Date:   Mon, 13 Mar 2023 19:59:27 +0100
From:   Simon Horman <simon.horman@corigine.com>
To:     Danila Chernetsov <listdansp@mail.ru>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org
Subject: Re: [PATCH] net: dsa: vsc73xxx: Fix uninitalized 'val' in
 vsc73xx_adjust_link
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On Sun, Mar 12, 2023 at 03:50:08PM +0000, Danila Chernetsov wrote:
> Using uninitialized variable after calls vsc73xx_read 
> without error checking may cause incorrect driver behavior.

I wonder if it is:
a) intentional that these calls are not checked for errors
b) errors can occur in these call paths

> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Fixes: 95711cd5f0b4 ("net: dsa: vsc73xx: Split vsc73xx driver")
> Signed-off-by: Danila Chernetsov <listdansp@mail.ru>
> ---
>  drivers/net/dsa/vitesse-vsc73xx-core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/dsa/vitesse-vsc73xx-core.c b/drivers/net/dsa/vitesse-vsc73xx-core.c
> index ae55167ce0a6..729005d6cb7e 100644
> --- a/drivers/net/dsa/vitesse-vsc73xx-core.c
> +++ b/drivers/net/dsa/vitesse-vsc73xx-core.c
> @@ -758,7 +758,7 @@ static void vsc73xx_adjust_link(struct dsa_switch *ds, int port,
>  				struct phy_device *phydev)
>  {
>  	struct vsc73xx *vsc = ds->priv;
> -	u32 val;
> +	u32 val = 0;
>  
>  	/* Special handling of the CPU-facing port */
>  	if (port == CPU_PORT) {
> -- 
> 2.25.1
>