From: Lorenzo Bianconi <lorenzo@xxxxxxxxxx> [ Upstream commit 3e8f7abcc3473bc9603323803aeaed4ffcc3a2ab ] Fix possible out-of-bound access in ieee80211_get_rate_duration routine as reported by the following UBSAN report: UBSAN: array-index-out-of-bounds in net/mac80211/airtime.c:455:47 index 15 is out of range for type 'u16 [12]' CPU: 2 PID: 217 Comm: kworker/u32:10 Not tainted 6.1.0-060100rc3-generic Hardware name: Acer Aspire TC-281/Aspire TC-281, BIOS R01-A2 07/18/2017 Workqueue: mt76 mt76u_tx_status_data [mt76_usb] Call Trace: <TASK> show_stack+0x4e/0x61 dump_stack_lvl+0x4a/0x6f dump_stack+0x10/0x18 ubsan_epilogue+0x9/0x43 __ubsan_handle_out_of_bounds.cold+0x42/0x47 ieee80211_get_rate_duration.constprop.0+0x22f/0x2a0 [mac80211] ? ieee80211_tx_status_ext+0x32e/0x640 [mac80211] ieee80211_calc_rx_airtime+0xda/0x120 [mac80211] ieee80211_calc_tx_airtime+0xb4/0x100 [mac80211] mt76x02_send_tx_status+0x266/0x480 [mt76x02_lib] mt76x02_tx_status_data+0x52/0x80 [mt76x02_lib] mt76u_tx_status_data+0x67/0xd0 [mt76_usb] process_one_work+0x225/0x400 worker_thread+0x50/0x3e0 ? process_one_work+0x400/0x400 kthread+0xe9/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 Fixes: db3e1c40cf2f ("mac80211: Import airtime calculation code from mt76") Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx> Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxx> Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/mac80211/airtime.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/mac80211/airtime.c b/net/mac80211/airtime.c index 26d2f8ba7029..758ef63669e7 100644 --- a/net/mac80211/airtime.c +++ b/net/mac80211/airtime.c @@ -457,6 +457,9 @@ static u32 ieee80211_get_rate_duration(struct ieee80211_hw *hw, (status->encoding == RX_ENC_HE && streams > 8))) return 0; + if (idx >= MCS_GROUP_RATES) + return 0; + duration = airtime_mcs_groups[group].duration[idx]; duration <<= airtime_mcs_groups[group].shift; *overhead = 36 + (streams << 2); -- 2.35.1