CVE-2026-31598

ocfs2: fix possible deadlock between unlink and dio_end_io_write

State: Published
Severity: 7.5 High
Published: Apr 24, 2026
Updated: Oct 19, 2026
Reserved: Mar 9, 2026

Description

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.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	Linux

Weaknesses

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Affected Products

Product	Versions
LinuxLinux	a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 297d8d7bb6a2bf133d3a3636edbdf94101cbd719Affected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 32630dee18c6bb2175c8a865a474749492eaf19cAffected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 93f35419eb84d58820040642cb6e7528fe4aba7aAffected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 4b80b5a838a32437f2cae0662578bac216a2c51aAffected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 2b884d52273c60c298bd570163e8053657bbaff6Affected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before bc0fb5c7d54c78be43a536df0e20dee32adb27d3Affected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before f9fb1a7b635849322e1d7b7b6b26389778ec8e82Affected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before e049f7a9bd80b7319590789ea5e1c523d6339d91Affected a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before b02da26a992db0c0e2559acbda0fc48d4a2fd337Affected
LinuxLinux	4.6Affected before 4.6Not affected 5.10.258 through 5.10.Not affected 5.15.209 through 5.15.Not affected 6.1.175 through 6.1.Not affected 6.6.136 through 6.6.Not affected 6.12.83 through 6.12.Not affected 6.18.24 through 6.18.Not affected 6.19.14 through 6.19.Not affected 7.0.1 through 7.0.Not affected 7.1 and laterNot affected

Product

Versions

LinuxLinux

a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 297d8d7bb6a2bf133d3a3636edbdf94101cbd719Affected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 32630dee18c6bb2175c8a865a474749492eaf19cAffected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 93f35419eb84d58820040642cb6e7528fe4aba7aAffected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 4b80b5a838a32437f2cae0662578bac216a2c51aAffected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before 2b884d52273c60c298bd570163e8053657bbaff6Affected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before bc0fb5c7d54c78be43a536df0e20dee32adb27d3Affected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before f9fb1a7b635849322e1d7b7b6b26389778ec8e82Affected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before e049f7a9bd80b7319590789ea5e1c523d6339d91Affected
a86a72a4a4e0ec109a98e2737948864ed6794bf7 to before b02da26a992db0c0e2559acbda0fc48d4a2fd337Affected

LinuxLinux

4.6Affected
before 4.6Not affected
5.10.258 through 5.10.*Not affected
5.15.209 through 5.15.*Not affected
6.1.175 through 6.1.*Not affected
6.6.136 through 6.6.*Not affected
6.12.83 through 6.12.*Not affected
6.18.24 through 6.18.*Not affected
6.19.14 through 6.19.*Not affected
7.0.1 through 7.0.*Not affected
7.1 and laterNot affected

References

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