LiveActive security incident?Get immediate response
CVE Record

CVE-2025-23132: f2fs: quota: fix to avoid warning in dquot_writeback_dquots()

In the Linux kernel, the following vulnerability has been resolved: f2fs: quota: fix to avoid warning in dquot_writeback_dquots() F2FS-fs (dm-59): checkpoint=enable has some unwritten data. ------------[ cut here ]------------ WARNING: CPU: 6 PID: 8013 at fs/quota/dquot.c:691 dquot_writeback_dquots+0x2fc/0x308 pc : dquot_writeback_dquots+0x2fc/0x308 lr : f2fs_quota_sync+0xcc/0x1c4 Call trace: dquot_writeback_dquots+0x2fc/0x308 f2fs_quota_sync+0xcc/0x1c4 f2fs_write_checkpoint+0x3d4/0x9b0 f2fs_issue_checkpoint+0x1bc/0x2c0 f2fs_sync_fs+0x54/0x150 f2fs_do_sync_file+0x2f8/0x814 __f2fs_ioctl+0x1960/0x3244 f2fs_ioctl+0x54/0xe0 __arm64_sys_ioctl+0xa8/0xe4 invoke_syscall+0x58/0x114 checkpoint and f2fs_remount may race as below, resulting triggering warning in dquot_writeback_dquots(). atomic write remount - do_remount - down_write(&sb->s_umount); - f2fs_remount - ioctl - f2fs_do_sync_file - f2fs_sync_fs - f2fs_write_checkpoint - block_operations - locked = down_read_trylock(&sbi->sb->s_umount) : fail to lock due to the write lock was held by remount - up_write(&sb->s_umount); - f2fs_quota_sync - dquot_writeback_dquots - WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount)) : trigger warning because s_umount lock was unlocked by remount If checkpoint comes from mount/umount/remount/freeze/quotactl, caller of checkpoint has already held s_umount lock, calling dquot_writeback_dquots() in the context should be safe. So let's record task to sbi->umount_lock_holder, so that checkpoint can know whether the lock has held in the context or not by checking current w/ it. In addition, in order to not misrepresent caller of checkpoint, we should not allow to trigger async checkpoint for those callers: mount/umount/remount/ freeze/quotactl.

HighCVSS 7Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

A race in Linux F2FS quota checkpoint handling can trigger a kernel warning when filesystem checkpoint activity overlaps a remount. The supplied rating is high, but the technical description demonstrates a warning rather than a confirmed path to data theft, modification, or system takeover.

Executive priority

Treat this as a targeted high-priority kernel maintenance issue, not an internet-wide emergency. Identify F2FS-dependent systems first, confirm vendor fix status, and schedule supported kernel updates. Escalate faster where kernel warnings, frequent remounts, or sensitive F2FS workloads are present.

Technical view

CVE-2025-23132 occurs when F2FS checkpoint processing fails to retain the expected s_umount lock while racing with remount. Quota writeback then reaches a WARN_ON_ONCE condition. The kernel fix records the lock-holding task and prevents asynchronous checkpoints for mount, unmount, remount, freeze, and quotactl callers.

Likely exposure

Exposure is limited to affected Linux kernels using F2FS in the relevant quota and checkpoint conditions. The supplied affected data identifies versions from 4.20 through 6.14.2, with 6.15 also listed, but distributions may carry backported fixes; verify vendor packages individually.

Exploitation context

The CVSS vector describes local access, low privileges, high attack complexity, no user interaction, and potentially high confidentiality, integrity, and availability impact. No CISA KEV listing or active-exploitation evidence is supplied. The source description establishes a race-triggered kernel warning, not a demonstrated practical exploit.

Researcher notes

The vulnerable condition involves f2fs_write_checkpoint, f2fs_quota_sync, and dquot_writeback_dquots during contention on sb->s_umount. The supplied record lacks CWE classification and proof of exploitation. Researchers should distinguish the CVSS-assessed worst-case impact from the directly documented WARN_ON_ONCE behavior.

Mitigation direction

  • Apply a vendor-supported kernel containing the referenced upstream or stable fix.
  • Check distribution advisories for backports before relying solely on displayed kernel versions.
  • Prioritize systems that actively use F2FS with quotas or checkpoint-sensitive workloads.
  • Follow vendor guidance if immediate kernel replacement is operationally impractical.

Validation and detection

  • Inventory hosts, kernel package versions, and whether F2FS filesystems are mounted.
  • Determine whether F2FS quotas and affected checkpoint or remount workflows are used.
  • Confirm the vendor kernel includes either referenced fix or an equivalent backport.
  • Review kernel logs for the documented dquot_writeback_dquots warning and F2FS checkpoint messages.
Prepared
Confidence
medium
Sources
4

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2025-23132 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
7 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
3Timeline events
0ADP providers
3Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7CVSS 3.1HighCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H15.9Linux

Vulnerability scoring details

Base CVSS 3.1 score

7High
CVSS 3.1 vector shape for CVE-2025-23132Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxaf033b2aa8a874fd5737fafe90d159136527b5b4, af033b2aa8a874fd5737fafe90d159136527b5b4unaffected
LinuxLinux4.20, 0, 6.14.2, 6.15affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.