From 40e10e6cc8f70c041431a1e30186807e28ec46e0 Mon Sep 17 00:00:00 2001 From: Muhammad Bilal Date: Thu, 9 Jul 2026 21:58:58 +0500 Subject: [PATCH] platform/x86: hp-bioscfg: accept reduced ACPI packages from older HP BIOS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit hp_init_bios_package_attribute() hard-fails when a WMI ACPI package contains fewer elements than the type-specific expected count (e.g. 11 elements instead of 13 for INTEGER or ENUMERATION attributes). This causes the entire hp_bioscfg driver to skip attribute enumeration on older HP hardware whose BIOS returns shortened packages when optional fields like prerequisites or possible values are absent. Observed on HP EliteBook 840 G2 (BIOS M71 Ver. 01.31): hp_bioscfg: ACPI-package does not have enough elements: 11 < 13 The element layout has two tiers: - Elements 0-9 (SECURITY_LEVEL+1 = 10): common to all attribute types - Elements 10-N: type-specific (bounds, values, encodings, ...) The per-type populate functions (hp_populate_*_elements_from_package) already handle sparse packages correctly via their own elem < count loop guards and inner-loop bounds checks. The only unsafe case is when we lack even the common elements needed to register the attribute. Fix by introducing COMMON_ELEM_CNT to mark the hard minimum (10), and splitting the check into two tiers: - Fewer than COMMON_ELEM_CNT elements: hard fail, can't proceed. - Fewer than expected type-specific elements: warn, but let the populate function parse what is available. Fixes: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg") Cc: stable@vger.kernel.org Signed-off-by: Muhammad Bilal Reviewed-by: Mario Limonciello (AMD) Link: https://patch.msgid.link/20260709165900.30615-4-meatuni001@gmail.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- drivers/platform/x86/hp/hp-bioscfg/bioscfg.c | 11 ++++++++--- drivers/platform/x86/hp/hp-bioscfg/bioscfg.h | 3 +++ 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c index 768330d291da..78019644ec35 100644 --- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c @@ -661,12 +661,17 @@ static int hp_init_bios_package_attribute(enum hp_wmi_data_type attr_type, int ret = 0; /* Take action appropriate to each ACPI TYPE */ - if (obj->package.count < min_elements) { - pr_err("ACPI-package does not have enough elements: %d < %d\n", - obj->package.count, min_elements); + if (obj->package.count < COMMON_ELEM_CNT) { + pr_err("ACPI-package is missing common elements: %d < %d\n", + obj->package.count, COMMON_ELEM_CNT); goto pack_attr_exit; } + if (obj->package.count < min_elements) { + pr_warn("ACPI-package has fewer elements than expected: %d < %d, parsing available elements\n", + obj->package.count, min_elements); + } + elements = obj->package.elements; /* sanity checking */ diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h index 416d7e7aaaae..ac57d6eab4c3 100644 --- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h +++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h @@ -279,6 +279,9 @@ enum hp_wmi_data_elements { PSWD_ENCODINGS = 13, PSWD_IS_SET = 14, PSWD_ELEM_CNT = 15, + + /* Minimum elements shared by all attribute types (NAME..SECURITY_LEVEL) */ + COMMON_ELEM_CNT = SECURITY_LEVEL + 1, }; #define GET_INSTANCE_ID(type) \