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Date:   Wed, 6 Feb 2019 10:18:44 +0100
From:   Maxime Ripard <maxime.ripard@bootlin.com>
To:     Yizhuo <yzhai003@ucr.edu>
Cc:     csong@cs.ucr.edu, zhiyunq@cs.ucr.edu,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@st.com>,
        Chen-Yu Tsai <wens@csie.org>, netdev@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: stmmac: Variable "val" in function
 sun8i_dwmac_set_syscon() could be uninitialized
Message-ID: <20190206091844.gqwomr4j2pe3vvvn@flea>
References: <20190205221559.17545-1-yzhai003@ucr.edu>
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Hi,

On Tue, Feb 05, 2019 at 02:15:59PM -0800, Yizhuo wrote:
> In function sun8i_dwmac_set_syscon(), local variable "val" could
> be uninitialized if function regmap_read() returns -EINVAL.
> However, it will be used directly in the if statement, which
> is potentially unsafe.
>=20
> Signed-off-by: Yizhuo <yzhai003@ucr.edu>
> ---
>  drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>=20
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c b/drivers/=
net/ethernet/stmicro/stmmac/dwmac-sun8i.c
> index 39c2122a4f26..11d481c9e7ab 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
> @@ -639,9 +639,14 @@ static int sun8i_dwmac_set_syscon(struct stmmac_priv=
 *priv)
>  	struct sunxi_priv_data *gmac =3D priv->plat->bsp_priv;
>  	struct device_node *node =3D priv->device->of_node;
>  	int ret;
> -	u32 reg, val;
> +	u32 reg, val =3D 0;

I guess we don't need to initialize it anymore with the check you add?

Maxime

--=20
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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