GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

FKIE_CVE-2022-49067

Vulnerability from fkie_nvd - Published: 2025-02-26 07:00 - Updated: 2026-06-17 05:16
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit mpe: On 64-bit Book3E vmalloc space starts at 0x8000000000000000. Because of the way __pa() works we have: __pa(0x8000000000000000) == 0, and therefore virt_to_pfn(0x8000000000000000) == 0, and therefore virt_addr_valid(0x8000000000000000) == true Which is wrong, virt_addr_valid() should be false for vmalloc space. In fact all vmalloc addresses that alias with a valid PFN will return true from virt_addr_valid(). That can cause bugs with hardened usercopy as described below by Kefeng Wang: When running ethtool eth0 on 64-bit Book3E, a BUG occurred: usercopy: Kernel memory exposure attempt detected from SLUB object not in SLUB page?! (offset 0, size 1048)! kernel BUG at mm/usercopy.c:99 ... usercopy_abort+0x64/0xa0 (unreliable) __check_heap_object+0x168/0x190 __check_object_size+0x1a0/0x200 dev_ethtool+0x2494/0x2b20 dev_ioctl+0x5d0/0x770 sock_do_ioctl+0xf0/0x1d0 sock_ioctl+0x3ec/0x5a0 __se_sys_ioctl+0xf0/0x160 system_call_exception+0xfc/0x1f0 system_call_common+0xf8/0x200 The code shows below, data = vzalloc(array_size(gstrings.len, ETH_GSTRING_LEN)); copy_to_user(useraddr, data, gstrings.len * ETH_GSTRING_LEN)) The data is alloced by vmalloc(), virt_addr_valid(ptr) will return true on 64-bit Book3E, which leads to the panic. As commit 4dd7554a6456 ("powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses") does, make sure the virt addr above PAGE_OFFSET in the virt_addr_valid() for 64-bit, also add upper limit check to make sure the virt is below high_memory. Meanwhile, for 32-bit PAGE_OFFSET is the virtual address of the start of lowmem, high_memory is the upper low virtual address, the check is suitable for 32-bit, this will fix the issue mentioned in commit 602946ec2f90 ("powerpc: Set max_mapnr correctly") too. On 32-bit there is a similar problem with high memory, that was fixed in commit 602946ec2f90 ("powerpc: Set max_mapnr correctly"), but that commit breaks highmem and needs to be reverted. We can't easily fix __pa(), we have code that relies on its current behaviour. So for now add extra checks to virt_addr_valid(). For 64-bit Book3S the extra checks are not necessary, the combination of virt_to_pfn() and pfn_valid() should yield the correct result, but they are harmless. [mpe: Add additional change log detail]
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a3727c25eacd7e437c4f560957fa3a376fe93e6bPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/cbc065efcba000ad8f615f506ebe61b6d3c5145bPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d36febbcd537fcc50284e8b89609632d0146529fPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/deab81144d5a043f42804207fb76cfbd8a806978Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fddb88bd266f4513abab7c36bca98935c9148a98Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ffa0b64e3be58519ae472ea29a1a1ad681e32f48Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 5.18
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/include/asm/page.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "deab81144d5a043f42804207fb76cfbd8a806978",
              "status": "affected",
              "version": "ffda09a9941c18d9f08d1176d55588d505f62912",
              "versionType": "git"
            },
            {
              "lessThan": "d36febbcd537fcc50284e8b89609632d0146529f",
              "status": "affected",
              "version": "ffda09a9941c18d9f08d1176d55588d505f62912",
              "versionType": "git"
            },
            {
              "lessThan": "fddb88bd266f4513abab7c36bca98935c9148a98",
              "status": "affected",
              "version": "ffda09a9941c18d9f08d1176d55588d505f62912",
              "versionType": "git"
            },
            {
              "lessThan": "a3727c25eacd7e437c4f560957fa3a376fe93e6b",
              "status": "affected",
              "version": "ffda09a9941c18d9f08d1176d55588d505f62912",
