1 files changed, 21 insertions, 0 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 7b013fb0d27f..f1c726d94f47 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1433,10 +1433,31 @@ int ieee80211_monitor_start_xmit(struct sk_buff *skb,
                                  struct net_device *dev)
 {
         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+        struct ieee80211_channel *chan = local->hw.conf.channel;
         struct ieee80211_radiotap_header *prthdr =
                 (struct ieee80211_radiotap_header *)skb->data;
         u16 len_rthdr;
 
+        /*
+         * Frame injection is not allowed if beaconing is not allowed
+         * or if we need radar detection. Beaconing is usually not allowed when
+         * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
+         * Passive scan is also used in world regulatory domains where
+         * your country is not known and as such it should be treated as
+         * NO TX unless the channel is explicitly allowed in which case
+         * your current regulatory domain would not have the passive scan
+         * flag.
+         *
+         * Since AP mode uses monitor interfaces to inject/TX management
+         * frames we can make AP mode the exception to this rule once it
+         * supports radar detection as its implementation can deal with
+         * radar detection by itself. We can do that later by adding a
+         * monitor flag interfaces used for AP support.
+         */
+        if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
+             IEEE80211_CHAN_PASSIVE_SCAN)))
+                goto fail;
+
         /* check for not even having the fixed radiotap header part */
         if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
                 goto fail; /* too short to be possibly valid */