ethernet: atheros: fix a memleak in atl1e_setup_ring_resources

In the error handling of 'offset > adapter->ring_size', the
tx_ring->tx_buffer allocated by kzalloc should be freed,
instead of 'goto failed' instantly.

Fixes: a6a5325 ("atl1e: Atheros L1E Gigabit Ethernet driver")
Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
Reviewed-by: Suman Ghosh <sumang@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: AlexiousLu

drivers/net/ethernet/atheros/atl1e/atl1e_main.c

@@ -866,10 +866,13 @@ static int atl1e_setup_ring_resources(struct atl1e_adapter *adapter)
 		netdev_err(adapter->netdev, "offset(%d) > ring size(%d) !!\n",
 			   offset, adapter->ring_size);
 		err = -1;
-		goto failed;
+		goto free_buffer;
 	}
 
 	return 0;
+free_buffer:
+	kfree(tx_ring->tx_buffer);
+	tx_ring->tx_buffer = NULL;
 failed:
 	if (adapter->ring_vir_addr != NULL) {
 		dma_free_coherent(&pdev->dev, adapter->ring_size,