[PATCH 4.16 20/48] net: ethernet: davinci_emac: fix error handling in probe()

[Greg Kroah-Hartman]

4.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 8005b09d99fac78e6f5fb9da30b5ae94840af03b ]

The current error handling code has an issue where it does:

	if (priv->txchan)
		cpdma_chan_destroy(priv->txchan);

The problem is that ->txchan is either valid or an error pointer (which
would lead to an Oops).  I've changed it to use multiple error labels so
that the test can be removed.

Also there were some missing calls to netif_napi_del().

Fixes: 3ef0fdb2342c ("net: davinci_emac: switch to new cpdma layer")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/ti/davinci_emac.c |   22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

--- a/drivers/net/ethernet/ti/davinci_emac.c
+++ b/drivers/net/ethernet/ti/davinci_emac.c
@@ -1873,7 +1873,7 @@ static int davinci_emac_probe(struct pla
 	if (IS_ERR(priv->txchan)) {
 		dev_err(&pdev->dev, "error initializing tx dma channel\n");
 		rc = PTR_ERR(priv->txchan);
-		goto no_cpdma_chan;
+		goto err_free_dma;
 	}
 
 	priv->rxchan = cpdma_chan_create(priv->dma, EMAC_DEF_RX_CH,
@@ -1881,14 +1881,14 @@ static int davinci_emac_probe(struct pla
 	if (IS_ERR(priv->rxchan)) {
 		dev_err(&pdev->dev, "error initializing rx dma channel\n");
 		rc = PTR_ERR(priv->rxchan);
-		goto no_cpdma_chan;
+		goto err_free_txchan;
 	}
 
 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!res) {
 		dev_err(&pdev->dev, "error getting irq res\n");
 		rc = -ENOENT;
-		goto no_cpdma_chan;
+		goto err_free_rxchan;
 	}
 	ndev->irq = res->start;
 
@@ -1914,7 +1914,7 @@ static int davinci_emac_probe(struct pla
 		pm_runtime_put_noidle(&pdev->dev);
 		dev_err(&pdev->dev, "%s: failed to get_sync(%d)\n",
 			__func__, rc);
-		goto no_cpdma_chan;
+		goto err_napi_del;
 	}
 
 	/* register the network device */
@@ -1924,7 +1924,7 @@ static int davinci_emac_probe(struct pla
 		dev_err(&pdev->dev, "error in register_netdev\n");
 		rc = -ENODEV;
 		pm_runtime_put(&pdev->dev);
-		goto no_cpdma_chan;
+		goto err_napi_del;
 	}
 
 
@@ -1937,11 +1937,13 @@ static int davinci_emac_probe(struct pla
 
 	return 0;
 
-no_cpdma_chan:
-	if (priv->txchan)
-		cpdma_chan_destroy(priv->txchan);
-	if (priv->rxchan)
-		cpdma_chan_destroy(priv->rxchan);
+err_napi_del:
+	netif_napi_del(&priv->napi);
+err_free_rxchan:
+	cpdma_chan_destroy(priv->rxchan);
+err_free_txchan:
+	cpdma_chan_destroy(priv->txchan);
+err_free_dma:
 	cpdma_ctlr_destroy(priv->dma);
 no_pdata:
 	if (of_phy_is_fixed_link(np))