---
id: CVE-2026-74547
title: 'hwmon: (adt7470) Fix busy-loop and I2C flooding in update thread'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  hwmon: (adt7470) Fix busy-loop and I2C flooding in update thread

  When userspace configures 'auto_update_interval' to 0 via sysfs, the
  background kthread executes sched…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    2c4c4d7cadd10b50b5489183bbbb9eb95f6f8344
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    4dc1518f9cc57c6db99514cafeb02dd7117d5bda
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    1325975a2eab265510e6036d8bf0c0068373d332
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    1a42bd72a66205e439db1d1142442b62d393408a
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    38e6b5ce5794ff09442231cc171c2be5e900bab3
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    82d65f7ef11edcea0228745440b8b4b1f222c34c
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    5ea299c3aa42a827f6a863eeead6de3525bbb17a
  - >-
    Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d <
    cb0b7f9c43b0abbd422a7e4c2c85e91db429207c
  - Linux 2.6.29
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T16:59:34.531813Z'
published: '2026-08-15'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T17:05:48.230Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74547'
references:
  - url: 'https://git.kernel.org/stable/c/2c4c4d7cadd10b50b5489183bbbb9eb95f6f8344'
  - url: 'https://git.kernel.org/stable/c/4dc1518f9cc57c6db99514cafeb02dd7117d5bda'
  - url: 'https://git.kernel.org/stable/c/1325975a2eab265510e6036d8bf0c0068373d332'
  - url: 'https://git.kernel.org/stable/c/1a42bd72a66205e439db1d1142442b62d393408a'
  - url: 'https://git.kernel.org/stable/c/38e6b5ce5794ff09442231cc171c2be5e900bab3'
  - url: 'https://git.kernel.org/stable/c/82d65f7ef11edcea0228745440b8b4b1f222c34c'
  - url: 'https://git.kernel.org/stable/c/5ea299c3aa42a827f6a863eeead6de3525bbb17a'
  - url: 'https://git.kernel.org/stable/c/cb0b7f9c43b0abbd422a7e4c2c85e91db429207c'
tags:
  - cve.org
epss: 0.00177
epssPercentile: 0.07334
ingestedAt: '2026-11-06T18:00:12.549Z'
---

## Overview

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

hwmon: (adt7470) Fix busy-loop and I2C flooding in update thread

When userspace configures 'auto_update_interval' to 0 via sysfs, the
background kthread executes schedule_timeout_interruptible(0), which
returns immediately.

If 'num_temp_sensors' is concurrently or previously set to 0, the
msleep_interruptible() delay inside adt7470_read_temperatures() also
becomes 0. This combination forces the background thread into a tight,
unbounded busy-loop, hogging the CPU and flooding the I2C bus with a
continuous stream of transactions.

Fix this vulnerability by raising the lower limit of the clamp_val in
auto_update_interval_store() from 0 to 500 milliseconds. This guarantees
a reasonable minimum sleep window between sensor updates, protecting the
system from intentional or accidental I2C bus denial of service.

## Affected

- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < 2c4c4d7cadd10b50b5489183bbbb9eb95f6f8344`
- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < 4dc1518f9cc57c6db99514cafeb02dd7117d5bda`
- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < 1325975a2eab265510e6036d8bf0c0068373d332`
- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < 1a42bd72a66205e439db1d1142442b62d393408a`
- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < 38e6b5ce5794ff09442231cc171c2be5e900bab3`
- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < 82d65f7ef11edcea0228745440b8b4b1f222c34c`
- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < 5ea299c3aa42a827f6a863eeead6de3525bbb17a`
- `Linux >= 89fac11cb3e7c5860c425dba14845c09ccede39d < cb0b7f9c43b0abbd422a7e4c2c85e91db429207c`
- `Linux 2.6.29`

## Remediation

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