---
id: CVE-2026-89449
title: >-
  iommu: Fix dev_iommu memory leak when device_add fails in
  iommu_mock_device_add
summary: >-
  In the Linux kernel, the following vulnerability has been resolved:


  iommu: Fix dev_iommu memory leak when device_add fails in
  iommu_mock_device_add


  iommu_mock_device_add() first calls iommu_fwspec_init(), which on

  success allocates bot…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe:
  - CWE-772
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 2a918911ed3d0841923525ed0fe707762ee78844 <
    f80f3acb69164800051ecdee871b6b006cbc2e66
  - >-
    Linux >= 2a918911ed3d0841923525ed0fe707762ee78844 <
    eaf44262af24810d16800b988c92dfce90f73370
  - >-
    Linux >= 2a918911ed3d0841923525ed0fe707762ee78844 <
    b7b0b3851474883d4aba6ed72da87141204b23e5
  - Linux 1daf67217b0d0bf88ef7208d7fbeefe2378c6590
  - Linux >= 6.17.3 < 6.18
  - Linux 6.18
published: '2026-09-11'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T08:46:58.738Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-89449'
references:
  - url: 'https://git.kernel.org/stable/c/f80f3acb69164800051ecdee871b6b006cbc2e66'
  - url: 'https://git.kernel.org/stable/c/eaf44262af24810d16800b988c92dfce90f73370'
  - url: 'https://git.kernel.org/stable/c/b7b0b3851474883d4aba6ed72da87141204b23e5'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89449.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89449'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532262'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89449'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89449'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89449.mbox
tags:
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00206
epssPercentile: 0.10631
ingestedAt: '2026-09-14T00:35:28.531Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

iommu: Fix dev_iommu memory leak when device_add fails in iommu_mock_device_add

iommu_mock_device_add() first calls iommu_fwspec_init(), which on
success allocates both dev->iommu (via dev_iommu_get()) and
dev->iommu->fwspec. If the subsequent device_add(dev) call fails,
the error path only calls iommu_fwspec_free(dev), which frees
fwspec but leaves dev->iommu still allocated.

This triggers the following kmemleak report when fuzzing with Syzkaller:

BUG: memory leak
unreferenced object 0xffff888011e0a200 (size 192):
  comm "syz.1.1695", pid 24885, jiffies 4295222527
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 ad 4e ad de  .............N..
    ff ff ff ff 00 00 00 00 ff ff ff ff ff ff ff ff  ................
  backtrace (crc 25df5bb3):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4575 [inline]
    slab_alloc_node mm/slub.c:4899 [inline]
    __kmalloc_cache_noprof+0x47a/0x710 mm/slub.c:5415
    kmalloc_noprof include/linux/slab.h:950 [inline]
    kzalloc_noprof include/linux/slab.h:1188 [inline]
    dev_iommu_get+0x10c/0x1a0 drivers/iommu/iommu.c:408
    iommu_fwspec_init+0x288/0x4d0 drivers/iommu/iommu.c:3087
    iommu_mock_device_add+0x46/0xb0 drivers/iommu/iommu.c:385
    mock_dev_create drivers/iommu/iommufd/selftest.c:1025 [inline]
    iommufd_test_mock_domain drivers/iommu/iommufd/selftest.c:1066 [inline]
    iommufd_test+0x2f8a/0x6190 drivers/iommu/iommufd/selftest.c:2072
    iommufd_fops_ioctl+0x367/0x540 drivers/iommu/iommufd/main.c:533
    vfs_ioctl fs/ioctl.c:51 [inline]
    __do_sys_ioctl fs/ioctl.c:597 [inline]
    __se_sys_ioctl fs/ioctl.c:583 [inline]
    __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fix this by calling dev_iommu_free(dev) instead of iommu_fwspec_free(dev)
in the device_add() failure path. dev_iommu_free() frees both fwspec
and the outer dev_iommu struct and clears dev->iommu.

## Affected

- `Linux >= 2a918911ed3d0841923525ed0fe707762ee78844 < f80f3acb69164800051ecdee871b6b006cbc2e66`
- `Linux >= 2a918911ed3d0841923525ed0fe707762ee78844 < eaf44262af24810d16800b988c92dfce90f73370`
- `Linux >= 2a918911ed3d0841923525ed0fe707762ee78844 < b7b0b3851474883d4aba6ed72da87141204b23e5`
- `Linux 1daf67217b0d0bf88ef7208d7fbeefe2378c6590`
- `Linux >= 6.17.3 < 6.18`
- `Linux 6.18`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89449.json)