              "versionType": "git"
            },
            {
              "lessThan": "cbc065efcba000ad8f615f506ebe61b6d3c5145b",
              "status": "affected",
              "version": "ffda09a9941c18d9f08d1176d55588d505f62912",
              "versionType": "git"
            },
            {
              "lessThan": "ffa0b64e3be58519ae472ea29a1a1ad681e32f48",
              "status": "affected",
              "version": "ffda09a9941c18d9f08d1176d55588d505f62912",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/include/asm/page.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.4"
            },
            {
              "lessThan": "4.4",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.190",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.111",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.34",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.16.*",
              "status": "unaffected",
              "version": "5.16.20",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.17.*",
              "status": "unaffected",
              "version": "5.17.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "07007AB8-22EB-4618-8183-08F71279EB4E",
              "versionEndExcluding": "5.4.190",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "96258501-7BCE-4C55-8A38-8AC9D327626D",
              "versionEndExcluding": "5.10.111",
              "versionStartIncluding": "5.5",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D25878D3-7761-4E9F-8919-E92CD53896E0",
              "versionEndExcluding": "5.15.34",
              "versionStartIncluding": "5.11",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "ABBBA66E-0244-4621-966B-9790AF1EEB00",
              "versionEndExcluding": "5.16.20",
              "versionStartIncluding": "5.16",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "AE420AC7-1E59-4398-B84F-71F4B4337762",
              "versionEndExcluding": "5.17.3",
              "versionStartIncluding": "5.17",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "6AD94161-84BB-42E6-9882-4FC0C42E9FC1",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc: Fix virt_addr_valid() for 64-bit Book3E \u0026 32-bit\n\nmpe: On 64-bit Book3E vmalloc space starts at 0x8000000000000000.\n\nBecause of the way __pa() works we have:\n  __pa(0x8000000000000000) == 0, and therefore\n  virt_to_pfn(0x8000000000000000) == 0, and therefore\n  virt_addr_valid(0x8000000000000000) == true\n\nWhich is wrong, virt_addr_valid() should be false for vmalloc space.\nIn fact all vmalloc addresses that alias with a valid PFN will return\ntrue from virt_addr_valid(). That can cause bugs with hardened usercopy\nas described below by Kefeng Wang:\n\n  When running ethtool eth0 on 64-bit Book3E, a BUG occurred:\n\n    usercopy: Kernel memory exposure attempt detected from SLUB object not in SLUB page?! (offset 0, size 1048)!\n    kernel BUG at mm/usercopy.c:99\n    ...\n    usercopy_abort+0x64/0xa0 (unreliable)\n    __check_heap_object+0x168/0x190\n    __check_object_size+0x1a0/0x200\n    dev_ethtool+0x2494/0x2b20\n    dev_ioctl+0x5d0/0x770\n    sock_do_ioctl+0xf0/0x1d0\n    sock_ioctl+0x3ec/0x5a0\n    __se_sys_ioctl+0xf0/0x160\n    system_call_exception+0xfc/0x1f0\n    system_call_common+0xf8/0x200\n\n  The code shows below,\n\n    data = vzalloc(array_size(gstrings.len, ETH_GSTRING_LEN));\n    copy_to_user(useraddr, data, gstrings.len * ETH_GSTRING_LEN))\n\n  The data is alloced by vmalloc(), virt_addr_valid(ptr) will return true\n  on 64-bit Book3E, which leads to the panic.\n\n  As commit 4dd7554a6456 (\"powerpc/64: Add VIRTUAL_BUG_ON checks for __va\n  and __pa addresses\") does, make sure the virt addr above PAGE_OFFSET in\n  the virt_addr_valid() for 64-bit, also add upper limit check to make\n  sure the virt is below high_memory.\n\n  Meanwhile, for 32-bit PAGE_OFFSET is the virtual address of the start\n  of lowmem, high_memory is the upper low virtual address, the check is\n  suitable for 32-bit, this will fix the issue mentioned in commit\n  602946ec2f90 (\"powerpc: Set max_mapnr correctly\") too.