CVE-2023-53856

/// Technical description

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

of: overlay: Call of_changeset_init() early

When of_overlay_fdt_apply() fails, the changeset may be partially

applied, and the caller is still expected to call of_overlay_remove() to

clean up this partial state.

However, of_overlay_apply() calls of_resolve_phandles() before

init_overlay_changeset(). Hence if the overlay fails to apply due to an

unresolved symbol, the overlay_changeset.cset.entries list is still

uninitialized, and cleanup will crash with a NULL-pointer dereference in

overlay_removal_is_ok().

Fix this by moving the call to of_changeset_init() from

init_overlay_changeset() to of_overlay_fdt_apply(), where all other

early initialization is done.

/// 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