4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
commit d4ca73591916b760478d2b04334d5dcadc028e9c upstream.
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@xxxxxxxxxx>
Cc: James Hughes <james.hughes@xxxxxxxxxxxxxxx>
Cc: Woojung Huh <woojung.huh@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/usb/lan78xx.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2050,14 +2050,9 @@ static struct sk_buff *lan78xx_tx_prep(s
{
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)