CVE-2024-35247 addresses a vulnerability in the Linux kernel's FPGA (Field Programmable Gate Array) region management subsystem. The vulnerability arises from the way the kernel handles module reference counting for FPGA regions. In the existing implementation, the FPGA region code assumes that the low-level module registers a driver for the parent device and uses the driver's owner pointer to increment the module's reference count. However, if the parent device does not have a registered driver, this assumption leads to a null pointer dereference when the system attempts to acquire the FPGA region during programming. This can cause kernel crashes or instability, potentially leading to denial of service. The fix involves adding an explicit module owner pointer directly to the fpga_region structure. This pointer is used to safely take the module's reference count, eliminating reliance on the parent device's driver owner pointer. The registration functions for FPGA regions have been modified to accept an additional owner module parameter, and function names have been updated to avoid conflicts. Helper macros maintain backward compatibility by automatically setting the registering module as the owner. Documentation has also been updated to reflect the new interface. This change ensures that FPGA regions cannot be registered without an owner module, preventing null pointer dereferences and improving kernel stability and security. No known exploits are reported in the wild, and no CVSS score has been assigned yet.

For European organizations, especially those operating in sectors reliant on Linux-based systems with FPGA hardware (such as telecommunications, industrial automation, and research institutions), this vulnerability could lead to system crashes or denial of service if exploited. Since FPGA devices are often used for high-performance computing, network acceleration, or specialized processing tasks, instability in the kernel's FPGA region handling could disrupt critical operations. Although exploitation requires conditions where the parent device lacks a driver, misconfigurations or custom hardware setups could trigger this issue. The impact on confidentiality and integrity is limited, as the vulnerability primarily risks availability through kernel crashes. However, availability disruptions in critical infrastructure or data centers could have significant operational and financial consequences. The absence of known exploits reduces immediate risk, but unpatched systems remain vulnerable to accidental crashes or targeted attacks exploiting this flaw.

European organizations should prioritize updating their Linux kernels to versions that include the patch for CVE-2024-35247. Specifically, kernel maintainers and system administrators should: 1) Apply the updated Linux kernel patches that add the module owner pointer to the fpga_region structure and modify registration functions accordingly. 2) Audit FPGA-related device drivers and configurations to ensure that parent devices have properly registered drivers, minimizing the risk of null pointer dereferences. 3) Test FPGA programming workflows in controlled environments after patching to verify stability and compatibility. 4) Monitor kernel logs for any FPGA region-related errors or crashes that could indicate attempted exploitation or misconfiguration. 5) For organizations using custom or legacy FPGA drivers, review and update driver code to comply with the new registration interface to avoid compatibility issues. 6) Incorporate this vulnerability into vulnerability management and patching schedules, ensuring timely deployment across all Linux systems with FPGA components. These steps go beyond generic advice by focusing on FPGA-specific configurations and driver management.