[PATCH v2 9/9] platform/x86: hp-bioscfg: advance elem past consumed array elements

[Muhammad Bilal <meatuni001@gmail.com>]

The outer parsing loop in each attribute-type parser advances "elem"
(the index into the ACPI package element array) by exactly one per
iteration, but cases that consume multi-element arrays
(PREREQUISITES, ENUM_POSSIBLE_VALUES, PSWD_ENCODINGS) read "size"
consecutive elements without adjusting "elem" for the extra entries
consumed beyond the first. The next outer iteration then re-reads a
leftover element from the array just consumed instead of the next
real property, and the type check fails on that stale element,
aborting the parse with -EIO.

This produces exactly the failure visible in dmesg on the test
hardware, on every boot:

  Error expected type 2 for elem 13, but got type 1 instead
  hp_bioscfg: Returned error 0x3, "Invalid command value/Feature not
  supported"

Fix by advancing "elem" by (size - 1) after each array-consuming
loop, so the outer loop's own "elem++" lands on the correct next
element. "eloc" is intentionally left alone: it indexes the logical
property schema, not the physical element array, and each array case
is still exactly one logical property regardless of how many physical
elements it spans.

The defect is identical across all five attribute-type parsers
(enum, integer, string, ordered-list, password), which were
copy-pasted from the same template when the driver was introduced.

Fixes: 6b2770bfd6f9 ("platform/x86: hp-bioscfg: enum-attributes")
Fixes: 6f2c06d5a467 ("platform/x86: hp-bioscfg: int-attributes")
Fixes: e6c7b3e15559 ("platform/x86: hp-bioscfg: string-attributes")
Fixes: 4b2672ec71a3 ("platform/x86: hp-bioscfg: order-list-attributes")
Fixes: 8646a3b5ee3a ("platform/x86: hp-bioscfg: passwdobj-attributes")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
---
 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c       | 4 ++++
 drivers/platform/x86/hp/hp-bioscfg/int-attributes.c        | 2 ++
 drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c | 2 ++
 drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c  | 4 ++++
 drivers/platform/x86/hp/hp-bioscfg/string-attributes.c     | 2 ++
 5 files changed, 14 insertions(+)

diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
index af4d1920d488..43beb639051e 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
@@ -227,6 +227,8 @@ static int hp_populate_enumeration_elements_from_package(union acpi_object *enum
 				kfree(str_value);
 				str_value = NULL;
 			}
+			if (size)
+				elem += size - 1;
 			break;
 
 		case SECURITY_LEVEL:
@@ -280,6 +282,8 @@ static int hp_populate_enumeration_elements_from_package(union acpi_object *enum
 				kfree(str_value);
 				str_value = NULL;
 			}
+			if (size)
+				elem += (size < MAX_VALUES_SIZE ? size : MAX_VALUES_SIZE) - 1;
 			break;
 		default:
 			pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem);
diff --git a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c
index d96e160953e3..5373af71549a 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/int-attributes.c
@@ -243,6 +243,8 @@ static int hp_populate_integer_elements_from_package(union acpi_object *integer_
 				kfree(str_value);
 				str_value = NULL;
 			}
+			if (size)
+				elem += size - 1;
 			break;
 
 		case SECURITY_LEVEL:
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 704c69c18146..6696255738ba 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/order-list-attributes.c
@@ -232,6 +232,8 @@ static int hp_populate_ordered_list_elements_from_package(union acpi_object *ord
 				kfree(str_value);
 				str_value = NULL;
 			}
+			if (size)
+				elem += size - 1;
 			break;
 
 		case SECURITY_LEVEL:
diff --git a/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c
index 6bd56d3f5bd0..9b989ef756ea 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/passwdobj-attributes.c
@@ -321,6 +321,8 @@ static int hp_populate_password_elements_from_package(union acpi_object *passwor
 				str_value = NULL;
 
 			}
+			if (size)
+				elem += size - 1;
 			break;
 		case SECURITY_LEVEL:
 			password_data->common.security_level = int_value;
@@ -367,6 +369,8 @@ static int hp_populate_password_elements_from_package(union acpi_object *passwor
 				str_value = NULL;
 
 			}
+			if (size)
+				elem += size - 1;
 			break;
 		case PSWD_IS_SET:
 			password_data->is_enabled = int_value;
diff --git a/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c
index fe5a9a3a4ef1..5abec8995911 100644
--- a/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c
+++ b/drivers/platform/x86/hp/hp-bioscfg/string-attributes.c
@@ -233,6 +233,8 @@ static int hp_populate_string_elements_from_package(union acpi_object *string_ob
 				kfree(str_value);
 				str_value = NULL;
 			}
+			if (size)
+				elem += size - 1;
 			break;
 
 		case SECURITY_LEVEL:
-- 
2.55.0