---
id: CVE-2026-93173
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  bpf,lsm: Drop bpf_prog_free from sleepable_lsm_hooks

  __bpf_prog_put_rcu() is the call_rcu() callback for non-sleepable programs.
  security_bpf_prog_free() called from t…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  bpf,lsm: Drop bpf_prog_free from sleepable_lsm_hooks

  __bpf_prog_put_rcu() is the call_rcu() callback for non-sleepable programs.
  security_bpf_prog_free() called from t…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1b67772e4e3f16cd647b229cae95fc06d120be08 <
    2135f661fae7160a7fc603cab43cbc7999e8bfce
  - >-
    Linux >= 1b67772e4e3f16cd647b229cae95fc06d120be08 <
    d5f2f741a900123fbcb7c7c0a002b81306fbe242
  - >-
    Linux >= 1b67772e4e3f16cd647b229cae95fc06d120be08 <
    915c2d9d69fc6c5f9f41d12bf4a9c51293aaee62
  - >-
    Linux >= 1b67772e4e3f16cd647b229cae95fc06d120be08 <
    2ce3f548cfc6a1fe4c53479cf8a21931cdfd51d8
  - Linux 6.9
published: '2026-09-17'
updated: '2026-09-17'
sourceUpdated: '2026-09-17T17:18:13.057'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-93173'
references:
  - url: 'https://git.kernel.org/stable/c/2135f661fae7160a7fc603cab43cbc7999e8bfce'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/2ce3f548cfc6a1fe4c53479cf8a21931cdfd51d8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/915c2d9d69fc6c5f9f41d12bf4a9c51293aaee62'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d5f2f741a900123fbcb7c7c0a002b81306fbe242'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-17T16:21:47.730Z'
epss: 0.00209
epssPercentile: 0.09958
---

## Overview

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

bpf,lsm: Drop bpf_prog_free from sleepable_lsm_hooks

__bpf_prog_put_rcu() is the call_rcu() callback for non-sleepable programs.
security_bpf_prog_free() called from there fires bpf_prog_free in softirq;
if a sleepable LSM prog is attached to that hook, might_fault() BUGs:

  BUG: sleeping function called from invalid context
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5038
  preempt_count: 101, expected: 0
  Call Trace:
   <IRQ>
   __bpf_prog_enter_sleepable+0x1cd/0x320 kernel/bpf/trampoline.c:1255
   bpf_trampoline_6442549705+0x53/0xd7
   security_bpf_prog_free+0xde/0x130 security/security.c:5465
   __bpf_prog_put_rcu+0xab/0xd0 kernel/bpf/syscall.c:2365
   rcu_do_batch kernel/rcu/tree.c:2617 [inline]
   handle_softirqs+0x236/0x800 kernel/softirq.c:622
   </IRQ>

The call_rcu/call_rcu_tasks_trace split reflects the freed program's
sleepability, not that of any attached observer.

security_bpf_prog_free() also frees prog->aux->security, which has to stay
after the grace period, so drop bpf_prog_free from sleepable_lsm_hooks
rather than move the call. Non-sleepable observers still run there.

## Remediation

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