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Date: Mon, 27 Aug 2007 00:10:17 +0200
From: "Jesper Juhl" <jesper.juhl@gmail.com>
To: "Jan Engelhardt" <jengelh@computergmbh.de>
Subject: Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in
	drivers/mtd/maps/pmcmsp-flash.c
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Cc: Denys Vlasenko <vda.linux@googlemail.com>,
	David Woodhouse <dwmw2@infradead.org>, linux-mtd@lists.infradead.org,
	"Robert P. J. Day" <rpjday@mindspring.com>,
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On 26/08/07, Jan Engelhardt <jengelh@computergmbh.de> wrote:
>
> On Aug 26 2007 15:28, Denys Vlasenko wrote:
> >> >
> >> > What exactely would using kcalloc() over kzalloc() here buy us?
> >>
> >> technically, nothing.
> >
> >The idea of calloc is that it can check for underflow in parameter.
>
> Actually, overflow.
>
> calloc(0xFFFF0000,  0x1000) => will return NULL
> malloc(0xFFFF0000 * 0x1000) => silent 32 bit multiplication/truncation,
> will allocate less than requested.
>
> >calloc(-1, 10000000) => easy to detect
> >malloc(-1 * 10000000) => malloc(-10000000) => not so trivial
>
Ok, that makes a bit of sense. Thank you.


-- 
Jesper Juhl <jesper.juhl@gmail.com>
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