mac80211: Check port authorization in the ieee80211_tx_dequeue() case

mac80211: Check port authorization in the ieee80211_tx_dequeue() case

mac80211 used to check port authorization in the Data frame enqueue case
when going through start_xmit(). However, that authorization status may
change while the frame is waiting in a queue. Add a similar check in the
dequeue case to avoid sending previously accepted frames after
authorization change. This provides additional protection against
potential leaking of frames after a station has been disconnected and
the keys for it are being removed.

Cc: stable@vger.kernel.org
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Link: https://lore.kernel.org/r/20200326155133.ced84317ea29.I34d4c47cd8cc8a4042b38a76f16a601fbcbfd9b3@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>