VulnerabilityPublished 24 Sep 2026Updated 19 Oct 2026

CVE-2026-93252: Linux kernel · ocfs2: fix circular locking dependency in ocfs2_init_acl()

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in f8747d81aa6d3efe3ee339a9d912ff3ca6e4d758 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 12:55 UTC

Severity

Unrated

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in f8747d81aa6d3efe3ee339a9d912ff3ca6e4d758, caf3056936fb8b5ce92e419cf8b246ce9c437343, bd7c05fb4a4776dff5a87b19008d28458647d15d +9

Exploitation evidence

Disclosed: evidence found.
CVE published 24 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected >=3.18.111 <3.19 >=4.4.134 <4.5 >=4.9.104 <4.10 >=4.14.37 <4.15	Fixed in f8747d81aa6d3efe3ee339a9d912ff3ca6e4d758 caf3056936fb8b5ce92e419cf8b246ce9c437343 bd7c05fb4a4776dff5a87b19008d28458647d15d 8931403ee3dcfe8a24a5267efec9d9460ab7a1b5 4936d4464d1ae10b5fbba64374085a0dcc060560 1222f7a3183b35c0c566899fdaead5c7c4043076 8d88f52fbbbcc18adf4091a955511d0cf605bf11 5b7b3c50c39ad0dc27e7418981e01c4183273f89 4.15 4.10 4.5 3.19
LinuxLinux	Affected =4.16	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix circular locking dependency in ocfs2_init_acl() A lockdep warning indicates a circular locking dependency between `&oi->ip_xattr_sem` and `&journal->j_trans_barrier`: WARNING: possible circular locking dependency detected is trying to acquire lock: (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_init_acl+0x2fd/0x7e0 fs/ocfs2/acl.c:367 but task is already holding lock: (&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3ab/0x700 fs/ocfs2/journal.c:369 The deadlock involves two code paths: Path 1 (setxattr) where `ocfs2_xattr_set()` acquires `ip_xattr_sem` (write) and then starts a transaction, which acquires `j_trans_barrier` (read); and Path 2 (mkdir/mknod) where `ocfs2_mknod()` starts a transaction (`j_trans_barrier` read) and then calls `ocfs2_init_acl()`, which attempts to acquire `ip_xattr_sem` (read) on the parent directory to retrieve the default ACL. Because rw_semaphores are subject to writer priority, a pending writer on `j_trans_barrier` (e.g., the journal commit thread) can cause Path 1 to block, while Path 2 is blocked waiting for Path 1 to release `ip_xattr_sem`. The patch fixes the lock ordering by precomputing the ACL state before starting the OCFS2 transaction, while preserving POSIX ACL storage semantics and the existing inode/security initialization order. By reading the parent directory's default ACL and preparing the new inode's ACLs outside the transaction, `ip_xattr_sem` is always acquired before `j_trans_barrier`. `struct ocfs2_acl_state` encapsulates the prepared ACL state, while `ocfs2_acl_init_prepare()` and `ocfs2_acl_init_release()` avoid code duplication between `ocfs2_mknod()` and `ocfs2_init_security_and_acl()`. `ocfs2_calc_xattr_init()` and `ocfs2_init_acl()` use this precomputed state, removing internal `ip_xattr_sem` acquisition and redundant disk reads. Additionally, remove the `ip_xattr_sem` acquisition from `ocfs2_xattr_set_handle()`. This function is only used while initializing a new inode that has not yet been inserted into the inode hash or attached to a dentry, meaning there is no risk of concurrent access and the lock is unnecessary.

References

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