{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "9ef4cbbcb4ac3786a1a4164507511b76b2a572c5"
            },
            {
              "fixed": "45c945107e007b1fb73e21cd220277652a45521a"
            },
            {
              "fixed": "6b308c37fbeba3aa8c634fb1ed53e2f63a5d5a5c"
            },
            {
              "fixed": "3267d7c8ba51642117f7bdd1ece02b2540668476"
            },
            {
              "fixed": "3f3a6a16bbe8bde76532d9415438f8cdef439e5d"
            }
          ],
          "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-2026-80810.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/rsrc: fix folio size overflow in io_vec_fill_bvec()\n\nio_vec_fill_bvec() computes the folio size with a plain int 1:\n\n\tunsigned long folio_size = 1 \u003c\u003c imu-\u003efolio_shift;\n\nimu-\u003efolio_shift is unsigned int and comes from folio_shift() of the\nfolio backing the registered buffer, so it can be 32 or more on a 64 bit\nkernel. Shifting int 1 that far is undefined, and on x86 and arm64 the\ncount is taken modulo 32, so a shift of 34 yields 4 rather than 16G.\nEvery other folio_shift shift in this file already uses 1UL.\n\nThe result is that the segment estimate and the fill loop disagree.\nio_estimate_bvec_size() sizes the bvec array with the real shift:\n\n\tmax_segs += (iov[i].iov_len \u003e\u003e shift) + 2;\n\nso a 1M iovec on a 16G folio is charged 2 segments, while\nio_vec_fill_bvec() then walks the same iovec in folio_size chunks of 4\nbytes and writes res_bvec[bvec_idx] a quarter of a million times, past\nthe end of the array it was given. src_bvec is advanced once per\niteration as well, so imu-\u003ebvec is read past its end at the same time.\nvalidate_fixed_range() only checks that the range is inside the\nregistered buffer and does not bound the segment count.\n\nReaching it needs a folio with a shift of at least 32, which means a\ngigantic hugetlb page: 16G on arm64 with 64K pages, where\nCONT_PMD_SHIFT is 34 and hugetlb_add_hstate(CONT_PMD_SHIFT - PAGE_SHIFT)\nregisters that size, and likewise on powerpc. x86_64 tops out at 1G, so\na shift of 30, which still fits in int and is unaffected.\n\nUse 1UL, as the rest of the file does.",
  "id": "CVE-2026-80810",
  "modified": "2026-09-06T03:30:26.163857643Z",
  "published": "2026-09-04T15:13:30.800Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3267d7c8ba51642117f7bdd1ece02b2540668476"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3f3a6a16bbe8bde76532d9415438f8cdef439e5d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/45c945107e007b1fb73e21cd220277652a45521a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6b308c37fbeba3aa8c634fb1ed53e2f63a5d5a5c"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80810.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80810"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "io_uring/rsrc: fix folio size overflow in io_vec_fill_bvec()"
}