CVE-2025-68319

/// Technical description

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

netconsole: Acquire su_mutex before navigating configs hierarchy

There is a race between operations that iterate over the userdata

cg_children list and concurrent add/remove of userdata items through

configfs. The update_userdata() function iterates over the

nt->userdata_group.cg_children list, and count_extradata_entries() also

iterates over this same list to count nodes.

Quoting from Documentation/filesystems/configfs.rst:

> A subsystem can navigate the cg_children list and the ci_parent pointer

> to see the tree created by the subsystem. This can race with configfs'

> management of the hierarchy, so configfs uses the subsystem mutex to

> protect modifications. Whenever a subsystem wants to navigate the

> hierarchy, it must do so under the protection of the subsystem

> mutex.

Without proper locking, if a userdata item is added or removed

concurrently while these functions are iterating, the list can be

accessed

/// 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