[PATCH v5 0/4] platform/x86: hp-bioscfg: fix ACPI package handling on HP EliteBook 840 G2

[PATCH v5 0/4] platform/x86: hp-bioscfg: fix ACPI package handling on HP EliteBook 840 G2

[Muhammad Bilal]

This series fixes attribute enumeration failures on the HP EliteBook 840
G2 (BIOS M71 Ver. 01.31), whose BIOS returns shorter ACPI WMI packages
than hp_init_bios_package_attribute() currently accepts, plus occasional
type-mismatched elements after a failed WMI query.

Patches 1 and 2 are prerequisites: they make each per-type parser bound
itself on the real, validated package count instead of an incorrect value
derived from the NAME string's length. Both are no-ops today, since
every package the driver currently handles already meets the old
minimum size. They matter because patch 3 depends on them: once the
minimum size check is relaxed, the elements array can genuinely be
smaller than a parser's fixed per-type count, and without patches 1 and
2 this would result in an out-of-bounds heap read.

Patch 3 relaxes that minimum size check to accept packages missing
optional type-specific fields, as long as the common fields (NAME
through SECURITY_LEVEL) are present.

Patch 4 changes a type mismatch on one element from aborting the whole
attribute to warning and skipping the offending element, matching the
existing handling of unsupported element types.

Patches 1 through 3 are intended to be applied together, as patch 3
depends on the preparatory fixes in patches 1 and 2.

v4: https://lore.kernel.org/all/20260708154846.12356-1-meatuni001@gmail.com/

Changes since v4:
- Patch 1: added missing kerneldoc @foo_count entries for the five new
  parameters. (Ilpo)
- No other code changes.

Changes since v3:
- Patch 1: dropped the Fixes: tag (the patch does not fix anything on
  its own; Cc: stable is enough for stable to pull it in as a series
  dependency) and reworded the forward reference from "a later patch"
  to "an upcoming change". (Ilpo)
- Patch 2: dropped the Fixes: tag and reworded the forward reference as
  in patch 1, plus dropped the redundant sentence describing the
  out-of-bounds read. (Ilpo)
- No code changes; commit-message wording only.

Changes since v2:
- Split the single "pass validated count and bound ordered list
  parsing" patch into two: patch 1 fixes the count value passed to
  each wrapper, patch 2 adds the missing elem < count bound to the
  ordered list parser. (Ilpo)
- Rewrote patch 1's commit message to lead with the bug instead of
  quoting code, and to state up front that a later patch depends on
  it. (Ilpo)
- Reworded "thread the count down" and "guess at it" phrasing. (Ilpo)

Muhammad Bilal (4):
  platform/x86: hp-bioscfg: pass validated element count to package
    parsers
  platform/x86: hp-bioscfg: bound ordered-list parsing by the package
    count
  platform/x86: hp-bioscfg: accept reduced ACPI packages from older HP
    BIOS
  platform/x86: hp-bioscfg: warn on element type mismatch instead of
    failing

 drivers/platform/x86/hp/hp-bioscfg/bioscfg.c     | 16 +++++++++++++---
 drivers/platform/x86/hp/hp-bioscfg/bioscfg.h     |  8 ++++++++
 .../platform/x86/hp/hp-bioscfg/enum-attributes.c | 11 +++++++----
 .../platform/x86/hp/hp-bioscfg/int-attributes.c  |  4 +++-
 .../x86/hp/hp-bioscfg/order-list-attributes.c    |  8 +++++---
 .../x86/hp/hp-bioscfg/passwdobj-attributes.c     |  6 ++++--
 .../x86/hp/hp-bioscfg/string-attributes.c        |  4 +++-
 7 files changed, 43 insertions(+), 14 deletions(-)

-- 
2.55.0

[PATCH v5 1/4] platform/x86: hp-bioscfg: pass validated element count to package parsers

[Muhammad Bilal]

The per-type package parsers are handed the wrong element count.

hp_init_bios_package_attribute() validates obj->package.count and then
calls one of the five hp_populate_*_package_data() wrappers (string,
integer, enumeration, ordered list, password). Each wrapper forwards a
count to its hp_populate_*_elements_from_package() parser, but instead
of forwarding the validated obj->package.count it derives the count
from elements[0]. elements[0] is the NAME field and is always an
ACPI_TYPE_STRING, so reading ->package.count from it in fact reads
->string.length through the union acpi_object. The parsers thus bound
themselves against the length of the name string rather than against
the real number of elements in the package.

