mac80211: set info->control.hw_key for encap offload packets

This is needed for drivers that don't do the key lookup themselves
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20200908123702.88454-5-nbd@nbd.nameSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/tx.c

@@ -4194,6 +4194,7 @@ static void ieee80211_8023_xmit(struct ieee80211_sub_if_data *sdata,
 {
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_key *key;
 	struct tid_ampdu_tx *tid_tx;
 	u8 tid;
 
@@ -4242,6 +4243,10 @@ static void ieee80211_8023_xmit(struct ieee80211_sub_if_data *sdata,
 	info->control.flags |= IEEE80211_TX_CTRL_HW_80211_ENCAP;
 	info->control.vif = &sdata->vif;
 
+	key = rcu_dereference(sta->ptk[sta->ptk_idx]);
+	if (key)
+		info->control.hw_key = &key->conf;
+
 	ieee80211_tx_8023(sdata, skb, skb->len, sta, false);
 
 	return;