CVE-2026-53050
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk3th percentile — higher than 3% of all known CVEs
Summary
A race condition in the Linux kernel's dquot_scan_active() function during quota deactivation can lead to use-after-free, potentially causing system instability.
Risk Assessment
The risk includes potential data corruption or kernel panic due to accessing freed memory structures, especially under memory pressure.
Recommendation
Immediately update the Linux kernel to a version containing the fix that resolves the race condition in the quota subsystem.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: quota: Fix race of dquot_scan_active() with quota deactivation dquot_scan_active() can race with quota deactivation in quota_release_workfn() like: CPU0 (quota_release_workfn) CPU1 (dquot_scan_active) ============================== ============================== spin_lock(&dq_list_lock); list_replace_init( &releasing_dquots, &rls_head); /* dquot X on rls_head, dq_count == 0, DQ_ACTIVE_B still set */ spin_unlock(&dq_list_lock); synchronize_srcu(&dquot_srcu); spin_lock(&dq_list_lock); list_for_each_entry(dquot, &inuse_list, dq_inuse) { /* finds dquot X */ dquot_active(X) -> true atomic_inc(&X->dq_count); } spin_unlock(&dq_list_lock); spin_lock(&dq_list_lock); dquot = list_first_entry(&rls_head); WARN_ON_ONCE(atomic_read(&dquot->dq_count)); The problem is not only a cosmetic one as under memory pressure the caller of dquot_scan_active() can end up working on freed dquot. Fix the problem by making sure the dquot is removed from releasing list when we acquire a reference to it.