CVE-2025-71101

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

platform/x86: hp-bioscfg: Fix out-of-bounds array access in ACPI package parsing

The hp_populate_*_elements_from_package() functions in the hp-bioscfg driver contain out-of-bounds array access vulnerabilities.

These functions parse ACPI packages into internal data structures using a for loop with index variable elem that iterates through enum_obj/integer_obj/order_obj/password_obj/string_obj arrays.

When processing multi-element fields like PREREQUISITES and ENUM_POSSIBLE_VALUES, these functions read multiple consecutive array elements using expressions like enum_obj[elem + reqs] and enum_obj[elem + pos_values] within nested loops.

The bug is that the bounds check only validated elem, but did not consider the additional offset when accessing elem + reqs or elem + pos_values.

The fix changes the bounds check to validate the actual accessed index.

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Potential Mitigations

• Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
• When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
• Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
• To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/540.html

References

• https://git.kernel.org/stable/c/79cab730dbaaac03b946c7f5681bd08c986e2abd
• https://git.kernel.org/stable/c/cf7ae870560b988247a4bbbe5399edd326632680
• https://git.kernel.org/stable/c/db4c26adf7117b1a4431d1197ae7109fee3230ad
• https://git.kernel.org/stable/c/e44c42c830b7ab36e3a3a86321c619f24def5206