# CVE-2024-43914: md/raid5: avoid BUG_ON() while continue reshape after reassembling

> A local attacker can trigger a kernel panic in the Linux RAID5 subsystem during array reassembly, causing a denial of service.

- **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:** 26 Aug 2024
- **Updated:** 11 May 2026
- **Also known as:** AZL-48617, BELL-CVE-2024-43914, DEBIAN-CVE-2024-43914, GHSA-j2jm-9cr2-x48x, UBUNTU-CVE-2024-43914

## What is CVE-2024-43914?

CVE-2024-43914 is a medium-severity denial of service vulnerability in Linux kernel, published on 26 Aug 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:

md/raid5: avoid BUG_ON() while continue reshape after reassembling

Currently, mdadm support --revert-reshape to abort the reshape while
reassembling, as the test 07revert-grow. However, following BUG_ON()
can be triggerred by the test:

kernel BUG at drivers/md/raid5.c:6278!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
irq event stamp: 158985
CPU: 6 PID: 891 Comm: md0_reshape Not tainted 6.9.0-03335-g7592a0b0049a #94
RIP: 0010:reshape_request+0x3f1/0xe60
Call Trace:
 <TASK>
 raid5_sync_request+0x43d/0x550
 md_do_sync+0xb7a/0x2110
 md_thread+0x294/0x2b0
 kthread+0x147/0x1c0
 ret_from_fork+0x59/0x70
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Root cause is that --revert-reshape update the raid_disks from 5 to 4,
while reshape position is still set, and after reassembling the array,
reshape position will be read from super block, then during reshape the
checking of 'writepos' that is caculated by old reshape position will
fail.

Fix this panic the easy way first, by converting the BUG_ON() to
WARN_ON(), and stop the reshape if checkings fail.

Noted that mdadm must fix --revert-shape as well, and probably md/raid
should enhance metadata validation as well, however this means
reassemble will fail and there must be user tools to fix the wrong
metadata.

## Which versions are affected by CVE-2024-43914?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-43914?

Apply the vendor's patch.

## Is CVE-2024-43914 being exploited?

There is no known exploitation of CVE-2024-43914 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-2024-43914 and fix it if it is affected.

What it is: CVE-2024-43914 is a medium-severity denial of service vulnerability in Linux kernel, published on 26 Aug 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-2024-43914 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-2024-43914/ (Markdown: https://insights.sbomify.com/CVE-2024-43914/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-43914
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-43914
- OSV: https://osv.dev/vulnerability/CVE-2024-43914

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-43914/
Summaries are generated and may contain mistakes; the official description above is the record.
