From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Graf <tgraf@suug.ch>
Subject: Re: [PATCH 2/7] sock_diag: Do not use RTA_PUT() macros
Date: Wed, 27 Jun 2012 06:07:43 -0400
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Cc: davem@davemloft.net, netdev@vger.kernel.org
To: David Laight <David.Laight@ACULAB.COM>
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On Wed, Jun 27, 2012 at 11:00:30AM +0100, David Laight wrote:
>  
> > @@ -35,9 +34,7 @@ EXPORT_SYMBOL_GPL(sock_diag_save_cookie);
> >  
> >  int sock_diag_put_meminfo(struct sock *sk, struct sk_buff 
> > *skb, int attrtype)
> >  {
> > -	__u32 *mem;
> > -
> > -	mem = RTA_DATA(__RTA_PUT(skb, attrtype, SK_MEMINFO_VARS *
> sizeof(__u32)));
> > +	u32 mem[SK_MEMINFO_VARS];
> 
> Isn't that likely to blow the kernel stack?

SK_MEMINFO_VARS = 8, so no. I can change it to use nla_reserve()
if wasting 32 bytes on the stack is an issue.