From: Nguyen Dinh Phi <phind.uet@xxxxxxxxx> commit 563fbefed46ae4c1f70cffb8eb54c02df480b2c2 upstream. If the userspace tools switch from NL80211_IFTYPE_P2P_GO to NL80211_IFTYPE_ADHOC via send_msg(NL80211_CMD_SET_INTERFACE), it does not call the cleanup cfg80211_stop_ap(), this leads to the initialization of in-use data. For example, this path re-init the sdata->assigned_chanctx_list while it is still an element of assigned_vifs list, and makes that linked list corrupt. Signed-off-by: Nguyen Dinh Phi <phind.uet@xxxxxxxxx> Reported-by: syzbot+bbf402b783eeb6d908db@xxxxxxxxxxxxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20211027173722.777287-1-phind.uet@xxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Fixes: ac800140c20e ("cfg80211: .stop_ap when interface is going down") Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/wireless/util.c | 1 + 1 file changed, 1 insertion(+) --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -1026,6 +1026,7 @@ int cfg80211_change_iface(struct cfg8021 switch (otype) { case NL80211_IFTYPE_AP: + case NL80211_IFTYPE_P2P_GO: cfg80211_stop_ap(rdev, dev, true); break; case NL80211_IFTYPE_ADHOC: