wifi: mt76: mt7996: check return value before accessing free_block_num

Check return value of mt7996_mcu_get_eeprom_free_block() first before
accessing free_block_num.

Fixes: 98686cd2 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices")
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -65,17 +65,23 @@ static int mt7996_eeprom_load(struct mt7996_dev *dev)
 	} else {
 		u8 free_block_num;
 		u32 block_num, i;
+		u32 eeprom_blk_size = MT7996_EEPROM_BLOCK_SIZE;
 
-		/* TODO: check free block event */
-		mt7996_mcu_get_eeprom_free_block(dev, &free_block_num);
-		/* efuse info not enough */
+		ret = mt7996_mcu_get_eeprom_free_block(dev, &free_block_num);
+		if (ret < 0)
+			return ret;
+
+		/* efuse info isn't enough */
 		if (free_block_num >= 59)
 			return -EINVAL;
 
 		/* read eeprom data from efuse */
-		block_num = DIV_ROUND_UP(MT7996_EEPROM_SIZE, MT7996_EEPROM_BLOCK_SIZE);
-		for (i = 0; i < block_num; i++)
-			mt7996_mcu_get_eeprom(dev, i * MT7996_EEPROM_BLOCK_SIZE);
+		block_num = DIV_ROUND_UP(MT7996_EEPROM_SIZE, eeprom_blk_size);
+		for (i = 0; i < block_num; i++) {
+			ret = mt7996_mcu_get_eeprom(dev, i * eeprom_blk_size);
+			if (ret < 0)
+				return ret;
+		}
 	}
 
 	return mt7996_check_eeprom(dev);

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

@@ -2927,8 +2927,9 @@ int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset)
 	bool valid;
 	int ret;
 
-	ret = mt76_mcu_send_and_get_msg(&dev->mt76, MCU_WM_UNI_CMD_QUERY(EFUSE_CTRL), &req,
-					sizeof(req), true, &skb);
+	ret = mt76_mcu_send_and_get_msg(&dev->mt76,
+					MCU_WM_UNI_CMD_QUERY(EFUSE_CTRL),
+					&req, sizeof(req), true, &skb);
 	if (ret)
 		return ret;