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From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
To: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] nvmem: core: fix error path in nvmem_add_cells()
Organization: D03
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	<56C45016.2010806@linaro.org>
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Date: Thu, 18 Feb 2016 06:35:46 +0100
In-Reply-To: <56C45016.2010806@linaro.org> (Srinivas Kandagatla's message of
	"Wed, 17 Feb 2016 10:48:54 +0000")
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On Wed, Feb 17 2016, Srinivas Kandagatla <srinivas.kandagatla@linaro.org> wrote:

>>   err:
>> -	while (--i)
>> +	while (i--)
>>   		nvmem_cell_drop(cells[i]);
> No, this will not work.
>
> 3 issues,
>
> 1> If we enter this err path from nvmem_cell_info_to_nvmem_cell()
> failures, you would be accessing already freed cells[i].
>
> 2> accessing un-allocated cells[i].
>
> 3> you would be trying to drop cells which are not in the list.
>
>
> This is what you need here to fix it correctly.
>
> while (--i >= 0)
>

Sigh. http://thread.gmane.org/gmane.linux.kernel.mm/146058/focus=2149595

TL;DR: They're equivalent.

Rasmus