Linux Kernel up to 6.7.11/6.8.2 dm-raid deadlock

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.7.11/6.8.2 and classified as critical. This impacts an unknown function of the component dm-raid. Executing a manipulation can lead to deadlock. This vulnerability is handled as CVE-2024-35794. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.7.11/6.8.2 and classified as critical. This vulnerability affects an unknown code of the component dm-raid. The manipulation with an unknown input leads to a deadlock vulnerability. The CWE definition for the vulnerability is CWE-833. The product contains multiple threads or executable segments that are waiting for each other to release a necessary lock, resulting in deadlock. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: dm-raid: really frozen sync_thread during suspend 1) commit f52f5c71f3d4 ("md: fix stopping sync thread") remove MD_RECOVERY_FROZEN from __md_stop_writes() and doesn't realize that dm-raid relies on __md_stop_writes() to frozen sync_thread indirectly. Fix this problem by adding MD_RECOVERY_FROZEN in md_stop_writes(), and since stop_sync_thread() is only used for dm-raid in this case, also move stop_sync_thread() to md_stop_writes(). 2) The flag MD_RECOVERY_FROZEN doesn't mean that sync thread is frozen, it only prevent new sync_thread to start, and it can't stop the running sync thread; In order to frozen sync_thread, after seting the flag, stop_sync_thread() should be used. 3) The flag MD_RECOVERY_FROZEN doesn't mean that writes are stopped, use it as condition for md_stop_writes() in raid_postsuspend() doesn't look correct. Consider that reentrant stop_sync_thread() do nothing, always call md_stop_writes() in raid_postsuspend(). 4) raid_message can set/clear the flag MD_RECOVERY_FROZEN at anytime, and if MD_RECOVERY_FROZEN is cleared while the array is suspended, new sync_thread can start unexpected. Fix this by disallow raid_message() to change sync_thread status during suspend. Note that after commit f52f5c71f3d4 ("md: fix stopping sync thread"), the test shell/lvconvert-raid-reshape.sh start to hang in stop_sync_thread(), and with previous fixes, the test won't hang there anymore, however, the test will still fail and complain that ext4 is corrupted. And with this patch, the test won't hang due to stop_sync_thread() or fail due to ext4 is corrupted anymore. However, there is still a deadlock related to dm-raid456 that will be fixed in following patches.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2024-35794. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 210815 (RHEL 9 : kernel (RHSA-2024:9315)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.7.12 or 6.8.3 eliminates this vulnerability. Applying the patch af916cb66a80/eaa8fc9b0928/16c4770c75b1 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 (210815) and CERT Bund (WID-SEC-2024-1188). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

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

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
• 6.7.7
• 6.7.8
• 6.7.9
• 6.7.10
• 6.7.11
• 6.8.0
• 6.8.1
• 6.8.2

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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