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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Mon, 5 Dec 2022 15:13:24 +0200
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Subject: Re: [PATCH linux-next v2] x86/platform/uv: use strscpy to instead of strncpy()
To:     yang.yang29@zte.com.cn
Cc:     steve.wahl@hpe.com, mike.travis@hpe.com, dimitri.sivanich@hpe.com,
        russ.anderson@hpe.com, dvhart@infradead.org, andy@infradead.org,
        tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
        dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
        platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org,
        xu.panda@zte.com.cn
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On Mon, Dec 5, 2022 at 1:42 PM <yang.yang29@zte.com.cn> wrote:
>
> From: Xu Panda <xu.panda@zte.com.cn>

Thank you for an update, my comments below.

> The implementation of strscpy() is more robust and safer.
> That's now the recommended way to copy NUL terminated strings.
> ---
> change for v2
>  - fix the mistake and make the code better and simpler,
> thanks to Andy Shevchenko.
> ---

This is (the changelog) in the wrong place.

> Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
> Signed-off-by: Yang Yang <yang.yang29@zte.com>

> Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>

No, I haven't given you this tag, sorry. The changelog is enough to give credit.

...

>         char arg[ACTION_LEN], *p;
>
>         /* (remove possible '\n') */
> -       strncpy(arg, val, ACTION_LEN - 1);
> -       arg[ACTION_LEN - 1] = '\0';
> -       p = strchr(arg, '\n');
> -       if (p)
> -               *p = '\0';
> +       strscpy(arg, val, strnchrnul(val, ACTION_LEN, '\n') - val);

And even better is to replace ACTION_LEN by sizeof(arg).

-- 
With Best Regards,
Andy Shevchenko