[PATCH 4.19 121/168] fsl/fman: fix dereference null return value

[Greg Kroah-Hartman]

From: Florinel Iordache <florinel.iordache@xxxxxxx>

[ 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@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/freescale/fman/fman_port.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/freescale/fman/fman_port.c b/drivers/net/ethernet/freescale/fman/fman_port.c
index ee82ee1384eb3..47f6fee1f3964 100644
--- 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;
-- 
2.25.1