This is safe today because hp_init_bios_package_attribute() refuses any
package that has fewer than the type's element count, so a parser only
ever runs on a full package and never reads past it regardless of the
bogus bound.

An upcoming change relaxes that check to accept shorter packages. Once
a parser can receive fewer elements than its per-type count, a bound
taken from the name length no longer reflects the array size, and the
"elem < count" loop conditions and "elem + n >= count" sub-loop guards
read past the end of elements[] - an out-of-bounds heap read.

Forward the validated obj->package.count to every *_package_data()
wrapper so the parsers bound themselves against the real package size.
This does not change behaviour for the packages that enumerate
correctly today and is a prerequisite for accepting shorter packages
safely.

Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
---
 drivers/platform/x86/hp/hp-bioscfg/bioscfg.c               | 5 +++++
 drivers/platform/x86/hp/hp-bioscfg/bioscfg.h               | 5 +++++
 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c       | 4 +++-
 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c        | 4 +++-
 drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c | 6 ++++--
 drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c  | 6 ++++--
 drivers/platform/x86/hp/hp-bioscfg/string-attributes.c     | 4 +++-
 7 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
index 27fd6cd215290..768330d291da8 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.c
@@ -731,26 +731,31 @@ static int hp_init_bios_package_attribute(enum hp_wmi_data_type attr_type,
 	switch (attr_type) {
 	case HPWMI_STRING_TYPE:
 		ret = hp_populate_string_package_data(elements,
+						      obj->package.count,
 						      instance_id,
 						      attr_name_kobj);
 		break;
 	case HPWMI_INTEGER_TYPE:
 		ret = hp_populate_integer_package_data(elements,
+						       obj->package.count,
 						       instance_id,
 						       attr_name_kobj);
 		break;
 	case HPWMI_ENUMERATION_TYPE:
 		ret = hp_populate_enumeration_package_data(elements,
+							   obj->package.count,
 							   instance_id,
 							   attr_name_kobj);
 		break;
 	case HPWMI_ORDERED_LIST_TYPE:
 		ret = hp_populate_ordered_list_package_data(elements,
+							    obj->package.count,
 							    instance_id,
 							    attr_name_kobj);
 		break;
 	case HPWMI_PASSWORD_TYPE:
 		ret = hp_populate_password_package_data(elements,
+							obj->package.count,
 							instance_id,
 							attr_name_kobj);
 		break;
diff --git a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h
index f1eec0e4ba075..416d7e7aaaae3 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h
+++ b/drivers/platform/x86/hp/hp-bioscfg/bioscfg.h
@@ -401,6 +401,7 @@ int hp_populate_string_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
 int hp_alloc_string_data(void);
 void hp_exit_string_attributes(void);
 int hp_populate_string_package_data(union acpi_object *str_obj,
+				    int str_obj_count,
 				    int instance_id,
 				    struct kobject *attr_name_kobj);
 
@@ -411,6 +412,7 @@ int hp_populate_integer_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
 int hp_alloc_integer_data(void);
 void hp_exit_integer_attributes(void);
 int hp_populate_integer_package_data(union acpi_object *integer_obj,
+				     int integer_obj_count,
 				     int instance_id,
 				     struct kobject *attr_name_kobj);
 
@@ -421,6 +423,7 @@ int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
 int hp_alloc_enumeration_data(void);
 void hp_exit_enumeration_attributes(void);
 int hp_populate_enumeration_package_data(union acpi_object *enum_obj,
+					 int enum_obj_count,
 					 int instance_id,
 					 struct kobject *attr_name_kobj);
 
@@ -432,6 +435,7 @@ int hp_populate_ordered_list_buffer_data(u8 *buffer_ptr,
 int hp_alloc_ordered_list_data(void);
 void hp_exit_ordered_list_attributes(void);
 int hp_populate_ordered_list_package_data(union acpi_object *order_obj,
+					  int order_obj_count,
 					  int instance_id,
 					  struct kobject *attr_name_kobj);
 
