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Subject: Re: [PATCH] drivers: mtd: mtdswap: fix possible null dereference
From: Artem Bityutskiy <dedekind1@gmail.com>
To: maxin <john.maxin@nokia.com>
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Date: Fri, 20 May 2011 08:46:05 +0300
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Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>, linux-mtd@lists.infradead.org,
	David Woodhouse <dwmw2@infradead.org>
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On Wed, 2011-05-18 at 13:00 +0100, maxin wrote:
> This patch fixes the possible null dereference of the variable "oinfo"
> Thanks to Coverity for spotting this.
> 
> Signed-off-by: Maxin B. John <john.maxin@nokia.com>
> ---
> diff --git a/drivers/mtd/mtdswap.c b/drivers/mtd/mtdswap.c
> index fed215c..863987c 100644
> --- a/drivers/mtd/mtdswap.c
> +++ b/drivers/mtd/mtdswap.c
> @@ -1450,7 +1450,12 @@ static void mtdswap_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
>  	}
>  
>  	oinfo = mtd->ecclayout;
> -	if (!mtd->oobsize || !oinfo || oinfo->oobavail < MTDSWAP_OOBSIZE) {
> +	if (!oinfo) {
> +		printk(KERN_ERR "Not enough free bytes available for ECC");
> +		return;
> +	}

Does this print makes sense? Which ECC? I think it should me something
like "mtd% does not have OOB", mtd->index.

Moreover, you should make the print consistent with the other prints
which start with MTDSWAP_PREFIX.

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)