{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-80854",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-80854"
  ],
  "published": "2026-09-04T15:53:40Z",
  "summary": "usb: gadget: f_tcm: keep port count until LUN teardown completes",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_tcm: keep port count until LUN teardown completes\n\ntcm_usbg_drop_nexus() permits session removal once tpg_port_count\nreaches zero. However, usbg_port_unlink() currently decrements that\ncount from the fabric_pre_unlink() callback, before core_dev_del_lun()\nwaits for active se_lun references to drain.\n\nIf removal of the last LUN races a nexus removal, the latter can observe\na zero port count and call target_remove_session(). This frees\nsess_cmd_map while an in-flight struct usbg_cmd, including its work item,\ncan still be accessed.\n\nOverlapping the last-LUN unlink with nexus removal reproduces this\nlifetime violation as a DEBUG_OBJECTS \"free active\" warning for\nusbg_cmd_work, followed by a target-core BUG/Oops.\n\nThe generic target-core unlink path has no callback after\ncore_dev_del_lun() completes. Add an optional fabric_post_unlink()\ncallback and use it for the f_tcm port count. The count now remains\nnonzero until core_dev_del_lun() has finished draining active LUN\nreferences, preventing nexus removal from freeing the session during\ncommand completion.",
  "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-2026-80854"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c494c5562ca69b61a82f566e3b87a445d2c28929"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c1f359d9a5efed458946063de65ddbeaacc4f165"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/178f59a0bccd3f66cdfa5184310f31a58b7257c4"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ad6f0375d2e93a1d8c015463e5e92dfcb26e311b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2efbfd42441d3ef8137aff2d59e9835e1d5ae780"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/85aa61fedcb4eb13f3dc5db73f6dc359f41f5d95"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/bbd6aa311a9f4dd17822c7557451458d3d2e980b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/eaa96a8458f54d6cf0954242ab8b1df2a6fccafa"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c39d0916da47d94909391876c9e5bd429ea7b1b9"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-04T15:53:40Z"
  }
}