---
id: CVE-2026-64192
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized

  When CONFIG_BPF_LSM=y is set, BPF inode storage maps
  (BPF_MAP_TYPE_INODE_STORAGE) are compi…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized

  When CONFIG_BPF_LSM=y is set, BPF inode storage maps
  (BPF_MAP_TYPE_INODE_STORAGE) are compi…
severity: medium
published: '2026-07-20'
updated: '2026-08-03'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64192'
references:
  - url: 'https://git.kernel.org/stable/c/267fdd9b6530c399dfd996e1a0a7628b45baf9f0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5337eebdf8c5d4810b1913047f078d2815d5645f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c76b8abce575e0c6e4096957220b4515ed847d89'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/de984ea883405420fdc416ae8964b752df586970'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64192.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-64192'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2502884'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-64192'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64192'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026072052-CVE-2026-64192-8cd7@gregkh/T
tags:
  - nvd
  - csaf
  - vex
  - red-hat
epss: 0.00118
epssPercentile: 0.01978
ingestedAt: '2026-08-03T10:24:20.595Z'
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 8
  - enterprise_linux 9
cvss: 6.4
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H'
cvssSource: vendor
cwe:
  - CWE-476
---

## Overview

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

bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized

When CONFIG_BPF_LSM=y is set, BPF inode storage maps
(BPF_MAP_TYPE_INODE_STORAGE) are compiled into the kernel. However,
if the BPF LSM is not explicitly enabled at boot time (e.g. omitted
from the "lsm=" boot parameter), lsm_prepare() is never executed for
the BPF LSM.

Consequently, the BPF inode security blob offset
(bpf_lsm_blob_sizes.lbs_inode) is never initialized and remains at
its default compiled size of 8 bytes instead of being updated to a
valid offset past the reserved struct rcu_head (typically 16 bytes
or more).

When a privileged user creates and updates a BPF_MAP_TYPE_INODE_STORAGE
map, bpf_inode() evaluates inode->i_security + 8. This erroneously
aliases the struct rcu_head.func callback pointer at the beginning
of the inode->i_security blob. During subsequent map element cleanup
or inode destruction, writing NULL to owner_storage clears the queued
RCU callback pointer. When rcu_do_batch() later executes the queued
callback, it attempts an instruction fetch at address 0x0, triggering
an immediate kernel panic.

Fix this by introducing a global bpf_lsm_initialized boolean flag
marked with __ro_after_init. Set this flag to true inside bpf_lsm_init()
when the LSM framework successfully registers the BPF LSM. Gate map
allocation in inode_storage_map_alloc() on this flag, returning
-EOPNOTSUPP if the BPF LSM is in turn uninitialized.

This fail-fast approach prevents userspace from allocating inode
storage maps when the supporting BPF LSM infrastructure is absent,
avoiding zombie map states.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64192.json)