commit 6bc6895bdd6744e0136eaa4a11fbdb20a7db4e40
author Eric Dumazet <edumazet@google.com> Wed Apr 19 09:59:25 2017 -0700
committer David S. Miller <davem@davemloft.net> Fri Apr 21 13:24:06 2017 -0400
tree b110925dec762d275560dc72e189a8129d536159
parent d4ca73591916b760478d2b04334d5dcadc028e9c

ch9200: 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: 4a476bd6d1d9 ("usbnet: New driver for QinHeng CH9200 devices")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: David S. Miller <davem@davemloft.net>