fsl/fman: fix dereference null return value

BugLink: https://bugs.launchpad.net/bugs/1892417
[ Upstream commit 0572054617f32670abab4b4e89a876954d54b704 ]

Check before using returned value to avoid dereferencing null pointer.

Fixes: 18a6c85fcc78 ("fsl/fman: Add FMan Port Support")
Signed-off-by: Florinel Iordache <florinel.iordache@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/drivers/net/ethernet/freescale/fman/fman_port.c b/drivers/net/ethernet/freescale/fman/fman_port.c
index ee82ee1384eb3160651ce4764f382c3873edaa91..47f6fee1f396436ecb8524675eda721379ee8e9b 100644 (file)
--- a/drivers/net/ethernet/freescale/fman/fman_port.c
+++ b/drivers/net/ethernet/freescale/fman/fman_port.c
@@ -1756,6 +1756,7 @@ static int fman_port_probe(struct platform_device *of_dev)
        struct fman_port *port;
        struct fman *fman;
        struct device_node *fm_node, *port_node;
+       struct platform_device *fm_pdev;
        struct resource res;
        struct resource *dev_res;
        u32 val;
@@ -1780,8 +1781,14 @@ static int fman_port_probe(struct platform_device *of_dev)
                goto return_err;
        }
 
-       fman = dev_get_drvdata(&of_find_device_by_node(fm_node)->dev);
+       fm_pdev = of_find_device_by_node(fm_node);
        of_node_put(fm_node);
+       if (!fm_pdev) {
+               err = -EINVAL;
+               goto return_err;
+       }
+
+       fman = dev_get_drvdata(&fm_pdev->dev);
        if (!fman) {
                err = -EINVAL;
                goto return_err;