{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "3e980f5995e0bb4d86fef873a9c9ad66721580d0"
            },
            {
              "fixed": "2c23fc91789dfd9db746edb3ae9b90d65fabd410"
            },
            {
              "fixed": "f1a8846e06388113dfdbb89dee005083fa9afdf9"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.1.0"
            },
            {
              "fixed": "7.2.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90206.json"
  },
  "details": "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-\u003esqs = kzalloc_objs(struct nvmet_sq *, subsys-\u003emax_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-\u003ectrls list yet.\n\nnvmet_alloc_ctrl() then proceeds and adds the new controller to the\nsubsys-\u003ectrls 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(\u0026nvmet_config_sem). Because\nnvmet_subsys_attr_qid_max_store() acquires down_write(\u0026nvmet_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-\u003emax_qid never changes as long as the\ncontroller remains in LIVE state, so this will prevent similar race\nconditions.",
  "id": "CVE-2026-90206",
  "modified": "2026-09-19T03:30:45.839570831Z",
  "published": "2026-09-17T16:07:22.173Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2c23fc91789dfd9db746edb3ae9b90d65fabd410"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f1a8846e06388113dfdbb89dee005083fa9afdf9"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90206.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90206"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "nvmet: fix max_qid race between configfs and controller allocation"
}