CVE-2022-48931: Linux Kernel

Medium severity, CVSS 4.7. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: configfs: fix a race in configfs_{,un}register_subsystem() When configfs_register_subsystem() or configfs_unregister_subsystem() is executing link_group() or unlink_group(), it is possible that two processes add or delete list concurrently. Some unfortunate interleavings of them can cause kernel panic. One of cases is: A --> B --> C --> D A <-- B <-- C <-- D delete list_head *B | delete list_head *C --------------------------------|----------------------------------- configfs_unregister_subsystem | configfs_unregister_subsystem unlink_group | unlink_group unlink_obj | unlink_obj list_del_init | list_del_init __list_del_entry | __list_del_entry __list_del | __list_del // next == C | next->prev = prev | | next->prev = prev prev->next = next | | // prev == B | prev->next = next Fix this by adding mutex when calling link_group() or unlink_group(), but parent configfs_subsystem is NULL when config_item is root. So I create a mutex configfs_subsystem_mutex.

Affected products

• Linux Linux Kernel: from 2.6.16, before 4.9.304 (fixed in 4.9.304); from 4.10, before 4.14.269 (fixed in 4.14.269); from 4.15, before 4.19.232 (fixed in 4.19.232); from 4.20, before 5.4.182 (fixed in 5.4.182); from 5.5, before 5.10.103 (fixed in 5.10.103); from 5.11, before 5.15.26 (fixed in 5.15.26); …

Published 2024-08-22. Last modified 2026-06-17.