CVE-2025-38302
📋 TL;DR
A race condition vulnerability in the Linux kernel's block layer can cause system deadlocks when freezing storage queues with pending zone write plugs. This affects Linux systems using zoned block devices (like SMR HDDs or ZNS SSDs) and can lead to denial of service. The vulnerability is in the kernel's internal bio submission logic.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Complete system deadlock requiring hard reboot, causing extended downtime and potential data corruption on affected storage devices.
Likely Case
Temporary I/O freezes or system hangs when storage operations conflict with queue freezing operations, leading to service disruption.
If Mitigated
Minor performance impact during specific storage operations with no security compromise.
🎯 Exploit Status
Exploitation requires local access and ability to trigger specific storage operations on zoned devices. Race conditions are timing-sensitive.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel branches via the provided git commits
Vendor Advisory: https://git.kernel.org/stable/c/0fccb6773b1f4f992e435582cf8e050de421b678
Restart Required: Yes
Instructions:
1. Update to patched kernel version from your distribution. 2. For custom kernels: apply commits 0fccb6773b1f4f992e435582cf8e050de421b678, 6ffae5d53f704d300cc73b06b4ea99e4507f7cf1, or cf625013d8741c01407bbb4a60c111b61b9fa69d. 3. Reboot system.
🔧 Temporary Workarounds
Disable zoned block device usage
linuxAvoid using SMR HDDs, ZNS SSDs, or other zoned storage devices on vulnerable systems
Limit storage operations during maintenance
linuxAvoid freezing storage queues while zoned device operations are active
🧯 If You Can't Patch
- Monitor system for I/O hangs and have reboot procedures ready
- Isolate systems with zoned storage devices from untrusted users
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if zoned block devices are in use: 'uname -r' and 'lsblk -o NAME,ZONED'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is patched and test zoned device operations during queue freeze scenarios📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing I/O timeouts
- Storage subsystem errors
- System hang messages in dmesg
Network Indicators:
- None - local vulnerability
SIEM Query:
Search for: 'kernel: I/O error', 'block: timeout', 'system hang' in system logs