lan78xx: use skb_cow_head() to deal with cloned skbs
We need to ensure there is enough headroom to push extra header,
but we also need to check if we are allowed to change headers.
skb_cow_head() is the proper helper to deal with this.
Fixes: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Cc: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 9889a70..636f48f 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2607,14 +2607,9 @@
{
u32 tx_cmd_a, tx_cmd_b;
- if (skb_headroom(skb) < TX_OVERHEAD) {
- struct sk_buff *skb2;
-
- skb2 = skb_copy_expand(skb, TX_OVERHEAD, 0, flags);
+ if (skb_cow_head(skb, TX_OVERHEAD)) {
dev_kfree_skb_any(skb);
- skb = skb2;
- if (!skb)
- return NULL;
+ return NULL;
}
if (lan78xx_linearize(skb) < 0)