RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv

{
  "id": "764f503601f6426c8920c90520688f7b2ba2e2e7b732f77da36cc91b6e3d9781",
  "url": "https://osv.dev/vulnerability/CVE-2026-46043",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv rxe_rcv() currently checks only that the incoming packet is at least header_size(pkt) bytes long before payload_size() is used. However, payload_size() subtracts both the attacker-controlled BTH pad field and RXE_ICRC_SIZE from pkt->paylen: payload_size = pkt->paylen - offset[RXE_PAYLOAD] - bth_pad(pkt) - RXE_ICRC_SIZE This means a short packet can still make payload_size() underflow even if it includes enough bytes for the fixed headers. Simply requiring header_size(pkt) + RXE_ICRC_SIZE is not sufficient either, because a packet with a forged non-zero BTH pad can still leave payload_size() negative and pass an underflowed value to later receive-path users. Fix this by validating pkt->paylen against the full minimum length required by payload_size(): header_size(pkt) + bth_pad(pkt) + RXE_ICRC_SIZE.",
    "evidence": "osv:CVE-2026-46043",
    "products": [
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      "modified": "2026-10-28T02:30:39.624117065Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2c0d71ef12f46c57d37bc571f3f2797db7eb50cc",
        "https://git.kernel.org/stable/c/2fd4f8b749309a61c3f3f88ee8891d94f79e1240",
        "https://git.kernel.org/stable/c/5fedefec757192dcaad29a664ac332c7601be144",
        "https://git.kernel.org/stable/c/7244491dab347f648e661da96dc0febadd9daec3",
        "https://git.kernel.org/stable/c/9b924f3a26b21330a837cfe72e819b6393bbeeaa",
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        "https://git.kernel.org/stable/c/e8ee0e792d475b1067c199ef0af1b6221fa6f43d",
        "https://git.kernel.org/stable/c/f83519a4c122c9c7a850a2197648a9ff4c67c520",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46043.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-46043",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
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    "severity_evidence": "/severity/0/score"
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  "source_id": "core-osv",
  "document_id": 507241,
  "published_at": "2026-05-27T12:56:57.987+00:00"
}