CVE-2022-49469 is a vulnerability identified in the Linux kernel's Btrfs filesystem implementation, specifically within the create_subvol() function. The issue arises due to improper error handling when certain internal functions—btrfs_qgroup_inherit(), btrfs_alloc_tree_block(), or btrfs_insert_root()—fail during the creation of a subvolume. In these failure scenarios, the kernel fails to free an anonymous device (anon_dev) resource, leading to a resource leak. This leak can cause the accumulation of unreleased anon_dev objects, potentially degrading system performance or causing resource exhaustion over time. The vulnerability does not appear to directly allow privilege escalation, code execution, or data corruption but represents a robustness flaw in resource management within the Btrfs subsystem. The flaw was addressed by reorganizing the error handling logic in create_subvol() to ensure anon_dev is properly freed upon failure of the aforementioned functions. The vulnerability affects Linux kernel versions identified by the commit hash 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and was published on February 26, 2025. There are no known exploits in the wild, and no CVSS score has been assigned to this vulnerability.

For European organizations, the impact of CVE-2022-49469 is primarily related to system stability and resource management on Linux systems using the Btrfs filesystem. Organizations that deploy Btrfs for data storage, particularly in environments with frequent subvolume creation and deletion (such as cloud infrastructure, virtualization hosts, or container storage backends), may experience gradual resource leaks leading to degraded performance or potential denial of service due to resource exhaustion. While this does not directly compromise confidentiality or integrity, the availability of critical systems could be affected if the leak is left unmitigated, especially in large-scale deployments. Given the widespread use of Linux in European enterprise and public sector infrastructure, particularly in servers and cloud environments, the vulnerability could impact operational continuity if not addressed. However, the absence of known exploits and the requirement for specific filesystem usage limit the immediate risk.

European organizations should prioritize updating Linux kernel versions to include the patch that fixes the anon_dev leak in create_subvol(). Specifically, kernel versions incorporating the fix after the commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 should be deployed. System administrators should audit their environments to identify systems using Btrfs, especially those performing frequent subvolume operations. Monitoring resource usage related to anon_dev allocations can help detect potential leaks before they impact system availability. For environments where kernel upgrades are not immediately feasible, implementing operational controls such as limiting subvolume creation rates or scheduling regular system reboots may mitigate resource exhaustion risks. Additionally, organizations should maintain robust backup and recovery procedures to minimize disruption in case of system instability. Finally, staying informed through Linux kernel mailing lists and security advisories will help ensure timely application of future patches.