CVE-2026-31598
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix possible deadlock between unlink and dio_end_io_write ocfs2_unlink takes orphan dir inode_lock first and then ip_alloc_sem, while in ocfs2_dio_end_io_write, it acquires these locks in reverse order. This creates an ABBA lock ordering violation on lock classes ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE] and ocfs2_file_ip_alloc_sem_key. Lock Chain #0 (orphan dir inode_lock -> ip_alloc_sem): ocfs2_unlink ocfs2_prepare_orphan_dir ocfs2_lookup_lock_orphan_dir inode_lock(orphan_dir_inode) <- lock A __ocfs2_prepare_orphan_dir ocfs2_prepare_dir_for_insert ocfs2_extend_dir ocfs2_expand_inline_dir down_write(&oi->ip_alloc_sem) <- Lock B Lock Chain #1 (ip_alloc_sem -> orphan dir inode_lock): ocfs2_dio_end_io_write down_write(&oi->ip_alloc_sem) <- Lock B ocfs2_del_inode_from_orphan() inode_lock(orphan_dir_inode) <- Lock A Deadlock Scenario: CPU0 (unlink) CPU1 (dio_end_io_write) ------ ------ inode_lock(orphan_dir_inode) down_write(ip_alloc_sem) down_write(ip_alloc_sem) inode_lock(orphan_dir_inode) Since ip_alloc_sem is to protect allocation changes, which is unrelated with operations in ocfs2_del_inode_from_orphan. So move ocfs2_del_inode_from_orphan out of ip_alloc_sem to fix the deadlock.
EPSS 0.07% · 21.3th percentile
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | *, 6.12.83, 6.18.24 |
| linux | linux_kernel | 0, 0, 0 |
Timeline
- Apr 24, 2026 CVE Published
- Apr 24, 2026 Security Advisory
- Apr 27, 2026 Security Advisory
- Apr 27, 2026 CVE Updated
- May 18, 2026 EPSS Score
- May 19, 2026 EPSS Score
- May 20, 2026 EPSS Score
- May 21, 2026 EPSS Score
- May 22, 2026 EPSS Score
- May 23, 2026 EPSS Score
- May 24, 2026 EPSS Score
- May 25, 2026 EPSS Score
References
- https://git.kernel.org/stable/c/2b884d52273c60c298bd570163e8053657bbaff6 url
- https://git.kernel.org/stable/c/bc0fb5c7d54c78be43a536df0e20dee32adb27d3 url
- https://git.kernel.org/stable/c/f9fb1a7b635849322e1d7b7b6b26389778ec8e82 url
- https://git.kernel.org/stable/c/e049f7a9bd80b7319590789ea5e1c523d6339d91 url
- https://nvd.nist.gov/vuln/detail/CVE-2026-31598 advisory
- https://lists.debian.org/debian-security-announce/2026/msg00154.html advisory
- https://lists.debian.org/debian-security-announce/2026/msg00148.html advisory