Merge branch 'packet-fixes'

Daniel Borkmann says:

====================
packet fixes

Fixes a couple of issues in packet sockets, i.e. on TX ring side. See
individual patches for details.

v2 -> v3:
 - First two patches unchanged, kept Jason's Ack
 - Reworked 3rd patch and split into 3:
  - check for dev type as discussed with Willem
  - infer skb->protocol
  - fix max len for dgram
v1 -> v2:
 - Added patch 2 as suggested by Dave
 - Rest is unchanged from previous submission
====================

Signed-off-by: David S. Miller <davem@davemloft.net>