Debian: CVE-2022-48931: linux -- security update

Debian: CVE-2022-48931: linux -- security update

Severity

4

CVSS

(AV:L/AC:M/Au:S/C:N/I:N/A:C)

Published

08/22/2024

Created

08/24/2024

Added

08/23/2024

Modified

01/28/2025

Description

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.

Solution(s)

• debian-upgrade-linux

References

• https://attackerkb.com/topics/cve-2022-48931
• CVE - 2022-48931