usbnet: avoid integer overflow in start_xmit

transfer_buffer_length is of type u32. It's therefore wrong to assign it
to a signed integer. This patch avoids the overflow.

It's worth noting that entry->length here is a long; perhaps it would be
beneficial at somepoint to change this to be unsigned as well, if
nothing else relies on its signedness for error conditions or the like.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 733f4feb2ef3c5f11bbf99af962ecbb77253314b..3c86b107275a899f3748e4cfee82ab2bb43aff6b 100644 (file)
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1285,7 +1285,7 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
                                     struct net_device *net)
 {
        struct usbnet           *dev = netdev_priv(net);
-       int                     length;
+       unsigned int                    length;
        struct urb              *urb = NULL;
        struct skb_data         *entry;
        struct driver_info      *info = dev->driver_info;
@@ -1413,7 +1413,7 @@ not_drop:
                }
        } else
                netif_dbg(dev, tx_queued, dev->net,
-                         "> tx, len %d, type 0x%x\n", length, skb->protocol);
+                         "> tx, len %u, type 0x%x\n", length, skb->protocol);
 #ifdef CONFIG_PM
 deferred:
 #endif