FKIE_CVE-2026-74631

Vulnerability from fkie_nvd - Published: 2026-08-22 16:16 - Updated: 2026-10-14 13:10
Severity
8.4 (High) - CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net: smc: fix splice entry lifetime imbalance in smc_rx_splice smc_rx_splice() passes pages to splice_to_pipe() before taking the references that cover the lifetime of each splice entry. In the VM-backed RMB path, splice_to_pipe() may drop unqueued entries through smc_rx_spd_release(), while queued entries are released later via the pipe buffer callback. The old post-splice accounting also derives the number of queued VM pages from an offset mutated while building the descriptor, and a multi-page splice pairs one sock_hold() with multiple sock_put() calls. Take the page and socket references for every candidate entry before splice_to_pipe(), and drop the matching private state, page reference, and socket reference from smc_rx_spd_release() for entries that never get queued. This fixes a refcount imbalance that can underflow page refcounts and trigger a use-after-free.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/07ad246529d136d5ef441d5ab4c305d132ff3090
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0b7d54cedea5cb158e21925ae0c6c2f5c87ed2a0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4515c78f4d9fd577270f012efeb062ea58b3682d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5d9686af2976741bbd79b150d1c9e60b81e7f12e
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7ddc7af2ae7fc5a0c0635b245c0824c8b76de5cb
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/af02c67ce654356c58db20a0bb2db33ace3b07a8
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c841789e456ec6751342fa800639ce8e82ff0e6b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ca8342b5fc24c249fdb998468f6a168b457c67e5
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/smc/smc_rx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7ddc7af2ae7fc5a0c0635b245c0824c8b76de5cb",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            },
            {
              "lessThan": "07ad246529d136d5ef441d5ab4c305d132ff3090",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            },
            {
              "lessThan": "c841789e456ec6751342fa800639ce8e82ff0e6b",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            },
            {
              "lessThan": "af02c67ce654356c58db20a0bb2db33ace3b07a8",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            },
            {
              "lessThan": "ca8342b5fc24c249fdb998468f6a168b457c67e5",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            },
            {
              "lessThan": "0b7d54cedea5cb158e21925ae0c6c2f5c87ed2a0",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            },
            {
              "lessThan": "4515c78f4d9fd577270f012efeb062ea58b3682d",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            },
            {
              "lessThan": "5d9686af2976741bbd79b150d1c9e60b81e7f12e",
              "status": "affected",
              "version": "9014db202cb764b8e14c53e7bacc81f9a1a2ba7f",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/smc/smc_rx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.18"
            },
            {
              "lessThan": "4.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.266",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.217",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.152",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.104",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.45",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: smc: fix splice entry lifetime imbalance in smc_rx_splice\n\nsmc_rx_splice() passes pages to splice_to_pipe() before taking the\nreferences that cover the lifetime of each splice entry. In the\nVM-backed RMB path, splice_to_pipe() may drop unqueued entries through\nsmc_rx_spd_release(), while queued entries are released later via the\npipe buffer callback.\n\nThe old post-splice accounting also derives the number of queued VM pages\nfrom an offset mutated while building the descriptor, and a multi-page\nsplice pairs one sock_hold() with multiple sock_put() calls.\n\nTake the page and socket references for every candidate entry before\nsplice_to_pipe(), and drop the matching private state, page reference,\nand socket reference from smc_rx_spd_release() for entries that never\nget queued. This fixes a refcount imbalance that can underflow page\nrefcounts and trigger a use-after-free."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet: smc: corregir el desequilibrio en el tiempo de vida de la entrada de splice en smc_rx_splice\n\nsmc_rx_splice() pasa p\u00e1ginas a splice_to_pipe() antes de tomar las referencias que cubren el tiempo de vida de cada entrada de splice. En la ruta RMB respaldada por VM, splice_to_pipe() puede descartar entradas no encoladas a trav\u00e9s de smc_rx_spd_release(), mientras que las entradas encoladas se liberan m\u00e1s tarde a trav\u00e9s de la devoluci\u00f3n de llamada del b\u00fafer de tuber\u00eda.\n\nLa antigua contabilidad post-splice tambi\u00e9n deriva el n\u00famero de p\u00e1ginas VM encoladas de un desplazamiento mutado mientras se construye el descriptor, y un splice de varias p\u00e1ginas empareja una llamada a sock_hold() con m\u00faltiples llamadas a sock_put().\n\nTomar las referencias de p\u00e1gina y de socket para cada entrada candidata antes de splice_to_pipe(), y descartar el estado privado coincidente, la referencia de p\u00e1gina y la referencia de socket de smc_rx_spd_release() para las entradas que nunca se encolan. Esto corrige un desequilibrio en el contador de referencias que puede causar un desbordamiento negativo en los contadores de referencias de p\u00e1gina y desencadenar un uso despu\u00e9s de liberaci\u00f3n."
    }
  ],
  "id": "CVE-2026-74631",
  "lastModified": "2026-10-14T13:10:00.187",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 8.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-22T16:16:36.080",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/07ad246529d136d5ef441d5ab4c305d132ff3090"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0b7d54cedea5cb158e21925ae0c6c2f5c87ed2a0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4515c78f4d9fd577270f012efeb062ea58b3682d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5d9686af2976741bbd79b150d1c9e60b81e7f12e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7ddc7af2ae7fc5a0c0635b245c0824c8b76de5cb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/af02c67ce654356c58db20a0bb2db33ace3b07a8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c841789e456ec6751342fa800639ce8e82ff0e6b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ca8342b5fc24c249fdb998468f6a168b457c67e5"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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