Use After Free Affecting kernel-tools package, versions <0:4.18.0-553.5.1.el8_10


Severity

Recommended
medium

Based on CentOS security rating.

Threat Intelligence

EPSS
0.04% (6th percentile)

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  • Snyk IDSNYK-CENTOS8-KERNELTOOLS-6260445
  • published21 Feb 2024
  • disclosed20 Feb 2024

Introduced: 20 Feb 2024

CVE-2023-52439  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Centos:8 kernel-tools to version 0:4.18.0-553.5.1.el8_10 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-tools package and not the kernel-tools package as distributed by Centos. See How to fix? for Centos:8 relevant fixed versions and status.

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

uio: Fix use-after-free in uio_open

core-1 core-2

uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev)

In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. Then:

  1. After core-1 kfree idev, the core-2 will do use-after-free for idev.
  2. When core-2 do uio_release and put_device, the idev will be double freed.

To address this issue, we can get idev atomic & inc idev reference with minor_lock.

CVSS Scores

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