# CVE-2024-57806: btrfs: fix transaction atomicity bug when enabling simple quotas

> A local attacker can cause a kernel crash by mounting a Btrfs filesystem with simple quotas enabled, requiring CONFIG_BTRFS_ASSERT to be active.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Jan 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2024-57806, DEBIAN-CVE-2024-57806, GHSA-ffjg-532q-8rr8, UBUNTU-CVE-2024-57806

## What is CVE-2024-57806?

CVE-2024-57806 is a medium-severity denial of service vulnerability in Linux kernel, published on 11 Jan 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix transaction atomicity bug when enabling simple quotas

Set squota incompat bit before committing the transaction that enables
the feature.

With the config CONFIG_BTRFS_ASSERT enabled, an assertion
failure occurs regarding the simple quota feature.

  [5.596534] assertion failed: btrfs_fs_incompat(fs_info, SIMPLE_QUOTA), in fs/btrfs/qgroup.c:365
  [5.597098] ------------[ cut here ]------------
  [5.597371] kernel BUG at fs/btrfs/qgroup.c:365!
  [5.597946] CPU: 1 UID: 0 PID: 268 Comm: mount Not tainted 6.13.0-rc2-00031-gf92f4749861b #146
  [5.598450] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  [5.599008] RIP: 0010:btrfs_read_qgroup_config+0x74d/0x7a0
  [5.604303]  <TASK>
  [5.605230]  ? btrfs_read_qgroup_config+0x74d/0x7a0
  [5.605538]  ? exc_invalid_op+0x56/0x70
  [5.605775]  ? btrfs_read_qgroup_config+0x74d/0x7a0
  [5.606066]  ? asm_exc_invalid_op+0x1f/0x30
  [5.606441]  ? btrfs_read_qgroup_config+0x74d/0x7a0
  [5.606741]  ? btrfs_read_qgroup_config+0x74d/0x7a0
  [5.607038]  ? try_to_wake_up+0x317/0x760
  [5.607286]  open_ctree+0xd9c/0x1710
  [5.607509]  btrfs_get_tree+0x58a/0x7e0
  [5.608002]  vfs_get_tree+0x2e/0x100
  [5.608224]  fc_mount+0x16/0x60
  [5.608420]  btrfs_get_tree+0x2f8/0x7e0
  [5.608897]  vfs_get_tree+0x2e/0x100
  [5.609121]  path_mount+0x4c8/0xbc0
  [5.609538]  __x64_sys_mount+0x10d/0x150

The issue can be easily reproduced using the following reproducer:

  root@q:linux# cat repro.sh
  set -e

  mkfs.btrfs -q -f /dev/sdb
  mount /dev/sdb /mnt/btrfs
  btrfs quota enable -s /mnt/btrfs
  umount /mnt/btrfs
  mount /dev/sdb /mnt/btrfs

The issue is that when enabling quotas, at btrfs_quota_enable(), we set
BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE at fs_info->qgroup_flags and persist
it in the quota root in the item with the key BTRFS_QGROUP_STATUS_KEY, but
we only set the incompat bit BTRFS_FEATURE_INCOMPAT_SIMPLE_QUOTA after we
commit the transaction used to enable simple quotas.

This means that if after that transaction commit we unmount the filesystem
without starting and committing any other transaction, or we have a power
failure, the next time we mount the filesystem we will find the flag
BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE set in the item with the key
BTRFS_QGROUP_STATUS_KEY but we will not find the incompat bit
BTRFS_FEATURE_INCOMPAT_SIMPLE_QUOTA set in the superblock, triggering an
assertion failure at:

  btrfs_read_qgroup_config() -> qgroup_read_enable_gen()

To fix this issue, set the BTRFS_FEATURE_INCOMPAT_SIMPLE_QUOTA flag
immediately after setting the BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE.
This ensures that both flags are flushed to disk within the same
transaction.

Weakness: CWE-617 (Reachable Assertion)

## Which versions are affected by CVE-2024-57806?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-57806?

Apply the vendor's patch.

## Is CVE-2024-57806 being exploited?

There is no known exploitation of CVE-2024-57806 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-57806 and fix it if it is affected.

What it is: CVE-2024-57806 is a medium-severity denial of service vulnerability in Linux kernel, published on 11 Jan 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-57806 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-57806/ (Markdown: https://insights.sbomify.com/CVE-2024-57806/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-57806
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-57806
- OSV: https://osv.dev/vulnerability/CVE-2024-57806

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-57806/
Summaries are generated and may contain mistakes; the official description above is the record.