linux-kernel - Re: [PATCH] test_hexdump: Replace strncpy with memcpy

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Message-ID: <CAHp75VfvuMgH40Fq0A94gZGF5buf5yDKUEckMhnSnbvyb4S5xw@mail.gmail.com>
Date:   Thu, 5 Jul 2018 00:23:26 +0300
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Guenter Roeck <linux@...ck-us.net>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] test_hexdump: Replace strncpy with memcpy

On Sun, Jul 1, 2018 at 11:57 PM, Guenter Roeck <linux@...ck-us.net> wrote:
> gcc 8.1.0 complains:
>
> lib/test_hexdump.c:84:3: warning:
>         'strncpy' output truncated before terminating
>         nul copying as many bytes from a string as its length
> lib/test_hexdump.c:82:19: note: length computed here
>
> Using strncpy() is indeed less than perfect since the length of data to
> be copied has already been determined with strlen(). Replace strncpy()
> with memcpy() to address the warning and optimize the code a little.
>

If it helps for some reason I'm not objecting to switch to memcpy().

Acked-by: Andy Shevchenko <andy.shevchenko@...il.com>

> Signed-off-by: Guenter Roeck <linux@...ck-us.net>
> ---
>  lib/test_hexdump.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/test_hexdump.c b/lib/test_hexdump.c
> index 3f415d8101f3..1c3c513add77 100644
> --- a/lib/test_hexdump.c
> +++ b/lib/test_hexdump.c
> @@ -81,7 +81,7 @@ static void __init test_hexdump_prepare_test(size_t len, int rowsize,
>                 const char *q = *result++;
>                 size_t amount = strlen(q);
>
> -               strncpy(p, q, amount);
> +               memcpy(p, q, amount);
>                 p += amount;
>
>                 *p++ = ' ';
> --
> 2.7.4
>



-- 
With Best Regards,
Andy Shevchenko