@@ -440,6 +444,7 @@ int hp_populate_password_buffer_data(u8 *buffer_ptr, u32 *buffer_size,
 				     int instance_id,
 				     struct kobject *attr_name_kobj);
 int hp_populate_password_package_data(union acpi_object *password_obj,
+				      int password_obj_count,
 				      int instance_id,
 				      struct kobject *attr_name_kobj);
 int hp_alloc_password_data(void);
diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
index af4d1920d4880..de156a9f88a18 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
@@ -300,10 +300,12 @@ static int hp_populate_enumeration_elements_from_package(union acpi_object *enum
  * Populate all properties of an instance under enumeration attribute
  *
  * @enum_obj: ACPI object with enumeration data
+ * @enum_obj_count: Number of elements in @enum_obj
  * @instance_id: The instance to enumerate
  * @attr_name_kobj: The parent kernel object
  */
 int hp_populate_enumeration_package_data(union acpi_object *enum_obj,
+					 int enum_obj_count,
 					 int instance_id,
 					 struct kobject *attr_name_kobj)
 {
@@ -312,7 +314,7 @@ int hp_populate_enumeration_package_data(union acpi_object *enum_obj,
 	enum_data->attr_name_kobj = attr_name_kobj;
 
 	hp_populate_enumeration_elements_from_package(enum_obj,
-						      enum_obj->package.count,
+						      enum_obj_count,
 						      instance_id);
 	hp_update_attribute_permissions(enum_data->common.is_readonly,
 					&enumeration_current_val);
diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c
index d96e160953e39..f2fd966c9ca4c 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c
@@ -275,10 +275,12 @@ static int hp_populate_integer_elements_from_package(union acpi_object *integer_
  * Populate all properties of an instance under integer attribute
  *
  * @integer_obj: ACPI object with integer data
+ * @integer_obj_count: Number of elements in @integer_obj
  * @instance_id: The instance to enumerate
  * @attr_name_kobj: The parent kernel object
  */
 int hp_populate_integer_package_data(union acpi_object *integer_obj,
+				     int integer_obj_count,
 				     int instance_id,
 				     struct kobject *attr_name_kobj)
 {
@@ -286,7 +288,7 @@ int hp_populate_integer_package_data(union acpi_object *integer_obj,
 
 	integer_data->attr_name_kobj = attr_name_kobj;
 	hp_populate_integer_elements_from_package(integer_obj,
-						  integer_obj->package.count,
+						  integer_obj_count,
 						  instance_id);
 	hp_update_attribute_permissions(integer_data->common.is_readonly,
 					&integer_current_val);
diff --git a/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
index f09489a085c86..cc5bebe73a93b 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
@@ -298,10 +298,12 @@ static int hp_populate_ordered_list_elements_from_package(union acpi_object *ord
  * Populate all properties of an instance under ordered_list attribute
  *
  * @order_obj: ACPI object with ordered_list data
+ * @order_obj_count: Number of elements in @order_obj
  * @instance_id: The instance to enumerate
  * @attr_name_kobj: The parent kernel object
  */
-int hp_populate_ordered_list_package_data(union acpi_object *order_obj, int instance_id,
+int hp_populate_ordered_list_package_data(union acpi_object *order_obj, int order_obj_count,
+					  int instance_id,
 					  struct kobject *attr_name_kobj)
 {
 	struct ordered_list_data *ordered_list_data = &bioscfg_drv.ordered_list_data[instance_id];
@@ -309,7 +311,7 @@ int hp_populate_ordered_list_package_data(union acpi_object *order_obj, int inst
 	ordered_list_data->attr_name_kobj = attr_name_kobj;
 
