From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: sock_copy() fixes
Date: Thu, 16 Jul 2009 18:09:55 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 16 Jul 2009 11:13:10 +0200

> [PATCH] net: sock_copy() fixes
> 
> Commit e912b1142be8f1e2c71c71001dc992c6e5eb2ec1
> (net: sk_prot_alloc() should not blindly overwrite memory)
> took care of not zeroing whole new socket at allocation time.
> 
> sock_copy() is another spot where we should be very careful.
> We should not set refcnt to a non null value, until
> we are sure other fields are correctly setup, or
> a lockless reader could catch this socket by mistake,
> while not fully (re)initialized.
> 
> This patch puts sk_node & sk_refcnt to the very beginning
> of struct sock to ease sock_copy() & sk_prot_alloc() job.
> 
> We add appropriate smp_wmb() before sk_refcnt initializations
> to match our RCU requirements (changes to sock keys should
> be committed to memory before sk_refcnt setting)
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

Applied and queued for -stable, thanks!