wifi: mt76: mt7996: ensure 4-byte alignment for beacon commands

If TLV includes beacon content, its length might not be 4-byte aligned.
Make sure the length is aligned before sending beacon commands to FW.
Signed-off-by: Benjamin Lin <benjamin-jw.lin@mediatek.com>
Signed-off-by: Shayne Chen <shayne.chen@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7996/mcu.c

@@ -732,13 +732,10 @@ void mt7996_mcu_rx_event(struct mt7996_dev *dev, struct sk_buff *skb)
 static struct tlv *
 mt7996_mcu_add_uni_tlv(struct sk_buff *skb, u16 tag, u16 len)
 {
-	struct tlv *ptlv, tlv = {
-		.tag = cpu_to_le16(tag),
-		.len = cpu_to_le16(len),
-	};
+	struct tlv *ptlv = skb_put(skb, len);
 
-	ptlv = skb_put(skb, len);
-	memcpy(ptlv, &tlv, sizeof(tlv));
+	ptlv->tag = cpu_to_le16(tag);
+	ptlv->len = cpu_to_le16(len);
 
 	return ptlv;
 }
@@ -2522,7 +2519,7 @@ int mt7996_mcu_add_beacon(struct ieee80211_hw *hw,
 	info = IEEE80211_SKB_CB(skb);
 	info->hw_queue |= FIELD_PREP(MT_TX_HW_QUEUE_PHY, phy->mt76->band_idx);
 
-	len = sizeof(*bcn) + MT_TXD_SIZE + skb->len;
+	len = ALIGN(sizeof(*bcn) + MT_TXD_SIZE + skb->len, 4);
 	tlv = mt7996_mcu_add_uni_tlv(rskb, UNI_BSS_INFO_BCN_CONTENT, len);
 	bcn = (struct bss_bcn_content_tlv *)tlv;
 	bcn->enable = en;
@@ -2591,8 +2588,7 @@ int mt7996_mcu_beacon_inband_discov(struct mt7996_dev *dev,
 	info->band = band;
 	info->hw_queue |= FIELD_PREP(MT_TX_HW_QUEUE_PHY, phy->mt76->band_idx);
 
-	len = sizeof(*discov) + MT_TXD_SIZE + skb->len;
-
+	len = ALIGN(sizeof(*discov) + MT_TXD_SIZE + skb->len, 4);
 	tlv = mt7996_mcu_add_uni_tlv(rskb, UNI_BSS_INFO_OFFLOAD, len);
 
 	discov = (struct bss_inband_discovery_tlv *)tlv;

drivers/net/wireless/mediatek/mt76/mt7996/mcu.h

@@ -800,10 +800,10 @@ enum {
 					 sizeof(struct sta_rec_hdr_trans) +	\
 					 sizeof(struct tlv))
 
-#define MT7996_MAX_BEACON_SIZE		1342
+#define MT7996_MAX_BEACON_SIZE		1338
 #define MT7996_BEACON_UPDATE_SIZE	(sizeof(struct bss_req_hdr) +		\
 					 sizeof(struct bss_bcn_content_tlv) +	\
-					 MT_TXD_SIZE +				\
+					 4 + MT_TXD_SIZE +			\
 					 sizeof(struct bss_bcn_cntdwn_tlv) +	\
 					 sizeof(struct bss_bcn_mbss_tlv))
 #define MT7996_MAX_BSS_OFFLOAD_SIZE	(MT7996_MAX_BEACON_SIZE +		\