[PATCH net-next v1 04/11] net: usb: lan78xx: Add error handling to lan78xx_get_regs

Oleksij Rempel posted 11 patches 1 year ago
There is a newer version of this series
[PATCH net-next v1 04/11] net: usb: lan78xx: Add error handling to lan78xx_get_regs
Posted by Oleksij Rempel 1 year ago
Update `lan78xx_get_regs` to handle errors during register and PHY
reads.  Log warnings for failed reads and exit the function early if an
error occurs.  This ensures that invalid data is not returned to users.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 drivers/net/usb/lan78xx.c | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 5d318ff8b33d..62445aced7c6 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2112,20 +2112,35 @@ static void
 lan78xx_get_regs(struct net_device *netdev, struct ethtool_regs *regs,
 		 void *buf)
 {
-	u32 *data = buf;
-	int i, j;
 	struct lan78xx_net *dev = netdev_priv(netdev);
+	u32 *data = buf;
+	int i, j, ret;
 
 	/* Read Device/MAC registers */
-	for (i = 0; i < ARRAY_SIZE(lan78xx_regs); i++)
-		lan78xx_read_reg(dev, lan78xx_regs[i], &data[i]);
+	for (i = 0; i < ARRAY_SIZE(lan78xx_regs); i++) {
+		ret = lan78xx_read_reg(dev, lan78xx_regs[i], &data[i]);
+		if (ret < 0) {
+			netdev_warn(dev->net,
+				    "failed to read register 0x%08x\n",
+				    lan78xx_regs[i]);
+			return;
+		}
+	}
 
 	if (!netdev->phydev)
 		return;
 
 	/* Read PHY registers */
-	for (j = 0; j < 32; i++, j++)
-		data[i] = phy_read(netdev->phydev, j);
+	for (j = 0; j < 32; i++, j++) {
+		ret = phy_read(netdev->phydev, j);
+		if (ret < 0) {
+			netdev_warn(dev->net,
+				    "failed to read PHY register 0x%02x\n", j);
+			return;
+		}
+
+		data[i] = ret;
+	}
 }
 
 static const struct ethtool_ops lan78xx_ethtool_ops = {
-- 
2.39.5
Re: [PATCH net-next v1 04/11] net: usb: lan78xx: Add error handling to lan78xx_get_regs
Posted by Jakub Kicinski 1 year ago
On Mon,  9 Dec 2024 14:07:44 +0100 Oleksij Rempel wrote:
> Update `lan78xx_get_regs` to handle errors during register and PHY
> reads.  Log warnings for failed reads and exit the function early if an
> error occurs.  This ensures that invalid data is not returned to users.

Should we zero out all the returned regs, too? 
Make it more obvious we failed.
Re: [PATCH net-next v1 04/11] net: usb: lan78xx: Add error handling to lan78xx_get_regs
Posted by Andrew Lunn 1 year ago
On Mon, Dec 09, 2024 at 02:07:44PM +0100, Oleksij Rempel wrote:
> Update `lan78xx_get_regs` to handle errors during register and PHY
> reads.  Log warnings for failed reads and exit the function early if an
> error occurs.  This ensures that invalid data is not returned to users.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew