Linux Kernel up to 6.8.7/6.9-rc4 fork hugetlb_dup_vma_private initialization

Summaryinfo

A vulnerability described as problematic has been identified in Linux Kernel up to 6.8.7/6.9-rc4. This impacts the function hugetlb_dup_vma_private of the component fork. Such manipulation leads to initialization. This vulnerability is listed as CVE-2024-27022. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 6.8.7/6.9-rc4. Affected by this issue is the function hugetlb_dup_vma_private of the component fork. The manipulation with an unknown input leads to a initialization vulnerability. Using CWE to declare the problem leads to 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. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: fork: defer linking file vma until vma is fully initialized Thorvald reported a WARNING [1]. And the root cause is below race: CPU 1 CPU 2 fork hugetlbfs_fallocate dup_mmap hugetlbfs_punch_hole i_mmap_lock_write(mapping); vma_interval_tree_insert_after -- Child vma is visible through i_mmap tree. i_mmap_unlock_write(mapping); hugetlb_dup_vma_private -- Clear vma_lock outside i_mmap_rwsem! i_mmap_lock_write(mapping); hugetlb_vmdelete_list vma_interval_tree_foreach hugetlb_vma_trylock_write -- Vma_lock is cleared. tmp->vm_ops->open -- Alloc new vma_lock outside i_mmap_rwsem! hugetlb_vma_unlock_write -- Vma_lock is assigned!!! i_mmap_unlock_write(mapping); hugetlb_dup_vma_private() and hugetlb_vm_op_open() are called outside i_mmap_rwsem lock while vma lock can be used in the same time. Fix this by deferring linking file vma until vma is fully initialized. Those vmas should be initialized first before they can be used.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2024-27022 since 02/19/2024. The exploitation is known to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 207776 (Oracle Linux 9 : kernel (ELSA-2024-6997)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.8.8 or 6.9-rc5 eliminates this vulnerability. Applying the patch abdb88dd272b/35e351780fa9 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 databases at Tenable (207776) and CERT Bund (WID-SEC-2024-1008). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Oracle VM
• EMC Avamar
• IBM QRadar SIEM
• Dell NetWorker
• IBM Security Guardium
• RESF Rocky Linux
• Broadcom Brocade SANnav
• Open Source Linux Kernel
• IBM Business Automation Workflow
• IBM Spectrum Protect Plus
• Dell Avamar
• Juniper Junos Space
• IBM DataPower Gateway
• IBM Storage Scale System
• SolarWinds Security Event Manager
• Dell PowerProtect Data Domain
• Dell PowerScale OneFS

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.8.0
• 6.8.1
• 6.8.2
• 6.8.3
• 6.8.4
• 6.8.5
• 6.8.6
• 6.8.7
• 6.9-rc1
• 6.9-rc2
• 6.9-rc3
• 6.9-rc4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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