---
id: CVE-2024-43893
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  serial: core: check uartclk for zero to avoid divide by zero

  Calling ioctl TIOCSSERIAL with an invalid baud_base can
  result in uartclk being zero, which will result in…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  serial: core: check uartclk for zero to avoid divide by zero

  Calling ioctl TIOCSSERIAL with an invalid baud_base can
  result in uartclk being zero, which will result in…
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-369
vendor: linux
product: linux_kernel
affected:
  - linux_kernel < 4.19.320
  - 'linux_kernel >= 4.20, < 5.4.282'
  - 'linux_kernel >= 5.5, < 5.10.224'
  - 'linux_kernel >= 5.11, < 5.15.165'
  - 'linux_kernel >= 5.16, < 6.1.105'
  - 'linux_kernel >= 6.2, < 6.6.46'
  - 'linux_kernel >= 6.7, < 6.10.5'
  - linux_kernel = 6.11
patched:
  - linux_kernel 6.10.5
published: '2024-08-26'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T01:18:49.490'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2024-43893'
references:
  - url: 'https://git.kernel.org/stable/c/3bbd90fca824e6fd61fb20f6dd2b0fa5f8b14bba'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/52b138f1021113e593ee6ad258ce08fe90693a9e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/55b2a5d331a6ceb1c4372945fdb77181265ba24f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/68dc02f319b9ee54dc23caba742a5c754d1cccc8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6eabce6608d6f3440f4c03aa3d3ef50a47a3d193'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9196e42a3b8eeff1707e6ef769112b4b6096be49'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e13ba3fe5ee070f8a9dab60029d52b1f61da5051'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e3ad503876283ac3fcca922a1bf243ef9eb0b0e2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-265688.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-355557.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-613116.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00257
epssPercentile: 0.16397
ingestedAt: '2026-10-15T03:30:12.738Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2024-09-10T15:29:15.877067Z'
---

## Overview

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

serial: core: check uartclk for zero to avoid divide by zero

Calling ioctl TIOCSSERIAL with an invalid baud_base can
result in uartclk being zero, which will result in a
divide by zero error in uart_get_divisor(). The check for
uartclk being zero in uart_set_info() needs to be done
before other settings are made as subsequent calls to
ioctl TIOCSSERIAL for the same port would be impacted if
the uartclk check was done where uartclk gets set.

Oops: divide error: 0000  PREEMPT SMP KASAN PTI
RIP: 0010:uart_get_divisor (drivers/tty/serial/serial_core.c:580)
Call Trace:
 <TASK>
serial8250_get_divisor (drivers/tty/serial/8250/8250_port.c:2576
    drivers/tty/serial/8250/8250_port.c:2589)
serial8250_do_set_termios (drivers/tty/serial/8250/8250_port.c:502
    drivers/tty/serial/8250/8250_port.c:2741)
serial8250_set_termios (drivers/tty/serial/8250/8250_port.c:2862)
uart_change_line_settings (./include/linux/spinlock.h:376
    ./include/linux/serial_core.h:608 drivers/tty/serial/serial_core.c:222)
uart_port_startup (drivers/tty/serial/serial_core.c:342)
uart_startup (drivers/tty/serial/serial_core.c:368)
uart_set_info (drivers/tty/serial/serial_core.c:1034)
uart_set_info_user (drivers/tty/serial/serial_core.c:1059)
tty_set_serial (drivers/tty/tty_io.c:2637)
tty_ioctl (drivers/tty/tty_io.c:2647 drivers/tty/tty_io.c:2791)
__x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:907
    fs/ioctl.c:893 fs/ioctl.c:893)
do_syscall_64 (arch/x86/entry/common.c:52
    (discriminator 1) arch/x86/entry/common.c:83 (discriminator 1))
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Rule: add

## Affected

- `linux_kernel < 4.19.320`
- `linux_kernel >= 4.20, < 5.4.282`
- `linux_kernel >= 5.5, < 5.10.224`
- `linux_kernel >= 5.11, < 5.15.165`
- `linux_kernel >= 5.16, < 6.1.105`
- `linux_kernel >= 6.2, < 6.6.46`
- `linux_kernel >= 6.7, < 6.10.5`
- `linux_kernel = 6.11`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.10.5`