[PATCH] net: enetc: Fix use after free issue in fsl_enetc.c

[Simon Glass]

On Wed, 31 Aug 2022 at 05:20, Siarhei Yasinski
<siarhei.yasinski at sintecs.eu> wrote:
>
> If ethernet connected to SFP, like this:
>
> &enetc_port0 {
>             phy-connection-type = "sgmii";
>             sfp = <&sfp0>;
>             managed = "in-band-status";
>             status = "okay";
> };
>
> Then enetc_config_phy returns -ENODEV and the memory containing the mdio interface is freed.
> It's better to unregister and free mdio resources.
>
> Signed-off-by: Siarhei Yasinski <siarhei.yasinski at sintecs.eu>

Reviewed-by: Simon Glass <sjg at chromium.org>

but note we normally use the var name 'ret' with driver model.


>
> diff --git a/drivers/net/fsl_enetc.c b/drivers/net/fsl_enetc.c
> index cd4c2c29a6..835e5bd8bd 100644
> --- a/drivers/net/fsl_enetc.c
> +++ b/drivers/net/fsl_enetc.c
> @@ -22,6 +22,8 @@
>
>  #define ENETC_DRIVER_NAME      "enetc_eth"
>
> +static int enetc_remove(struct udevice *dev);
> +
>  /*
>   * sets the MAC address in IERB registers, this setting is persistent and
>   * carried over to Linux.
> @@ -319,6 +321,7 @@ static int enetc_config_phy(struct udevice *dev)
>  static int enetc_probe(struct udevice *dev)
>  {
>         struct enetc_priv *priv = dev_get_priv(dev);
> +       int res;
>
>         if (ofnode_valid(dev_ofnode(dev)) && !ofnode_is_available(dev_ofnode(dev))) {
>                 enetc_dbg(dev, "interface disabled\n");
> @@ -350,7 +353,10 @@ static int enetc_probe(struct udevice *dev)
>
>         enetc_start_pcs(dev);
>
> -       return enetc_config_phy(dev);
> +       res = enetc_config_phy(dev);
> +       if(res)
> +               enetc_remove(dev);
> +       return res;
>  }
>
>  /*