CVE-2024-39488

/// Technical description

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

arm64: asm-bug: Add .align 2 to the end of __BUG_ENTRY

When CONFIG_DEBUG_BUGVERBOSE=n, we fail to add necessary padding bytes

to bug_table entries, and as a result the last entry in a bug table will

be ignored, potentially leading to an unexpected panic(). All prior

entries in the table will be handled correctly.

The arm64 ABI requires that struct fields of up to 8 bytes are

naturally-aligned, with padding added within a struct such that struct

are suitably aligned within arrays.

When CONFIG_DEBUG_BUGVERPOSE=y, the layout of a bug_entry is:

struct bug_entry {

signed int bug_addr_disp; // 4 bytes

signed int file_disp; // 4 bytes

unsigned short line; // 2 bytes

unsigned short flags; // 2 bytes

}

... with 12 bytes total, requiring 4-byte alignment.

When CONFIG_DEBUG_BUGVERBOSE=n, the layout of a bug_entry is:

struct bug_entry {

signed int bug_addr_disp; // 4 bytes

unsigned short

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References