CVE-2026-74605

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: eventfs: Use children field for rcu head and add memory barriers When an eventfs inode is freed, it sets ei->is_freed and then uses its ei->list to add it to the srcu link list as the list field is a union with the rcu list head. As the ei->list is used to iterate over an SRCU protected list without taking the eventfs_mutex, there's nothing stopping the iteration over that list to see the ei->rcu instead of the ei->list and it will read a corrupt target. To fix this, change the union of the rcu list head with the children list. On freeing the eventfs inode, set the is_free and execute a smp_wmb() before adding the eventfs inode to the SRCU list. On iteration of the ei->children list, at the start, execute a smp_rmb() and then read the is_freed of the ei to see if the children list is still valid. If is_freed is set, then the ei_child read is not valid and the loop should exit immediately.

Severity

HIGH

CVSS score

7.8 (v3.1)

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-08-22 16:16:32.977000

Last modified

2026-10-21 13:19:47.930000

View original CVE JSON

{
  "id": "CVE-2026-74605",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-22T16:16:32.977",
  "lastModified": "2026-10-21T13:19:47.930",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\neventfs: Use children field for rcu head and add memory barriers\n\nWhen an eventfs inode is freed, it sets ei->is_freed and then uses its\nei->list to add it to the srcu link list as the list field is a union with\nthe rcu list head. As the ei->list is used to iterate over an SRCU\nprotected list without taking the eventfs_mutex, there's nothing stopping\nthe iteration over that list to see the ei->rcu instead of the ei->list\nand it will read a corrupt target.\n\nTo fix this, change the union of the rcu list head with the children list.\nOn freeing the eventfs inode, set the is_free and execute a smp_wmb()\nbefore adding the eventfs inode to the SRCU list.\n\nOn iteration of the ei->children list, at the start, execute a smp_rmb()\nand then read the is_freed of the ei to see if the children list is still\nvalid. If is_freed is set, then the ei_child read is not valid and the\nloop should exit immediately."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\neventfs: Usar el campo children para la cabecera rcu y añadir barreras de memoria\n\nCuando un inodo eventfs es liberado, establece ei -> is_freed y luego usa su ei -> list para añadirlo a la lista de enlaces srcu ya que el campo list es una unión con la cabecera de la lista rcu. Como el ei -> list se usa para iterar sobre una lista protegida por SRCU sin tomar el eventfs_mutex, no hay nada que impida que la iteración sobre esa lista vea el ei -> rcu en lugar del ei -> list y leerá un objetivo corrupto.\n\nPara solucionar esto, cambiar la unión de la cabecera de la lista rcu con la lista children. Al liberar el inodo eventfs, establecer el is_free y ejecutar un smp_wmb() antes de añadir el inodo eventfs a la lista SRCU.\n\nEn la iteración de la lista ei -> children, al inicio, ejecutar un smp_rmb() y luego leer el is_freed del ei para ver si la lista children sigue siendo válida. Si is_freed está establecido, entonces la lectura de ei_child no es válida y el bucle debería salir inmediatamente."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/tracefs/event_inode.c",
            "fs/tracefs/internal.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "f3f41f444b321ec393edbc251e024fd62658ce55",
              "lessThan": "25d27d5fa8645ab61018c3efec5c69f49280ca7d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "704f960dbee2f1634f4b4e16f208cb16eaf41c1e",
              "lessThan": "1b95382da85cff3bf0f922ff0275f186abdadfce",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "704f960dbee2f1634f4b4e16f208cb16eaf41c1e",
              "lessThan": "2b80707b9e27671e10840d17c6f8f774c4ad9847",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "704f960dbee2f1634f4b4e16f208cb16eaf41c1e",
              "lessThan": "004f7232e49730448f91665e76bdd7dff8e0c638",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "704f960dbee2f1634f4b4e16f208cb16eaf41c1e",
              "lessThan": "f0ece16ffca7384787b692431961ce202907acf5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "305c4e4d80aca2c2d9cf2ebdea56e2eca6d3a6aa",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6.6.18",
              "lessThan": "6.6.160",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.7.6",
              "lessThan": "6.8",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/tracefs/event_inode.c",
            "fs/tracefs/internal.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.8",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.8",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.57",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.9",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/004f7232e49730448f91665e76bdd7dff8e0c638",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1b95382da85cff3bf0f922ff0275f186abdadfce",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/25d27d5fa8645ab61018c3efec5c69f49280ca7d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2b80707b9e27671e10840d17c6f8f774c4ad9847",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f0ece16ffca7384787b692431961ce202907acf5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}