Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: kernel (UTSA-2025-383494)

medium Nessus Plugin ID 266972

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-2025-383494 advisory.

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

ocfs2: remove entry once instead of null-ptr-dereference in ocfs2_xa_remove()

Syzkaller is able to provoke null-ptr-dereference in ocfs2_xa_remove():

[ 57.319872] (a.out,1161,7):ocfs2_xa_remove:2028 ERROR: status = -12 [ 57.320420] (a.out,1161,7):ocfs2_xa_cleanup_value_truncate:1999 ERROR: Partial truncate while removing xattr overlay.upper. Leaking 1 clusters and removing the entry [ 57.321727] BUG: kernel NULL pointer dereference, address: 0000000000000004 [...] [ 57.325727] RIP: 0010:ocfs2_xa_block_wipe_namevalue+0x2a/0xc0 [...] [ 57.331328] Call Trace:
[ 57.331477] <TASK> [...] [ 57.333511] ? do_user_addr_fault+0x3e5/0x740 [ 57.333778] ? exc_page_fault+0x70/0x170 [ 57.334016] ? asm_exc_page_fault+0x2b/0x30 [ 57.334263] ? __pfx_ocfs2_xa_block_wipe_namevalue+0x10/0x10 [ 57.334596] ? ocfs2_xa_block_wipe_namevalue+0x2a/0xc0 [ 57.334913] ocfs2_xa_remove_entry+0x23/0xc0 [ 57.335164] ocfs2_xa_set+0x704/0xcf0 [ 57.335381] ? _raw_spin_unlock+0x1a/0x40 [ 57.335620] ? ocfs2_inode_cache_unlock+0x16/0x20 [ 57.335915] ? trace_preempt_on+0x1e/0x70 [ 57.336153] ? start_this_handle+0x16c/0x500 [ 57.336410] ? preempt_count_sub+0x50/0x80 [ 57.336656] ? _raw_read_unlock+0x20/0x40 [ 57.336906] ? start_this_handle+0x16c/0x500 [ 57.337162] ocfs2_xattr_block_set+0xa6/0x1e0 [ 57.337424] __ocfs2_xattr_set_handle+0x1fd/0x5d0 [ 57.337706] ? ocfs2_start_trans+0x13d/0x290 [ 57.337971] ocfs2_xattr_set+0xb13/0xfb0 [ 57.338207] ? dput+0x46/0x1c0 [ 57.338393] ocfs2_xattr_trusted_set+0x28/0x30 [ 57.338665] ? ocfs2_xattr_trusted_set+0x28/0x30 [ 57.338948] __vfs_removexattr+0x92/0xc0 [ 57.339182] __vfs_removexattr_locked+0xd5/0x190 [ 57.339456] ? preempt_count_sub+0x50/0x80 [ 57.339705] vfs_removexattr+0x5f/0x100 [...]

Reproducer uses faultinject facility to fail ocfs2_xa_remove() -> ocfs2_xa_value_truncate() with -ENOMEM.

In this case the comment mentions that we can return 0 if ocfs2_xa_cleanup_value_truncate() is going to wipe the entry anyway. But the following 'rc' check is wrong and execution flow do 'ocfs2_xa_remove_entry(loc);' twice:
* 1st: in ocfs2_xa_cleanup_value_truncate();
* 2nd: returning back to ocfs2_xa_remove() instead of going to 'out'.

Fix this by skipping the 2nd removal of the same entry and making syzkaller repro happy.

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.

See Also

http://www.nessus.org/u?9c03da16

https://nvd.nist.gov/vuln/detail/CVE-2024-50265

Plugin Details

Severity: Medium

ID: 266972

File Name: unity_linux_UTSA-2025-383494.nasl

Version: 1.1

Type: local

Published: 10/7/2025

Updated: 10/7/2025

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-2024-50265

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: 7/8/2025

Vulnerability Publication Date: 11/19/2024

Reference Information

CVE: CVE-2024-50265