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Date:   Wed, 5 Jul 2023 11:34:20 -0700
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Subject: Re: [PATCH] ACPI: NFIT: limit string attribute write
To:     Ben Dooks <ben.dooks@codethink.co.uk>,
        <linux-kernel@vger.kernel.org>, <linux-acpi@vger.kernel.org>
CC:     <nvdimm@lists.linux.dev>, <lenb@kernel.org>
References: <20230704081751.12170-1-ben.dooks@codethink.co.uk>
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From:   Dave Jiang <dave.jiang@intel.com>
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On 7/4/23 01:17, Ben Dooks wrote:
> If we're writing what could be an arbitrary sized string into an attribute
> we should probably use snprintf() just to be safe. Most of the other
> attriubtes are some sort of integer so unlikely to be an issue so not
> altered at this time.
> 
> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
> ---
>   drivers/acpi/nfit/core.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> index 9213b426b125..d7e9d9cd16d2 100644
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -1579,7 +1579,7 @@ static ssize_t id_show(struct device *dev,
>   {
>   	struct nfit_mem *nfit_mem = to_nfit_mem(dev);
>   
> -	return sprintf(buf, "%s\n", nfit_mem->id);
> +	return snprintf(buf, PAGE_SIZE, "%s\n", nfit_mem->id);

Why not just convert it to sysfs_emit()?

>   }
>   static DEVICE_ATTR_RO(id);
>