{"id":"CVE-2025-68319","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetconsole: Acquire su_mutex before navigating configs hierarchy\n\nThere is a race between operations that iterate over the userdata\ncg_children list and concurrent add/…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetconsole: Acquire su_mutex before navigating configs hierarchy\n\nThere is a race between operations that iterate over the userdata\ncg_children list and concurrent add/…","severity":"none","published":"2025-12-16","updated":"2026-10-13","sourceUpdated":"2026-10-13T11:10:00.203","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-68319","references":[{"url":"https://git.kernel.org/stable/c/d7d2fcf7ae31471b4e08b7e448b8fd0ec2e06a1b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ff70aa7e8cf05745fdba7258952a8bedf33ea336","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00176,"epssPercentile":0.06505,"ingestedAt":"2026-10-13T11:23:51.106Z","slug":"CVE-2025-68319","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetconsole: Acquire su_mutex before navigating configs hierarchy\n\nThere is a race between operations that iterate over the userdata\ncg_children list and concurrent add/remove of userdata items through\nconfigfs. The update_userdata() function iterates over the\nnt->userdata_group.cg_children list, and count_extradata_entries() also\niterates over this same list to count nodes.\n\nQuoting from Documentation/filesystems/configfs.rst:\n> A subsystem can navigate the cg_children list and the ci_parent pointer\n> to see the tree created by the subsystem.  This can race with configfs'\n> management of the hierarchy, so configfs uses the subsystem mutex to\n> protect modifications.  Whenever a subsystem wants to navigate the\n> hierarchy, it must do so under the protection of the subsystem\n> mutex.\n\nWithout proper locking, if a userdata item is added or removed\nconcurrently while these functions are iterating, the list can be\naccessed in an inconsistent state. For example, the list_for_each() loop\ncan reach a node that is being removed from the list by list_del_init()\nwhich sets the nodes' .next pointer to point to itself, so the loop will\nnever end (or reach the WARN_ON_ONCE in update_userdata() ).\n\nFix this by holding the configfs subsystem mutex (su_mutex) during all\noperations that iterate over cg_children.\nThis includes:\n- userdatum_value_store() which calls update_userdata() to iterate over\n  cg_children\n- All sysdata_*_enabled_store() functions which call\n  count_extradata_entries() to iterate over cg_children\n\nThe su_mutex must be acquired before dynamic_netconsole_mutex to avoid\npotential lock ordering issues, as configfs operations may already hold\nsu_mutex when calling into our code.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}