4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Felix Fietkau <nbd@xxxxxxxx> commit 4f2bdb3c5e3189297e156b3ff84b140423d64685 upstream. When moving a station out of a VLAN and deleting the VLAN afterwards, the fast_rx entry still holds a pointer to the VLAN's netdev, which can cause use-after-free bugs. Fix this by immediately calling ieee80211_check_fast_rx after the VLAN change. Cc: stable@xxxxxxxxxxxxxxx Reported-by: ranygh@xxxxxxxxxx Signed-off-by: Felix Fietkau <nbd@xxxxxxxx> Link: https://msgid.link/20240316074336.40442-1-nbd@xxxxxxxx Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/mac80211/cfg.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1548,15 +1548,14 @@ static int ieee80211_change_station(stru } if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && - sta->sdata->u.vlan.sta) { - ieee80211_clear_fast_rx(sta); + sta->sdata->u.vlan.sta) RCU_INIT_POINTER(sta->sdata->u.vlan.sta, NULL); - } if (test_sta_flag(sta, WLAN_STA_AUTHORIZED)) ieee80211_vif_dec_num_mcast(sta->sdata); sta->sdata = vlansdata; + ieee80211_check_fast_rx(sta); ieee80211_check_fast_xmit(sta); if (test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
