1 From 6bc6895bdd6744e0136eaa4a11fbdb20a7db4e40 Mon Sep 17 00:00:00 2001
2 From: Eric Dumazet <edumazet@google.com>
3 Date: Wed, 19 Apr 2017 09:59:25 -0700
4 Subject: [PATCH] ch9200: use skb_cow_head() to deal with cloned skbs
6 We need to ensure there is enough headroom to push extra header,
7 but we also need to check if we are allowed to change headers.
9 skb_cow_head() is the proper helper to deal with this.
11 Fixes: 4a476bd6d1d9 ("usbnet: New driver for QinHeng CH9200 devices")
12 Signed-off-by: Eric Dumazet <edumazet@google.com>
13 Cc: James Hughes <james.hughes@raspberrypi.org>
14 Cc: Matthew Garrett <mjg59@srcf.ucam.org>
15 Signed-off-by: David S. Miller <davem@davemloft.net>
17 drivers/net/usb/ch9200.c | 9 ++-------
18 1 file changed, 2 insertions(+), 7 deletions(-)
20 --- a/drivers/net/usb/ch9200.c
21 +++ b/drivers/net/usb/ch9200.c
22 @@ -254,14 +254,9 @@ static struct sk_buff *ch9200_tx_fixup(s
26 - if (skb_headroom(skb) < tx_overhead) {
27 - struct sk_buff *skb2;
29 - skb2 = skb_copy_expand(skb, tx_overhead, 0, flags);
30 + if (skb_cow_head(skb, tx_overhead)) {
31 dev_kfree_skb_any(skb);
38 __skb_push(skb, tx_overhead);