This is a note to let you know that I've just added the patch titled mac80211: track only QoS data frames for admission control to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mac80211-track-only-qos-data-frames-for-admission-co.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0cd76e0a2da4d4039f4bcefd574e524572f5a20b Author: Johannes Berg <johannes.berg@xxxxxxxxx> Date: Mon Nov 22 12:47:40 2021 +0100 mac80211: track only QoS data frames for admission control [ Upstream commit d5e568c3a4ec2ddd23e7dc5ad5b0c64e4f22981a ] 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@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 02219b3abca5 ("mac80211: add WMM admission control support") Link: https://lore.kernel.org/r/20211122124737.dad29e65902a.Ieb04587afacb27c14e0de93ec1bfbefb238cc2a0@changeid Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index cbcb60face2c5..e5c4a72f8e571 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -2351,11 +2351,18 @@ static void ieee80211_sta_tx_wmm_ac_notify(struct ieee80211_sub_if_data *sdata, u16 tx_time) { struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; - u16 tid = ieee80211_get_tid(hdr); - int ac = ieee80211_ac_from_tid(tid); - struct ieee80211_sta_tx_tspec *tx_tspec = &ifmgd->tx_tspec[ac]; + u16 tid; + int ac; + struct ieee80211_sta_tx_tspec *tx_tspec; unsigned long now = jiffies; + if (!ieee80211_is_data_qos(hdr->frame_control)) + return; + + tid = ieee80211_get_tid(hdr); + ac = ieee80211_ac_from_tid(tid); + tx_tspec = &ifmgd->tx_tspec[ac]; + if (likely(!tx_tspec->admitted_time)) return;