{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-98252",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-98252"
  ],
  "published": "2026-10-06T08:47:10Z",
  "summary": "RDMA/core: fix refcount bug in iwpm_get_nlmsg_request()",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/core: fix refcount bug in iwpm_get_nlmsg_request()\n\niwpm_get_nlmsg_request() initializes refcount _after_ list_add_tail()\nmaking it accessible to global list where another CPU can kref_get()\non nlmsg_request causing a refcount \"addition on 0\" bug. Fix this\nby initializing kref _before_ list_add_tail() so refcount for\nnlmsg_request can be incremented/decremented normally. In addition,\nalso initialize every field before list_add_tail().",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H"
    }
  ],
  "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": "6.1.189",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-98252"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/52c13c63bb3662c108244e7447055e30bf40244e"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8a91609032d47e77bcb37bc8f6e88d89340d2709"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ce8a379598bd4058081416abea4279fd05a95374"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2fbac8a56004b6ce54fbfe845d4b25da6e0b55e8"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/88e429a4e9bac3d2138011c5ca06254331f2587f"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/e15eb536be4f646ce683d2867572b2200be877f7"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/117871cdb8927542abd7b65ce5995bf0265a8c05"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/33fb59da49c4c3f5c2ec9f9d4447a56857a02c02"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-10-07T06:50:27Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.0,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The triggering input is a forged IWPM reply (e.g. RDMA_NL_IWPM_REG_PID) sent over a local NETLINK_RDMA socket to iwcm_nl_cb_table callbacks, which call iwpm_find_nlmsg_request(). No remote protocol carries it, and rdma_nl_rcv_msg() rejects RDMA_NL_IWCM messages from outside init_net.\nAC:H - The forged reply must land in the few-instruction gap between list_add_tail() and kref_init()/sema_init() in iwpm_get_nlmsg_request(). The host also needs an iWARP device so that iw_cm_map() sends port-mapper requests, and the attacker cannot set that up.\nPR:L - No iwcm_nl_cb_table entry sets RDMA_NL_ADMIN_PERM, and the NETLINK_RDMA socket uses NL_CFG_F_NONROOT_RECV, so an unprivileged user in the initial netns can join RDMA_NL_GROUP_IWPM, read the sequence numbers and send replies. A local login is still needed.\nUI:N - The attacker sends the netlink replies and starts iWARP connection setup without any action from another user.\nS:U - The memory corruption stays inside the kernel's own security authority. No guest/host or IOMMU boundary is crossed.\nC:H - kref_init() erases the reference taken by iwpm_find_nlmsg_request(), so the requester's kref_put() in iwpm_wait_complete_req() can free the kmalloc'd iwpm_nlmsg_request while iwpm_register_pid_cb() still uses it. That is a use-after-free that can be reclaimed by sprayed data.\nI:H - After the early free, the callback's up(&nlmsg_request->sem) and the requester's down_timeout() write a semaphore inside a freed and possibly reclaimed slab object. That is a use-after-free write on heap memory.\nA:H - The race fires a refcount_t 'addition on 0' WARN (a panic under panic_on_warn), and the replies can dereference NULL req_buffer in iwpm_register_pid_cb() or touch freed memory, either of which oopses the kernel."
    }
  }
}