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Date: Wed, 25 Jul 2007 11:53:46 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Johannes Berg <johannes@sipsolutions.net>
cc: Andrew Morton <akpm@linux-foundation.org>,
       linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [RFC] fix slub krealloc()
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On Wed, 25 Jul 2007, Johannes Berg wrote:

> > 
> > There is no use of ZERO_OR_NULL ptr in krealloc. Linus added a check to
> > ksize() instead so that ksize(NULL) returns 0 instead of failing.
> 
> However, this still doesn't fix the other corner case I pointed out:
> krealloc(NULL, 0, GFP_KERNEL) will give you a NULL pointer instead of a
> ZERO_SIZE_PTR afaict.

It will give you a ZERO_SIZE_PTR

void *krealloc(const void *p, size_t new_size, gfp_t flags)
{
        void *ret;
        size_t ks;

        if (unlikely(!new_size)) {
                kfree(p);
                return ZERO_SIZE_PTR;
        }