net: mscc: ocelot: check return value after calling platform_get_resource()

It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/ocelot/seville_vsc9953.c b/drivers/net/dsa/ocelot/seville_vsc9953.c
index 84f93a8..deae923 100644 (file)
--- a/drivers/net/dsa/ocelot/seville_vsc9953.c
+++ b/drivers/net/dsa/ocelot/seville_vsc9953.c
@@ -1206,6 +1206,11 @@ static int seville_probe(struct platform_device *pdev)
        felix->info = &seville_info_vsc9953;
 
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!res) {
+               err = -EINVAL;
+               dev_err(&pdev->dev, "Invalid resource\n");
+               goto err_alloc_felix;
+       }
        felix->switch_base = res->start;
 
        ds = kzalloc(sizeof(struct dsa_switch), GFP_KERNEL);