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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 0/6] Cleanup the kernel sockets.
Date: Mon, 11 May 2015 10:53:08 -0400 (EDT)
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From: ebiederm@xmission.com (Eric W. Biederman)
Date: Fri, 08 May 2015 21:05:33 -0500

> Right now the situtation for allocating kernel sockets is a mess.
> - sock_create_kern does not take a namespace parameter.
> - kernel sockets must not reference count a network namespace and keep
>   it alive or else we will have a reference counting loop.
> - The way we avoid the reference counting loop with sk_change_net
>   and sk_release_kernel are major hacks.
> 
> This patchset addresses this mess by fixing sock_create_kern to do
> everything necessary to create a kernel socket.  None of the current
> users of kernel sockets need the network namespace reference counted.
> Either kernel sockets are network namespace aware (and using the current
> hacks) or kernel sockets are limited to the initial network namespace
> in which case it does not matter.
> 
> This patchset starts by addressing tun which should be using normal
> userspace sockets like macvtap.
> 
> Then sock_create_kern is fixed to take a network namespace.
> Then the in kernel status of sockets are passed through to sk_alloc.
> Then sk_alloc is fixed to not reference count the network namespace
>      of kernel sockets.
> Then the callers of sock_create_kern are fixed up to stop using hacks.
> Then netlink which uses it's own flavor of sock_create_kern is fixed.
> 
> Finally the hacks that are sk_change_net and sk_release_kernel are removed.
> 
> When it is all done the code is easier to follow, easier to use, easier
> to maintain and shorter by about 70 lines.
> 
> Reported-by: Ying Xue <ying.xue@windriver.com>

Looks good, applied to net-next, thanks Eric.