CVE-2026-31486 (GCVE-0-2026-31486)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-06-19 11:57
VLAI?
Title
hwmon: (pmbus/core) Protect regulator operations with mutex
Summary
In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/core) Protect regulator operations with mutex The regulator operations pmbus_regulator_get_voltage(), pmbus_regulator_set_voltage(), and pmbus_regulator_list_voltage() access PMBus registers and shared data but were not protected by the update_lock mutex. This could lead to race conditions. However, adding mutex protection directly to these functions causes a deadlock because pmbus_regulator_notify() (which calls regulator_notifier_call_chain()) is often called with the mutex already held (e.g., from pmbus_fault_handler()). If a regulator callback then calls one of the now-protected voltage functions, it will attempt to acquire the same mutex. Rework pmbus_regulator_notify() to utilize a worker function to send notifications outside of the mutex protection. Events are stored as atomics in a per-page bitmask and processed by the worker. Initialize the worker and its associated data during regulator registration, and ensure it is cancelled on device removal using devm_add_action_or_reset(). While at it, remove the unnecessary include of linux/of.h.
Assigner
Impacted products
Vendor Product Version
Linux Linux Affected: ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 , < b26849cffaa7c43355b82e9bef3725e786973a1a (git)
Affected: ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 , < acf04e2863132f6d9222f71f3a76fb9782cbe061 (git)
Affected: ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 , < 4e9d723d9f198b86f6882a84c501ba1f39e8d055 (git)
Affected: ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 , < 2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07 (git)
Affected: ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7 , < 754bd2b4a084b90b5e7b630e1f423061a9b9b761 (git)
Create a notification for this product.
    Linux Linux Affected: 3.19
Unaffected: 0 , < 3.19 (semver)
Unaffected: 6.6.143 , ≤ 6.6.* (semver)
Unaffected: 6.12.92 , ≤ 6.12.* (semver)
Unaffected: 6.18.21 , ≤ 6.18.* (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/hwmon/pmbus/pmbus_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "b26849cffaa7c43355b82e9bef3725e786973a1a",
              "status": "affected",
              "version": "ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7",
              "versionType": "git"
            },
            {
              "lessThan": "acf04e2863132f6d9222f71f3a76fb9782cbe061",
              "status": "affected",
              "version": "ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7",
              "versionType": "git"
            },
            {
              "lessThan": "4e9d723d9f198b86f6882a84c501ba1f39e8d055",
              "status": "affected",
              "version": "ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7",
              "versionType": "git"
            },
            {
              "lessThan": "2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07",
              "status": "affected",
              "version": "ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7",
              "versionType": "git"
            },
            {
              "lessThan": "754bd2b4a084b90b5e7b630e1f423061a9b9b761",
              "status": "affected",
              "version": "ddbb4db4ced1ba784fcd3500179a7291b6c5d7b7",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/hwmon/pmbus/pmbus_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.19"
            },
            {
              "lessThan": "3.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.143",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.92",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.21",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.143",
                  "versionStartIncluding": "3.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.92",
                  "versionStartIncluding": "3.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.21",
                  "versionStartIncluding": "3.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.11",
                  "versionStartIncluding": "3.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "3.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus/core) Protect regulator operations with mutex\n\nThe regulator operations pmbus_regulator_get_voltage(),\npmbus_regulator_set_voltage(), and pmbus_regulator_list_voltage()\naccess PMBus registers and shared data but were not protected by\nthe update_lock mutex. This could lead to race conditions.\n\nHowever, adding mutex protection directly to these functions causes\na deadlock because pmbus_regulator_notify() (which calls\nregulator_notifier_call_chain()) is often called with the mutex\nalready held (e.g., from pmbus_fault_handler()). If a regulator\ncallback then calls one of the now-protected voltage functions,\nit will attempt to acquire the same mutex.\n\nRework pmbus_regulator_notify() to utilize a worker function to\nsend notifications outside of the mutex protection. Events are\nstored as atomics in a per-page bitmask and processed by the worker.\n\nInitialize the worker and its associated data during regulator\nregistration, and ensure it is cancelled on device removal using\ndevm_add_action_or_reset().\n\nWhile at it, remove the unnecessary include of linux/of.h."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-19T11:57:45.891Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/b26849cffaa7c43355b82e9bef3725e786973a1a"
        },
        {
          "url": "https://git.kernel.org/stable/c/acf04e2863132f6d9222f71f3a76fb9782cbe061"
        },
        {
          "url": "https://git.kernel.org/stable/c/4e9d723d9f198b86f6882a84c501ba1f39e8d055"
        },
        {
          "url": "https://git.kernel.org/stable/c/2c77ae315f3ce9d2c8e1609be74c9358c1fe4e07"
        },
        {
          "url": "https://git.kernel.org/stable/c/754bd2b4a084b90b5e7b630e1f423061a9b9b761"
        }
      ],
      "title": "hwmon: (pmbus/core) Protect regulator operations with mutex",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31486",
    "datePublished": "2026-04-22T13:54:11.594Z",
    "dateReserved": "2026-03-09T15:48:24.101Z",
    "dateUpdated": "2026-06-19T11:57:45.891Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…