Junglewise Threat Intelligence

CVE-2026-46080: Linux kernel OCFS2 credit exhaustion in direct I/O completion

CVE-2026-46080 · Severity: info · CVSS 0 · Published 2026-05-27

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability was identified in the Linux kernel's OCFS2 file system component that could lead to system instability or data corruption. The issue occurs when the system handles large direct I/O write operations, potentially exhausting the 'credits' used to track file system changes. If a system crash occurs during these operations, it could leave the file system in an inconsistent state with stale data blocks.

Technical details

A vulnerability in the OCFS2 file system's direct I/O (DIO) completion path (`ocfs2_dio_end_io_write`) can cause JBD2 credit exhaustion. When processing a large number of extents, the transaction may request more credits than the journal's maximum limit, triggering a kernel warning or failure in `jbd2__journal_restart`. Additionally, the improper ordering of orphan inode removal (`ocfs2_del_inode_from_orphan`) relative to extent tree updates created a window where a system crash could leave stale blocks beyond the end-of-file (EOF). The fix implements transaction batching for extent handling and reorders orphan list management to ensure atomicity and consistency.

Affected products

  • Linux Linux kernel All versions supporting OCFS2

Timeline

  • 2026-04-02: patched: Initial patch submitted by Heming Zhao
  • 2026-05-27: advisory: CVE-2026-46080 published by kernel.org and NVD

References

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