Unity Linux 20.1070e Security Update: kernel (UTSA-2025-990773)

high Nessus Plugin ID 275058

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-2025-990773 advisory.

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

i2c: piix4: Fix adapter not be removed in piix4_remove()

In piix4_probe(), the piix4 adapter will be registered in:

piix4_probe() piix4_add_adapters_sb800() / piix4_add_adapter() i2c_add_adapter()

Based on the probed device type, piix4_add_adapters_sb800() or single piix4_add_adapter() will be called.
For the former case, piix4_adapter_count is set as the number of adapters, while for antoher case it is not set and kept default *zero*.

When piix4 is removed, piix4_remove() removes the adapters added in piix4_probe(), basing on the piix4_adapter_count value.
Because the count is zero for the single adapter case, the adapter won't be removed and makes the sources allocated for adapter leaked, such as the i2c client and device.

These sources can still be accessed by i2c or bus and cause problems.
An easily reproduced case is that if a new adapter is registered, i2c will get the leaked adapter and try to call smbus_algorithm, which was already freed:

Triggered by: rmmod i2c_piix4 && modprobe max31730

BUG: unable to handle page fault for address: ffffffffc053d860 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 3752 Comm: modprobe Tainted: G Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:i2c_default_probe (drivers/i2c/i2c-core-base.c:2259) i2c_core RSP: 0018:ffff888107477710 EFLAGS: 00000246 ...
<TASK> i2c_detect (drivers/i2c/i2c-core-base.c:2302) i2c_core
__process_new_driver (drivers/i2c/i2c-core-base.c:1336) i2c_core bus_for_each_dev (drivers/base/bus.c:301) i2c_for_each_dev (drivers/i2c/i2c-core-base.c:1823) i2c_core i2c_register_driver (drivers/i2c/i2c-core-base.c:1861) i2c_core do_one_initcall (init/main.c:1296) do_init_module (kernel/module/main.c:2455) ...
</TASK>
---[ end trace 0000000000000000 ]---

Fix this problem by correctly set piix4_adapter_count as 1 for the single adapter so it can be normally removed.

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: 275058

File Name: unity_linux_UTSA-2025-990773.nasl

Version: 1.1

Type: local

Family: Unity Linux Local Security Checks

Published: 11/12/2025

Updated: 11/12/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

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

CVSS Score Source: CVE-2022-49900

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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: 11/12/2025

Vulnerability Publication Date: 5/1/2025

Reference Information

CVE: CVE-2022-49900

Detections

Analytics