Cloudanix VulnDB

CVE-2026-80879

None

CVSS

—

EPSS

0.2%

Published

Sep 4, 2026

CISA due date

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Cloudanix analysis

Schedule a fix SSVC: Track

A bug in Linux could make systems using a particular clustered storage filesystem freeze during routine file operations.

Exploitation
Local Privilege
Attacker needs
Local User
Complexity
Moderate
Impact
Denial Of Service
Component
OS kernel
Class
Race Condition
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

Creates a potential deadlock in the OCFS2 filesystem driver due to circular lock acquisition order between allocation and orphan directory inodes during direct I/O completion and inode eviction.

Why it matters to the business

Can cause system hangs or crashes on systems using the OCFS2 clustered filesystem under concurrent direct I/O and file deletion workloads, leading to service disruption and potential data unavailability.

How an attack unfolds

An attacker with local access triggers the deadlock by performing direct I/O writes whose completion path acquires extent allocation locks before orphan directory locks, while concurrent inode removal acquires the locks in the reverse order.

How to fix it

Update the Linux kernel to a version containing the fix that releases allocation contexts before acquiring the orphan directory lock inside ocfs2_dio_end_io_write.

How to confirm the fix worked

Confirm the patch is present by inspecting the ocfs2_dio_end_io_write function for release of extent allocation contexts prior to the call to ocfs2_del_inode_from_orphan, and verify absence of the lockdep cycle warning involving the three system inodes.

Typical attack path

  1. Obtain local shell access on a host using OCFS2
  2. Issue direct I/O writes to files while concurrently deleting or evicting inodes
  3. Force the kernel to follow the circular lock acquisition path leading to deadlock

How to detect it

Inspect kernel logs for lockdep warnings that reference ocfs2_sysfile_lock_key combined with INODE_ALLOC_SYSTEM_INODE, EXTENT_ALLOC_SYSTEM_INODE, and ORPHAN_DIR_SYSTEM_INODE; search dmesg and syslog for the exact chain messages shown in the advisory.

What your security team should do

  • Apply the upstream kernel fix as soon as it is available in distribution packages
  • Enable lockdep and monitor kernel logs for ocfs2 circular locking warnings
  • Restrict use of OCFS2 on systems where direct I/O and frequent file lifecycle operations occur together

The record

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix circular locking dependency in ocfs2_dio_end_io_write A circular locking dependency involves INODE_ALLOC_SYSTEM_INODE, EXTENT_ALLOC_SYSTEM_INODE, and ORPHAN_DIR_SYSTEM_INODE. 1. ocfs2_mknod() acquires INODE_ALLOC then EXTENT_ALLOC. 2. ocfs2_dio_end_io_write() acquires EXTENT_ALLOC for unwritten extents, then ORPHAN_DIR via ocfs2_del_inode_from_orphan() while still holding EXTENT_ALLOC. 3. ocfs2_wipe_inode() acquires ORPHAN_DIR then INODE_ALLOC via ocfs2_remove_inode. Break the cycle in ocfs2_dio_end_io_write() by freeing the allocation contexts (releasing EXTENT_ALLOC) before acquiring ORPHAN_DIR. WARNING: possible circular locking dependency detected ------------------------------------------------------ is trying to acquire lock: ffff8881e78b33a0 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_evict_inode+0x1539/0x43b0 fs/ocfs2/inode.c:1299 but task is already holding lock: ffff8881e78b4fa0 (&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_evict_inode+0xe97/0x43b0 fs/ocfs2/inode.c:1299 the existing dependency chain (in reverse order) is: -> #2 (&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]){+.+.}-{4:4}: inode_lock include/linux/fs.h:1029 [inline] ocfs2_del_inode_from_orphan+0x12e/0x7a0 fs/ocfs2/namei.c:2728 ocfs2_dio_end_io+0xf9c/0x1370 fs/ocfs2/aops.c:2418 dio_complete+0x25b/0x790 fs/direct-io.c:281 -> #1 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}: inode_lock include/linux/fs.h:1029 [inline] ocfs2_reserve_suballoc_bits+0x16d/0x4840 fs/ocfs2/suballoc.c:882 ocfs2_reserve_new_metadata_blocks+0x415/0x9a0 fs/ocfs2/suballoc.c:1078 ocfs2_mknod+0x10f3/0x2260 fs/ocfs2/namei.c:351 -> #0 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}: __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 down_write+0x96/0x200 kernel/locking/rwsem.c:1625 inode_lock include/linux/fs.h:1029 [inline] ocfs2_remove_inode fs/ocfs2/inode.c:733 [inline] ocfs2_wipe_inode fs/ocfs2/inode.c:896 [inline] ocfs2_delete_inode fs/ocfs2/inode.c:1157 [inline] ocfs2_evict_inode+0x1539/0x43b0 fs/ocfs2/inode.c:1299 Chain exists of: &ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE] --> &ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE] --> &ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]); lock(&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]); lock(&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]); lock(&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]); *** DEADLOCK ***

Affected packages

Ecosystem Package Introduced Fixed