CVE-2026-93084

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scmi: Drop handle on protocol bind failures The SCMI bus notifier acquires an SCMI handle when the driver core emits BUS_NOTIFY_BIND_DRIVER, before invoking the protocol driver probe callback. The protocol probe path only checks whether sdev->handle is set. If device_link_add() fails after the handle has been acquired, the protocol device can still bind with a valid handle but without the dependency link to the SCMI parent. A concurrent parent unbind can then miss the child and tear down the SCMI instance while the child still holds a handle into it. If the protocol driver probe later fails, for example with -EPROBE_DEFER, the driver core emits BUS_NOTIFY_DRIVER_NOT_BOUND rather than BUS_NOTIFY_UNBOUND_DRIVER. The SCMI notifier only released the handle on BUS_NOTIFY_UNBOUND_DRIVER, so each failed protocol-device bind leaked the SCMI instance users refcount and left sdev->handle set after the failed probe. Make the link helper report failure and drop the acquired handle if the link cannot be created. Also handle BUS_NOTIFY_DRIVER_NOT_BOUND in the same cleanup path used for unbind so failed probes balance the earlier BUS_NOTIFY_BIND_DRIVER acquisition.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

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

Published

2026-09-17 17:18:02.460000

Last modified

2026-10-30 13:20:56.447000

View original CVE JSON

{
  "id": "CVE-2026-93084",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:18:02.460",
  "lastModified": "2026-10-30T13:20:56.447",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfirmware: arm_scmi: Drop handle on protocol bind failures\n\nThe SCMI bus notifier acquires an SCMI handle when the driver core emits\nBUS_NOTIFY_BIND_DRIVER, before invoking the protocol driver probe\ncallback. The protocol probe path only checks whether sdev->handle is\nset.\n\nIf device_link_add() fails after the handle has been acquired, the\nprotocol device can still bind with a valid handle but without the\ndependency link to the SCMI parent. A concurrent parent unbind can then\nmiss the child and tear down the SCMI instance while the child still\nholds a handle into it.\n\nIf the protocol driver probe later fails, for example with\n-EPROBE_DEFER, the driver core emits BUS_NOTIFY_DRIVER_NOT_BOUND rather\nthan BUS_NOTIFY_UNBOUND_DRIVER. The SCMI notifier only released the\nhandle on BUS_NOTIFY_UNBOUND_DRIVER, so each failed protocol-device bind\nleaked the SCMI instance users refcount and left sdev->handle set after\nthe failed probe.\n\nMake the link helper report failure and drop the acquired handle if the\nlink cannot be created. Also handle BUS_NOTIFY_DRIVER_NOT_BOUND in the\nsame cleanup path used for unbind so failed probes balance the earlier\nBUS_NOTIFY_BIND_DRIVER acquisition."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/firmware/arm_scmi/driver.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "b50c9270304cfed6ee1c4ce5036102ad7b762051",
              "lessThan": "b5377e690cd4fe87ee52fcf067c9929414ea8f4e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "971fc0665f1361f23251e4d85fac4aed1b683505",
              "lessThan": "0f860db24ee95e5da4866303a35e55098b9641b3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "971fc0665f1361f23251e4d85fac4aed1b683505",
              "lessThan": "df273eced7cec550465fd1bb82a5d2c3c7d3c437",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "971fc0665f1361f23251e4d85fac4aed1b683505",
              "lessThan": "a54dc23e8bd2246c28eafffa60b4634f0d1a11cc",
              "versionType": "git",
              "status": "affected"
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            {
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              "lessThan": "77d2985d1e80e67f32026fc03e975c4c83cc543d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "971fc0665f1361f23251e4d85fac4aed1b683505",
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              "versionType": "git",
              "status": "affected"
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        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/firmware/arm_scmi/driver.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.3",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.3",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0f860db24ee95e5da4866303a35e55098b9641b3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/77d2985d1e80e67f32026fc03e975c4c83cc543d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a54dc23e8bd2246c28eafffa60b4634f0d1a11cc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b5377e690cd4fe87ee52fcf067c9929414ea8f4e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/df273eced7cec550465fd1bb82a5d2c3c7d3c437",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e3a5c30d233ca5d3e799a80da806554c703bda13",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}