diff --git a/package/mac80211/patches/550-cfg80211_validate_mcast_rate.patch b/package/mac80211/patches/550-cfg80211_validate_mcast_rate.patch
new file mode 100644
index 0000000000000000000000000000000000000000..6d8f62df55e62411d85e170f96d3a9f2fbda33e0
--- /dev/null
+++ b/package/mac80211/patches/550-cfg80211_validate_mcast_rate.patch
@@ -0,0 +1,157 @@
+--- a/include/net/cfg80211.h
++++ b/include/net/cfg80211.h
+@@ -924,7 +924,7 @@ struct cfg80211_disassoc_request {
+  * @privacy: this is a protected network, keys will be configured
+  *	after joining
+  * @basic_rates: bitmap of basic rates to use when creating the IBSS
+- * @mcast_rate: multicast tx rate (in 100 kbps)
++ * @mcast_rate: per-band multicast rate index + 1 (0: disabled)
+  */
+ struct cfg80211_ibss_params {
+ 	u8 *ssid;
+@@ -936,7 +936,7 @@ struct cfg80211_ibss_params {
+ 	u32 basic_rates;
+ 	bool channel_fixed;
+ 	bool privacy;
+-	int mcast_rate;
++	int mcast_rate[IEEE80211_NUM_BANDS];
+ };
+ 
+ /**
+--- a/include/net/mac80211.h
++++ b/include/net/mac80211.h
+@@ -219,7 +219,7 @@ enum ieee80211_bss_change {
+  * @basic_rates: bitmap of basic rates, each bit stands for an
+  *	index into the rate table configured by the driver in
+  *	the current band.
+- * @mcast_rate: multicast rate for AP and Ad-Hoc (in 100 kbps)
++ * @mcast_rate: per-band multicast rate index + 1 (0: disabled)
+  * @bssid: The BSSID for this BSS
+  * @enable_beacon: whether beaconing should be enabled or not
+  * @channel_type: Channel type for this BSS -- the hardware might be
+@@ -259,7 +259,7 @@ struct ieee80211_bss_conf {
+ 	u16 assoc_capability;
+ 	u64 timestamp;
+ 	u32 basic_rates;
+-	u32 mcast_rate;
++	int mcast_rate[IEEE80211_NUM_BANDS];
+ 	u16 ht_operation_mode;
+ 	s32 cqm_rssi_thold;
+ 	u32 cqm_rssi_hyst;
+--- a/net/mac80211/ibss.c
++++ b/net/mac80211/ibss.c
+@@ -915,7 +915,8 @@ int ieee80211_ibss_join(struct ieee80211
+ 
+ 	sdata->u.ibss.privacy = params->privacy;
+ 	sdata->u.ibss.basic_rates = params->basic_rates;
+-	sdata->vif.bss_conf.mcast_rate = params->mcast_rate;
++	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
++	       sizeof(params->mcast_rate));
+ 
+ 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
+ 
+--- a/net/mac80211/rate.c
++++ b/net/mac80211/rate.c
+@@ -211,20 +211,11 @@ static bool rc_no_data_or_no_ack(struct 
+ 	return (info->flags & IEEE80211_TX_CTL_NO_ACK) || !ieee80211_is_data(fc);
+ }
+ 
+-static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, u32 mcast_rate,
++static void rc_send_low_broadcast(s8 *idx, u32 basic_rates,
+ 				  struct ieee80211_supported_band *sband)
+ {
+ 	u8 i;
+ 
+-	if (mcast_rate) {
+-		for (i = 0; i < sband->n_bitrates; i++) {
+-			if (sband->bitrates[i].bitrate == mcast_rate) {
+-				*idx = i;
+-				return;
+-			}
+-		}
+-	}
+-
+ 	if (basic_rates == 0)
+ 		return; /* assume basic rates unknown and accept rate */
+ 	if (*idx < 0)
+@@ -247,17 +238,25 @@ bool rate_control_send_low(struct ieee80
+ 			   struct ieee80211_tx_rate_control *txrc)
+ {
+ 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
++	struct ieee80211_supported_band *sband = txrc->sband;
++	int mcast_rate;
+ 
+ 	if (!sta || !priv_sta || rc_no_data_or_no_ack(txrc)) {
+ 		info->control.rates[0].idx = rate_lowest_index(txrc->sband, sta);
+ 		info->control.rates[0].count =
+ 			(info->flags & IEEE80211_TX_CTL_NO_ACK) ?
+ 			1 : txrc->hw->max_rate_tries;
+-		if (!sta && txrc->bss)
++		if (!sta && txrc->bss) {
++			mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
++			if (mcast_rate > 0) {
++				info->control.rates[0].idx = mcast_rate - 1;
++				return true;
++			}
++
+ 			rc_send_low_broadcast(&info->control.rates[0].idx,
+ 					      txrc->bss_conf->basic_rates,
+-					      txrc->bss_conf->mcast_rate,
+-					      txrc->sband);
++					      sband);
++		}
+ 		return true;
+ 	}
+ 	return false;
+--- a/net/wireless/nl80211.c
++++ b/net/wireless/nl80211.c
+@@ -3600,6 +3600,34 @@ static int nl80211_disassociate(struct s
+ 				      local_state_change);
+ }
+ 
++static bool
++nl80211_parse_mcast_rate(struct cfg80211_registered_device *rdev,
++			 int mcast_rate[IEEE80211_NUM_BANDS],
++			 int rateval)
++{
++	struct wiphy *wiphy = &rdev->wiphy;
++	bool found = false;
++	int band, i;
++
++	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
++		struct ieee80211_supported_band *sband;
++
++		sband = wiphy->bands[band];
++		if (!sband)
++			continue;
++
++		for (i = 0; i < sband->n_bitrates; i++) {
++			if (sband->bitrates[i].bitrate == rateval) {
++				mcast_rate[band] = i + 1;
++				found = true;
++				break;
++			}
++		}
++	}
++
++	return found;
++}
++
+ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
+ {
+ 	struct cfg80211_registered_device *rdev = info->user_ptr[0];
+@@ -3683,9 +3711,11 @@ static int nl80211_join_ibss(struct sk_b
+ 				return -EINVAL;
+ 		}
+ 	}
+-	if (info->attrs[NL80211_ATTR_MCAST_RATE])
+-		ibss.mcast_rate =
+-			nla_get_u32(info->attrs[NL80211_ATTR_MCAST_RATE]);
++
++	if (info->attrs[NL80211_ATTR_MCAST_RATE] &&
++	    !nl80211_parse_mcast_rate(rdev, ibss.mcast_rate,
++			nla_get_u32(info->attrs[NL80211_ATTR_MCAST_RATE])))
++		return -EINVAL;
+ 
+ 	if (ibss.privacy && info->attrs[NL80211_ATTR_KEYS]) {
+ 		connkeys = nl80211_parse_connkeys(rdev,