linux-kernel - Re: kmalloc() with size zero

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Date:	Fri, 23 Mar 2007 08:12:39 -0700 (PDT)
From:	Christoph Lameter <clameter@....com>
To:	Stephane Eranian <eranian@....hp.com>
cc:	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org, ak@...e.de
Subject: Re: kmalloc() with size zero

On Thu, 22 Mar 2007, Stephane Eranian wrote:

> I ran into an issue with perfmon where I ended up calling
> kmalloc() with a size of zero. To my surprise, this did
> not return NULL but a valid data address.
> 
> I am wondering if this is a property of kmalloc() or simply
> a bug. It is the case that the __kmalloc() code does not
> check for zero size.

Correct SLAB will give you the smallest possible allocation. I'd say these 
calls should be fixed. SLUB does check for zero and will throw a stack 
dump.

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