{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "3a4689ac109f18f23ea0d0c1c79e055142796858"
            },
            {
              "fixed": "b6a768aa975b9ca81b92f028bdd975d1f8237894"
            },
            {
              "fixed": "b290de4d16d75b6c1ef42025b47f5d94eb1ec09f"
            },
            {
              "fixed": "7068d3587a64a24943a7c9e232976da2c9e0e303"
            },
            {
              "fixed": "bb34ae5da3365699d53a756f4c96b6ea9f8ba0c1"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.15.0"
            },
            {
              "fixed": "6.18.47"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.11"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "7.2.0"
            },
            {
              "fixed": "7.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80811.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/cmd: fix iovec leak when the async cmd is not recycled\n\nAn io_async_cmd carries an iovec array in -\u003evec.iovec, allocated when the\nvec has to grow and kept across recycling through ctx-\u003ecmd_cache.  On two\npaths nothing frees it and io_clean_op()'s kfree(req-\u003easync_data) drops\nthe io_async_cmd without it.\n\nio_req_uring_cleanup() clears the async data flags only when\nio_alloc_cache_put() succeeds, and the cache holds IO_ALLOC_CACHE_MAX ==\n128 entries, so once it is full the put fails and the vec is left behind.\nAn NVMe passthrough workload gets there without doing anything unusual:\nnvme_uring_cmd_io() returns -EIOCBQUEUED, so the io_async_cmd stays\nattached for the lifetime of the command and the live object count tracks\nthe queue depth.  Above 128 the puts start failing.\n\n-\u003ecleanup is the last chance to free an inherited vec, since\nio_req_uring_cleanup() returns early for an io-wq issued command and is\nnot called at all for one completed without ever being issued.  But\nio_clean_op() calls -\u003ecleanup only if REQ_F_NEED_CLEANUP is set, and for\nuring_cmd that happens only where the vec has to grow, so a command\nreusing a large enough cached vec never sets it.  io_rw_alloc_async() and\nio_msg_alloc_async() flag an inherited vec for exactly this reason;\nio_uring_cmd_prep() does not.\n\nFlag an inherited vec in io_uring_cmd_prep(), and free the vec when the\ncache put fails, as io_req_rw_cleanup() does.\n\nThe leak is invisible under KASAN, where io_alloc_cache_vec_kasan() frees\nthe vec unconditionally.",
  "id": "CVE-2026-80811",
  "modified": "2026-09-06T03:30:40.261602978Z",
  "published": "2026-09-04T15:13:31.761Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7068d3587a64a24943a7c9e232976da2c9e0e303"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b290de4d16d75b6c1ef42025b47f5d94eb1ec09f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b6a768aa975b9ca81b92f028bdd975d1f8237894"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bb34ae5da3365699d53a756f4c96b6ea9f8ba0c1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80811.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80811"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "io_uring/cmd: fix iovec leak when the async cmd is not recycled"
}