FKIE_CVE-2026-31420

Vulnerability from fkie_nvd - Published: 2026-04-13 14:16 - Updated: 2026-04-13 15:01
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: bridge: mrp: reject zero test interval to avoid OOM panic br_mrp_start_test() and br_mrp_start_in_test() accept the user-supplied interval value from netlink without validation. When interval is 0, usecs_to_jiffies(0) yields 0, causing the delayed work (br_mrp_test_work_expired / br_mrp_in_test_work_expired) to reschedule itself with zero delay. This creates a tight loop on system_percpu_wq that allocates and transmits MRP test frames at maximum rate, exhausting all system memory and causing a kernel panic via OOM deadlock. The same zero-interval issue applies to br_mrp_start_in_test_parse() for interconnect test frames. Use NLA_POLICY_MIN(NLA_U32, 1) in the nla_policy tables for both IFLA_BRIDGE_MRP_START_TEST_INTERVAL and IFLA_BRIDGE_MRP_START_IN_TEST_INTERVAL, so zero is rejected at the netlink attribute parsing layer before the value ever reaches the workqueue scheduling code. This is consistent with how other bridge subsystems (br_fdb, br_mst) enforce range constraints on netlink attributes.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c9bc352f716d1bebfe43354bce539ec2d0223b30
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fa6e24963342de4370e3a3c9af41e38277b74cf3
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{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-31420",
  "lastModified": "2026-04-13T15:01:43.663",
  "metrics": {},
  "published": "2026-04-13T14:16:11.617",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c9bc352f716d1bebfe43354bce539ec2d0223b30"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fa6e24963342de4370e3a3c9af41e38277b74cf3"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}


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