# CVE-2024-53155: ocfs2: fix uninitialized value in ocfs2_file_read_iter()

> A local attacker can read uninitialized kernel memory via the ocfs2 file read iterator, potentially exposing sensitive data.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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:** 24 Dec 2024
- **Updated:** 11 May 2026
- **Also known as:** AZL-54993, BELL-CVE-2024-53155, DEBIAN-CVE-2024-53155, GHSA-h5xq-p424-h7cq, UBUNTU-CVE-2024-53155

## What is CVE-2024-53155?

CVE-2024-53155 is a high-severity vulnerability in Linux kernel, published on 24 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:

ocfs2: fix uninitialized value in ocfs2_file_read_iter()

Syzbot has reported the following KMSAN splat:

BUG: KMSAN: uninit-value in ocfs2_file_read_iter+0x9a4/0xf80
 ocfs2_file_read_iter+0x9a4/0xf80
 __io_read+0x8d4/0x20f0
 io_read+0x3e/0xf0
 io_issue_sqe+0x42b/0x22c0
 io_wq_submit_work+0xaf9/0xdc0
 io_worker_handle_work+0xd13/0x2110
 io_wq_worker+0x447/0x1410
 ret_from_fork+0x6f/0x90
 ret_from_fork_asm+0x1a/0x30

Uninit was created at:
 __alloc_pages_noprof+0x9a7/0xe00
 alloc_pages_mpol_noprof+0x299/0x990
 alloc_pages_noprof+0x1bf/0x1e0
 allocate_slab+0x33a/0x1250
 ___slab_alloc+0x12ef/0x35e0
 kmem_cache_alloc_bulk_noprof+0x486/0x1330
 __io_alloc_req_refill+0x84/0x560
 io_submit_sqes+0x172f/0x2f30
 __se_sys_io_uring_enter+0x406/0x41c0
 __x64_sys_io_uring_enter+0x11f/0x1a0
 x64_sys_call+0x2b54/0x3ba0
 do_syscall_64+0xcd/0x1e0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Since an instance of 'struct kiocb' may be passed from the block layer
with 'private' field uninitialized, introduce 'ocfs2_iocb_init_rw_locked()'
and use it from where 'ocfs2_dio_end_io()' might take care, i.e. in
'ocfs2_file_read_iter()' and 'ocfs2_file_write_iter()'.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2024-53155?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53155?

Apply the vendor's patch.

## Is CVE-2024-53155 being exploited?

There is no known exploitation of CVE-2024-53155 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-2024-53155 and fix it if it is affected.

What it is: CVE-2024-53155 is a high-severity vulnerability in Linux kernel, published on 24 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-2024-53155 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-2024-53155/ (Markdown: https://insights.sbomify.com/CVE-2024-53155/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53155
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53155
- OSV: https://osv.dev/vulnerability/CVE-2024-53155

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53155/
Summaries are generated and may contain mistakes; the official description above is the record.