2021-06-08 15:01:27

by Colin King

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

From: Colin Ian King <[email protected]>

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 <[email protected]>
---
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);
--
2.31.1


2021-06-09 02:22:05

by Colin King

[permalink] [raw]
Subject: NAK: [PATCH][next] net: usb: asix: ax88772: Fix less than zero comparison of a u16

On 08/06/2021 15:58, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> 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 <[email protected]>
> ---
> 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

2021-06-09 14:15:54

by Sergei Shtylyov

[permalink] [raw]
Subject: Re: [PATCH][next] net: usb: asix: ax88772: Fix less than zero comparison of a u16

On 08.06.2021 17:58, Colin King wrote:

> From: Colin Ian King <[email protected]>
>
> 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 <[email protected]>
> ---
> 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