Linux Kernel up to 6.9.9 deadline start_dl_timer reference count

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.9.9. This affects the function start_dl_timer of the component deadline. The manipulation results in reference count. This vulnerability is identified as CVE-2024-41023. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.9.9. Affected is the function start_dl_timer of the component deadline. The manipulation with an unknown input leads to a reference count vulnerability. CWE is classifying the issue as CWE-911. The product uses a reference count to manage a resource, but it does not update or incorrectly updates the reference count. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: sched/deadline: Fix task_struct reference leak During the execution of the following stress test with linux-rt: stress-ng --cyclic 30 --timeout 30 --minimize --quiet kmemleak frequently reported a memory leak concerning the task_struct: unreferenced object 0xffff8881305b8000 (size 16136): comm "stress-ng", pid 614, jiffies 4294883961 (age 286.412s) object hex dump (first 32 bytes): 02 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 .@.............. 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ debug hex dump (first 16 bytes): 53 09 00 00 00 00 00 00 00 00 00 00 00 00 00 00 S............... backtrace: [] dup_task_struct+0x30/0x540 [] copy_process+0x3d9/0x50e0 [] kernel_clone+0xb0/0x770 [] __do_sys_clone+0xb6/0xf0 [] do_syscall_64+0x5d/0xf0 [] entry_SYSCALL_64_after_hwframe+0x6e/0x76 The issue occurs in start_dl_timer(), which increments the task_struct reference count and sets a timer. The timer callback, dl_task_timer, is supposed to decrement the reference count upon expiration. However, if enqueue_task_dl() is called before the timer expires and cancels it, the reference count is not decremented, leading to the leak. This patch fixes the reference leak by ensuring the task_struct reference count is properly decremented when the timer is canceled.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2024-41023 since 07/12/2024. The exploitability is told to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 207773 (Oracle Linux 8 : kernel (ELSA-2024-7000)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.9.10 eliminates this vulnerability. Applying the patch 7a54d31face6/b58652db66c9 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 (207773) and CERT Bund (WID-SEC-2024-1722). Once again VulDB remains the best source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• NetApp FAS
• NetApp ActiveIQ Unified Manager
• Siemens SIMATIC S7
• Oracle VM
• IBM Security Guardium
• RESF Rocky Linux
• Broadcom Brocade SANnav
• Dell PowerScale
• Open Source Linux Kernel
• IBM QRadar SIEM
• Dell integrated Dell Remote Access Controller
• Dell Avamar
• IBM Storage Scale
• IBM Spectrum Protect Plus
• Juniper Junos Space
• IBM Storage Scale System
• SolarWinds Security Event Manager
• Dell PowerProtect Data Domain
• Dell PowerProtect Data Domain Management Center
• Dell PowerProtect Data Domain OS

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.9.0
• 6.9.1
• 6.9.2
• 6.9.3
• 6.9.4
• 6.9.5
• 6.9.6
• 6.9.7
• 6.9.8
• 6.9.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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