CVE-2025-37978 is a vulnerability identified in the Linux kernel's block integrity subsystem. The issue arises from the improper invocation of the function set_page_dirty_lock() within interrupt context when handling multiple protection information buffers placed inside the same memory page. Specifically, the Linux kernel code called set_page_dirty_lock() on pages that contain protection information buffers, which are not backed by any file and thus do not require synchronization. Calling set_page_dirty_lock() in interrupt context is unsafe and can lead to kernel oops (crashes) due to the function's inability to operate correctly outside of process context. The vulnerability is rooted in the block integrity code path, where the last argument to bio_integrity_unpin_bvec() was removed and the call to set_page_dirty_lock() was dropped to prevent these unsafe calls. This fix prevents kernel crashes caused by the mishandling of protection information buffers in the block layer. While no known exploits are currently reported in the wild, the vulnerability could potentially be triggered by crafted I/O operations that manipulate block device integrity buffers, causing denial of service via kernel panic or oops. The affected versions correspond to a specific Linux kernel commit hash, indicating this is a recent and targeted fix within the kernel source tree. No CVSS score has been assigned yet, and no additional CWE identifiers are provided. The vulnerability is technical and low-level, impacting kernel stability rather than directly exposing confidentiality or integrity breaches.

For European organizations relying on Linux-based systems, especially those using block devices with integrity protection features (such as enterprise storage servers, cloud infrastructure, or embedded systems), this vulnerability poses a risk of system instability and denial of service. Kernel oops or crashes can disrupt critical services, leading to downtime and potential data unavailability. Although this vulnerability does not appear to allow privilege escalation or data leakage, the resulting system crashes could impact availability of services, which is critical in sectors such as finance, healthcare, and public infrastructure. Organizations running Linux kernels with the affected code may experience unexpected reboots or kernel panics under specific I/O workloads, potentially affecting high-availability systems. Given the widespread use of Linux in European data centers and cloud environments, the impact could be significant if exploited or triggered unintentionally. However, the lack of known exploits and the technical nature of the flaw suggest the immediate risk is moderate, primarily affecting system reliability rather than security confidentiality or integrity.

European organizations should prioritize updating their Linux kernel to the patched version that removes the unsafe call to set_page_dirty_lock() in interrupt context. Kernel upgrades should be tested in staging environments to ensure compatibility with existing workloads, especially those involving block device integrity features. System administrators should monitor kernel logs for oops or panic messages related to block integrity operations, which may indicate attempts to trigger this vulnerability. For environments where immediate kernel upgrades are not feasible, consider limiting or isolating workloads that perform intensive block device integrity operations or use protection information buffers. Additionally, organizations should implement robust system monitoring and automated reboot procedures to minimize downtime in case of kernel crashes. Engaging with Linux distribution vendors for timely security patches and advisories is critical. Finally, maintaining comprehensive backups and disaster recovery plans will mitigate the impact of potential denial of service caused by this vulnerability.