tree 47259e207d75594269f8bc4ace531ba250875abc
parent fc9c89b19c56813434c3d2967652a4fa6906926a
author Johannes Berg <johannes.berg@intel.com> 1492086229 +0200
committer Johannes Berg <johannes.berg@intel.com> 1492086953 +0200

mac80211: fix MU-MIMO follow-MAC mode

There are two bugs in the follow-MAC code:
 * it treats the radiotap header as the 802.11 header
   (therefore it can't possibly work)
 * it doesn't verify that the skb data it accesses is actually
   present in the header, which is mitigated by the first point

Fix this by moving all of this out into a separate function.
This function copies the data it needs using skb_copy_bits()
to make sure it can be accessed if it's paged, and offsets
that by the possibly present vendor radiotap header.

This also makes all those conditions more readable.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>