CVE-2022-49536
📋 TL;DR
This CVE describes a deadlock vulnerability in the Linux kernel's lpfc SCSI driver that can cause system lockups during high I/O stress with multiple virtual ports. It affects Linux systems using the lpfc driver for Fibre Channel storage. The vulnerability allows denial of service through system hangs.
💻 Affected Systems
- Linux kernel with lpfc SCSI driver
📦 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 lockup requiring hard reboot, causing extended downtime and potential data corruption on affected storage systems.
Likely Case
System hangs or performance degradation during high I/O operations with multiple vports, leading to service disruption.
If Mitigated
Minimal impact if systems aren't under heavy I/O stress with 500+ vports or if the lpfc driver isn't used.
🎯 Exploit Status
Exploitation requires specific hardware configuration (lpfc driver), high I/O stress, and multiple vports. Not easily weaponized for remote attacks.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits: 03cbbd7c2f5ee288f648f4aeedc765a181188553, 0c4eed901285b9cae36a622f32bea3e92490da6c, 21c0d469349957b5dc811c41200a2a998996ca8d, 7625e81de2164a082810e1f27547d388406da610
Vendor Advisory: https://git.kernel.org/stable/c/03cbbd7c2f5ee288f648f4aeedc765a181188553
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Check distribution-specific security advisories. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Limit vport count
linuxReduce number of virtual ports below 500 to avoid triggering the deadlock condition
Configure storage systems to use fewer than 500 vports
Monitor I/O load
linuxImplement monitoring to detect and prevent high I/O stress conditions
Use monitoring tools like iostat, vmstat to track I/O load
🧯 If You Can't Patch
- Implement strict I/O load monitoring and alerting
- Consider alternative storage drivers or configurations if possible
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if lpfc driver is loaded: lsmod | grep lpfc && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version contains fix commits and test with stress I/O on systems with 500+ vports📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- LOCKUP call traces in dmesg
- System hang events
Network Indicators:
- Storage I/O timeouts
- SCSI command failures
SIEM Query:
source="kernel" AND ("LOCKUP" OR "deadlock" OR "lpfc_abort_handler")