---
id: CVE-2026-46040
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  inotify: fix watch count leak when fsnotify_add_inode_mark_locked() fails

  When fsnotify_add_inode_mark_locked() fails in inotify_new_watch(),
  the error path calls inot…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  inotify: fix watch count leak when fsnotify_add_inode_mark_locked() fails

  When fsnotify_add_inode_mark_locked() fails in inotify_new_watch(),
  the error path calls inot…
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'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 4.11, < 5.10.258'
  - 'linux_kernel >= 5.11, < 5.15.209'
  - 'linux_kernel >= 5.16, < 6.1.175'
  - 'linux_kernel >= 6.2, < 6.6.140'
  - 'linux_kernel >= 6.7, < 6.12.86'
  - 'linux_kernel >= 6.13, < 6.18.27'
  - 'linux_kernel >= 6.19, < 7.0.4'
patched:
  - linux_kernel 7.0.4
published: '2026-05-27'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T09:18:07.063'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-46040'
references:
  - url: 'https://git.kernel.org/stable/c/10edf7e0ffdc7faa18e2244b17722c1b882b8273'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3ab58cf42c46bf2366d2f55ae5c59299d5e178b7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3ad9ccea1b25435f6179b57aa891960beb7ce8f9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6a320935fa4293e9e599ec9f85dc9eb3be7029f8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/73ddc8518a32baff6bc17afda4ee1ebae5b4ed12'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8bcc1cd237ab5ccfdd102869fa031c541943cf40'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9e48844f708eb48bae4e79cb21edc097c966306d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/fdaa42ca370d056428e5e171247c8fdce8dff36a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00166
epssPercentile: 0.05207
ingestedAt: '2026-09-08T13:33:24.347Z'
---

## Overview

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

inotify: fix watch count leak when fsnotify_add_inode_mark_locked() fails

When fsnotify_add_inode_mark_locked() fails in inotify_new_watch(),
the error path calls inotify_remove_from_idr() but does not call
dec_inotify_watches() to undo the preceding inc_inotify_watches().
This leaks a watch count, and repeated failures can exhaust the
max_user_watches limit with -ENOSPC even when no watches are active.

Prior to commit 1cce1eea0aff ("inotify: Convert to using per-namespace
limits"), the watch count was incremented after fsnotify_add_mark_locked()
succeeded, so this path was not affected. The conversion moved
inc_inotify_watches() before the mark insertion without adding the
corresponding rollback.

Add the missing dec_inotify_watches() call in the error path.

## Affected

- `linux_kernel >= 4.11, < 5.10.258`
- `linux_kernel >= 5.11, < 5.15.209`
- `linux_kernel >= 5.16, < 6.1.175`
- `linux_kernel >= 6.2, < 6.6.140`
- `linux_kernel >= 6.7, < 6.12.86`
- `linux_kernel >= 6.13, < 6.18.27`
- `linux_kernel >= 6.19, < 7.0.4`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.4`