CVE-2025-40179

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

ext4: verify orphan file size is not too big

In principle orphan file can be arbitrarily large. However orphan replay

needs to traverse it all and we also pin all its buffers in memory. Thus

filesystems with absurdly large orphan files can lead to big amounts of

memory consumed. Limit orphan file size to a sane value and also use

kvmalloc() for allocating array of block descriptor structures to avoid

large order allocations for sane but large orphan files.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References