VHT operating mode notifications are not defined for channel widths below 20 MHz. In particular, 5 MHz and 10 MHz are not valid under the VHT specification and must be rejected. Without this check, malformed notifications using these widths may reach ieee80211_chan_width_to_rx_bw(), leading to a WARN_ON due to invalid input. This issue was reported by syzbot. Reject these unsupported widths early in sta_link_apply_parameters() when opmode_notif is used. The accepted set includes 20, 40, 80, 160, and 80+80 MHz, which are valid for VHT. While 320 MHz is not defined for VHT, it is allowed to avoid rejecting HE or EHT clients that may still send a VHT opmode notification. Reported-by: syzbot+ededba317ddeca8b3f08@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=ededba317ddeca8b3f08 Fixes: 751e7489c1d7 ("wifi: mac80211: expose ieee80211_chan_width_to_rx_bw() to drivers") Tested-by: syzbot+ededba317ddeca8b3f08@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Moon Hee Lee <moonhee.lee.ca@xxxxxxxxx> --- Changes in v2: - Dropped NL80211_CHAN_WIDTH_20_NOHT from the accepted channel widths. - Clarified in the commit message that 320 MHz is not defined for VHT but still allowed to support HE/EHT clients that may send a VHT opmode notification. net/mac80211/cfg.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 56540c3701ed..d76643d46150 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1981,6 +1981,20 @@ static int sta_link_apply_parameters(struct ieee80211_local *local, ieee80211_sta_init_nss(link_sta); if (params->opmode_notif_used) { + enum nl80211_chan_width width = link->conf->chanreq.oper.width; + + switch (width) { + case NL80211_CHAN_WIDTH_20: + case NL80211_CHAN_WIDTH_40: + case NL80211_CHAN_WIDTH_80: + case NL80211_CHAN_WIDTH_160: + case NL80211_CHAN_WIDTH_80P80: + case NL80211_CHAN_WIDTH_320: /* not VHT, allowed for HE/EHT */ + break; + default: + return -EINVAL; + } + /* returned value is only needed for rc update, but the * rc isn't initialized here yet, so ignore it */ -- 2.43.0