# CVE-2023-52808: scsi: hisi_sas: Set debugfs_dir pointer to NULL after removing debugfs

> A null pointer dereference in the hisi_sas driver causes a kernel crash when debugfs initialization fails and the device is subsequently removed.

- **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:** 21 May 2024
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2023-52808, DEBIAN-CVE-2023-52808, GHSA-8r5m-pqvh-q2vm, ROOT-OS-DEBIAN-11-CVE-2023-52808, UBUNTU-CVE-2023-52808

## What is CVE-2023-52808?

CVE-2023-52808 is a medium-severity vulnerability in Linux kernel, published on 21 May 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:

scsi: hisi_sas: Set debugfs_dir pointer to NULL after removing debugfs

If init debugfs failed during device registration due to memory allocation
failure, debugfs_remove_recursive() is called, after which debugfs_dir is
not set to NULL. debugfs_remove_recursive() will be called again during
device removal. As a result, illegal pointer is accessed.

[ 1665.467244] hisi_sas_v3_hw 0000:b4:02.0: failed to init debugfs!
...
[ 1669.836708] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a0
[ 1669.872669] pc : down_write+0x24/0x70
[ 1669.876315] lr : down_write+0x1c/0x70
[ 1669.879961] sp : ffff000036f53a30
[ 1669.883260] x29: ffff000036f53a30 x28: ffffa027c31549f8
[ 1669.888547] x27: ffffa027c3140000 x26: 0000000000000000
[ 1669.893834] x25: ffffa027bf37c270 x24: ffffa027bf37c270
[ 1669.899122] x23: ffff0000095406b8 x22: ffff0000095406a8
[ 1669.904408] x21: 0000000000000000 x20: ffffa027bf37c310
[ 1669.909695] x19: 00000000000000a0 x18: ffff8027dcd86f10
[ 1669.914982] x17: 0000000000000000 x16: 0000000000000000
[ 1669.920268] x15: 0000000000000000 x14: ffffa0274014f870
[ 1669.925555] x13: 0000000000000040 x12: 0000000000000228
[ 1669.930842] x11: 0000000000000020 x10: 0000000000000bb0
[ 1669.936129] x9 : ffff000036f537f0 x8 : ffff80273088ca10
[ 1669.941416] x7 : 000000000000001d x6 : 00000000ffffffff
[ 1669.946702] x5 : ffff000008a36310 x4 : ffff80273088be00
[ 1669.951989] x3 : ffff000009513e90 x2 : 0000000000000000
[ 1669.957276] x1 : 00000000000000a0 x0 : ffffffff00000001
[ 1669.962563] Call trace:
[ 1669.965000]  down_write+0x24/0x70
[ 1669.968301]  debugfs_remove_recursive+0x5c/0x1b0
[ 1669.972905]  hisi_sas_debugfs_exit+0x24/0x30 [hisi_sas_main]
[ 1669.978541]  hisi_sas_v3_remove+0x130/0x150 [hisi_sas_v3_hw]
[ 1669.984175]  pci_device_remove+0x48/0xd8
[ 1669.988082]  device_release_driver_internal+0x1b4/0x250
[ 1669.993282]  device_release_driver+0x28/0x38
[ 1669.997534]  pci_stop_bus_device+0x84/0xb8
[ 1670.001611]  pci_stop_and_remove_bus_device_locked+0x24/0x40
[ 1670.007244]  remove_store+0xfc/0x140
[ 1670.010802]  dev_attr_store+0x44/0x60
[ 1670.014448]  sysfs_kf_write+0x58/0x80
[ 1670.018095]  kernfs_fop_write+0xe8/0x1f0
[ 1670.022000]  __vfs_write+0x60/0x190
[ 1670.025472]  vfs_write+0xac/0x1c0
[ 1670.028771]  ksys_write+0x6c/0xd8
[ 1670.032071]  __arm64_sys_write+0x24/0x30
[ 1670.035977]  el0_svc_common+0x78/0x130
[ 1670.039710]  el0_svc_handler+0x38/0x78
[ 1670.043442]  el0_svc+0x8/0xc

To fix this, set debugfs_dir to NULL after debugfs_remove_recursive().

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2023-52808?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-52808?

Apply the vendor's patch.

## Is CVE-2023-52808 being exploited?

There is no known exploitation of CVE-2023-52808 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-2023-52808 and fix it if it is affected.

What it is: CVE-2023-52808 is a medium-severity vulnerability in Linux kernel, published on 21 May 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-2023-52808 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-2023-52808/ (Markdown: https://insights.sbomify.com/CVE-2023-52808/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-52808
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-52808
- OSV: https://osv.dev/vulnerability/CVE-2023-52808

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-52808/
Summaries are generated and may contain mistakes; the official description above is the record.