2023-05-13 12:34:04

by Krzysztof Kozlowski

Subject: [PATCH] pinctrl: qcom: sc8180x: gracefully handle missing IO memory resource

If device was probed with incorrect DT or ACPI tables, the IO memory
resource would be missing and driver would derefernce NULL pointer in
sc8180x_pinctrl_add_tile_resources(). Add simplep check if IO memory
resource was provided to silence Smatch warning:

drivers/pinctrl/qcom/pinctrl-sc8180x.c:1664 sc8180x_pinctrl_add_tile_resources() error: potentially dereferencing uninitialized 'mres'.

Signed-off-by: Krzysztof Kozlowski <[email protected]>
---
drivers/pinctrl/qcom/pinctrl-sc8180x.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/pinctrl/qcom/pinctrl-sc8180x.c b/drivers/pinctrl/qcom/pinctrl-sc8180x.c
index 704a99d2f93c..2fabec096aae 100644
--- a/drivers/pinctrl/qcom/pinctrl-sc8180x.c
+++ b/drivers/pinctrl/qcom/pinctrl-sc8180x.c
@@ -1630,7 +1630,8 @@ static const struct msm_pinctrl_soc_data sc8180x_acpi_pinctrl = {
static int sc8180x_pinctrl_add_tile_resources(struct platform_device *pdev)
{
int nres_num = pdev->num_resources + ARRAY_SIZE(sc8180x_tiles) - 1;
- struct resource *mres, *nres, *res;
+ struct resource *mres = NULL;
+ struct resource *nres, *res;
int i, ret;

/*
@@ -1657,6 +1658,9 @@ static int sc8180x_pinctrl_add_tile_resources(struct platform_device *pdev)
*res++ = *r;
}

+ if (!mres)
+ return -EINVAL;
+
/* Append tile memory resources */
for (i = 0; i < ARRAY_SIZE(sc8180x_tiles); i++, res++) {
const struct tile_info *info = &sc8180x_tile_info[i];
--
2.34.1

2023-05-15 01:47:10

by Bjorn Andersson

Subject: Re: [PATCH] pinctrl: qcom: sc8180x: gracefully handle missing IO memory resource

On Sat, May 13, 2023 at 01:35:10PM +0200, Krzysztof Kozlowski wrote:
> If device was probed with incorrect DT or ACPI tables, the IO memory
> resource would be missing and driver would derefernce NULL pointer in
> sc8180x_pinctrl_add_tile_resources(). Add simplep check if IO memory
> resource was provided to silence Smatch warning:
>
> drivers/pinctrl/qcom/pinctrl-sc8180x.c:1664 sc8180x_pinctrl_add_tile_resources() error: potentially dereferencing uninitialized 'mres'.
>
> Signed-off-by: Krzysztof Kozlowski <[email protected]>

Reviewed-by: Bjorn Andersson <[email protected]>

> ---
> drivers/pinctrl/qcom/pinctrl-sc8180x.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pinctrl/qcom/pinctrl-sc8180x.c b/drivers/pinctrl/qcom/pinctrl-sc8180x.c
> index 704a99d2f93c..2fabec096aae 100644
> --- a/drivers/pinctrl/qcom/pinctrl-sc8180x.c
> +++ b/drivers/pinctrl/qcom/pinctrl-sc8180x.c
> @@ -1630,7 +1630,8 @@ static const struct msm_pinctrl_soc_data sc8180x_acpi_pinctrl = {
> static int sc8180x_pinctrl_add_tile_resources(struct platform_device *pdev)
> {
> int nres_num = pdev->num_resources + ARRAY_SIZE(sc8180x_tiles) - 1;
> - struct resource *mres, *nres, *res;
> + struct resource *mres = NULL;
> + struct resource *nres, *res;
> int i, ret;
>
> /*
> @@ -1657,6 +1658,9 @@ static int sc8180x_pinctrl_add_tile_resources(struct platform_device *pdev)
> *res++ = *r;
> }
>
> + if (!mres)
> + return -EINVAL;
> +
> /* Append tile memory resources */
> for (i = 0; i < ARRAY_SIZE(sc8180x_tiles); i++, res++) {
> const struct tile_info *info = &sc8180x_tile_info[i];
> --
> 2.34.1
>

2023-05-16 14:00:42

by Linus Walleij

Subject: Re: [PATCH] pinctrl: qcom: sc8180x: gracefully handle missing IO memory resource

On Sat, May 13, 2023 at 1:35 PM Krzysztof Kozlowski
<[email protected]> wrote:

> If device was probed with incorrect DT or ACPI tables, the IO memory
> resource would be missing and driver would derefernce NULL pointer in
> sc8180x_pinctrl_add_tile_resources(). Add simplep check if IO memory
> resource was provided to silence Smatch warning:
>
> drivers/pinctrl/qcom/pinctrl-sc8180x.c:1664 sc8180x_pinctrl_add_tile_resources() error: potentially dereferencing uninitialized 'mres'.
>
> Signed-off-by: Krzysztof Kozlowski <[email protected]>

Patch applied as non-urgent fix.

Yours,
Linus Walleij