# CVE-2025-22089: RDMA/core: Don't expose hw_counters outside of init net namespace

> A null pointer dereference in the Linux kernel RDMA subsystem allows local attackers to cause a system crash by accessing hardware counters outside the init network namespace.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 16 Apr 2025
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2025-22089, DEBIAN-CVE-2025-22089, GHSA-mh27-4q3p-7mc8, ROOT-OS-UBUNTU-2404-CVE-2025-22089, UBUNTU-CVE-2025-22089

## What is CVE-2025-22089?

CVE-2025-22089 is a high-severity vulnerability in Linux kernel, published on 16 Apr 2025. 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:

RDMA/core: Don't expose hw_counters outside of init net namespace

Commit 467f432a521a ("RDMA/core: Split port and device counter sysfs
attributes") accidentally almost exposed hw counters to non-init net
namespaces. It didn't expose them fully, as an attempt to read any of
those counters leads to a crash like this one:

[42021.807566] BUG: kernel NULL pointer dereference, address: 0000000000000028
[42021.814463] #PF: supervisor read access in kernel mode
[42021.819549] #PF: error_code(0x0000) - not-present page
[42021.824636] PGD 0 P4D 0
[42021.827145] Oops: 0000 [#1] SMP PTI
[42021.830598] CPU: 82 PID: 2843922 Comm: switchto-defaul Kdump: loaded Tainted: G S      W I        XXX
[42021.841697] Hardware name: XXX
[42021.849619] RIP: 0010:hw_stat_device_show+0x1e/0x40 [ib_core]
[42021.855362] Code: 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 49 89 d0 4c 8b 5e 20 48 8b 8f b8 04 00 00 48 81 c7 f0 fa ff ff <48> 8b 41 28 48 29 ce 48 83 c6 d0 48 c1 ee 04 69 d6 ab aa aa aa 48
[42021.873931] RSP: 0018:ffff97fe90f03da0 EFLAGS: 00010287
[42021.879108] RAX: ffff9406988a8c60 RBX: ffff940e1072d438 RCX: 0000000000000000
[42021.886169] RDX: ffff94085f1aa000 RSI: ffff93c6cbbdbcb0 RDI: ffff940c7517aef0
[42021.893230] RBP: ffff97fe90f03e70 R08: ffff94085f1aa000 R09: 0000000000000000
[42021.900294] R10: ffff94085f1aa000 R11: ffffffffc0775680 R12: ffffffff87ca2530
[42021.907355] R13: ffff940651602840 R14: ffff93c6cbbdbcb0 R15: ffff94085f1aa000
[42021.914418] FS:  00007fda1a3b9700(0000) GS:ffff94453fb80000(0000) knlGS:0000000000000000
[42021.922423] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[42021.928130] CR2: 0000000000000028 CR3: 00000042dcfb8003 CR4: 00000000003726f0
[42021.935194] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[42021.942257] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[42021.949324] Call Trace:
[42021.951756]  <TASK>
[42021.953842]  [<ffffffff86c58674>] ? show_regs+0x64/0x70
[42021.959030]  [<ffffffff86c58468>] ? __die+0x78/0xc0
[42021.963874]  [<ffffffff86c9ef75>] ? page_fault_oops+0x2b5/0x3b0
[42021.969749]  [<ffffffff87674b92>] ? exc_page_fault+0x1a2/0x3c0
[42021.975549]  [<ffffffff87801326>] ? asm_exc_page_fault+0x26/0x30
[42021.981517]  [<ffffffffc0775680>] ? __pfx_show_hw_stats+0x10/0x10 [ib_core]
[42021.988482]  [<ffffffffc077564e>] ? hw_stat_device_show+0x1e/0x40 [ib_core]
[42021.995438]  [<ffffffff86ac7f8e>] dev_attr_show+0x1e/0x50
[42022.000803]  [<ffffffff86a3eeb1>] sysfs_kf_seq_show+0x81/0xe0
[42022.006508]  [<ffffffff86a11134>] seq_read_iter+0xf4/0x410
[42022.011954]  [<ffffffff869f4b2e>] vfs_read+0x16e/0x2f0
[42022.017058]  [<ffffffff869f50ee>] ksys_read+0x6e/0xe0
[42022.022073]  [<ffffffff8766f1ca>] do_syscall_64+0x6a/0xa0
[42022.027441]  [<ffffffff8780013b>] entry_SYSCALL_64_after_hwframe+0x78/0xe2

The problem can be reproduced using the following steps:
  ip netns add foo
  ip netns exec foo bash
  cat /sys/class/infiniband/mlx4_0/hw_counters/*

The panic occurs because of casting the device pointer into an
ib_device pointer using container_of() in hw_stat_device_show() is
wrong and leads to a memory corruption.

However the real problem is that hw counters should never been exposed
outside of the non-init net namespace.

Fix this by saving the index of the corresponding attribute group
(it might be 1 or 2 depending on the presence of driver-specific
attributes) and zeroing the pointer to hw_counters group for compat
devices during the initialization.

With this fix applied hw_counters are not available in a non-init
net namespace:
  find /sys/class/infiniband/mlx4_0/ -name hw_counters
    /sys/class/infiniband/mlx4_0/ports/1/hw_counters
    /sys/class/infiniband/mlx4_0/ports/2/hw_counters
    /sys/class/infiniband/mlx4_0/hw_counters

  ip netns add foo
  ip netns exec foo bash
  find /sys/class/infiniband/mlx4_0/ -name hw_counters

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-22089?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-22089?

Apply the vendor's patch.

## Is CVE-2025-22089 being exploited?

There is no known exploitation of CVE-2025-22089 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-2025-22089 and fix it if it is affected.

What it is: CVE-2025-22089 is a high-severity vulnerability in Linux kernel, published on 16 Apr 2025. 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-2025-22089 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-2025-22089/ (Markdown: https://insights.sbomify.com/CVE-2025-22089/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-22089
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-22089
- OSV: https://osv.dev/vulnerability/CVE-2025-22089

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-22089/
Summaries are generated and may contain mistakes; the official description above is the record.