This is a note to let you know that I've just added the patch titled

tun: call dev_get_valid_name() before register_netdevice()

to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: tun-call-dev_get_valid_name-before-register_netdevice.patch and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Thu Nov 16 15:48:06 CET 2017

From: Cong Wang xiyou.wangcong@gmail.com Date: Fri, 13 Oct 2017 11:58:53 -0700 Subject: tun: call dev_get_valid_name() before register_netdevice()

From: Cong Wang xiyou.wangcong@gmail.com

[ Upstream commit 0ad646c81b2182f7fa67ec0c8c825e0ee165696d ]

register_netdevice() could fail early when we have an invalid dev name, in which case ->ndo_uninit() is not called. For tun device, this is a problem because a timer etc. are already initialized and it expects ->ndo_uninit() to clean them up.

We could move these initializations into a ->ndo_init() so that register_netdevice() knows better, however this is still complicated due to the logic in tun_detach().

Therefore, I choose to just call dev_get_valid_name() before register_netdevice(), which is quicker and much easier to audit. And for this specific case, it is already enough.

Fixes: 96442e42429e ("tuntap: choose the txq based on rxq") Reported-by: Dmitry Alexeev avekceeb@gmail.com Cc: Jason Wang jasowang@redhat.com Cc: "Michael S. Tsirkin" mst@redhat.com Signed-off-by: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/tun.c | 3 +++ include/linux/netdevice.h | 3 +++ net/core/dev.c | 6 +++--- 3 files changed, 9 insertions(+), 3 deletions(-)

--- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1656,6 +1656,9 @@ static int tun_set_iff(struct net *net,

if (!dev) return -ENOMEM; + err = dev_get_valid_name(net, dev, name); + if (err) + goto err_free_dev;

dev_net_set(dev, net); dev->rtnl_link_ops = &tun_link_ops; --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3245,6 +3245,9 @@ struct net_device *alloc_netdev_mqs(int unsigned char name_assign_type, void (*setup)(struct net_device *), unsigned int txqs, unsigned int rxqs); +int dev_get_valid_name(struct net *net, struct net_device *dev, + const char *name); + #define alloc_netdev(sizeof_priv, name, name_assign_type, setup) \ alloc_netdev_mqs(sizeof_priv, name, name_assign_type, setup, 1, 1)

--- a/net/core/dev.c +++ b/net/core/dev.c @@ -1059,9 +1059,8 @@ static int dev_alloc_name_ns(struct net return ret; }

-static int dev_get_valid_name(struct net *net, - struct net_device *dev, - const char *name) +int dev_get_valid_name(struct net *net, struct net_device *dev, + const char *name) { BUG_ON(!net);

@@ -1077,6 +1076,7 @@ static int dev_get_valid_name(struct net

return 0; } +EXPORT_SYMBOL(dev_get_valid_name);

/** * dev_change_name - change name of a device

Patches currently in stable-queue which might be from xiyou.wangcong@gmail.com are

queue-3.18/tun-call-dev_get_valid_name-before-register_netdevice.patch queue-3.18/tun-allow-positive-return-values-on-dev_get_valid_name-call.patch