CVE-2024-49932 is a vulnerability identified in the Linux kernel's Btrfs filesystem implementation, specifically related to the handling of relocation inodes during readahead operations on filesystems backed by RAID stripe trees (RST). The issue arises because the kernel attempts to perform readahead on the relocation inode during block group relocation. However, when the filesystem uses a RAID stripe profile, certain preallocated extents may not be mapped in the RST, causing the lookup to fail with an ENOENT (No such file or directory) error. The readahead mechanism does not properly handle this error condition and proceeds to submit invalid read requests to the underlying device. This leads to an assertion failure in the scatter-gather list code, resulting in a kernel BUG and system crash (kernel panic). The vulnerability manifests as a denial-of-service (DoS) condition due to the kernel panic triggered by invalid memory operations during block relocation. The detailed kernel oops trace shows the failure occurring in the __blk_rq_map_sg function, which is responsible for mapping block requests to scatter-gather lists. This bug affects Linux kernel versions including the 6.10.0-rc7+ release candidate and likely others with similar Btrfs and RAID0 support. The vulnerability is triggered during Btrfs balance operations that relocate block groups with RAID0 profiles, which are used to distribute data across multiple devices for performance. No known exploits are reported in the wild as of the publication date. The issue is technical and specific to certain Btrfs configurations involving RAID stripe trees, making exploitation more complex and environment-dependent. However, the impact is significant as it can cause kernel crashes and service interruptions on affected systems.

For European organizations, the impact of CVE-2024-49932 can be substantial, particularly for those relying on Linux servers using Btrfs filesystems configured with RAID stripe profiles (e.g., RAID0). Such configurations are common in high-performance storage environments, including data centers, cloud service providers, and enterprises managing large-scale storage arrays. A successful trigger of this vulnerability results in a kernel panic, causing immediate denial of service and potential data unavailability. This can disrupt critical business operations, especially in sectors like finance, healthcare, telecommunications, and government services where uptime and data integrity are paramount. Additionally, repeated crashes may lead to data corruption or loss if not properly managed. The vulnerability does not appear to allow privilege escalation or remote code execution directly but can be exploited locally or via automated maintenance tasks (like Btrfs balance) that may be scheduled or triggered by system administrators or automated systems. The lack of user interaction requirement means that once the vulnerable configuration is present, the risk of accidental or malicious triggering exists. European organizations with strict regulatory requirements for data availability and integrity (e.g., GDPR mandates) may face compliance risks if service disruptions occur. Furthermore, organizations using Linux-based infrastructure for critical services must consider the operational risks posed by this vulnerability.

To mitigate CVE-2024-49932, European organizations should take the following specific actions: 1) Apply the latest Linux kernel patches that address this vulnerability as soon as they become available from trusted sources or Linux distributions. Monitoring vendor advisories and kernel mailing lists is essential. 2) Review and audit Btrfs filesystem configurations to identify the use of RAID stripe profiles, particularly RAID0, and assess the necessity of such configurations. Where possible, avoid or limit the use of RAID0 with Btrfs until patched. 3) Implement robust monitoring of system logs and kernel oops messages to detect early signs of this issue, enabling proactive intervention before service disruption. 4) Schedule Btrfs balance operations during maintenance windows with proper backups in place to minimize impact if a crash occurs. 5) Maintain comprehensive backups and disaster recovery plans for systems using Btrfs with RAID profiles to ensure data availability in case of kernel panics or data corruption. 6) Consider alternative filesystems or RAID configurations if Btrfs RAID0 is not critical, to reduce exposure. 7) Limit access to systems capable of triggering this vulnerability to trusted administrators to reduce the risk of accidental or malicious exploitation. These mitigations go beyond generic advice by focusing on configuration auditing, operational procedures, and proactive monitoring tailored to the nature of this vulnerability.