fjes: Handle workqueue allocation failure

In the highly unlikely event that we fail to allocate either of the
"/txrx" or "/control" workqueues, we should bail cleanly rather than
blindly march on with NULL queue pointer(s) installed in the
'fjes_adapter' instance.

Cc: "David S. Miller" <davem@davemloft.net>
Reported-by: Nicolas Waisman <nico@semmle.com>
Link: https://lore.kernel.org/lkml/CADJ_3a8WFrs5NouXNqS5WYe7rebFP+_A5CheeqAyD_p7DFJJcg@mail.gmail.com/Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/fjes/fjes_main.c

@@ -1237,8 +1237,17 @@ static int fjes_probe(struct platform_device *plat_dev)
 	adapter->open_guard = false;
 
 	adapter->txrx_wq = alloc_workqueue(DRV_NAME "/txrx", WQ_MEM_RECLAIM, 0);
+	if (unlikely(!adapter->txrx_wq)) {
+		err = -ENOMEM;
+		goto err_free_netdev;
+	}
+
 	adapter->control_wq = alloc_workqueue(DRV_NAME "/control",
 					      WQ_MEM_RECLAIM, 0);
+	if (unlikely(!adapter->control_wq)) {
+		err = -ENOMEM;
+		goto err_free_txrx_wq;
+	}
 
 	INIT_WORK(&adapter->tx_stall_task, fjes_tx_stall_task);
 	INIT_WORK(&adapter->raise_intr_rxdata_task,
@@ -1255,7 +1264,7 @@ static int fjes_probe(struct platform_device *plat_dev)
 	hw->hw_res.irq = platform_get_irq(plat_dev, 0);
 	err = fjes_hw_init(&adapter->hw);
 	if (err)
-		goto err_free_netdev;
+		goto err_free_control_wq;
 
 	/* setup MAC address (02:00:00:00:00:[epid])*/
 	netdev->dev_addr[0] = 2;
@@ -1277,6 +1286,10 @@ static int fjes_probe(struct platform_device *plat_dev)
 
 err_hw_exit:
 	fjes_hw_exit(&adapter->hw);
+err_free_control_wq:
+	destroy_workqueue(adapter->control_wq);
+err_free_txrx_wq:
+	destroy_workqueue(adapter->txrx_wq);
 err_free_netdev:
 	free_netdev(netdev);
 err_out: