4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> commit d532c1082f68176363ed766d09bf187616e282fe 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: c9b37458e956 ("USB2NET : SR9700 : One chip USB 1.1 USB2NET SR9700Device Driver Support") Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: James Hughes <james.hughes@xxxxxxxxxxxxxxx> 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/sr9700.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -456,14 +456,9 @@ static struct sk_buff *sr9700_tx_fixup(s len = skb->len; - if (skb_headroom(skb) < SR_TX_OVERHEAD) { - struct sk_buff *skb2; - - skb2 = skb_copy_expand(skb, SR_TX_OVERHEAD, 0, flags); + if (skb_cow_head(skb, SR_TX_OVERHEAD)) { dev_kfree_skb_any(skb); - skb = skb2; - if (!skb) - return NULL; + return NULL; } __skb_push(skb, SR_TX_OVERHEAD);