Unity Linux 20.1070e Security Update: kernel (UTSA-2025-987708)

medium Nessus Plugin ID 271023

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-2025-987708 advisory.

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

Fix page corruption caused by racy check in __free_pages

When we upgraded our kernel, we started seeing some page corruption like the following consistently:

BUG: Bad page state in process ganesha.nfsd pfn:1304ca page:0000000022261c55 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x1304ca flags: 0x17ffffc0000000() raw: 0017ffffc0000000 ffff8a513ffd4c98 ffffeee24b35ec08 0000000000000000 raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000 page dumped because: nonzero mapcount CPU: 0 PID: 15567 Comm: ganesha.nfsd Kdump: loaded Tainted: P B O 5.10.158-1.nutanix.20221209.el7.x86_64 #1 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/05/2016 Call Trace:
dump_stack+0x74/0x96 bad_page.cold+0x63/0x94 check_new_page_bad+0x6d/0x80 rmqueue+0x46e/0x970 get_page_from_freelist+0xcb/0x3f0 ? _cond_resched+0x19/0x40
__alloc_pages_nodemask+0x164/0x300 alloc_pages_current+0x87/0xf0 skb_page_frag_refill+0x84/0x110 ...

Sometimes, it would also show up as corruption in the free list pointer and cause crashes.

After bisecting the issue, we found the issue started from commit e320d3012d25 (mm/page_alloc.c: fix freeing non-compound pages):

if (put_page_testzero(page)) free_the_page(page, order);
else if (!PageHead(page)) while (order-- > 0) free_the_page(page + (1 << order), order);

So the problem is the check PageHead is racy because at this point we already dropped our reference to the page. So even if we came in with compound page, the page can already be freed and PageHead can return false and we will end up freeing all the tail pages causing double free.

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.

See Also

http://www.nessus.org/u?0e1b4cda

http://www.nessus.org/u?53f8fe8d

https://nvd.nist.gov/vuln/detail/CVE-2023-52739

Plugin Details

Severity: Medium

ID: 271023

File Name: unity_linux_UTSA-2025-987708.nasl

Version: 1.1

Type: local

Published: 10/21/2025

Updated: 10/21/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

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

CVSS Score Source: CVE-2023-52739

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/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/cpu, Host/UOS-Server/release, Host/UOS-Server/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 10/15/2025

Vulnerability Publication Date: 7/21/2021

Reference Information

CVE: CVE-2023-52739