Re: Gaah: selinux_socket_unix_stream_connect oops

[David Miller <davem@davemloft.net>]

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 5 Jan 2011 15:32:44 -0800

> On Wed, Jan 5, 2011 at 2:25 PM, David Miller <davem@davemloft.net> wrote:
>>
>> More seriously, we can get at the struct socket via sk->sk_socket in
>> the SMACK code.  sk->sk_socket, unlike socket->sk, has it's state
>> change to NULL (via sock_orphen()) protected by unix_state_lock(),
>> which we hold for "other" in this unix connect code path.
>>
>> Therefore I propose we fix this like so:
> 
> Looks fine to me.
> 
> And no, I don't think that selinux is all the world, but selinux is
> the _common_ case, and with the cross-pointers, the only difference
> can be whether you need to dereference the pointer or not - so
> choosing the "extra dereference" case for the common case seems silly.
> 
> The fact that this also fixes locking is obviously an even better
> reason to do it, though ;)

Right :)

I'll toss this your way during the merge window and queue it up for
later -stable submission as well.

Thanks.