# CVE-2024-56566: mm/slub: Avoid list corruption when removing a slab from the full list

> A list corruption bug in the Linux kernel SLUB allocator causes a kernel panic when debug checks fail, leading to 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:** 27 Dec 2024
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2024-56566, DEBIAN-CVE-2024-56566, GHSA-xqjf-h57w-hh6f, ROOT-OS-DEBIAN-11-CVE-2024-56566, ROOT-OS-DEBIAN-12-CVE-2024-56566, ROOT-OS-UBUNTU-2204-CVE-2024-56566, UBUNTU-CVE-2024-56566

## What is CVE-2024-56566?

CVE-2024-56566 is a medium-severity memory corruption 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:

mm/slub: Avoid list corruption when removing a slab from the full list

Boot with slub_debug=UFPZ.

If allocated object failed in alloc_consistency_checks, all objects of
the slab will be marked as used, and then the slab will be removed from
the partial list.

When an object belonging to the slab got freed later, the remove_full()
function is called. Because the slab is neither on the partial list nor
on the full list, it eventually lead to a list corruption (actually a
list poison being detected).

So we need to mark and isolate the slab page with metadata corruption,
do not put it back in circulation.

Because the debug caches avoid all the fastpaths, reusing the frozen bit
to mark slab page with metadata corruption seems to be fine.

[ 4277.385669] list_del corruption, ffffea00044b3e50->next is LIST_POISON1 (dead000000000100)
[ 4277.387023] ------------[ cut here ]------------
[ 4277.387880] kernel BUG at lib/list_debug.c:56!
[ 4277.388680] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[ 4277.389562] CPU: 5 PID: 90 Comm: kworker/5:1 Kdump: loaded Tainted: G           OE      6.6.1-1 #1
[ 4277.392113] Workqueue: xfs-inodegc/vda1 xfs_inodegc_worker [xfs]
[ 4277.393551] RIP: 0010:__list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.394518] Code: 48 91 82 e8 37 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 28 49 91 82 e8 26 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 58 49 91
[ 4277.397292] RSP: 0018:ffffc90000333b38 EFLAGS: 00010082
[ 4277.398202] RAX: 000000000000004e RBX: ffffea00044b3e50 RCX: 0000000000000000
[ 4277.399340] RDX: 0000000000000002 RSI: ffffffff828f8715 RDI: 00000000ffffffff
[ 4277.400545] RBP: ffffea00044b3e40 R08: 0000000000000000 R09: ffffc900003339f0
[ 4277.401710] R10: 0000000000000003 R11: ffffffff82d44088 R12: ffff888112cf9910
[ 4277.402887] R13: 0000000000000001 R14: 0000000000000001 R15: ffff8881000424c0
[ 4277.404049] FS:  0000000000000000(0000) GS:ffff88842fd40000(0000) knlGS:0000000000000000
[ 4277.405357] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4277.406389] CR2: 00007f2ad0b24000 CR3: 0000000102a3a006 CR4: 00000000007706e0
[ 4277.407589] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 4277.408780] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 4277.410000] PKRU: 55555554
[ 4277.410645] Call Trace:
[ 4277.411234]  <TASK>
[ 4277.411777]  ? die+0x32/0x80
[ 4277.412439]  ? do_trap+0xd6/0x100
[ 4277.413150]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.414158]  ? do_error_trap+0x6a/0x90
[ 4277.414948]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.415915]  ? exc_invalid_op+0x4c/0x60
[ 4277.416710]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.417675]  ? asm_exc_invalid_op+0x16/0x20
[ 4277.418482]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.419466]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.420410]  free_to_partial_list+0x515/0x5e0
[ 4277.421242]  ? xfs_iext_remove+0x41a/0xa10 [xfs]
[ 4277.422298]  xfs_iext_remove+0x41a/0xa10 [xfs]
[ 4277.423316]  ? xfs_inodegc_worker+0xb4/0x1a0 [xfs]
[ 4277.424383]  xfs_bmap_del_extent_delay+0x4fe/0x7d0 [xfs]
[ 4277.425490]  __xfs_bunmapi+0x50d/0x840 [xfs]
[ 4277.426445]  xfs_itruncate_extents_flags+0x13a/0x490 [xfs]
[ 4277.427553]  xfs_inactive_truncate+0xa3/0x120 [xfs]
[ 4277.428567]  xfs_inactive+0x22d/0x290 [xfs]
[ 4277.429500]  xfs_inodegc_worker+0xb4/0x1a0 [xfs]
[ 4277.430479]  process_one_work+0x171/0x340
[ 4277.431227]  worker_thread+0x277/0x390
[ 4277.431962]  ? __pfx_worker_thread+0x10/0x10
[ 4277.432752]  kthread+0xf0/0x120
[ 4277.433382]  ? __pfx_kthread+0x10/0x10
[ 4277.434134]  ret_from_fork+0x2d/0x50
[ 4277.434837]  ? __pfx_kthread+0x10/0x10
[ 4277.435566]  ret_from_fork_asm+0x1b/0x30
[ 4277.436280]  </TASK>

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2024-56566?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-56566?

Apply the vendor's patch.

## Is CVE-2024-56566 being exploited?

There is no known exploitation of CVE-2024-56566 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-2024-56566 and fix it if it is affected.

What it is: CVE-2024-56566 is a medium-severity memory corruption 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-2024-56566 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-2024-56566/ (Markdown: https://insights.sbomify.com/CVE-2024-56566/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-56566
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-56566
- OSV: https://osv.dev/vulnerability/CVE-2024-56566

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-56566/
Summaries are generated and may contain mistakes; the official description above is the record.
