linux-kernel - [PATCH net-next v1 1/6] net: usb: lan78xx: Add error handling to lan78xx_get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20241216120941.1690908-2-o.rempel@pengutronix.de>
Date: Mon, 16 Dec 2024 13:09:36 +0100
From: Oleksij Rempel <o.rempel@...gutronix.de>
To: "David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>,
	Woojung Huh <woojung.huh@...rochip.com>,
	Andrew Lunn <andrew+netdev@...n.ch>
Cc: Oleksij Rempel <o.rempel@...gutronix.de>,
	kernel@...gutronix.de,
	linux-kernel@...r.kernel.org,
	netdev@...r.kernel.org,
	UNGLinuxDriver@...rochip.com,
	Phil Elwell <phil@...pberrypi.org>
Subject: [PATCH net-next v1 1/6] net: usb: lan78xx: Add error handling to lan78xx_get_regs

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. Drop all previously logged registers to signal
inconsistent readings to the user space. This ensures that invalid data
is not returned to users.

Signed-off-by: Oleksij Rempel <o.rempel@...gutronix.de>
---
 drivers/net/usb/lan78xx.c | 36 ++++++++++++++++++++++++++++++------
 1 file changed, 30 insertions(+), 6 deletions(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 4661d131b190..270345fcad65 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2108,20 +2108,44 @@ 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);
+	unsigned int data_count = 0;
+	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]);
+			goto clean_data;
+		}
+
+		data_count++;
+	}
 
 	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);
+			goto clean_data;
+		}
+
+		data[i] = ret;
+		data_count++;
+	}
+
+	return;
+
+clean_data:
+	memset(data, 0, data_count * sizeof(u32));
 }
 
 static const struct ethtool_ops lan78xx_ethtool_ops = {
-- 
2.39.5