CVE-2024-56780

What it actually does

Race condition in quota handling allows dquot_release_work to remain queued during dquot_writeback_dquots called from freeze_super/sync_filesystem, resulting in quota_release_workfn attempting ext4 journal start after SB_FREEZE_COMPLETE and hitting WARN_ON.

Why it matters to the business

Produces kernel log noise and test failures on ext4 systems with quotas during filesystem freeze; widespread in Linux environments but low operational disruption given absence from KEV and flat low EPSS trend.

How an attack unfolds

No attacker exploitation path exists; the race occurs during normal filesystem freeze operations on systems with pending quota release work and is not triggered by malicious input or threat actors.

How to fix it

Update Linux kernel to commit 2dde18cd1d8fac735875f2e4987f11817cc0bc2c or later; rebuild and deploy the patched kernel across affected systems.

How to confirm the fix worked

Verify kernel source contains the flush of quota_release_work in dquot_writeback_dquots; confirm absence of the ext4_journal_check_start WARN_ON during filesystem freeze tests.

How to detect it

Review kernel logs and dmesg for the ext4_journal_check_start WARN_ON triggered from quota_release_workfn during or after filesystem freeze; no post-exploitation artifacts exist.

What your security team should do

• Prioritize kernel upgrade to the listed fixed commit in all production Linux distributions using ext4 quotas.
• Monitor dmesg for the specific WARN_ON string during freeze operations until patches are applied.
• Include the fix in standard kernel update testing and rollout procedures.