# CVE-2025-22091: RDMA/mlx5: Fix page_size variable overflow

> An integer overflow in the Linux kernel RDMA driver causes a kernel warning and potential denial of service when registering large contiguous memory regions.

- **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:** 16 Apr 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-22091, DEBIAN-CVE-2025-22091, GHSA-rxxj-rv84-8c37, UBUNTU-CVE-2025-22091

## What is CVE-2025-22091?

CVE-2025-22091 is a medium-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/mlx5: Fix page_size variable overflow

Change all variables storing mlx5_umem_mkc_find_best_pgsz() result to
unsigned long to support values larger than 31 and avoid overflow.

For example: If we try to register 4GB of memory that is contiguous in
physical memory, the driver will optimize the page_size and try to use
an mkey with 4GB entity size. The 'unsigned int' page_size variable will
overflow to '0' and we'll hit the WARN_ON() in alloc_cacheable_mr().

WARNING: CPU: 2 PID: 1203 at drivers/infiniband/hw/mlx5/mr.c:1124 alloc_cacheable_mr+0x22/0x580 [mlx5_ib]
Modules linked in: mlx5_ib mlx5_core bonding ip6_gre ip6_tunnel tunnel6 ip_gre gre rdma_rxe rdma_ucm ib_uverbs ib_ipoib ib_umad rpcrdma ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm fuse ib_core [last unloaded: mlx5_core]
CPU: 2 UID: 70878 PID: 1203 Comm: rdma_resource_l Tainted: G        W          6.14.0-rc4-dirty #43
Tainted: [W]=WARN
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:alloc_cacheable_mr+0x22/0x580 [mlx5_ib]
Code: 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 41 52 53 48 83 ec 30 f6 46 28 04 4c 8b 77 08 75 21 <0f> 0b 49 c7 c2 ea ff ff ff 48 8d 65 d0 4c 89 d0 5b 41 5a 41 5c 41
RSP: 0018:ffffc900006ffac8 EFLAGS: 00010246
RAX: 0000000004c0d0d0 RBX: ffff888217a22000 RCX: 0000000000100001
RDX: 00007fb7ac480000 RSI: ffff8882037b1240 RDI: ffff8882046f0600
RBP: ffffc900006ffb28 R08: 0000000000000001 R09: 0000000000000000
R10: 00000000000007e0 R11: ffffea0008011d40 R12: ffff8882037b1240
R13: ffff8882046f0600 R14: ffff888217a22000 R15: ffffc900006ffe00
FS:  00007fb7ed013340(0000) GS:ffff88885fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb7ed1d8000 CR3: 00000001fd8f6006 CR4: 0000000000772eb0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 ? __warn+0x81/0x130
 ? alloc_cacheable_mr+0x22/0x580 [mlx5_ib]
 ? report_bug+0xfc/0x1e0
 ? handle_bug+0x55/0x90
 ? exc_invalid_op+0x17/0x70
 ? asm_exc_invalid_op+0x1a/0x20
 ? alloc_cacheable_mr+0x22/0x580 [mlx5_ib]
 create_real_mr+0x54/0x150 [mlx5_ib]
 ib_uverbs_reg_mr+0x17f/0x2a0 [ib_uverbs]
 ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0xca/0x140 [ib_uverbs]
 ib_uverbs_run_method+0x6d0/0x780 [ib_uverbs]
 ? __pfx_ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0x10/0x10 [ib_uverbs]
 ib_uverbs_cmd_verbs+0x19b/0x360 [ib_uverbs]
 ? walk_system_ram_range+0x79/0xd0
 ? ___pte_offset_map+0x1b/0x110
 ? __pte_offset_map_lock+0x80/0x100
 ib_uverbs_ioctl+0xac/0x110 [ib_uverbs]
 __x64_sys_ioctl+0x94/0xb0
 do_syscall_64+0x50/0x110
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fb7ecf0737b
Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 7d 2a 0f 00 f7 d8 64 89 01 48
RSP: 002b:00007ffdbe03ecc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffdbe03edb8 RCX: 00007fb7ecf0737b
RDX: 00007ffdbe03eda0 RSI: 00000000c0181b01 RDI: 0000000000000003
RBP: 00007ffdbe03ed80 R08: 00007fb7ecc84010 R09: 00007ffdbe03eed4
R10: 0000000000000009 R11: 0000000000000246 R12: 00007ffdbe03eed4
R13: 000000000000000c R14: 000000000000000c R15: 00007fb7ecc84150
 </TASK>

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2025-22091?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-22091?

Apply the vendor's patch.

## Is CVE-2025-22091 being exploited?

There is no known exploitation of CVE-2025-22091 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-2025-22091 and fix it if it is affected.

What it is: CVE-2025-22091 is a medium-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-2025-22091 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-2025-22091/ (Markdown: https://insights.sbomify.com/CVE-2025-22091/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-22091
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-22091
- OSV: https://osv.dev/vulnerability/CVE-2025-22091

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-22091/
Summaries are generated and may contain mistakes; the official description above is the record.