mac80211: don't WARN on short WMM parameters from AP
authorBrian Norris <briannorris@chromium.org>
Fri, 26 Jul 2019 22:47:58 +0000 (15:47 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 16 Aug 2019 08:12:52 +0000 (10:12 +0200)
commita566750c3a78b0dc78c328a88ded49db4f7876ea
treef87e1318d04d8a0e24acbedb126616e2bf9ce482
parentaf9d64f871cfe441508f116f31b49410453f96db
mac80211: don't WARN on short WMM parameters from AP

commit 05aaa5c97dce4c10a9e7eae2f1569a684e0c5ced upstream.

In a very similar spirit to commit c470bdc1aaf3 ("mac80211: don't WARN
on bad WMM parameters from buggy APs"), an AP may not transmit a
fully-formed WMM IE. For example, it may miss or repeat an Access
Category. The above loop won't catch that and will instead leave one of
the four ACs zeroed out. This triggers the following warning in
drv_conf_tx()

  wlan0: invalid CW_min/CW_max: 0/0

and it may leave one of the hardware queues unconfigured. If we detect
such a case, let's just print a warning and fall back to the defaults.

Tested with a hacked version of hostapd, intentionally corrupting the
IEs in hostapd_eid_wmm().

Cc: stable@vger.kernel.org
Signed-off-by: Brian Norris <briannorris@chromium.org>
Link: https://lore.kernel.org/r/20190726224758.210953-1-briannorris@chromium.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/mac80211/mlme.c