CVE-2022-49189
📋 TL;DR
A Linux kernel vulnerability in the Qualcomm clock controller driver (clk-rcg2) allows underflow errors when calculating display pixel clock values. This affects systems with newer Qualcomm platforms using specific M/N ratios, potentially causing display issues or system instability. Only Linux systems with Qualcomm hardware and affected kernel versions are impacted.
💻 Affected Systems
- Linux kernel with Qualcomm clock controller 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 →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
Kernel panic or system crash leading to denial of service, potentially requiring physical access to restart affected devices.
Likely Case
Display corruption, flickering, or failure to initialize display hardware on affected Qualcomm-based devices.
If Mitigated
Minor display artifacts or no visible impact if the vulnerable code path isn't triggered by specific clock configurations.
🎯 Exploit Status
Exploitation requires specific hardware conditions and kernel access; more likely to be triggered accidentally than maliciously.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 334720f418f57b1d969dad2117b21f9388cb9395, 34dca60982e93e69ae442aa2d36ce61c9a3bb563, 52592f9afbfe01bce8f8953e4f19cbe3bcbdbd3a, 58922910add18583d5273c2edcdb9fd7bf4eca02, 96888f0dcf351e758b9df57e015a48427ca709c1
Vendor Advisory: https://git.kernel.org/stable/c/334720f418f57b1d969dad2117b21f9388cb9395
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
Avoid specific display configurations
linuxPrevent using display modes that trigger the M/N = 2/3 ratio requirement
🧯 If You Can't Patch
- Monitor system logs for display driver errors or kernel panics
- Avoid hardware/display configurations known to trigger the issue on affected Qualcomm platforms
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if Qualcomm clk-rcg2 driver is loaded: lsmod | grep clk_rcg2 && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits or is newer than vulnerable versions📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Display driver errors in dmesg
- Clock controller underflow warnings
SIEM Query:
source="kernel" AND ("clk-rcg2" OR "underflow" OR "display panic")🔗 References
- https://git.kernel.org/stable/c/334720f418f57b1d969dad2117b21f9388cb9395
- https://git.kernel.org/stable/c/34dca60982e93e69ae442aa2d36ce61c9a3bb563
- https://git.kernel.org/stable/c/52592f9afbfe01bce8f8953e4f19cbe3bcbdbd3a
- https://git.kernel.org/stable/c/58922910add18583d5273c2edcdb9fd7bf4eca02
- https://git.kernel.org/stable/c/96888f0dcf351e758b9df57e015a48427ca709c1
- https://git.kernel.org/stable/c/a4e2e31971354790b0d1fa3e783452a9d135fcff
