diff options
| author | Daniel Lezcano <daniel.lezcano@free.fr> | 2010-05-19 10:12:19 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-05-23 23:24:36 -0700 |
| commit | 8ce6cebc2f126f3ecf2d80746ea54245adf18057 (patch) | |
| tree | 6efcd84b0a8d00aede2c52944bc8eaecc02e67de | |
| parent | a4ed89cb92f93d406ac45fe5507228a2475e32ba (diff) | |
net-2.6 : V2 - fix dev_get_valid_name
the commit:
commit d90310243fd750240755e217c5faa13e24f41536
Author: Octavian Purdila <opurdila@ixiacom.com>
Date: Wed Nov 18 02:36:59 2009 +0000
net: device name allocation cleanups
introduced a bug when there is a hash collision making impossible
to rename a device with eth%d. This bug is very hard to reproduce
and appears rarely.
The problem is coming from we don't pass a temporary buffer to
__dev_alloc_name but 'dev->name' which is modified by the function.
A detailed explanation is here:
http://marc.info/?l=linux-netdev&m=127417784011987&w=2
Changelog:
V2 : replaced strings comparison by pointers comparison
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Reviewed-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/dev.c | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 0aab66d68b1..07a48e2bf7d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -954,18 +954,22 @@ int dev_alloc_name(struct net_device *dev, const char *name) } EXPORT_SYMBOL(dev_alloc_name); -static int dev_get_valid_name(struct net *net, const char *name, char *buf, - bool fmt) +static int dev_get_valid_name(struct net_device *dev, const char *name, bool fmt) { + struct net *net; + + BUG_ON(!dev_net(dev)); + net = dev_net(dev); + if (!dev_valid_name(name)) return -EINVAL; if (fmt && strchr(name, '%')) - return __dev_alloc_name(net, name, buf); + return dev_alloc_name(dev, name); else if (__dev_get_by_name(net, name)) return -EEXIST; - else if (buf != name) - strlcpy(buf, name, IFNAMSIZ); + else if (dev->name != name) + strlcpy(dev->name, name, IFNAMSIZ); return 0; } @@ -997,7 +1001,7 @@ int dev_change_name(struct net_device *dev, const char *newname) memcpy(oldname, dev->name, IFNAMSIZ); - err = dev_get_valid_name(net, newname, dev->name, 1); + err = dev_get_valid_name(dev, newname, 1); if (err < 0) return err; @@ -4965,7 +4969,7 @@ int register_netdevice(struct net_device *dev) } } - ret = dev_get_valid_name(net, dev->name, dev->name, 0); + ret = dev_get_valid_name(dev, dev->name, 0); if (ret) goto err_uninit; @@ -5574,7 +5578,7 @@ 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(net, pat, dev->name, 1)) + if (dev_get_valid_name(dev, pat, 1)) goto out; } |