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CVE-2026-72469

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Fix ep kref imbalance on ADDR_CHANGE rpcrdma_cm_event_handler() falls through to the disconnected: label on RDMA_CM_EVENT_ADDR_CHANGE and calls rpcrdma_ep_put() with no matching get when the event arrives before RDMA_CM_EVENT_ESTABLISHED. The kref then underflows during connect teardown and rpcrdma_xprt_disconnect() operates on a freed ep. Reference counts across a normal connection lifecycle: rpcrdma_ep_create() kref_init ->1 rpcrdma_xprt_connect() ep_get ->2 (before post_recvs) RDMA_CM_EVENT_ESTABLISHED ep_get ->3 RDMA_CM_EVENT_DISCONNECTED ep_put ->2 rpcrdma_xprt_drain() ep_put ->1 rpcrdma_xprt_disconnect() tail ep_put ->0 (ep_destroy) The connect-time get in rpcrdma_xprt_connect(), taken just before rpcrdma_post_recvs() "while there are outstanding Receives," is balanced by rpcrdma_xprt_drain. ADDR_CHANGE before ESTABLISHED has no get to consume, so its put drops the count to 1 and the drain put then frees the ep while rpcrdma_xprt_disconnect() still holds a pointer to it. Fix by dispatching on the prior re_connect_status via xchg(): for prev == 0 (pre-ESTABLISHED) wake the connect waiter and return with no put; for prev == 1 call rpcrdma_force_disconnect() and return. The case-1 arm relies on the subsequent RDMA_CM_EVENT_DISCONNECTED event -- reliably delivered when rdma_disconnect() is called on a still-connected cm_id -- to balance the ESTABLISHED get; rpcrdma_xprt_drain() continues to balance only that connect-time get. Any other prior value means teardown is already in flight.

Severity
HIGH
CVSS score
8.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-15 06:22:20.997000
Last modified
2026-10-21 13:19:38.600000
View original CVE JSON
{
  "id": "CVE-2026-72469",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-15T06:22:20.997",
  "lastModified": "2026-10-21T13:19:38.600",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxprtrdma: Fix ep kref imbalance on ADDR_CHANGE\n\nrpcrdma_cm_event_handler() falls through to the disconnected: label\non RDMA_CM_EVENT_ADDR_CHANGE and calls rpcrdma_ep_put() with no\nmatching get when the event arrives before RDMA_CM_EVENT_ESTABLISHED.\nThe kref then underflows during connect teardown and\nrpcrdma_xprt_disconnect() operates on a freed ep.\n\nReference counts across a normal connection lifecycle:\n\n    rpcrdma_ep_create()             kref_init     ->1\n    rpcrdma_xprt_connect()          ep_get        ->2  (before post_recvs)\n    RDMA_CM_EVENT_ESTABLISHED       ep_get        ->3\n    RDMA_CM_EVENT_DISCONNECTED      ep_put        ->2\n    rpcrdma_xprt_drain()            ep_put        ->1\n    rpcrdma_xprt_disconnect() tail  ep_put        ->0  (ep_destroy)\n\nThe connect-time get in rpcrdma_xprt_connect(), taken just before\nrpcrdma_post_recvs() \"while there are outstanding Receives,\" is\nbalanced by rpcrdma_xprt_drain. ADDR_CHANGE before ESTABLISHED has\nno get to consume, so its put drops the count to 1 and the drain\nput then frees the ep while rpcrdma_xprt_disconnect() still holds a\npointer to it.\n\nFix by dispatching on the prior re_connect_status via xchg(): for\nprev == 0 (pre-ESTABLISHED) wake the connect waiter and return with\nno put; for prev == 1 call rpcrdma_force_disconnect() and return.\nThe case-1 arm relies on the subsequent RDMA_CM_EVENT_DISCONNECTED\nevent -- reliably delivered when rdma_disconnect() is called on a\nstill-connected cm_id -- to balance the ESTABLISHED get;\nrpcrdma_xprt_drain() continues to balance only that connect-time\nget. Any other prior value means teardown is already in flight."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/sunrpc/xprtrdma/verbs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "lessThan": "a562485c359d0b20a99d466b042af9c2f7ff3326",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "lessThan": "cfd1bab66b042da7a778786685125656c695931b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "lessThan": "d0479c2b12974aa188b10d221a5770126b118b6d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "lessThan": "ffc07790539736a5d029f6a3c966b46c529f93a8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "lessThan": "af9b65b29af341932625c4283dc7a23cdb62688a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2fcbf07a4f23174a45e015b62a8e42ddbc2e53ef",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5.7.9",
              "lessThan": "5.8",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/sunrpc/xprtrdma/verbs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.8",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.8",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.97",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.40",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.5",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T18:50:27.416569Z",
          "id": "CVE-2026-72469",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/a562485c359d0b20a99d466b042af9c2f7ff3326",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/af9b65b29af341932625c4283dc7a23cdb62688a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cfd1bab66b042da7a778786685125656c695931b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d0479c2b12974aa188b10d221a5770126b118b6d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ffc07790539736a5d029f6a3c966b46c529f93a8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}