From af9ef8f6eb55ce5798de98a3078bc7492a2b1677 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 19 Apr 2017 09:59:25 -0700 Subject: [PATCH] ch9200: use skb_cow_head() to deal with cloned skbs commit 6bc6895bdd6744e0136eaa4a11fbdb20a7db4e40 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: 4a476bd6d1d9 ("usbnet: New driver for QinHeng CH9200 devices") Signed-off-by: Eric Dumazet Cc: James Hughes Cc: Matthew Garrett Signed-off-by: David S. Miller Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- drivers/net/usb/ch9200.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/drivers/net/usb/ch9200.c b/drivers/net/usb/ch9200.c index 8a40202c0a17..c4f1c363e24b 100644 --- a/drivers/net/usb/ch9200.c +++ b/drivers/net/usb/ch9200.c @@ -254,14 +254,9 @@ static struct sk_buff *ch9200_tx_fixup(struct usbnet *dev, struct sk_buff *skb, tx_overhead = 0x40; len = skb->len; - 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; } __skb_push(skb, tx_overhead); -- 2.43.0