Deadlock Vulnerability in Linux Kernel's BPF Timer Management
Summary
DEBIAN-CVE-2024-42239: In the Linux kernel, the following vulnerability has been resolved: bpf: Fail bpf_timer_cancel when callback is being cancelled Given a schedule: timer1 cb timer2 cb bpf_timer_cancel(timer2); bpf_timer_cancel(timer1); Bo... Affects linux versions < 6.9.10-1. Fixed in 6.9.10-1. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Habilume
Habit tracker with a companion that grows with you
Complete habits, earn Lume Points, and watch your Lume grow as you stay consistent.
Background
The Linux kernel is a core component of many operating systems, providing essential services for hardware management and system operations. It supports various functionalities, including process management, memory management, and device control. The kernel's BPF (Berkeley Packet Filter) subsystem allows for efficient packet filtering and network monitoring. However, a recent vulnerability has been identified in the BPF timer management, which can lead to deadlock situations under specific conditions.
Vulnerability Detail
In the Linux kernel, a vulnerability exists in the BPF timer management system where two timers can end up in a deadlock situation. When one timer attempts to cancel another while the second timer is also trying to cancel the first, both operations wait indefinitely for each other to complete. This is due to the synchronous nature of the cancellation process, which can lead to a system lockup. The issue arises from the lack of proper handling of concurrent cancellation requests, which can result in a busy wait loop and potential system instability.
How To Fix
Minimum fixed version
6.9.10-1
This is the first release that contains the fix.
sudo apt-get install --only-upgrade linuxTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
Currently, there are no specific workarounds provided for this vulnerability. It is recommended to apply the patch as soon as it is available to avoid potential deadlock situations.
Conclusion
The deadlock vulnerability in the Linux kernel's BPF timer management poses a significant risk to system stability. Users are strongly advised to update their kernel to the patched version 6.9.10-1 to prevent potential deadlocks. Monitoring tools like Vulert can assist in identifying vulnerabilities in your software.
See every vulnerability recorded for linux →
FAQ
The vulnerability is a deadlock issue in the BPF timer management of the Linux kernel, where concurrent cancellation requests can lead to system lockups.
The vulnerability affects the Linux kernel versions prior to 6.9.10-1 in Debian 13 and Debian 14.
You can check if your application is affected by using Vulert, which monitors open-source vulnerabilities in real-time. Visit Vulert Scanner to use the Vulert playground without any signup.
While there are no specific workarounds, it is crucial to plan for an update as soon as possible to mitigate the risk of deadlock.
If exploited, this vulnerability can lead to system lockups, causing performance degradation and potentially requiring a system restart.
References
Related vulnerabilities
Recent vulnerabilities recorded for linux.
Habilume
Habit tracker with a companion that grows with you
Complete habits, earn Lume Points, and watch your Lume grow as you stay consistent.
