{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-31420",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-31420"
  ],
  "published": "2026-04-13T13:41:05Z",
  "summary": "bridge: mrp: reject zero test interval to avoid OOM panic",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: mrp: reject zero test interval to avoid OOM panic\n\nbr_mrp_start_test() and br_mrp_start_in_test() accept the user-supplied\ninterval value from netlink without validation. When interval is 0,\nusecs_to_jiffies(0) yields 0, causing the delayed work\n(br_mrp_test_work_expired / br_mrp_in_test_work_expired) to reschedule\nitself with zero delay. This creates a tight loop on system_percpu_wq\nthat allocates and transmits MRP test frames at maximum rate, exhausting\nall system memory and causing a kernel panic via OOM deadlock.\n\nThe same zero-interval issue applies to br_mrp_start_in_test_parse()\nfor interconnect test frames.\n\nUse NLA_POLICY_MIN(NLA_U32, 1) in the nla_policy tables for both\nIFLA_BRIDGE_MRP_START_TEST_INTERVAL and\nIFLA_BRIDGE_MRP_START_IN_TEST_INTERVAL, so zero is rejected at the\nnetlink attribute parsing layer before the value ever reaches the\nworkqueue scheduling code. This is consistent with how other bridge\nsubsystems (br_fdb, br_mst) enforce range constraints on netlink\nattributes.",
  "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-2026-31420"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/610073ffb77ffd2b5eca182d2ac264de4834a175"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ec8850be9b2b3beac1c7967d95f169dd2785979d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/1ec86b4b9e28170a2565cf36f0e6e2b96b55134d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2120bd8546cd6a63c558d135773aa8f41c8259fc"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/630a15a31c2034b5b697f4aabc769b9d80d82446"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/e8ec80430bfa520e7352155d6ac632e527cba7aa"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c9bc352f716d1bebfe43354bce539ec2d0223b30"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fa6e24963342de4370e3a3c9af41e38277b74cf3"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-14T12:06:03Z"
  }
}