Merge branch 'bridge-stale-ptrs'

Nikolay Aleksandrov says:

====================
net: bridge: fix possible stale skb pointers

In the bridge driver we have a couple of places which call pskb_may_pull
but we've cached skb pointers before that and use them after which can
lead to out-of-bounds/stale pointer use. I've had these in my "to fix"
list for some time and now we got a report (patch 01) so here they are.
Patches 02-04 are fixes based on code inspection. Also patch 01 was
tested by Martin Weinelt, Martin if you don't mind please add your
tested-by tag to it by replying with Tested-by: name <email>.
I've also briefly tested the set by trying to exercise those code paths.
====================

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