Linux Kernel up to 5.4.199/5.10.123/5.15.48/5.18.5 hv_init_clocksource initialization

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.4.199/5.10.123/5.15.48/5.18.5. It has been rated as problematic. Affected is the function hv_init_clocksource. This manipulation causes initialization. This vulnerability is handled as CVE-2022-49726. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.4.199/5.10.123/5.15.48/5.18.5. It has been declared as problematic. Affected by this vulnerability is the function hv_init_clocksource. The manipulation with an unknown input leads to a initialization vulnerability. The CWE definition for the vulnerability is CWE-665. The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: clocksource: hyper-v: unexport __init-annotated hv_init_clocksource() EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the only in-tree call-site, arch/x86/kernel/cpu/mshyperv.c is never compiled as modular. (CONFIG_HYPERVISOR_GUEST is boolean)

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2022-49726 since 02/26/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 241018 (EulerOS 2.0 SP13 : kernel (EulerOS-SA-2025-1704)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.200, 5.10.124, 5.15.49 or 5.18.6 eliminates this vulnerability. Applying the patch cff3a7ce6e81418b6e8bac941779bbf5d342d626/db965e2757d95f695e606856418cd84003dd036d/0414eab7c78f3518143d383e448d44fc573ac6d2/937fcbb55a1e48a6422e87e8f49422c92265f102/245b993d8f6c4e25f19191edfbd8080b645e12b1 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (241018). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.4.199
• 5.10.123
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.18.0
• 5.18.1
• 5.18.2
• 5.18.3
• 5.18.4
• 5.18.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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