{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-92525",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-92525"
  ],
  "published": "2026-09-17T16:10:40Z",
  "summary": "RDMA/rxe: Validate num_sge/cur_sge before indexing wqe->dma.sge[]",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Validate num_sge/cur_sge before indexing wqe->dma.sge[]\n\nFor a user QP, qp->sq.queue is a ring the application writes directly,\nso rxe_post_send() takes the is_user branch and only schedules send_task\nwithout validating the WQE. rxe_requester() consumes it in place via\nreq_next_wqe() and calls copy_data(), which indexes\n&wqe->dma.sge[cur_sge] with the attacker-controlled num_sge/cur_sge.\nOnly the kernel path bounds num_sge (validate_send_wr()); the user WQE\nis never checked, so a local unprivileged user can post a WQE with an\nout-of-range cur_sge or oversized num_sge and force an out-of-bounds\nread of the per-WQE sge array in copy_data() (vmalloc OOB read, local\nDoS).\n\nBound num_sge to qp->sq.max_sge in rxe_requester() before use, the way\nget_srq_wqe() already guards SRQ entries, and bound cur_sge only when\nthe WQE carries payload (dma.resid): copy_data() returns early on a\nzero-length copy before touching dma->sge[], so a zero-payload WQE --\nthe only kind a max_sge == 0 QP can post -- stays valid.\n\nReproduced under KASAN; the vmalloc-out-of-bounds in copy_data() is gone.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/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": "6.1.188",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-92525"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/69d3ccf6543f24c452a020c8028ca6f46cb1e8db"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/750bba6ce9bb0b11d6a166031c9728ae3f21765e"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c067aa7b231e91a18a1b3666201ab14dfb00347a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/13cb7160e5b791f5e3ecf9311cf32849fe7e9b62"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5ec111ddc1f727c1e4580aea459842ae5a8359a5"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/126c757e4cd46f866ddc283143b58eb4d9bf52cd"
    }
  ],
  "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": 7.1,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The attacker writes dma.num_sge/dma.cur_sge into the mmap'd send queue (rxe_init_sq\u2192vmalloc_user, rxe_mmap); ib_uverbs_post_send only doorbells rxe_post_send, which for qp->is_user skips validate_send_wr() and schedules rxe_requester(). Inbound RoCE/UDP packets do not carry these WQE index fields.\nAC:L - The attacker fully controls the mmap'd SQ slot (cur_sge, num_sge, resid, opcode) and the producer_index, then issues IB_USER_VERBS_CMD_POST_SEND; rxe_requester\u2192finish_packet\u2192copy_data indexes sge[] with no race and no victim-side state.\nPR:L - uverbs_devnode() publishes /dev/infiniband/uverbsN as 0666; ib_uverbs_open, ib_uverbs_create_qp, ib_uverbs_modify_qp and ib_uverbs_post_send require no capability for IB_QPT_UD/RC, so an unprivileged local user can create a user QP, mmap the SQ and post the malformed WQE.\nUI:N - The attacker creates their own user QP, writes the malformed send WQE into their mmap'd SQ and doorbells post_send; no other user must mount, open a file, or otherwise act.\nS:U - The vmalloc OOB in copy_data() runs in the host kernel rxe requester on behalf of the local process and does not cross a VM, guest-to-host, or IOMMU/DMA authority boundary.\nC:H - copy_data() does &dma->sge[dma->cur_sge] with attacker-controlled u32 cur_sge/num_sge into the vmalloc SQ and then reads sge->length/lkey/addr; an oversized num_sge also lets the sge++ loop walk unbounded kernel vmalloc (KASAN vmalloc-out-of-bounds).\nI:N - finish_packet() calls copy_data(..., RXE_FROM_MR_OBJ), which only reads MR contents into the SKB; the OOB is a read of sge descriptors, dma updates stay in the attacker's mmap'd WQE, and lookup_mr/rxe_mr_copy remain confined to MRs in the caller's PD.\nA:H - Indexing &wqe->dma.sge[cur_sge] past the vmalloc_user send-queue object is a KASAN-reproduced vmalloc-out-of-bounds in copy_data() that oopses/panics the kernel."
    }
  }
}