CVE-2026-81011

In the Linux kernel, the following vulnerability has been resolved:

platform/x86: hp-bioscfg: pass validated element count to package parsers

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.