CVE-2025-39759: btrfs: qgroup: fix race between quota disable and quota rescan ioctl
btrfs: qgroup: fix race between quota disable and quota rescan ioctl
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.104.2-1 - Configuration
Fix the race by taking fs_info->qgroup_lock at btrfs_free_qgroup_config() so qgroup records are freed while holding fs_info->qgroup_lock (preventing use-after-free with concurrent quota rescan).
Linux kernel (btrfs) Locking in btrfs_free_qgroup_config() = Take fs_info->qgroup_lock while freeing qgroup records in btrfs_free_qgroup_config()
Event History
Frequently Asked Questions
What is the severity of CVE-2025-39759?
CVE-2025-39759 is classified as a medium severity vulnerability due to its potential for causing a use-after-free condition.
How do I fix CVE-2025-39759?
To fix CVE-2025-39759, update your Linux kernel to the latest stable release where the vulnerability has been addressed.
Which versions of the Linux kernel are affected by CVE-2025-39759?
CVE-2025-39759 affects versions of the Linux kernel prior to the patch that resolves the issue, so it is important to consult the latest updates.
What are the potential impacts of CVE-2025-39759?
The potential impact of CVE-2025-39759 includes system instability or crashes due to a race condition in the btrfs quota management.
Is CVE-2025-39759 specific to certain distributions of Linux?
CVE-2025-39759 is related to the Linux kernel itself and can affect any Linux distribution using the vulnerable kernel version.