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Subject: Re: [PATCH] uacce: use sysfs_emit instead of sprintf
To:     Greg KH <gregkh@linuxfoundation.org>
References: <1621247137-42693-1-git-send-email-yekai13@huawei.com>
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        <linux-kernel@vger.kernel.org>, <linuxarm@huawei.com>,
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From:   "yekai(A)" <yekai13@huawei.com>
Message-ID: <e5290000-5481-c662-974f-85eea7660953@huawei.com>
Date:   Mon, 17 May 2021 19:49:37 +0800
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On 2021/5/17 18:36, Greg KH wrote:
> On Mon, May 17, 2021 at 06:25:37PM +0800, Kai Ye wrote:
>> Use the sysfs_emit to replace sprintf.
>
> That says _what_ you did, not _why_ you are doing this.  What problem
> are you solving with this change?
>
> thanks,
>
> greg k-h
> .
>
sprintf is not safe, and it not recommended to use.
sprintf does not know the PAGE_SIZE maximum of the temporary buffer
used for outputting sysfs content and it's possible to overrun the
PAGE_SIZE buffer length. so used sysfs_emit that  knows that the size
of the call situations that also ensures that no overrun is done. so use 
sysfs_emit to replace sprintf maybe better.

thanks,
Kai Ye