CVE-2022-48826
📋 TL;DR
This CVE describes a deadlock vulnerability in the Linux kernel's VC4 DSI driver that occurs when a DSI device attach fails during probe retry. The deadlock prevents proper DSI display operation and can cause system instability. Systems using affected Linux kernel versions with VC4 DSI hardware are vulnerable.
💻 Affected Systems
- Linux kernel with VC4 DSI 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 →⚠️ Risk & Real-World Impact
Worst Case
System deadlock requiring hard reboot, potential data loss or corruption, and denial of service for DSI display functionality.
Likely Case
DSI display failure during device initialization, requiring system restart to recover display functionality.
If Mitigated
Minor disruption during device probe with automatic recovery after system restart.
🎯 Exploit Status
Exploitation requires triggering specific error conditions during DSI device attach, typically during hardware initialization or probe retry scenarios.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 0a3d12ab5097b1d045e693412e6b366b7e82031b, 770d1ba9a8201ce9bee0946eb03746449b6f3b80, dddd832f35096fbc5004e3a7e58fb4d2cefb8deb
Vendor Advisory: https://git.kernel.org/stable/c/0a3d12ab5097b1d045e693412e6b366b7e82031b
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For distributions: Use package manager (apt/yum/dnf) to update kernel package. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable DSI hardware if not needed
linuxPrevent DSI device initialization by disabling the VC4 DSI driver or hardware in kernel configuration
echo 'blacklist vc4' >> /etc/modprobe.d/blacklist.conf
update-initramfs -u
🧯 If You Can't Patch
- Avoid hardware changes or reboots that could trigger DSI device re-probing
- Monitor system logs for DSI attach errors and restart affected services if deadlock occurs
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if VC4 DSI driver is loaded: lsmod | grep vc4 && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits and test DSI display functionality📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing 'rt_mutex_slowlock' deadlock
- DSI attach error messages
- VC4 driver probe failures
SIEM Query:
source="kernel" AND ("rt_mutex_slowlock" OR "vc4_dsi" OR "DSI attach" OR deadlock)🔗 References
- https://git.kernel.org/stable/c/0a3d12ab5097b1d045e693412e6b366b7e82031b
- https://git.kernel.org/stable/c/770d1ba9a8201ce9bee0946eb03746449b6f3b80
- https://git.kernel.org/stable/c/dddd832f35096fbc5004e3a7e58fb4d2cefb8deb
- https://git.kernel.org/stable/c/0a3d12ab5097b1d045e693412e6b366b7e82031b
- https://git.kernel.org/stable/c/770d1ba9a8201ce9bee0946eb03746449b6f3b80
- https://git.kernel.org/stable/c/dddd832f35096fbc5004e3a7e58fb4d2cefb8deb
