net: freescale: fix potential null pointer dereference

Add NULL check before dereferencing pointer _id_ in order to avoid
a potential NULL pointer dereference.

Addresses-Coverity-ID: 1397995
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/freescale/fsl_pq_mdio.c b/drivers/net/ethernet/freescale/fsl_pq_mdio.c
index 446c7b3..a10de1e 100644 (file)
--- a/drivers/net/ethernet/freescale/fsl_pq_mdio.c
+++ b/drivers/net/ethernet/freescale/fsl_pq_mdio.c
@@ -381,7 +381,7 @@ static int fsl_pq_mdio_probe(struct platform_device *pdev)
 {
        const struct of_device_id *id =
                of_match_device(fsl_pq_mdio_match, &pdev->dev);
-       const struct fsl_pq_mdio_data *data = id->data;
+       const struct fsl_pq_mdio_data *data;
        struct device_node *np = pdev->dev.of_node;
        struct resource res;
        struct device_node *tbi;
@@ -389,6 +389,13 @@ static int fsl_pq_mdio_probe(struct platform_device *pdev)
        struct mii_bus *new_bus;
        int err;
 
+       if (!id) {
+               dev_err(&pdev->dev, "Failed to match device\n");
+               return -ENODEV;
+       }
+
+       data = id->data;
+
        dev_dbg(&pdev->dev, "found %s compatible node\n", id->compatible);
 
        new_bus = mdiobus_alloc_size(sizeof(*priv));