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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Mon, 5 Dec 2022 15:15:47 +0200
Message-ID: <CAHp75VfLGUF4vqeObEOjRKzc+R+oYgsUZSdvVd+Echnq2DNRqw@mail.gmail.com>
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 3:13 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Mon, Dec 5, 2022 at 1:42 PM <yang.yang29@zte.com.cn> wrote:

...

> >         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).

Btw, have you compiled this with `make W=1 ...`? I believe you will
get a new warning after your change.

-- 
With Best Regards,
Andy Shevchenko