{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-80789",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-80789"
  ],
  "published": "2026-09-04T15:14:07Z",
  "summary": "nvmet-tcp: bound SGL data length before allocating command buffers",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvmet-tcp: bound SGL data length before allocating command buffers\n\nnvmet_tcp_map_data() reads the host-controlled 32-bit sgl->length\nand, for the in-capsule offset descriptor (type 0x01), checks it\nagainst port->inline_data_size before use. Any other SGL descriptor\ntype -- including the non-inline transport SGL data-block descriptor\n(type (NVME_TRANSPORT_SGL_DATA_DESC << 4) | NVME_SGL_FMT_TRANSPORT_A,\nthe type a real host uses for out-of-capsule writes) skips that check\nentirely and falls straight through to:\n\n\tcmd->req.sg = sgl_alloc(len, GFP_KERNEL, &cmd->req.sg_cnt);\n\nwith len taken directly from the wire, unbounded up to 4 GiB.\n\nnvmet_req_init() only parses the command and never inspects\nsgl->length, and nvmet_check_transfer_len() -- the only other place\ntransfer_len is validated -- runs later, from req->execute(), after\nthe allocation has already happened. For a write command the target\nresponds with an R2T and parks the command waiting for the host to\nsend the data; if the host (or an unauthenticated peer that simply\nnever follows up) never does, the sgl_alloc() buffer stays resident\nfor the life of the command. NVMe/TCP has no mandatory authentication\nin the default configuration, so any peer able to reach the target\nportal and complete a Fabrics connect can drive this with a single\ncrafted command, repeatable across queues and connections for\namplification. This is unbounded kernel memory allocation\ntriggered by a remote, effectively unauthenticated peer.\n\nValidate len against the same NVMET_TCP_MAXH2CDATA ceiling this file\nalready uses to bound per-PDU H2C data, for every SGL descriptor type,\nbefore doing any allocation. This closes the gap for the non-inline\ndescriptor while leaving the existing, tighter inline_data_size check\nin place for the in-capsule case.\n\nRuntime-verified on a v6.19 KASAN stand: with this bound in place, a\ncrafted write command carrying an oversized non-inline SGL length is\nrejected before sgl_alloc() runs, where the same request previously\ndrove an unbounded ~256 MiB kernel allocation (up to 4 GiB) that\nstayed resident pending an R2T the host never satisfies.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.187",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-80789"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f6e51b09cbaa5f6f6e6a3a9dafa666f76c37aab5"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f63e89a0310264264923f84406dea05fe752de62"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0952541b153e258b99d39cdb03ea6919fdeb41d0"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/25ad03d5c0e858c4b63f1e4b6d461d2af1b30b22"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d2acc96c528d589f5827cfb90e8e9229dd9d8cb4"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6d27199ebe8cb223022150f74be13f154a964474"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/14dbe37681a6a7e346fc147bb363ec7cca3180a0"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d895e66628f939edbb98608f6e033d3d39e6e546"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/4a3f00262a044e8e15064b1a6860968bf0500bf4"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-04T15:14:07Z"
  }
}