2022-11-22 21:22:35

by Shuah Khan

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Subject: [PATCH] leds: leds-wm831x-status: init chip_pdata before access

wm831x_status_probe() accesses status from chip_pdata before
initializing it. Fix it.

Signed-off-by: Shuah Khan <[email protected]>
---
drivers/leds/leds-wm831x-status.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/leds/leds-wm831x-status.c b/drivers/leds/leds-wm831x-status.c
index c48b80574f02..5060c83f3b25 100644
--- a/drivers/leds/leds-wm831x-status.c
+++ b/drivers/leds/leds-wm831x-status.c
@@ -212,7 +212,7 @@ static int wm831x_status_probe(struct platform_device *pdev)
struct wm831x_status_pdata pdata;
struct wm831x_status *drvdata;
struct resource *res;
- int id = pdev->id % ARRAY_SIZE(chip_pdata->status);
+ int id;
int ret;

res = platform_get_resource(pdev, IORESOURCE_REG, 0);
@@ -229,9 +229,10 @@ static int wm831x_status_probe(struct platform_device *pdev)
drvdata->wm831x = wm831x;
drvdata->reg = res->start;

- if (dev_get_platdata(wm831x->dev))
+ if (dev_get_platdata(wm831x->dev)) {
chip_pdata = dev_get_platdata(wm831x->dev);
- else
+ id = pdev->id % ARRAY_SIZE(chip_pdata->status);
+ } else
chip_pdata = NULL;

memset(&pdata, 0, sizeof(pdata));
--
2.34.1


2022-11-22 21:41:53

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH] leds: leds-wm831x-status: init chip_pdata before access

Hi!

> wm831x_status_probe() accesses status from chip_pdata before
> initializing it. Fix it.
>
> Signed-off-by: Shuah Khan <[email protected]>

Does it? ARRAY_SIZE() will be compile-time constant, no?

What is the bug? Did you test the code?

Best regards,
Pavel


> +++ b/drivers/leds/leds-wm831x-status.c
> @@ -212,7 +212,7 @@ static int wm831x_status_probe(struct platform_device *pdev)
> struct wm831x_status_pdata pdata;
> struct wm831x_status *drvdata;
> struct resource *res;
> - int id = pdev->id % ARRAY_SIZE(chip_pdata->status);
> + int id;
> int ret;
>
> res = platform_get_resource(pdev, IORESOURCE_REG, 0);
> @@ -229,9 +229,10 @@ static int wm831x_status_probe(struct platform_device *pdev)
> drvdata->wm831x = wm831x;
> drvdata->reg = res->start;
>
> - if (dev_get_platdata(wm831x->dev))
> + if (dev_get_platdata(wm831x->dev)) {
> chip_pdata = dev_get_platdata(wm831x->dev);
> - else
> + id = pdev->id % ARRAY_SIZE(chip_pdata->status);
> + } else
> chip_pdata = NULL;
>
> memset(&pdata, 0, sizeof(pdata));

--
People of Russia, stop Putin before his war on Ukraine escalates.


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2022-11-22 22:46:37

by Shuah Khan

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Subject: Re: [PATCH] leds: leds-wm831x-status: init chip_pdata before access

On 11/22/22 14:05, Pavel Machek wrote:
> Hi!
>
>> wm831x_status_probe() accesses status from chip_pdata before
>> initializing it. Fix it.
>>
>> Signed-off-by: Shuah Khan <[email protected]>
>
> Does it? ARRAY_SIZE() will be compile-time constant, no?
>
> What is the bug? Did you test the code?
>

Is ARRAY_SIZE() safe when accessing the status chip_pdata->status?
I wasn't sure. If so, this change isn't necessary.

thanks,
-- Shuah

2022-11-22 23:18:59

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH] leds: leds-wm831x-status: init chip_pdata before access

On Tue 2022-11-22 15:39:35, Shuah Khan wrote:
> On 11/22/22 14:05, Pavel Machek wrote:
> > Hi!
> >
> > > wm831x_status_probe() accesses status from chip_pdata before
> > > initializing it. Fix it.
> > >
> > > Signed-off-by: Shuah Khan <[email protected]>
> >
> > Does it? ARRAY_SIZE() will be compile-time constant, no?
> >
> > What is the bug? Did you test the code?
> >
>
> Is ARRAY_SIZE() safe when accessing the status chip_pdata->status?
> I wasn't sure. If so, this change isn't necessary.

I think so. Feel free to quite C standard to prove me wrong :-).

Best regards,
Pavel

--
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