Welcome to our comprehensive guide on CVE-2024-45029, a critical bug identified in the Linux kernel. As your trusted source at LinuxPatch, we aim to provide a clear and detailed explanation of this issue to ensure your systems remain secure and up-to-date. This analysis will help Linux users and administrators understand the technicalities, implications, and the corrective measures for this specific vulnerability.
CVE-2024-45029 is a recently discovered vulnerability within the Linux kernel, specifically affecting the i2c tegra module on ACPI (Advanced Configuration and Power Interface) machines. This medium-severity issue has been assigned a CVSS (Common Vulnerability Scoring System) score of 5.5, reflecting a significant impact on affected systems.
During operations in ACPI configuration, the i2c tegra module of the Linux Kernel is tasked with managing communication protocols that integrate various hardware components. A critical section of this process involves power management and device state transitions, which are handled by calling the __pm_runtime_resume() function.
Here’s where the problem lies: the &dev->power.lock spinlock is acquired as part of the device’s power management sequence. Subsequently, rpm_resume() is executed, which in turn calls acpi_subsys_runtime_resume(). This function relies on mutexes, a type of blocking lock, to ensure thread safety during multi-threaded operations.
However, invoking a mutex lock within a spinlock context, as seen in this scenario, is fundamentally flawed. It results in a system bug often manifested as BUG: sleeping function called from invalid context, which can halt or severely disrupt system operations.
This flaw primarily affects systems that use the i2c tegra module on ACPI-enabled devices. Systems could experience halts and significant disruptions, particularly in scenarios involving device power management. The erroneous handling of locks can potentially lead to unpredictable behavior, ranging from minor lags to complete system crashes under certain conditions.
In response to CVE-2024-45029, the developers addressed the issue by modifying the handling of ACPI devices in the i2c tegra module. Now, these devices are specifically marked as not IRQ-safe, acknowledging the limitations enforced by the dependency on mutexes in acpi_subsys_runtime_resume(). This alteration effectively avoids the bug by preventing the kernel from making unsafe calls that could lead to a lockup.
For users and system administrators, it is crucial to apply the updated patches provided by the Linux community or your Linux distribution's maintainer as soon as they are available. Keeping your system’s kernel updated is a key step in protecting against vulnerabilities like CVE-2024-45029.
Understanding and addressing CVE-2024-45029 is vital for maintaining system stability and security, especially for those utilizing the affected i2c tegra module in ACPI configurations. By staying informed about such vulnerabilities and applying necessary updates, Linux users can ensure their systems remain robust against potential security threats. Stay secure by keeping an eye on updates from LinuxPatch and ensure your systems are always running the latest, most secure software versions.