@@ -304,24 +304,27 @@ static int ch9200_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
static int get_mac_address(struct usbnet *dev, unsigned char *data)
{
- int err = 0;
unsigned char mac_addr[0x06];
- int rd_mac_len = 0;
+ int rd_mac_len;
netdev_dbg(dev->net, "%s:\n\tusbnet VID:%0x PID:%0x\n", __func__,
le16_to_cpu(dev->udev->descriptor.idVendor),
le16_to_cpu(dev->udev->descriptor.idProduct));
- memset(mac_addr, 0, sizeof(mac_addr));
- rd_mac_len = control_read(dev, REQUEST_READ, 0,
- MAC_REG_STATION_L, mac_addr, 0x02,
- CONTROL_TIMEOUT_MS);
- rd_mac_len += control_read(dev, REQUEST_READ, 0, MAC_REG_STATION_M,
- mac_addr + 2, 0x02, CONTROL_TIMEOUT_MS);
- rd_mac_len += control_read(dev, REQUEST_READ, 0, MAC_REG_STATION_H,
- mac_addr + 4, 0x02, CONTROL_TIMEOUT_MS);
- if (rd_mac_len != ETH_ALEN)
- err = -EINVAL;
+ rd_mac_len = control_read(dev, REQUEST_READ, 0, MAC_REG_STATION_L,
+ mac_addr, 0x02, CONTROL_TIMEOUT_MS);
+ if (rd_mac_len < 0)
+ return rd_mac_len;
+
+ rd_mac_len = control_read(dev, REQUEST_READ, 0, MAC_REG_STATION_M,
+ mac_addr + 2, 0x02, CONTROL_TIMEOUT_MS);
+ if (rd_mac_len < 0)
+ return rd_mac_len;
+
+ rd_mac_len = control_read(dev, REQUEST_READ, 0, MAC_REG_STATION_H,
+ mac_addr + 4, 0x02, CONTROL_TIMEOUT_MS);
+ if (rd_mac_len < 0)
+ return rd_mac_len;
data[0] = mac_addr[5];
data[1] = mac_addr[4];
@@ -330,7 +333,7 @@ static int get_mac_address(struct usbnet *dev, unsigned char *data)
data[4] = mac_addr[1];
data[5] = mac_addr[0];
- return err;
+ return 0;
}
static int ch9200_bind(struct usbnet *dev, struct usb_interface *intf)
@@ -386,6 +389,9 @@ static int ch9200_bind(struct usbnet *dev, struct usb_interface *intf)
CONTROL_TIMEOUT_MS);
retval = get_mac_address(dev, addr);
+ if (retval < 0)
+ return retval;
+
eth_hw_addr_set(dev->net, addr);
return retval;
The get_mac_address() function has an issue where it does not directly check the return value of each control_read(), instead it sums up the return values and checks them all at the end which means if any call to control_read() fails the function just continues on. Handle this by validating the return value of each call and fail fast and early instead of continuing. Fixes: 4a476bd6d1d9 ("usbnet: New driver for QinHeng CH9200 devices") Signed-off-by: Qasim Ijaz <qasdev00@gmail.com> --- drivers/net/usb/ch9200.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-)