From a9e840a2081ed28c2b7caa6a9a0041c950b3c37d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 19 Apr 2017 09:59:22 -0700 Subject: [PATCH] cx82310_eth: 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: cc28a20e77b2 ("introduce cx82310_eth: Conexant CX82310-based ADSL router USB ethernet driver") Signed-off-by: Eric Dumazet Cc: James Hughes Signed-off-by: David S. Miller --- drivers/net/usb/cx82310_eth.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) --- a/drivers/net/usb/cx82310_eth.c +++ b/drivers/net/usb/cx82310_eth.c @@ -293,12 +293,9 @@ static struct sk_buff *cx82310_tx_fixup( { int len = skb->len; - if (skb_headroom(skb) < 2) { - struct sk_buff *skb2 = skb_copy_expand(skb, 2, 0, flags); + if (skb_cow_head(skb, 2)) { dev_kfree_skb_any(skb); - skb = skb2; - if (!skb) - return NULL; + return NULL; } skb_push(skb, 2);