{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-93154",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-93154"
  ],
  "published": "2026-09-17T16:10:40Z",
  "summary": "RDMA/irdma: Add refcounting to user ring MRs",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/irdma: Add refcounting to user ring MRs\n\nPrevent userspace from deregistering the MRs that back QP/CQ/SRQ rings\nby bumping the MR's refcount upon association.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/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": null,
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-93154"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/07974c267f603a76aead348bca97deee95efdcc9"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a6c0e693a7c881bfa43ac74cbcad1f8e10f1382b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f67d8a08f60c9217df6d40da56422d2049f5e334"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-18T17:55:42Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The trigger is a local IB_USER_VERBS_CMD_DEREG_MR write (ib_uverbs_dereg_mr / UVERBS_METHOD_MR_DESTROY) on /dev/infiniband/uverbs*. After irdma_get_pbl binds an IRDMA_MEMREG_TYPE_QP/CQ/SRQ ring MR to a live QP/CQ/SRQ, irdma_dereg_mr still frees it; no iWARP/RoCE message supplies that deregistration.\nAC:L - The attacker drives every step with no race: irdma_reg_user_mr with reg_type QP/CQ/SRQ, then irdma_setup_umode_qp/irdma_create_cq/irdma_setup_umode_srq so irdma_get_pbl sets on_list=false, then irdma_dereg_mr. Pre-fix irdma_del_memlist is a no-op on an already-associated ring, so the free is deterministic.\nPR:L - ib_uverbs_open() only checks rdma_dev_access_netns() (devices shared across netns by default) and ib_uverbs_dereg_mr() only requires ownership of the caller's MR uobject, with no capability gate. rdma-core udev rules expose uverbs as 0666; a small ring fits unprivileged RLIMIT_MEMLOCK without CAP_IPC_LOCK.\nUI:N - The attacker registers the ring MR via ib_uverbs_reg_mr, creates the QP/CQ/SRQ, and issues IB_USER_VERBS_CMD_DEREG_MR on that handle from their own process; no other user must mount a device, open a file, or otherwise act.\nS:U - irdma_dereg_mr kfree()s the irdma_mr and releases its umem/HMC PBLEs while the same host's QP/CQ/SRQ still holds iwpbl and the NIC still DMAs those rings. That is host-kernel memory corruption, not a KVM/Xen guest-to-host escape or an IOMMU isolation bypass.\nC:H - irdma_dereg_mr calls ib_umem_release, irdma_free_pble, and kfree(iwmr) while hardware still walks those HMC PBLEs and DMA-reads SQ/RQ/CQ rings. Recycled umem pages and PBLE tables yield device DMA reads of kernel or other-process memory, and iwqp/iwcq->iwpbl dangles into the freed irdma_mr.\nI:H - The NIC keeps DMAing CQEs/WQEs into unpinned, reallocatable ring pages and walking freed PBLE page tables, producing device writes into recycled kernel memory. Combined with the irdma_mr heap UAF (struct irdma_pbl iwpbl is embedded in iwmr), this is an arbitrary-write primitive.\nA:H - kfree of a still-referenced irdma_mr, irdma_free_pble of live HMC page tables, and DMA into unmapped SQ/RQ/CQ pages cause a kernel oops/panic or an irdma CQP/device reset when the QP/CQ/SRQ is next used or destroyed."
    }
  }
}