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Subject: Re: [PATCH] kernel: use kcalloc instead kmalloc/memset
From: Arjan van de Ven <arjan@infradead.org>
To: Roman Zippel <zippel@linux-m68k.org>
Cc: Andrew Morton <akpm@osdl.org>, Pekka J Enberg <penberg@cs.Helsinki.FI>,
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Date: Fri, 05 Aug 2005 12:38:09 +0200
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On Fri, 2005-08-05 at 12:32 +0200, Roman Zippel wrote:
> Hi,
> 
> On Fri, 5 Aug 2005, Arjan van de Ven wrote:
> 
> > > This would imply a similiar kmalloc() would be useful as well.
> > > Second, how relevant is it for the kernel? 
> > 
> > we've had a non-negliable amount of security holes because of this
> 
> So why don't we have a similiar kmalloc()?

nope kmalloc is not an array allocator
> 
> > > Is that really the best place 
> > > to check for rogue user parameters?
> > 
> > it makes it easy and safe. Of course you can and should check it in all
> > users. Just that using a safer API is generally better than forcing
> > everyone to do it themselves.
> 
> How exactly does this make it a "safe API"? Even if it checks for this one 
> case, it still makes the user suspectible for allocating big amounts of 
> unswappable memory.

128Kb max.