Re: [PATCH v2 2/5] can: rcar_canfd: Add support for r8a779a0 SoC

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Ulrich Hecht <uli+renesas@fpond.eu>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	netdev <netdev@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	linux-can@vger.kernel.org, "Lad,
	Prabhakar" <prabhakar.mahadev-lad.rj@bp.renesas.com>,
	Biju Das <biju.das.jz@bp.renesas.com>,
	Wolfram Sang <wsa@kernel.org>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	Wolfgang Grandegger <wg@grandegger.com>,
	Jakub Kicinski <kuba@kernel.org>,
	Vincent Mailhol <mailhol.vincent@wanadoo.fr>,
	socketcan@hartkopp.net,
	Kieran Bingham <kieran.bingham@ideasonboard.com>
Subject: Re: [PATCH v2 2/5] can: rcar_canfd: Add support for r8a779a0 SoC
Date: Wed, 26 Jan 2022 13:46:48 +0100	[thread overview]
Message-ID: <CAMuHMdWhRULedk1GCav+8=DMc9OqKTtuaG1XHNqxurF9S=s18w@mail.gmail.com> (raw)
In-Reply-To: <20220112184327.f7fwzgqvle23gfzv@pengutronix.de>

Hi Marc,

On Wed, Jan 12, 2022 at 7:43 PM Marc Kleine-Budde <mkl@pengutronix.de> wrote:
> On 11.01.2022 17:22:28, Ulrich Hecht wrote:
> > Adds support for the CANFD IP variant in the V3U SoC.
> >
> > Differences to controllers in other SoCs are limited to an increase in
> > the number of channels from two to eight, an absence of dedicated
> > registers for "classic" CAN mode, and a number of differences in magic
> > numbers (register offsets and layouts).
> >
> > Inspired by BSP patch by Kazuya Mizuguchi.
> >
> > Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu>

> > --- a/drivers/net/can/rcar/rcar_canfd.c
> > +++ b/drivers/net/can/rcar/rcar_canfd.c

> > -     of_child = of_get_child_by_name(pdev->dev.of_node, "channel1");
> > -     if (of_child && of_device_is_available(of_child))
> > -             channels_mask |= BIT(1);        /* Channel 1 */
> > +     strcpy(name, "channelX");
>
> please use strlcpy()

Why? To cause a silent failure instead of a possible crash, in the unlikely
case the buffer is shrinked or the string is enlarged?

What about preinitializing it at declaration time instead:

    char name[9] = "channelX";

?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds