Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <a81cb8cd088e715936895ec6bb07cfdc8fec37c1.camel@sipsolutions.net>
Subject: Re: [PATCH net-next] wifi: airo: use strscpy() to instead of
 strncpy()
From:   Johannes Berg <johannes@sipsolutions.net>
To:     yang.yang29@zte.com.cn, kvalo@kernel.org
Cc:     davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com, akpm@linux-foundation.org,
        songmuchun@bytedance.com, brauner@kernel.org,
        julia.lawall@inria.fr, gustavoars@kernel.org, jason@zx2c4.com,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, xu.panda@zte.com.cn
Date:   Tue, 17 Jan 2023 22:27:57 +0100
In-Reply-To: <202212231052044562664@zte.com.cn>
References: <202212231052044562664@zte.com.cn>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
User-Agent: Evolution 3.46.3 (3.46.3-1.fc37) 
MIME-Version: 1.0
Precedence: bulk

On Fri, 2022-12-23 at 10:52 +0800, yang.yang29@zte.com.cn wrote:
> From: Xu Panda <xu.panda@zte.com.cn>
>=20
> The implementation of strscpy() is more robust and safer.
> That's now the recommended way to copy NUL-terminated strings.
>=20
> Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
> Signed-off-by: Yang Yang <yang.yang29@zte.com>
> ---
>  drivers/net/wireless/cisco/airo.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>=20
> diff --git a/drivers/net/wireless/cisco/airo.c b/drivers/net/wireless/cis=
co/airo.c
> index 7c4cc5f5e1eb..600a64f671ce 100644
> --- a/drivers/net/wireless/cisco/airo.c
> +++ b/drivers/net/wireless/cisco/airo.c
> @@ -6067,8 +6067,7 @@ static int airo_get_nick(struct net_device *dev,
>  	struct airo_info *local =3D dev->ml_priv;
>=20
>  	readConfigRid(local, 1);
> -	strncpy(extra, local->config.nodeName, 16);
> -	extra[16] =3D '\0';
> +	strscpy(extra, local->config.nodeName, 17);
>  	dwrq->length =3D strlen(extra);
>=20

Again, why bother. But is this even correct/identical behaviour?
Wouldn't it potentially read 17 input bytes before forcing NUL-
termination?

johannes