 	hp_populate_ordered_list_elements_from_package(order_obj,
-						       order_obj->package.count,
+						       order_obj_count,
 						       instance_id);
 	hp_update_attribute_permissions(ordered_list_data->common.is_readonly,
 					&ordered_list_current_val);
diff --git a/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c
index 4d79eb8056a5d..ed5e2080f22bd 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c
@@ -385,10 +385,12 @@ static int hp_populate_password_elements_from_package(union acpi_object *passwor
  *	Populate all properties for an instance under password attribute
  *
  * @password_obj: ACPI object with password data
+ * @password_obj_count: Number of elements in @password_obj
  * @instance_id: The instance to enumerate
  * @attr_name_kobj: The parent kernel object
  */
-int hp_populate_password_package_data(union acpi_object *password_obj, int instance_id,
+int hp_populate_password_package_data(union acpi_object *password_obj, int password_obj_count,
+				      int instance_id,
 				      struct kobject *attr_name_kobj)
 {
 	struct password_data *password_data = &bioscfg_drv.password_data[instance_id];
@@ -396,7 +398,7 @@ int hp_populate_password_package_data(union acpi_object *password_obj, int insta
 	password_data->attr_name_kobj = attr_name_kobj;
 
 	hp_populate_password_elements_from_package(password_obj,
-						   password_obj->package.count,
+						   password_obj_count,
 						   instance_id);
 
 	hp_friendly_user_name_update(password_data->common.path,
diff --git a/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c
index fe5a9a3a4ef17..f98c32dacbc74 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c
@@ -263,10 +263,12 @@ static int hp_populate_string_elements_from_package(union acpi_object *string_ob
  * Populate all properties of an instance under string attribute
  *
  * @string_obj: ACPI object with string data
+ * @string_obj_count: Number of elements in @string_obj
  * @instance_id: The instance to enumerate
  * @attr_name_kobj: The parent kernel object
  */
 int hp_populate_string_package_data(union acpi_object *string_obj,
+				    int string_obj_count,
 				    int instance_id,
 				    struct kobject *attr_name_kobj)
 {
@@ -275,7 +277,7 @@ int hp_populate_string_package_data(union acpi_object *string_obj,
 	string_data->attr_name_kobj = attr_name_kobj;
 
 	hp_populate_string_elements_from_package(string_obj,
-						 string_obj->package.count,
+						 string_obj_count,
 						 instance_id);
 
 	hp_update_attribute_permissions(string_data->common.is_readonly,
-- 
2.55.0

[PATCH v5 2/4] platform/x86: hp-bioscfg: bound ordered-list parsing by the package count

[Muhammad Bilal]

hp_populate_ordered_list_elements_from_package() differs from the other
per-type parsers: its main loop is bounded only by the fixed per-type
count and never checks elem against the number of elements actually
present in the package,

  for (elem = 1, eloc = 1; eloc < ORD_ELEM_CNT; elem++, eloc++)

whereas the string, integer, enumeration and password parsers bound
their main loop with "elem < count" as well.

This is safe today because hp_init_bios_package_attribute() rejects any
package with fewer than ORD_ELEM_CNT elements before the parser runs.
An upcoming change, however, relaxes that check to accept shorter
packages.

Bound the loop by the validated element count as well, so it stops at
whichever comes first, the per-type count or the real package size,

  for (elem = 1, eloc = 1; eloc < ORD_ELEM_CNT && elem < order_obj_count;
       elem++, eloc++)

order_obj_count is the validated element count, now correctly forwarded
from the caller. No functional change for packages that enumerate
correctly today.

Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
---
 drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
index cc5bebe73a93b..863e486474ad0 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
@@ -145,7 +145,7 @@ static int hp_populate_ordered_list_elements_from_package(union acpi_object *ord
 	if (!order_obj)
 		return -EINVAL;
 
-	for (elem = 1, eloc = 1; eloc < ORD_ELEM_CNT; elem++, eloc++) {
+	for (elem = 1, eloc = 1; eloc < ORD_ELEM_CNT && elem < order_obj_count; elem++, eloc++) {
 
 		switch (order_obj[elem].type) {
 		case ACPI_TYPE_STRING:
-- 
2.55.0

[PATCH v5 3/4] platform/x86: hp-bioscfg: accept reduced ACPI packages from older HP BIOS

[Muhammad Bilal]

