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References: <20230106235308.99999-1-d-tatianin@yandex-team.ru>
In-Reply-To: <20230106235308.99999-1-d-tatianin@yandex-team.ru>
From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Wed, 11 Jan 2023 21:14:55 +0100
Message-ID: <CAJZ5v0goj3DYEbVa5PkeFBtNNvYb0wJU_dwooWdxgEyrT8yZqQ@mail.gmail.com>
Subject: Re: [PATCH v0] ACPICA: nsrepair: handle cases without a return value correctly
To:     Daniil Tatianin <d-tatianin@yandex-team.ru>
Cc:     Robert Moore <robert.moore@intel.com>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
        Len Brown <lenb@kernel.org>, linux-acpi@vger.kernel.org,
        devel@acpica.org, linux-kernel@vger.kernel.org
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On Sat, Jan 7, 2023 at 12:54 AM Daniil Tatianin
<d-tatianin@yandex-team.ru> wrote:
>
> Previously acpi_ns_simple_repair() would crash if expected_btypes
> contained any combination of ACPI_RTYPE_NONE with a different type,
> e.g | ACPI_RTYPE_INTEGER because of slightly incorrect logic in the
> !return_object branch, which wouldn't return AE_AML_NO_RETURN_VALUE
> for such cases.
>
> Found by Linux Verification Center (linuxtesting.org) with the SVACE
> static analysis tool.
>
> Link: https://github.com/acpica/acpica/pull/811
> Fixes: 61db45ca2163 ("ACPICA: Restore code that repairs NULL package elements in return values.")
> Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
> ---
>  drivers/acpi/acpica/nsrepair.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/acpi/acpica/nsrepair.c b/drivers/acpi/acpica/nsrepair.c
> index 367fcd201f96..ec512e06a48e 100644
> --- a/drivers/acpi/acpica/nsrepair.c
> +++ b/drivers/acpi/acpica/nsrepair.c
> @@ -181,8 +181,9 @@ acpi_ns_simple_repair(struct acpi_evaluate_info *info,
>          * Try to fix if there was no return object. Warning if failed to fix.
>          */
>         if (!return_object) {
> -               if (expected_btypes && (!(expected_btypes & ACPI_RTYPE_NONE))) {
> -                       if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
> +               if (expected_btypes) {
> +                       if (!(expected_btypes & ACPI_RTYPE_NONE) &&
> +                           package_index != ACPI_NOT_PACKAGE_ELEMENT) {
>                                 ACPI_WARN_PREDEFINED((AE_INFO,
>                                                       info->full_pathname,
>                                                       ACPI_WARN_ALWAYS,
> @@ -196,14 +197,15 @@ acpi_ns_simple_repair(struct acpi_evaluate_info *info,
>                                 if (ACPI_SUCCESS(status)) {
>                                         return (AE_OK); /* Repair was successful */
>                                 }
> -                       } else {
> +                       }
> +
> +                       if (expected_btypes != ACPI_RTYPE_NONE) {
>                                 ACPI_WARN_PREDEFINED((AE_INFO,
>                                                       info->full_pathname,
>                                                       ACPI_WARN_ALWAYS,
>                                                       "Missing expected return value"));
> +                               return (AE_AML_NO_RETURN_VALUE);
>                         }
> -
> -                       return (AE_AML_NO_RETURN_VALUE);
>                 }
>         }
>
> --

Applied as 6.3 material, thanks!