Linux Kernel up to 6.7.6 md sync_thread denial of service

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.7.6. This affects the function sync_thread of the component md. Such manipulation leads to denial of service. This vulnerability is referenced as CVE-2024-26756. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.7.6 and classified as critical. Affected by this issue is the function sync_thread of the component md. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: md: Don't register sync_thread for reshape directly Currently, if reshape is interrupted, then reassemble the array will register sync_thread directly from pers->run(), in this case 'MD_RECOVERY_RUNNING' is set directly, however, there is no guarantee that md_do_sync() will be executed, hence stop_sync_thread() will hang because 'MD_RECOVERY_RUNNING' can't be cleared. Last patch make sure that md_do_sync() will set MD_RECOVERY_DONE, however, following hang can still be triggered by dm-raid test shell/lvconvert-raid-reshape.sh occasionally: [root@fedora ~]# cat /proc/1982/stack [] stop_sync_thread+0x1ab/0x270 [md_mod] [] md_frozen_sync_thread+0x5c/0xa0 [md_mod] [] raid_presuspend+0x1e/0x70 [dm_raid] [] dm_table_presuspend_targets+0x40/0xb0 [dm_mod] [] __dm_destroy+0x2a5/0x310 [dm_mod] [] dm_destroy+0x16/0x30 [dm_mod] [] dev_remove+0x165/0x290 [dm_mod] [] ctl_ioctl+0x4bb/0x7b0 [dm_mod] [] dm_ctl_ioctl+0x11/0x20 [dm_mod] [] vfs_ioctl+0x21/0x60 [] __x64_sys_ioctl+0xb9/0xe0 [] do_syscall_64+0xc6/0x230 [] entry_SYSCALL_64_after_hwframe+0x6c/0x74 Meanwhile mddev->recovery is: MD_RECOVERY_RUNNING | MD_RECOVERY_INTR | MD_RECOVERY_RESHAPE | MD_RECOVERY_FROZEN Fix this problem by remove the code to register sync_thread directly from raid10 and raid5. And let md_check_recovery() to register sync_thread.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2024-26756 since 02/19/2024. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 276115 (TencentOS Server 4: kernel (TSSA-2025:0438)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.7.7 or 6.8 eliminates this vulnerability. Applying the patch 13b520fb62b7/ad39c08186f8 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 (276115) and CERT Bund (WID-SEC-2024-0773). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• NetApp FAS
• EMC Avamar
• Oracle VM
• NetApp AFF
• Dell NetWorker
• IBM Security Guardium
• RESF Rocky Linux
• Open Source Linux Kernel
• SolarWinds Security Event Manager
• Broadcom Brocade SANnav
• IBM Business Automation Workflow
• IBM Spectrum Protect Plus
• IBM QRadar SIEM
• Juniper Junos Space
• IBM DB2
• IBM Storage Scale System

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.7.0
• 6.7.1
• 6.7.2
• 6.7.3
• 6.7.4
• 6.7.5
• 6.7.6

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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