---
id: CVE-2022-49309
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drivers: staging: rtl8723bs: Fix deadlock in rtw_surveydone_event_callback()

  There is a deadlock in rtw_surveydone_event_callback(),
  which is shown below:

     (Thread …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drivers: staging: rtl8723bs: Fix deadlock in rtw_surveydone_event_callback()

  There is a deadlock in rtw_surveydone_event_callback(),
  which is shown below:

     (Thread …
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'
cwe:
  - CWE-667
vendor: linux
product: linux_kernel
affected:
  - linux_kernel < 5.15.47
  - 'linux_kernel >= 5.16, < 5.17.15'
  - 'linux_kernel >= 5.18, < 5.18.4'
patched:
  - linux_kernel 5.18.4
published: '2025-02-26'
updated: '2026-08-13'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2022-49309'
references:
  - url: 'https://git.kernel.org/stable/c/2c41f5c341853f84b7bc2f32605d4e2782e8c279'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c84e5c819600ee0628f61b33d145258ae0f3d7a7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cc7ad0d77b51c872d629bcd98aea463a3c4109e7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ce129d3efd181da5fd56f4360cc8827122afa67e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f89f6c3ebf69623b8ea48200bd690e9e210335a1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00199
epssPercentile: 0.08647
ingestedAt: '2026-08-13T00:57:23.048Z'
---

## Overview

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

drivers: staging: rtl8723bs: Fix deadlock in rtw_surveydone_event_callback()

There is a deadlock in rtw_surveydone_event_callback(),
which is shown below:

   (Thread 1)                  |      (Thread 2)
                               | _set_timer()
rtw_surveydone_event_callback()|  mod_timer()
 spin_lock_bh() //(1)          |  (wait a time)
 ...                           | rtw_scan_timeout_handler()
 del_timer_sync()              |  spin_lock_bh() //(2)
 (wait timer to stop)          |  ...

We hold pmlmepriv->lock in position (1) of thread 1 and use
del_timer_sync() to wait timer to stop, but timer handler
also need pmlmepriv->lock in position (2) of thread 2.
As a result, rtw_surveydone_event_callback() will block forever.

This patch extracts del_timer_sync() from the protection of
spin_lock_bh(), which could let timer handler to obtain
the needed lock. What`s more, we change spin_lock_bh() in
rtw_scan_timeout_handler() to spin_lock_irq(). Otherwise,
spin_lock_bh() will also cause deadlock() in timer handler.

## Affected

- `linux_kernel < 5.15.47`
- `linux_kernel >= 5.16, < 5.17.15`
- `linux_kernel >= 5.18, < 5.18.4`

## Remediation

Upgrade past the affected range:

- `linux_kernel 5.18.4`