CVE-2024-50178 is a vulnerability identified in the Linux kernel specifically related to the cpufreq driver for the Loongson3 processor architecture. The issue arises from the use of the function smp_processor_id() within the do_service_request() routine, which is executed in preemptible code context. Using smp_processor_id() in such a context is unsafe because it can lead to incorrect CPU identification due to preemption, potentially causing race conditions or logic errors. The correct function to use in this context is raw_smp_processor_id(), which returns the CPU ID without considering preemption and thus avoids these errors. The vulnerability manifests as kernel bugs or crashes, as indicated by the BUG message referencing smp_processor_id() usage in preemptible code, specifically triggered during the loongson3_cpufreq_probe operation. This flaw could lead to system instability or denial of service on affected systems running the vulnerable Linux kernel versions with the Loongson3 cpufreq driver enabled. The patch involves replacing smp_processor_id() with raw_smp_processor_id() in the affected code path to ensure safe CPU ID retrieval in preemptible contexts. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet.

For European organizations, the impact of CVE-2024-50178 is primarily related to system stability and availability on Linux systems using the Loongson3 CPU architecture with the cpufreq driver enabled. While Loongson processors are less common globally compared to x86 or ARM architectures, they are used in some specialized or research environments. Organizations relying on these systems could experience kernel crashes or unexpected reboots, leading to potential downtime and disruption of services. This could affect critical infrastructure or research facilities using Loongson-based Linux servers. However, the vulnerability does not appear to allow privilege escalation, data leakage, or remote code execution, limiting its impact to availability and integrity of affected systems. Since no exploits are known in the wild, the immediate risk is low, but unpatched systems remain vulnerable to potential future exploitation or accidental crashes. European entities with niche deployments of Loongson3 Linux servers should prioritize patching to maintain operational stability.

To mitigate CVE-2024-50178, organizations should: 1) Identify any Linux systems running on Loongson3 processors with the cpufreq driver enabled. 2) Apply the official Linux kernel patch that replaces smp_processor_id() with raw_smp_processor_id() in the do_service_request() function of the loongson3_cpufreq driver. 3) If immediate patching is not feasible, consider disabling the cpufreq driver for Loongson3 CPUs as a temporary workaround to prevent triggering the vulnerable code path. 4) Monitor system logs for kernel BUG messages related to smp_processor_id() usage in preemptible code to detect potential exploitation or instability. 5) Maintain up-to-date kernel versions and subscribe to Linux kernel security advisories for timely updates. 6) Conduct thorough testing of patches in staging environments before deployment to avoid unintended side effects.