Unity Linux 20.1060e / 20.1070e Security Update: kernel (UTSA-2025-992555)

high Nessus Plugin ID 280483

Synopsis

The Unity Linux host is missing one or more security updates.

Description

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2025-992555 advisory.

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

sched, cpuset: Fix dl_cpu_busy() panic due to empty cs->cpus_allowed

With cgroup v2, the cpuset's cpus_allowed mask can be empty indicating that the cpuset will just use the effective CPUs of its parent. So cpuset_can_attach() can call task_can_attach() with an empty mask.
This can lead to cpumask_any_and() returns nr_cpu_ids causing the call to dl_bw_of() to crash due to percpu value access of an out of bound CPU value. For example:

[80468.182258] BUG: unable to handle page fault for address: ffffffff8b6648b0 :
[80468.191019] RIP: 0010:dl_cpu_busy+0x30/0x2b0 :
[80468.207946] Call Trace:
[80468.208947] cpuset_can_attach+0xa0/0x140 [80468.209953] cgroup_migrate_execute+0x8c/0x490 [80468.210931] cgroup_update_dfl_csses+0x254/0x270 [80468.211898] cgroup_subtree_control_write+0x322/0x400 [80468.212854] kernfs_fop_write_iter+0x11c/0x1b0 [80468.213777] new_sync_write+0x11f/0x1b0 [80468.214689] vfs_write+0x1eb/0x280 [80468.215592] ksys_write+0x5f/0xe0 [80468.216463] do_syscall_64+0x5c/0x80 [80468.224287] entry_SYSCALL_64_after_hwframe+0x44/0xae

Fix that by using effective_cpus instead. For cgroup v1, effective_cpus is the same as cpus_allowed. For v2, effective_cpus is the real cpumask to be used by tasks within the cpuset anyway.

Also update task_can_attach()'s 2nd argument name to cs_effective_cpus to reflect the change. In addition, a check is added to task_can_attach() to guard against the possibility that cpumask_any_and() may return a value >= nr_cpu_ids.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected kernel package.

Plugin Details

Severity: High

ID: 280483

File Name: unity_linux_UTSA-2025-992555.nasl

Version: 1.1

Type: local

Family: Unity Linux Local Security Checks

Published: 12/30/2025

Updated: 12/30/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.0

CVSS v2

Risk Factor: Medium

Base Score: 6.2

Temporal Score: 4.6

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:N/A:C

CVSS Score Source: CVE-2022-50103

CVSS v3

Risk Factor: High

Base Score: 7.1

Temporal Score: 6.2

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/UOS-Server/release, Host/UOS-Server/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 12/30/2025

Vulnerability Publication Date: 10/11/2022

Reference Information

CVE: CVE-2022-50103

Detections

Analytics