,30 @@ int dev_alloc_name(struct net_device *dev, const char *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)); - net = dev_net(dev); + ret = __dev_alloc_name(net, name, buf); + 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)) return -EINVAL; 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)) return -EEXIST; 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); - err = dev_get_valid_name(dev, newname); + err = dev_get_valid_name(net, dev, newname); if (err < 0) return err; @@ -5589,7 +5601,7 @@ int register_netdevice(struct net_device *dev) dev->iflink = -1; - ret = dev_get_valid_name(dev, dev->name); + ret = dev_get_valid_name(net, dev, dev->name); if (ret < 0) 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 */ if (!pat) goto out; - if (dev_get_valid_name(dev, pat) < 0) + if (dev_get_valid_name(net, dev, pat) < 0) goto out; } -- 2.39.2