cfg80211: leave invalid channels on regdomain change

When the regulatory settings change, some channels might become invalid.
Disconnect interfaces acting on these channels, after giving userspace
code a grace period to leave them.

This mode is currently opt-in, and not all interface operating modes are
supported for regulatory-enforcement checks. A wiphy that wishes to use
the new enforcement code must specify an appropriate regulatory flag,
and all its supported interface modes must be supported by the checking
code.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Luis R. Rodriguez <mcgrof@suse.com>
[fix some indentation, typos]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 4c2e501..53dda77 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -546,6 +546,20 @@
 		     !rdev->ops->tdls_cancel_channel_switch)))
 		return -EINVAL;
 
+	/*
+	 * if a wiphy has unsupported modes for regulatory channel enforcement,
+	 * opt-out of enforcement checking
+	 */
+	if (wiphy->interface_modes & ~(BIT(NL80211_IFTYPE_STATION) |
+				       BIT(NL80211_IFTYPE_P2P_CLIENT) |
+				       BIT(NL80211_IFTYPE_AP) |
+				       BIT(NL80211_IFTYPE_P2P_GO) |
+				       BIT(NL80211_IFTYPE_ADHOC) |
+				       BIT(NL80211_IFTYPE_P2P_DEVICE) |
+				       BIT(NL80211_IFTYPE_AP_VLAN) |
+				       BIT(NL80211_IFTYPE_MONITOR)))
+		wiphy->regulatory_flags |= REGULATORY_IGNORE_STALE_KICKOFF;
+
 	if (WARN_ON(wiphy->coalesce &&
 		    (!wiphy->coalesce->n_rules ||
 		     !wiphy->coalesce->n_patterns) &&