In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: update channel list in reg notifier instead reg worker
Currently when ath11k gets a new channel list, it will be processed according to the following steps:
But ath11k will immediately execute step 3 after reg_work is just queued. Since step 2 is asynchronous, cfg80211 may not have completed handling the new channel list, which may leading to an out-of-bounds write error: BUG: KASAN: slab-out-of-bounds in ath11k_reg_update_chan_list Call Trace: ath11k_reg_update_chan_list+0xbfe/0xfe0 [ath11k] kfree+0x109/0x3a0 ath11k_regd_update+0x1cf/0x350 [ath11k] ath11k_regd_update_work+0x14/0x20 [ath11k] process_one_work+0xe35/0x14c0
Should ensure step 2 is completely done before executing step 3. Thus Wen raised patch[1]. When flag NL80211_REGDOM_SET_BY_DRIVER is set, cfg80211 will notify ath11k after step 2 is done.
So enable the flag NL80211_REGDOM_SET_BY_DRIVER then cfg80211 will notify ath11k after step 2 is done. At this time, there will be no KASAN bug during the execution of the step 3.
[1] https://patchwork.kernel.org/project/linux-wireless/patch/20230201065313.27203-1-quic_wgong@quicinc.com/
Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:HI:HA:H7.8/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H