CVE-2024-47693 is a vulnerability identified in the Linux kernel specifically within the InfiniBand (IB) core subsystem. The issue arises in the error handling path of the function ib_cache_setup_one. When the function ib_cache_update returns an error, the current implementation exits ib_cache_setup_one immediately without performing proper cleanup. Prior to this error return, the function successfully executes gid_table_setup_one, which allocates or initializes resources related to the gid_table. However, due to the premature exit, the corresponding cleanup function gid_table_cleanup_one is not called, leading to resource leaks and kernel warnings. This improper cleanup can cause kernel instability, as evidenced by the kernel WARN message and the call trace involving gid_table_release_one. The vulnerability is rooted in a logic flaw in error flow management, which can lead to inconsistent kernel state and potential denial of service (DoS) conditions due to resource exhaustion or kernel panics. The issue affects multiple versions of the Linux kernel, including release candidates such as 6.11.0-rc1 and others identified by specific commit hashes. The vulnerability does not currently have a CVSS score and there are no known exploits in the wild. The fix involves ensuring that gid_table_cleanup_one is called appropriately before returning the error, thereby maintaining kernel stability and preventing resource leaks.

For European organizations, the impact of CVE-2024-47693 primarily concerns systems running Linux kernels with InfiniBand support enabled. InfiniBand is commonly used in high-performance computing (HPC) environments, data centers, and enterprise-grade servers for low-latency, high-throughput networking. Organizations relying on HPC clusters, scientific research facilities, financial institutions with latency-sensitive trading platforms, and cloud providers using InfiniBand for backend connectivity could experience kernel instability or denial of service if this vulnerability is triggered. While the vulnerability does not directly allow privilege escalation or remote code execution, the resulting kernel warnings and potential crashes could disrupt critical services, leading to downtime and operational impact. Given the widespread use of Linux in European data centers and research institutions, the vulnerability could affect availability and reliability of critical infrastructure. However, the absence of known exploits and the requirement for specific kernel configurations limit the immediate risk. Nonetheless, unpatched systems remain vulnerable to accidental or malicious triggering of the bug, which could be leveraged in targeted attacks to degrade service availability.

European organizations should prioritize applying the official Linux kernel patches that address this error handling flaw in the InfiniBand core subsystem. Specifically, ensure that the kernel version in use includes the fix that calls gid_table_cleanup_one properly during error returns in ib_cache_setup_one. For environments where immediate patching is not feasible, consider disabling InfiniBand support if it is not required, to mitigate exposure. Additionally, implement kernel crash monitoring and alerting to detect any WARN messages or instability related to gid_table_release_one. Regularly audit kernel logs for signs of this issue. For HPC and data center environments, coordinate with hardware vendors and Linux distribution maintainers to obtain timely updates. Employ robust system hardening and access controls to limit the ability of unprivileged users to trigger kernel operations that may expose the vulnerability. Finally, maintain comprehensive backup and recovery procedures to minimize downtime in case of kernel crashes.