[next] net: usb: asix: ax88772: Fix less than zero comparison of a u16

From: Colin Ian King <colin.king@canonical.com>

The comparison of the u16 priv->phy_addr < 0 is always false because
phy_addr is unsigned. Fix this by assigning the return from the call
to function asix_read_phy_addr to int ret and using this for the
less than zero error check comparison.

Addresses-Coverity: ("Unsigned compared against 0")
Fixes: e532a096be0e ("net: usb: asix: ax88772: add phylib support")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/net/usb/asix_devices.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

On 08/06/2021 15:58, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> The comparison of the u16 priv->phy_addr < 0 is always false because
> phy_addr is unsigned. Fix this by assigning the return from the call
> to function asix_read_phy_addr to int ret and using this for the
> less than zero error check comparison.
> 
> Addresses-Coverity: ("Unsigned compared against 0")
> Fixes: e532a096be0e ("net: usb: asix: ax88772: add phylib support")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
>  drivers/net/usb/asix_devices.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
> index 57dafb3262d9..211c5a87eb15 100644
> --- a/drivers/net/usb/asix_devices.c
> +++ b/drivers/net/usb/asix_devices.c
> @@ -704,9 +704,10 @@ static int ax88772_init_phy(struct usbnet *dev)
>  	struct asix_common_private *priv = dev->driver_priv;
>  	int ret;
>  
> -	priv->phy_addr = asix_read_phy_addr(dev, true);
> -	if (priv->phy_addr < 0)
> +	ret = asix_read_phy_addr(dev, true);
> +	if (ret < 0)
>  		return priv->phy_addr;
> +	priv->phy_addr = ret;
>  
>  	snprintf(priv->phy_name, sizeof(priv->phy_name), PHY_ID_FMT,
>  		 priv->mdio->id, priv->phy_addr);
> 

Wrong commit message. I'll send a new fix.

Colin

On 08.06.2021 17:58, Colin King wrote:

> From: Colin Ian King <colin.king@canonical.com>
> 
> The comparison of the u16 priv->phy_addr < 0 is always false because
> phy_addr is unsigned. Fix this by assigning the return from the call
> to function asix_read_phy_addr to int ret and using this for the
> less than zero error check comparison.
> 
> Addresses-Coverity: ("Unsigned compared against 0")
> Fixes: e532a096be0e ("net: usb: asix: ax88772: add phylib support")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
>   drivers/net/usb/asix_devices.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
> index 57dafb3262d9..211c5a87eb15 100644
> --- a/drivers/net/usb/asix_devices.c
> +++ b/drivers/net/usb/asix_devices.c
> @@ -704,9 +704,10 @@ static int ax88772_init_phy(struct usbnet *dev)
>   	struct asix_common_private *priv = dev->driver_priv;
>   	int ret;
>   
> -	priv->phy_addr = asix_read_phy_addr(dev, true);
> -	if (priv->phy_addr < 0)
> +	ret = asix_read_phy_addr(dev, true);
> +	if (ret < 0)
>   		return priv->phy_addr;

    It's not yet assigned at this point, should be:

		return ret;

> +	priv->phy_addr = ret;

    Assigned only here. :-)

>   	snprintf(priv->phy_name, sizeof(priv->phy_name), PHY_ID_FMT,
>   		 priv->mdio->id, priv->phy_addr);

MBR, Sergei