Re: [PATCH] pinctrl: ns2: Fix potential NULL dereference

From: Ray Jui
Date: Thu May 30 2019 - 20:21:15 EST




On 5/28/2019 7:43 PM, Young Xiao 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.
>
> Signed-off-by: Young Xiao <92siuyang@xxxxxxxxx>
> ---
> drivers/pinctrl/bcm/pinctrl-ns2-mux.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/pinctrl/bcm/pinctrl-ns2-mux.c b/drivers/pinctrl/bcm/pinctrl-ns2-mux.c
> index 4b5cf0e..2bf6af7 100644
> --- a/drivers/pinctrl/bcm/pinctrl-ns2-mux.c
> +++ b/drivers/pinctrl/bcm/pinctrl-ns2-mux.c
> @@ -1048,6 +1048,8 @@ static int ns2_pinmux_probe(struct platform_device *pdev)
> return PTR_ERR(pinctrl->base0);
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> + if (!res)
> + return -EINVAL;

Right, usually not needed if devm_ioremap_resource is used since it was
checked there. But in this case, I do think it needs to be checked. This
change looks good to me. Thanks.

> pinctrl->base1 = devm_ioremap_nocache(&pdev->dev, res->start,
> resource_size(res));
> if (!pinctrl->base1) {
>

Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx>