---
id: CVE-2026-89801
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drm/nouveau/uvmm: fix premature region free on failed OP_UNMAP_SPARSE

  In nouveau_uvmm_bind_job_submit()'s OP_UNMAP_SPARSE arm, op->reg is set
  from nouveau_uvma_region_…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drm/nouveau/uvmm: fix premature region free on failed OP_UNMAP_SPARSE

  In nouveau_uvmm_bind_job_submit()'s OP_UNMAP_SPARSE arm, op->reg is set
  from nouveau_uvma_region_…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= b88baab828713ce0b49b185444b2ee83bed373a8 <
    ba42d8a1c2c7629c61914df11a7d63ac77449ffb
  - >-
    Linux >= b88baab828713ce0b49b185444b2ee83bed373a8 <
    88114e3a96582882e63b2f73aa7a5a9cf0d5073c
  - >-
    Linux >= b88baab828713ce0b49b185444b2ee83bed373a8 <
    24c25b182d17d1bdfde0088c96bdf6f93e8f46bc
  - >-
    Linux >= b88baab828713ce0b49b185444b2ee83bed373a8 <
    4083d24c2636fde7b18076115af52820d203bc57
  - >-
    Linux >= b88baab828713ce0b49b185444b2ee83bed373a8 <
    ccf930812f23b8259ef64fd3394d53b093e4651a
  - Linux 6.6
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T15:18:09.867'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89801'
references:
  - url: 'https://git.kernel.org/stable/c/24c25b182d17d1bdfde0088c96bdf6f93e8f46bc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4083d24c2636fde7b18076115af52820d203bc57'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/88114e3a96582882e63b2f73aa7a5a9cf0d5073c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ba42d8a1c2c7629c61914df11a7d63ac77449ffb'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ccf930812f23b8259ef64fd3394d53b093e4651a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-16T10:53:54.008Z'
epss: 0.0017
epssPercentile: 0.05564
---

## Overview

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

drm/nouveau/uvmm: fix premature region free on failed OP_UNMAP_SPARSE

In nouveau_uvmm_bind_job_submit()'s OP_UNMAP_SPARSE arm, op->reg is set
from nouveau_uvma_region_find(), which only looks the region up and takes
no reference; a region's sole reference is its membership in
uvmm->region_mt. Two failure paths leave op->reg set: the -ENOENT check
when the region is busy, and the drm_gpuvm_sm_unmap_ops_create() failure.
The sibling nouveau_uvmm_sm_unmap_prepare() failure just below clears
op->reg; these two do not.

unwind_continue steps back one op, so the failing op is skipped by the
unwind loop and its op->reg stays set. nouveau_uvmm_bind_job_cleanup()
then enters its if (op->reg) branch and calls nouveau_uvma_region_remove()
and nouveau_uvma_region_put() on it, dropping the tree's sole reference
and freeing a region this job never created. The comment above the
cleanup loop documents the broken invariant: op->reg must be NULL on
submit failure.

This frees a live region on an unrelated failure, reachable single-job
when drm_gpuvm_sm_unmap_ops_create() returns -ENOMEM; if another job owns
the same region, its cleanup then removes and puts the freed region, a
use-after-free. Clear op->reg on both failure paths.

## Remediation

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