[PATCH] ARM: EXYNOS: Handle of of_iomap() failure

[PATCH] ARM: EXYNOS: Handle of of_iomap() failure

[Krzysztof Kozlowski]

Prevent possible NULL pointer dereference if of_iomap() fails. Handle
the error by skipping such power domain.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
---
 arch/arm/mach-exynos/pm_domains.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
index 20f267121b3e..fd7640a6b503 100644
--- a/arch/arm/mach-exynos/pm_domains.c
+++ b/arch/arm/mach-exynos/pm_domains.c
@@ -128,6 +128,13 @@ static __init int exynos4_pm_init_power_domain(void)
 		pd->pd.name = kstrdup(np->name, GFP_KERNEL);
 		pd->name = pd->pd.name;
 		pd->base = of_iomap(np, 0);
+		if (!pd->base) {
+			dev_warn(&pdev->dev, "Failed to map memory\n");
+			kfree(pd);
+			of_node_put(np);
+			continue;
+		}
+
 		pd->pd.power_off = exynos_pd_power_off;
 		pd->pd.power_on = exynos_pd_power_on;
 
-- 
1.9.1

[PATCH] ARM: EXYNOS: Handle of of_iomap() failure

[Kukjin Kim]

Krzysztof Kozlowski wrote:
> 
> Prevent possible NULL pointer dereference if of_iomap() fails. Handle
> the error by skipping such power domain.
> 
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> ---
>  arch/arm/mach-exynos/pm_domains.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
> index 20f267121b3e..fd7640a6b503 100644
> --- a/arch/arm/mach-exynos/pm_domains.c
> +++ b/arch/arm/mach-exynos/pm_domains.c
> @@ -128,6 +128,13 @@ static __init int exynos4_pm_init_power_domain(void)
>  		pd->pd.name = kstrdup(np->name, GFP_KERNEL);
>  		pd->name = pd->pd.name;
>  		pd->base = of_iomap(np, 0);
> +		if (!pd->base) {
> +			dev_warn(&pdev->dev, "Failed to map memory\n");
> +			kfree(pd);
> +			of_node_put(np);
> +			continue;
> +		}
> +
>  		pd->pd.power_off = exynos_pd_power_off;
>  		pd->pd.power_on = exynos_pd_power_on;
> 
> --

Looks good and applied. BTW if we need more error handling like this, how about
error handling for failing of of_find_device_by_node() something like following?

diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
index 20f2671..234f967 100644
--- a/arch/arm/mach-exynos/pm_domains.c
+++ b/arch/arm/mach-exynos/pm_domains.c
@@ -116,6 +116,10 @@ static __init int exynos4_pm_init_power_domain(void)
 		struct device *dev;

 		pdev = of_find_device_by_node(np);
+		if (!pdev) {
+			/* error handling */
+		}
+
 		dev = &pdev->dev;

 		pd = kzalloc(sizeof(*pd), GFP_KERNEL);

I mean I'm not sure how many error/exception handling is required...

Note you can see your patch in Samsung tree tonight in my time.

Thanks, Kukjin

[PATCH] ARM: EXYNOS: Handle of of_iomap() failure

[Krzysztof Kozlowski]

On wto, 2015-02-03 at 12:20 +0900, Kukjin Kim wrote:
> Krzysztof Kozlowski wrote:
> > 
> > Prevent possible NULL pointer dereference if of_iomap() fails. Handle
> > the error by skipping such power domain.
> > 
> > Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> > ---
> >  arch/arm/mach-exynos/pm_domains.c | 7 +++++++
> >  1 file changed, 7 insertions(+)
> > 
> > diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
> > index 20f267121b3e..fd7640a6b503 100644
> > --- a/arch/arm/mach-exynos/pm_domains.c
> > +++ b/arch/arm/mach-exynos/pm_domains.c
> > @@ -128,6 +128,13 @@ static __init int exynos4_pm_init_power_domain(void)
> >  		pd->pd.name = kstrdup(np->name, GFP_KERNEL);
> >  		pd->name = pd->pd.name;
> >  		pd->base = of_iomap(np, 0);
> > +		if (!pd->base) {
> > +			dev_warn(&pdev->dev, "Failed to map memory\n");
> > +			kfree(pd);
> > +			of_node_put(np);
> > +			continue;
> > +		}
> > +
> >  		pd->pd.power_off = exynos_pd_power_off;
> >  		pd->pd.power_on = exynos_pd_power_on;
> > 
> > --
> 
> Looks good and applied.

Thanks!

> BTW if we need more error handling like this, how about
> error handling for failing of of_find_device_by_node() something like following?

I'll take a look into this.

Best regards,
Krzysztof

> 
> diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
> index 20f2671..234f967 100644
> --- a/arch/arm/mach-exynos/pm_domains.c
> +++ b/arch/arm/mach-exynos/pm_domains.c
> @@ -116,6 +116,10 @@ static __init int exynos4_pm_init_power_domain(void)
>  		struct device *dev;
> 
>  		pdev = of_find_device_by_node(np);
> +		if (!pdev) {
> +			/* error handling */
> +		}
> +
>  		dev = &pdev->dev;
> 
>  		pd = kzalloc(sizeof(*pd), GFP_KERNEL);
> 
> I mean I'm not sure how many error/exception handling is required...
> 
> Note you can see your patch in Samsung tree tonight in my time.
> 
> Thanks, Kukjin