linux-kernel - Re: [PATCH v1] drivers/acpi/processor_idle: check the return value of acpi_fetch_acpi

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAJZ5v0jrQwBh3ToZc-7J69qDJEAZ8+wXPzqjZ+zpxB4a69W-Ng@mail.gmail.com>
Date:   Mon, 29 Aug 2022 15:56:32 +0200
From:   "Rafael J. Wysocki" <rafael@...nel.org>
To:     Li Zhong <floridsleeves@...il.com>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Len Brown <lenb@...nel.org>
Subject: Re: [PATCH v1] drivers/acpi/processor_idle: check the return value of acpi_fetch_acpi_dev()

On Sun, Aug 28, 2022 at 10:54 PM Li Zhong <floridsleeves@...il.com> wrote:
>
> The return value of acpi_fetch_acpi_dev() could be NULL, which will
> cause null pointer dereference if used in acpi_device_hid().

That's true.

> Signed-off-by: Li Zhong <floridsleeves@...il.com>
> ---
>  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;

But shouldn't this be continue?

>                 handle = pr_ahandle;
>
>                 if (strcmp(acpi_device_hid(d), ACPI_PROCESSOR_CONTAINER_HID))
> --
> 2.25.1
>