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 <meatuni001@gmail.com>
---
 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 768330d291da8..78019644ec358 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 416d7e7aaaae3..ac57d6eab4c35 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)						\
-- 
2.55.0

[PATCH v5 4/4] platform/x86: hp-bioscfg: warn on element type mismatch instead of failing

[Muhammad Bilal]

hp_populate_enumeration_elements_from_package() returns -EIO and aborts
enumeration of the entire attribute when any single element has an
unexpected ACPI type. This is observed on HP EliteBook 840 G2 when the
BIOS returns malformed ACPI data following a failed WMI query:

  ACPI BIOS Error (bug): AE_AML_BUFFER_LIMIT, Index (0x000000032)
    is beyond end of object (length 0x32)
  ACPI Error: Aborting method \_SB.WMID.WQBE due to previous error
  Error expected type 2 for elem 13, but got type 1 instead
  hp_bioscfg: Returned error 0x3,
    "Invalid command value/Feature not supported"

Aborting immediately discards the attribute entirely.

Warn about the unexpected element type, free the temporary string, skip
the offending element, and continue parsing the remaining package
instead of failing the whole attribute.

Fixes: a34fc329b189 ("platform/x86: hp-bioscfg: bioscfg")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
---
 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
index de156a9f88a18..21077d17113b9 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
@@ -163,10 +163,11 @@ static int hp_populate_enumeration_elements_from_package(union acpi_object *enum
 
 		/* Check that both expected and read object type match */
 		if (expected_enum_types[eloc] != enum_obj[elem].type) {
-			pr_err("Error expected type %d for elem %d, but got type %d instead\n",
-			       expected_enum_types[eloc], elem, enum_obj[elem].type);
+			pr_warn("Unexpected element type at elem %d: expected %d, got %d, skipping\n",
+				elem, expected_enum_types[eloc], enum_obj[elem].type);
 			kfree(str_value);
-			return -EIO;
+			str_value = NULL;
+			continue;
 		}
 
 		/* Assign appropriate element value to corresponding field */
-- 
2.55.0

Re: [PATCH v5 0/4] platform/x86: hp-bioscfg: fix ACPI package handling on HP EliteBook 840 G2

[Ilpo Järvinen]

On Thu, 09 Jul 2026 21:58:55 +0500, Muhammad Bilal wrote:

> This series fixes attribute enumeration failures on the HP EliteBook 840
> G2 (BIOS M71 Ver. 01.31), whose BIOS returns shorter ACPI WMI packages
> than hp_init_bios_package_attribute() currently accepts, plus occasional
> type-mismatched elements after a failed WMI query.
> 
> Patches 1 and 2 are prerequisites: they make each per-type parser bound
> itself on the real, validated package count instead of an incorrect value
> derived from the NAME string's length. Both are no-ops today, since
> every package the driver currently handles already meets the old
> minimum size. They matter because patch 3 depends on them: once the
> minimum size check is relaxed, the elements array can genuinely be
> smaller than a parser's fixed per-type count, and without patches 1 and
> 2 this would result in an out-of-bounds heap read.
> 
> [...]

Thank you for your contribution, it has been applied to my local
review-ilpo-next branch. Note it will show up in the public
platform-drivers-x86/review-ilpo-next branch only once I've pushed my
local branch there, which might take a while.

FYI [if applicable to your patch], as per Linus' policy change, also
fixes are mostly routed through for-next unless the fix is for a
commit introduced in the most recent cycle or is clearly a regression
fix.

The list of commits applied:
[1/4] platform/x86: hp-bioscfg: pass validated element count to package parsers
      commit: e0ddfd77c0c320b7d12b6c9169303b140b798775
[2/4] platform/x86: hp-bioscfg: bound ordered-list parsing by the package count
      commit: 1d143d78299d0eb4536698bf98c1815ec69f22a9
[3/4] platform/x86: hp-bioscfg: accept reduced ACPI packages from older HP BIOS
      commit: 40e10e6cc8f70c041431a1e30186807e28ec46e0
[4/4] platform/x86: hp-bioscfg: warn on element type mismatch instead of failing
      commit: b0e2af3ec94e0431adb59d9f249ebbd3b7285158

--
 i.