FKIE_CVE-2025-40124

Vulnerability from fkie_nvd - Published: 2025-11-12 11:15 - Updated: 2026-10-19 21:10
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC III Anthony Yznaga tracked down that a BUG_ON in ext4 code with large folios enabled resulted from copy_from_user() returning impossibly large values greater than the size to be copied. This lead to __copy_from_iter() returning impossible values instead of the actual number of bytes it was able to copy. The BUG_ON has been reported in https://lore.kernel.org/r/b14f55642207e63e907965e209f6323a0df6dcee.camel@physik.fu-berlin.de The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. The exception handlers expect that %o2 has already been masked during the bulk copy loop, but the masking was performed after that loop. This will fix the return value of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1198077606aeffb102587c6ea079ce99641c99d4
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1857cdca12c4aff58bf26a7005a4d02850c29927
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/47b49c06eb62504075f0f2e2227aee2e2c2a58b3
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5ef9c94d7110e90260c06868cf1dcf899b9f25ee
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/91eda032eb16e5d2be27c95584665bc555bb5a90
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/dc766c4830a7e1e1ee9d7f77d4ab344f2eb23c8e
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e50377c6b3f278c9f3ef017ffce17f5fcc9dace4
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fdd43fe6d286f27b826572457a89c926f97e2d3a
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/sparc/lib/U3memcpy.S"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "fdd43fe6d286f27b826572457a89c926f97e2d3a",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "lessThan": "1198077606aeffb102587c6ea079ce99641c99d4",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "lessThan": "1857cdca12c4aff58bf26a7005a4d02850c29927",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "lessThan": "91eda032eb16e5d2be27c95584665bc555bb5a90",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "lessThan": "dc766c4830a7e1e1ee9d7f77d4ab344f2eb23c8e",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "lessThan": "5ef9c94d7110e90260c06868cf1dcf899b9f25ee",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "lessThan": "e50377c6b3f278c9f3ef017ffce17f5fcc9dace4",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "lessThan": "47b49c06eb62504075f0f2e2227aee2e2c2a58b3",
              "status": "affected",
              "version": "ee841d0aff649164080e445e84885015958d8ff4",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "1c7e17b1c4d60cc5aa575460f7efb73686dd3b39",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "ac663c54f40b2830b1ca32d1ae9d683fe248b14c",
              "versionType": "git"
            },
            {
              "lessThan": "4.5",
              "status": "affected",
              "version": "4.4.34",
              "versionType": "semver"
            },
            {
              "lessThan": "4.9",
              "status": "affected",
              "version": "4.8.10",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/sparc/lib/U3memcpy.S"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.9"
            },
            {
              "lessThan": "4.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.301",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.246",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.195",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.156",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.112",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.53",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18",
              "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\nsparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC III\n\nAnthony Yznaga tracked down that a BUG_ON in ext4 code with large folios\nenabled resulted from copy_from_user() returning impossibly large values\ngreater than the size to be copied. This lead to __copy_from_iter()\nreturning impossible values instead of the actual number of bytes it was\nable to copy.\n\nThe BUG_ON has been reported in\nhttps://lore.kernel.org/r/b14f55642207e63e907965e209f6323a0df6dcee.camel@physik.fu-berlin.de\n\nThe referenced commit introduced exception handlers on user-space memory\nreferences in copy_from_user and copy_to_user. These handlers return from\nthe respective function and calculate the remaining bytes left to copy\nusing the current register contents. The exception handlers expect that\n%o2 has already been masked during the bulk copy loop, but the masking was\nperformed after that loop. This will fix the return value of copy_from_user\nand copy_to_user in the faulting case. The behaviour of memcpy stays\nunchanged."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nsparc: corregir el informe preciso de excepciones en copy_{from_to}_user para UltraSPARC III\n\nAnthony Yznaga descubri\u00f3 que un BUG_ON en el c\u00f3digo ext4 con folios grandes habilitados resultaba de que copy_from_user() devolviera valores imposiblemente grandes, mayores que el tama\u00f1o a copiar. Esto llev\u00f3 a que __copy_from_iter() devolviera valores imposibles en lugar del n\u00famero real de bytes que pudo copiar.\n\nEl BUG_ON ha sido reportado en https://lore.kernel.org/r/b14f55642207e63e907965e209f6323a0df6dcee.camel@physik.fu-berlin.de\n\nEl commit referenciado introdujo manejadores de excepciones en referencias de memoria de espacio de usuario en copy_from_user y copy_to_user. Estos manejadores regresan de la funci\u00f3n respectiva y calculan los bytes restantes por copiar utilizando el contenido actual del registro. Los manejadores de excepciones esperan que %o2 ya haya sido enmascarado durante el bucle de copia masiva, pero el enmascaramiento se realiz\u00f3 despu\u00e9s de ese bucle. Esto corregir\u00e1 el valor de retorno de copy_from_user y copy_to_user en el caso de fallo. El comportamiento de memcpy permanece sin cambios."
    }
  ],
  "id": "CVE-2025-40124",
  "lastModified": "2026-10-19T21:10:00.160",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2025-11-12T11:15:41.920",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1198077606aeffb102587c6ea079ce99641c99d4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1857cdca12c4aff58bf26a7005a4d02850c29927"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/47b49c06eb62504075f0f2e2227aee2e2c2a58b3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5ef9c94d7110e90260c06868cf1dcf899b9f25ee"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/91eda032eb16e5d2be27c95584665bc555bb5a90"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/dc766c4830a7e1e1ee9d7f77d4ab344f2eb23c8e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e50377c6b3f278c9f3ef017ffce17f5fcc9dace4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fdd43fe6d286f27b826572457a89c926f97e2d3a"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Deferred"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.