-From b7c6d2675899cfff0180412c63fc9cbd5bacdb4d Mon Sep 17 00:00:00 2001
-From: Eric Dumazet <edumazet@google.com>
-Date: Wed, 19 Apr 2017 09:59:21 -0700
-Subject: [PATCH] smsc75xx: 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: d0cad871703b ("smsc75xx: SMSC LAN75xx USB gigabit ethernet adapter driver")
-Signed-off-by: Eric Dumazet <edumazet@google.com>
-Cc: James Hughes <james.hughes@raspberrypi.org>
-Signed-off-by: David S. Miller <davem@davemloft.net>
----
- drivers/net/usb/smsc75xx.c | 8 ++------
- 1 file changed, 2 insertions(+), 6 deletions(-)
-
---- a/drivers/net/usb/smsc75xx.c
-+++ b/drivers/net/usb/smsc75xx.c
-@@ -2193,13 +2193,9 @@ static struct sk_buff *smsc75xx_tx_fixup
- {
- u32 tx_cmd_a, tx_cmd_b;
-
-- if (skb_headroom(skb) < SMSC75XX_TX_OVERHEAD) {
-- struct sk_buff *skb2 =
-- skb_copy_expand(skb, SMSC75XX_TX_OVERHEAD, 0, flags);
-+ if (skb_cow_head(skb, SMSC75XX_TX_OVERHEAD)) {
- dev_kfree_skb_any(skb);
-- skb = skb2;
-- if (!skb)
-- return NULL;
-+ return NULL;
- }
-
- tx_cmd_a = (u32)(skb->len & TX_CMD_A_LEN) | TX_CMD_A_FCS;