Re: [PATCH v1] drivers/acpi/processor_idle: check the return value of acpi_fetch_acpi_dev()

From: Rafael J. Wysocki
Date: Sat Sep 10 2022 - 12:11:07 EST


On Sun, Aug 28, 2022 at 10:54 PM Li Zhong <floridsleeves@xxxxxxxxx> wrote:
>
> The return value of acpi_fetch_acpi_dev() could be NULL, which will
> cause null pointer dereference if used in acpi_device_hid().
>
> Signed-off-by: Li Zhong <floridsleeves@xxxxxxxxx>
> ---
> drivers/acpi/processor_idle.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
> index 16a1663d02d4..519f8f741da3 100644
> --- a/drivers/acpi/processor_idle.c
> +++ b/drivers/acpi/processor_idle.c
> @@ -1117,6 +1117,8 @@ static int acpi_processor_get_lpi_info(struct acpi_processor *pr)
> status = acpi_get_parent(handle, &pr_ahandle);
> while (ACPI_SUCCESS(status)) {
> d = acpi_fetch_acpi_dev(pr_ahandle);
> + if (!d)
> + break;
> handle = pr_ahandle;
>
> if (strcmp(acpi_device_hid(d), ACPI_PROCESSOR_CONTAINER_HID))
> --

Applied (with some edits in the subject and changelog) as 6.1 material, thanks!