mac80211: track only QoS data frames for admission control

stable inclusion
from stable-v4.19.222
commit 69f054d6642c8f6173724ce17e7ee3ff66b8f682
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA6SH2
CVE: CVE-2021-47602

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=69f054d6642c8f6173724ce17e7ee3ff66b8f682



--------------------------------

[ Upstream commit d5e568c3 ]

For admission control, obviously all of that only works for
QoS data frames, otherwise we cannot even access the QoS
field in the header.

Syzbot reported (see below) an uninitialized value here due
to a status of a non-QoS nullfunc packet, which isn't even
long enough to contain the QoS header.

Fix this to only do anything for QoS data packets.

Reported-by:  <syzbot+614e82b88a1a4973e534@syzkaller.appspotmail.com>
Fixes: 02219b3a ("mac80211: add WMM admission control support")
Link: https://lore.kernel.org/r/20211122124737.dad29e65902a.Ieb04587afacb27c14e0de93ec1bfbefb238cc2a0@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com>