Re: [PATCH] Fix buffer overrun in HID-SENSOR name.

From: srinivas pandruvada
Date: Mon Mar 13 2023 - 12:56:30 EST


On Fri, 2023-03-10 at 15:54 -0800, Todd Brandt wrote:
> Philipp Jungkamp created this fix, I'm simply submitting it. I've
> verified it fixes bugzilla issue 217169.
>
Not the correct change log. Something like below:

On some platforms there are some platform device is created with
invalid name. For example:
"HID-SENSOR-INT-020b?.39.auto" instead of "HID-SENSOR-INT-020b.39.auto"

This string include some invalid character, hence it will fail to
properly load the driver which will handle this custom sensor. Also
it is a problem for some user space tools, which parses the device
names.

This is because the string real_usage is not NULL terminated and
printed with %s to form device name.

To address this initialize the real_usage string with 0s.

> Reported-and-tested-by: Todd Brandt <todd.e.brandt@xxxxxxxxxxxxxxx>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217169



Fixes: 98c062e82451 ("HID: hid-sensor-custom: Allow more custom iio
sensors")

Suggest-by: Philipp Jungkamp p.jungkamp@xxxxxxx

> Signed-off-by: Todd Brandt <todd.e.brandt@xxxxxxxxx>

Thanks,
Srinivas

> ---
>  drivers/hid/hid-sensor-custom.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/hid/hid-sensor-custom.c b/drivers/hid/hid-
> sensor-custom.c
> index 3e3f89e01d81..d85398721659 100644
> --- a/drivers/hid/hid-sensor-custom.c
> +++ b/drivers/hid/hid-sensor-custom.c
> @@ -940,7 +940,7 @@ hid_sensor_register_platform_device(struct
> platform_device *pdev,
>                                     struct hid_sensor_hub_device
> *hsdev,
>                                     const struct
> hid_sensor_custom_match *match)
>  {
> -       char real_usage[HID_SENSOR_USAGE_LENGTH];
> +       char real_usage[HID_SENSOR_USAGE_LENGTH] = { 0 };
>         struct platform_device *custom_pdev;
>         const char *dev_name;
>         char *c;