usbnet: ipheth: fix potential null pointer dereference in ipheth_carrier_set

_dev_ is being dereferenced before it is null checked, hence there
is a potential null pointer dereference.

Fix this by moving the pointer dereference after _dev_ has been null
checked.

Addresses-Coverity-ID: 1462020
Fixes: bb1b40c7cb86 ("usbnet: ipheth: prevent TX queue timeouts when device not ready")
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c
index ca71f6c03859..7275761a1177 100644
--- a/drivers/net/usb/ipheth.c
+++ b/drivers/net/usb/ipheth.c
@@ -291,12 +291,15 @@ static void ipheth_sndbulk_callback(struct urb *urb)
 
 static int ipheth_carrier_set(struct ipheth_device *dev)
 {
-        struct usb_device *udev = dev->udev;
+        struct usb_device *udev;
         int retval;
+
         if (!dev)
                 return 0;
         if (!dev->confirmed_pairing)
                 return 0;
+
+        udev = dev->udev;
         retval = usb_control_msg(udev,
                         usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
                         IPHETH_CMD_CARRIER_CHECK, /* request */