Re: [PATCH] ACPICA: add more parameter validation for acpi_walk_namespace()

["Rafael J. Wysocki" <rafael@kernel.org>]

On Fri, Aug 15, 2025 at 10:56 AM Cryolitia PukNgae via B4 Relay
<devnull+cryolitia.uniontech.com@kernel.org> wrote:
>
> From: Cryolitia PukNgae <cryolitia@uniontech.com>
>
> On the Honor FMB-P-PCB laptop, an incorrect ACPI table causes
> sdw_intel_acpi_scan to pass a NULL pointer as start_object to
> acpi_walk_namespace() when calling it, which eventually causes the
> kernel to report a NULL pointer dereference[1].
>
> 1. https://gist.github.com/Cryolitia/a860ffc97437dcd2cd988371d5b73ed7
>
> Signed-off-by: Cryolitia PukNgae <cryolitia@uniontech.com>

Please submit ACPICA changes to the upstream ACPICA project on GitHub
as pull requests.  Once they have been merged upstream, you can submit
a Linux patch based on the upstream one with a pointer to the
corresponding upstream commit.

Thanks!

> ---
>  drivers/acpi/acpica/nsxfeval.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/acpica/nsxfeval.c b/drivers/acpi/acpica/nsxfeval.c
> index f9d059647cc52e94ce013af3382addba338820e8..c1f318ea7d5fcd846dc158b155286a6f5bba4cff 100644
> --- a/drivers/acpi/acpica/nsxfeval.c
> +++ b/drivers/acpi/acpica/nsxfeval.c
> @@ -564,7 +564,7 @@ acpi_walk_namespace(acpi_object_type type,
>
>         /* Parameter validation */
>
> -       if ((type > ACPI_TYPE_LOCAL_MAX) ||
> +       if ((type > ACPI_TYPE_LOCAL_MAX) || (start_object == NULL) ||
>             (!max_depth) || (!descending_callback && !ascending_callback)) {
>                 return_ACPI_STATUS(AE_BAD_PARAMETER);
>         }
>
> ---
> base-commit: 24ea63ea387714634813359e2c8e0e6c36952f73
> change-id: 20250815-acpi_fix-3724e6c4da02
>
> Best regards,
> --
> Cryolitia PukNgae <cryolitia@uniontech.com>
>
>