---
id: CVE-2022-49779
title: 'kprobes: Skip clearing aggrprobe''s post_handler in kprobe-on-ftrace case'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case

  In __unregister_kprobe_top(), if the currently unregistered probe has
  post_handler but other c…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 <
    7b0007b28dd970176f2e297c06ae63eea2447127
  - >-
    Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 <
    7d606ae1abcc3eab5408e42444d789dc7def51b8
  - >-
    Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 <
    c49cc2c059b503e962c2f13a806c105f9b757df4
  - >-
    Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 <
    55788ebbe8b365b4375bd56b4ba7db79d393a370
  - >-
    Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 <
    5dd7caf0bdc5d0bae7cf9776b4d739fb09bd5ebb
  - Linux 5.4
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T19:47:31.288437Z'
published: '2025-05-01'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T19:49:45.475Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2022-49779'
references:
  - url: 'https://git.kernel.org/stable/c/7b0007b28dd970176f2e297c06ae63eea2447127'
  - url: 'https://git.kernel.org/stable/c/7d606ae1abcc3eab5408e42444d789dc7def51b8'
  - url: 'https://git.kernel.org/stable/c/c49cc2c059b503e962c2f13a806c105f9b757df4'
  - url: 'https://git.kernel.org/stable/c/55788ebbe8b365b4375bd56b4ba7db79d393a370'
  - url: 'https://git.kernel.org/stable/c/5dd7caf0bdc5d0bae7cf9776b4d739fb09bd5ebb'
tags:
  - cve.org
epss: 0.0022
epssPercentile: 0.12651
ingestedAt: '2026-11-05T22:38:31.590Z'
---

## Overview

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

kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case

In __unregister_kprobe_top(), if the currently unregistered probe has
post_handler but other child probes of the aggrprobe do not have
post_handler, the post_handler of the aggrprobe is cleared. If this is
a ftrace-based probe, there is a problem. In later calls to
disarm_kprobe(), we will use kprobe_ftrace_ops because post_handler is
NULL. But we're armed with kprobe_ipmodify_ops. This triggers a WARN in
__disarm_kprobe_ftrace() and may even cause use-after-free:

  Failed to disarm kprobe-ftrace at kernel_clone+0x0/0x3c0 (error -2)
  WARNING: CPU: 5 PID: 137 at kernel/kprobes.c:1135 __disarm_kprobe_ftrace.isra.21+0xcf/0xe0
  Modules linked in: testKprobe_007(-)
  CPU: 5 PID: 137 Comm: rmmod Not tainted 6.1.0-rc4-dirty #18
  [...]
  Call Trace:
   <TASK>
   __disable_kprobe+0xcd/0xe0
   __unregister_kprobe_top+0x12/0x150
   ? mutex_lock+0xe/0x30
   unregister_kprobes.part.23+0x31/0xa0
   unregister_kprobe+0x32/0x40
   __x64_sys_delete_module+0x15e/0x260
   ? do_user_addr_fault+0x2cd/0x6b0
   do_syscall_64+0x3a/0x90
   entry_SYSCALL_64_after_hwframe+0x63/0xcd
   [...]

For the kprobe-on-ftrace case, we keep the post_handler setting to
identify this aggrprobe armed with kprobe_ipmodify_ops. This way we
can disarm it correctly.

## Affected

- `Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 < 7b0007b28dd970176f2e297c06ae63eea2447127`
- `Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 < 7d606ae1abcc3eab5408e42444d789dc7def51b8`
- `Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 < c49cc2c059b503e962c2f13a806c105f9b757df4`
- `Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 < 55788ebbe8b365b4375bd56b4ba7db79d393a370`
- `Linux >= 0bc11ed5ab60c135aa764a62c02cd5ea68289de4 < 5dd7caf0bdc5d0bae7cf9776b4d739fb09bd5ebb`
- `Linux 5.4`

## Remediation

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