In the Linux kernel, the following vulnerability has been resolved:
btrfs: qgroup: fix race between quota disable and quota rescan ioctl
There's a race between a task disabling quotas and another running the
rescan ioctl that can result in a use-after-free of qgroup records from
the fs_info->qgroup_tree rbtree.
This happens as follows:
1) Task A enters btrfs_ioctl_quota_rescan() -> btrfs_qgroup_rescan();
2) Task B enters btrfs_quota_disable() and calls
btrfs_qgroup_wait_for_completion(), which does nothing because at that
point fs_info->qgroup_rescan_running is false (it wasn't set yet by
task A);
3) Task B calls btrfs_free_qgroup_config() which starts freeing qgroups
from fs_info->qgroup_tree without taking the lock fs_info->qgroup_lock;
4) Task A enters qgroup_rescan_zero_tracking() which starts iterating
the fs_info->qgroup_tree tree while holding fs_info->qgroup_lock,
but task B is freeing qgroup records from that tree without holding
the lock, resulting in a use-after-free.
Fix this by taking fs_info->qgroup_lock at btrfs_free_qgroup_config().
Also at btrfs_qgroup_rescan() don't start the rescan worker if quotas
were already disabled.
References
Configurations
Configuration 1 (hide)
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Configuration 2 (hide)
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History
09 Jan 2026, 18:46
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | CWE-362 | |
| CPE | cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
|
| First Time |
Linux
Debian Debian debian Linux Linux linux Kernel |
|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.0 |
| References | () https://git.kernel.org/stable/c/2fd0f5ceb997f90f4332ccbab6c7e907e6b2d0eb - Patch | |
| References | () https://git.kernel.org/stable/c/7cda0fdde5d9890976861421d207870500f9aace - Patch | |
| References | () https://git.kernel.org/stable/c/b172535ccba12f0cf7d23b3b840989de47fc104d - Patch | |
| References | () https://git.kernel.org/stable/c/c38028ce0d0045ca600b6a8345a0ff92bfb47b66 - Patch | |
| References | () https://git.kernel.org/stable/c/dd0b28d877b293b1d7f8727a7de08ae36b6b9ef0 - Patch | |
| References | () https://git.kernel.org/stable/c/e1249667750399a48cafcf5945761d39fa584edf - Patch | |
| References | () https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html - Third Party Advisory, Mailing List |
03 Nov 2025, 18:16
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
11 Sep 2025, 17:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2025-09-11 17:15
Updated : 2026-01-09 18:46
NVD link : CVE-2025-39759
Mitre link : CVE-2025-39759
CVE.ORG link : CVE-2025-39759
JSON object : View
Products Affected
debian
- debian_linux
linux
- linux_kernel
CWE
CWE-362
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')