diff mbox series

[net-next] drivers: net: davinci_mdio: fix potential NULL dereference in davinci_mdio_probe()

Message ID 20200427094032.181184-1-weiyongjun1@huawei.com (mailing list archive)
State New, archived
Headers show
Series [net-next] drivers: net: davinci_mdio: fix potential NULL dereference in davinci_mdio_probe() | expand

Commit Message

Wei Yongjun April 27, 2020, 9:40 a.m. UTC
platform_get_resource() may fail and return NULL, so we should
better check it's return value to avoid a NULL pointer dereference
a bit later in the code.

This is detected by Coccinelle semantic patch.

@@
expression pdev, res, n, t, e, e1, e2;
@@

res = \(platform_get_resource\|platform_get_resource_byname\)(pdev, t, n);
+ if (!res)
+   return -EINVAL;
... when != res == NULL
e = devm_ioremap(e1, res->start, e2);

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
---
 drivers/net/ethernet/ti/davinci_mdio.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

David Lechner April 27, 2020, 3:16 p.m. UTC | #1
On 4/27/20 4:40 AM, Wei Yongjun wrote:
> platform_get_resource() may fail and return NULL, so we should
> better check it's return value to avoid a NULL pointer dereference
> a bit later in the code.
> 
> This is detected by Coccinelle semantic patch.
> 
> @@
> expression pdev, res, n, t, e, e1, e2;
> @@
> 
> res = \(platform_get_resource\|platform_get_resource_byname\)(pdev, t, n);
> + if (!res)
> +   return -EINVAL;
> ... when != res == NULL
> e = devm_ioremap(e1, res->start, e2);
> 
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
> ---
>   drivers/net/ethernet/ti/davinci_mdio.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c
> index 38b7f6d35759..702fdc393da0 100644
> --- a/drivers/net/ethernet/ti/davinci_mdio.c
> +++ b/drivers/net/ethernet/ti/davinci_mdio.c
> @@ -397,6 +397,8 @@ static int davinci_mdio_probe(struct platform_device *pdev)
>   	data->dev = dev;
>   
>   	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res)
> +		return -EINVAL;
>   	data->regs = devm_ioremap(dev, res->start, resource_size(res));
>   	if (!data->regs)
>   		return -ENOMEM;
> 

Could we use devm_platform_ioremap_resource() instead?
diff mbox series

Patch

diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c
index 38b7f6d35759..702fdc393da0 100644
--- a/drivers/net/ethernet/ti/davinci_mdio.c
+++ b/drivers/net/ethernet/ti/davinci_mdio.c
@@ -397,6 +397,8 @@  static int davinci_mdio_probe(struct platform_device *pdev)
 	data->dev = dev;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -EINVAL;
 	data->regs = devm_ioremap(dev, res->start, resource_size(res));
 	if (!data->regs)
 		return -ENOMEM;