BugLink: https://bugs.launchpad.net/bugs/1828420

commit 4856bfd2 upstream.

There are several scenarios in which mac80211 can call drv_wake_tx_queue
after ieee80211_restart_hw has been called and has not yet completed.
Driver private structs are considered uninitialized until mac80211 has
uploaded the vifs, stations and keys again, so using private tx queue
data during that time is not safe.

The driver can also not rely on drv_reconfig_complete to figure out when
it is safe to accept drv_wake_tx_queue calls again, because it is only
called after all tx queues are woken again.

To fix this, bail out early in drv_wake_tx_queue if local->in_reconfig
is set.

Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>