# CVE-2024-53221: f2fs: fix null-ptr-deref in f2fs_submit_page_bio()

> A null pointer dereference in the Linux kernel f2fs module can cause a system crash during concurrent module installation and filesystem mounting.

- **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:** 27 Dec 2024
- **Updated:** 1 Jun 2026
- **Also known as:** BELL-CVE-2024-53221, DEBIAN-CVE-2024-53221, GHSA-376g-f56r-v5h4, ROOT-OS-DEBIAN-11-CVE-2024-53221, ROOT-OS-DEBIAN-12-CVE-2024-53221, ROOT-OS-UBUNTU-2204-CVE-2024-53221, UBUNTU-CVE-2024-53221

## What is CVE-2024-53221?

CVE-2024-53221 is a medium-severity vulnerability in Linux kernel, published on 27 Dec 2024. 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:

f2fs: fix null-ptr-deref in f2fs_submit_page_bio()

There's issue as follows when concurrently installing the f2fs.ko
module and mounting the f2fs file system:
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
RIP: 0010:__bio_alloc+0x2fb/0x6c0 [f2fs]
Call Trace:
 <TASK>
 f2fs_submit_page_bio+0x126/0x8b0 [f2fs]
 __get_meta_page+0x1d4/0x920 [f2fs]
 get_checkpoint_version.constprop.0+0x2b/0x3c0 [f2fs]
 validate_checkpoint+0xac/0x290 [f2fs]
 f2fs_get_valid_checkpoint+0x207/0x950 [f2fs]
 f2fs_fill_super+0x1007/0x39b0 [f2fs]
 mount_bdev+0x183/0x250
 legacy_get_tree+0xf4/0x1e0
 vfs_get_tree+0x88/0x340
 do_new_mount+0x283/0x5e0
 path_mount+0x2b2/0x15b0
 __x64_sys_mount+0x1fe/0x270
 do_syscall_64+0x5f/0x170
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Above issue happens as the biset of the f2fs file system is not
initialized before register "f2fs_fs_type".
To address above issue just register "f2fs_fs_type" at the last in
init_f2fs_fs(). Ensure that all f2fs file system resources are
initialized.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2024-53221?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53221?

Apply the vendor's patch.

## Is CVE-2024-53221 being exploited?

There is no known exploitation of CVE-2024-53221 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-2024-53221 and fix it if it is affected.

What it is: CVE-2024-53221 is a medium-severity vulnerability in Linux kernel, published on 27 Dec 2024. 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-2024-53221 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-2024-53221/ (Markdown: https://insights.sbomify.com/CVE-2024-53221/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53221
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53221
- OSV: https://osv.dev/vulnerability/CVE-2024-53221

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53221/
Summaries are generated and may contain mistakes; the official description above is the record.