From: Moon Hee Lee Date: Thu, 3 Jul 2025 19:37:57 +0000 (-0700) Subject: wifi: mac80211: reject VHT opmode for unsupported channel widths X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=58fcb1b4287ce38850402bb2bb16d09bf77b91d9;p=linux-block.git wifi: mac80211: reject VHT opmode for unsupported channel widths 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@syzkaller.appspotmail.com 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@syzkaller.appspotmail.com Signed-off-by: Moon Hee Lee Link: https://patch.msgid.link/20250703193756.46622-2-moonhee.lee.ca@gmail.com Signed-off-by: Johannes Berg --- diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index d9d88f2f2831..954795b0fe48 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1959,6 +1959,20 @@ 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 */