CVE-2026-90206

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: nvmet: fix max_qid race between configfs and controller allocation The function nvmet_subsys_attr_qid_max_store() can race against nvmet_alloc_ctrl() when a subsystem's max_qid limit is modified. Suppose max_qid is currently 64. If nvmet_alloc_ctrl() executes: ctrl->sqs = kzalloc_objs(struct nvmet_sq *, subsys->max_qid + 1); and at this exact point, a userspace process changes max_qid to 128, nvmet_subsys_attr_qid_max_store() will set the new max_qid value. It attempts to delete active controllers to force a reconnect, but the new controller won't be deleted because it hasn't been added to the subsys->ctrls list yet. nvmet_alloc_ctrl() then proceeds and adds the new controller to the subsys->ctrls list. Later, when nvmet_install_queue() is called, it will see max_qid set to 128, but the memory allocated for sqs is only sized for 64 entries. This results in a KASAN out-of-bounds warning and potential memory corruptions. Fix this by protecting the queue allocations and list insertion in nvmet_alloc_ctrl() with down_read(&nvmet_config_sem). Because nvmet_subsys_attr_qid_max_store() acquires down_write(&nvmet_config_sem) to modify the attribute, this safely prevents the configfs writer from modifying max_qid during controller creation. Copy the max_qid from the subsystem to the controller's structure during the allocation; ctrl->max_qid never changes as long as the controller remains in LIVE state, so this will prevent similar race conditions.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

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

Published

2026-09-17 17:17:15.700000

Last modified

2026-10-30 13:20:46.387000

View original CVE JSON

{
  "id": "CVE-2026-90206",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:17:15.700",
  "lastModified": "2026-10-30T13:20:46.387",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvmet: fix max_qid race between configfs and controller allocation\n\nThe function nvmet_subsys_attr_qid_max_store() can race against\nnvmet_alloc_ctrl() when a subsystem's max_qid limit is modified.\n\nSuppose max_qid is currently 64. If nvmet_alloc_ctrl() executes:\nctrl->sqs = kzalloc_objs(struct nvmet_sq *, subsys->max_qid + 1);\nand at this exact point, a userspace process changes max_qid to 128,\nnvmet_subsys_attr_qid_max_store() will set the new max_qid value. It\nattempts to delete active controllers to force a reconnect, but the\nnew controller won't be deleted because it hasn't been added to the\nsubsys->ctrls list yet.\n\nnvmet_alloc_ctrl() then proceeds and adds the new controller to the\nsubsys->ctrls list. Later, when nvmet_install_queue() is called, it\nwill see max_qid set to 128, but the memory allocated for sqs is only\nsized for 64 entries. This results in a KASAN out-of-bounds warning\nand potential memory corruptions.\n\nFix this by protecting the queue allocations and list insertion in\nnvmet_alloc_ctrl() with down_read(&nvmet_config_sem). Because\nnvmet_subsys_attr_qid_max_store() acquires down_write(&nvmet_config_sem)\nto modify the attribute, this safely prevents the configfs writer from\nmodifying max_qid during controller creation.\n\nCopy the max_qid from the subsystem to the controller's structure\nduring the allocation; ctrl->max_qid never changes as long as the\ncontroller remains in LIVE state, so this will prevent similar race\nconditions."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/nvme/target/admin-cmd.c",
            "drivers/nvme/target/core.c",
            "drivers/nvme/target/fabrics-cmd.c",
            "drivers/nvme/target/nvmet.h",
            "drivers/nvme/target/pci-epf.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3e980f5995e0bb4d86fef873a9c9ad66721580d0",
              "lessThan": "cae0f5ed6ce7af3f7e0003c417f1953a350f55bf",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e980f5995e0bb4d86fef873a9c9ad66721580d0",
              "lessThan": "af811970da4f0a928f5a1b1a946a04f755ce86f2",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e980f5995e0bb4d86fef873a9c9ad66721580d0",
              "lessThan": "a1b88a1782eb6b368071dcda548a41b5c23d8cd2",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e980f5995e0bb4d86fef873a9c9ad66721580d0",
              "lessThan": "6e6f8e3bfc66dff1833a48ecfd857268cff3be84",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e980f5995e0bb4d86fef873a9c9ad66721580d0",
              "lessThan": "2c23fc91789dfd9db746edb3ae9b90d65fabd410",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3e980f5995e0bb4d86fef873a9c9ad66721580d0",
              "lessThan": "f1a8846e06388113dfdbb89dee005083fa9afdf9",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/nvme/target/admin-cmd.c",
            "drivers/nvme/target/core.c",
            "drivers/nvme/target/fabrics-cmd.c",
            "drivers/nvme/target/nvmet.h",
            "drivers/nvme/target/pci-epf.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "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": "7.2.6",
              "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/2c23fc91789dfd9db746edb3ae9b90d65fabd410",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6e6f8e3bfc66dff1833a48ecfd857268cff3be84",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a1b88a1782eb6b368071dcda548a41b5c23d8cd2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/af811970da4f0a928f5a1b1a946a04f755ce86f2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cae0f5ed6ce7af3f7e0003c417f1953a350f55bf",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f1a8846e06388113dfdbb89dee005083fa9afdf9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}