Re: [PATCH V1 12/15] spmi-pmic-arb: fix a possible null pointer dereference

[kgunda]

On 2017-05-31 22:59, Stephen Boyd wrote:
> On 05/30, Kiran Gunda wrote:
> > diff --git a/drivers/spmi/spmi-pmic-arb.c 
> > b/drivers/spmi/spmi-pmic-arb.c
> > index 2afe359..412481d 100644
> > --- a/drivers/spmi/spmi-pmic-arb.c
> > +++ b/drivers/spmi/spmi-pmic-arb.c
> > @@ -1003,6 +1003,12 @@ static int spmi_pmic_arb_probe(struct 
> > platform_device *pdev)
> >  	pa->spmic = ctrl;
> >
> >  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "core");
> > +	if (!res) {
> > +		dev_err(&pdev->dev, "core resource not specified\n");
> > +		err = -EINVAL;
> > +		goto err_put_ctrl;
> > +	}
> > +
> >  	pa->core_size = resource_size(res);
> >  	if (pa->core_size <= 0x800) {
> >  		dev_err(&pdev->dev, "core_size is smaller than 0x800. Failing 
> > Probe\n");
>
> I would prefer this patch instead, so that we can piggyback on
> the error checking of the devm_ioremap_resource() code. Also, add
> a Fixes: tag please so we can backport it as needed.
Sure. We will modify as per your suggestion in the next patch.
> diff --git a/drivers/spmi/spmi-pmic-arb.c 
> b/drivers/spmi/spmi-pmic-arb.c
> index 5ec3a595dc7d..0cedbda60707 100644
> --- a/drivers/spmi/spmi-pmic-arb.c
> +++ b/drivers/spmi/spmi-pmic-arb.c
> @@ -878,12 +878,12 @@ static int spmi_pmic_arb_probe(struct
> platform_device *pdev)
>  	pa->spmic = ctrl;
>
>  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "core");
> -	pa->core_size = resource_size(res);
>  	core = devm_ioremap_resource(&ctrl->dev, res);
>  	if (IS_ERR(core)) {
>  		err = PTR_ERR(core);
>  		goto err_put_ctrl;
>  	}
> +	pa->core_size = resource_size(res);
>
>  	hw_ver = readl_relaxed(core + PMIC_ARB_VERSION);
>  	is_v1  = (hw_ver < PMIC_ARB_VERSION_V2_MIN);