\n\nOn 32-bit there is a similar problem with high memory, that was fixed in\ncommit 602946ec2f90 (\"powerpc: Set max_mapnr correctly\"), but that\ncommit breaks highmem and needs to be reverted.\n\nWe can\u0027t easily fix __pa(), we have code that relies on its current\nbehaviour. So for now add extra checks to virt_addr_valid().\n\nFor 64-bit Book3S the extra checks are not necessary, the combination of\nvirt_to_pfn() and pfn_valid() should yield the correct result, but they\nare harmless.\n\n[mpe: Add additional change log detail]"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: powerpc: Arreglar virt_addr_valid() para Book3E de 64 bits y mpe de 32 bits: En Book3E de 64 bits, el espacio vmalloc comienza en 0x8000000000000000. Debido a la forma en que funciona __pa() tenemos: __pa(0x8000000000000000) == 0, y por lo tanto virt_to_pfn(0x8000000000000000) == 0, y por lo tanto virt_addr_valid(0x8000000000000000) == true Lo cual es incorrecto, virt_addr_valid() deber\u00eda ser falso para el espacio vmalloc. De hecho, todas las direcciones vmalloc que tengan un alias con un PFN v\u00e1lido devolver\u00e1n verdadero desde virt_addr_valid(). Esto puede causar errores con usercopy reforzado como lo describe a continuaci\u00f3n Kefeng Wang: Al ejecutar ethtool eth0 en Book3E de 64 bits, ocurri\u00f3 un ERROR: usercopy: \u00a1Intento de exposici\u00f3n de memoria del kernel detectado desde un objeto SLUB que no est\u00e1 en la p\u00e1gina SLUB! (desplazamiento 0, tama\u00f1o 1048). ERROR del kernel en mm/usercopy.c:99 ... usercopy_abort+0x64/0xa0 (no confiable) __check_heap_object+0x168/0x190 __check_object_size+0x1a0/0x200 dev_ethtool+0x2494/0x2b20 dev_ioctl+0x5d0/0x770 sock_do_ioctl+0xf0/0x1d0 sock_ioctl+0x3ec/0x5a0 __se_sys_ioctl+0xf0/0x160 system_call_exception+0xfc/0x1f0 system_call_common+0xf8/0x200 El c\u00f3digo se muestra a continuaci\u00f3n, data = vzalloc(array_size(gstrings.len, ETH_GSTRING_LEN)); copy_to_user(useraddr, data, gstrings.len * ETH_GSTRING_LEN)) Los datos se asignan mediante vmalloc(), virt_addr_valid(ptr) devolver\u00e1 verdadero en Book3E de 64 bits, lo que genera el p\u00e1nico. Como lo hace el commit 4dd7554a6456 (\"powerpc/64: Agregar comprobaciones VIRTUAL_BUG_ON para direcciones __va y __pa\"), aseg\u00farese de que la direcci\u00f3n virt sea superior a PAGE_OFFSET en virt_addr_valid() para 64 bits, y agregue tambi\u00e9n una comprobaci\u00f3n de l\u00edmite superior para asegurarse de que la direcci\u00f3n virt est\u00e9 por debajo de high_memory. Mientras tanto, para 32 bits PAGE_OFFSET es la direcci\u00f3n virtual del inicio de lowmem, high_memory es la direcci\u00f3n virtual baja superior, la comprobaci\u00f3n es adecuada para 32 bits, esto solucionar\u00e1 tambi\u00e9n el problema mencionado en el commit 602946ec2f90 (\"powerpc: Set max_mapnr properly\"). En 32 bits hay un problema similar con la memoria alta, que se solucion\u00f3 en el commit 602946ec2f90 (\"powerpc: Set max_mapnr properly\"), pero ese commit rompe highmem y necesita ser revertido. No podemos arreglar f\u00e1cilmente __pa(), tenemos c\u00f3digo que depende de su comportamiento actual. As\u00ed que por ahora agregue comprobaciones adicionales a virt_addr_valid(). Para Book3S de 64 bits las comprobaciones adicionales no son necesarias, la combinaci\u00f3n de virt_to_pfn() y pfn_valid() deber\u00eda producir el resultado correcto, pero son inofensivas. [mpe: Agregar detalles adicionales del registro de cambios]"
    }
  ],
  "id": "CVE-2022-49067",
  "lastModified": "2026-06-17T05:16:59.383",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2025-02-26T07:00:43.927",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a3727c25eacd7e437c4f560957fa3a376fe93e6b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/cbc065efcba000ad8f615f506ebe61b6d3c5145b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/d36febbcd537fcc50284e8b89609632d0146529f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/deab81144d5a043f42804207fb76cfbd8a806978"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/fddb88bd266f4513abab7c36bca98935c9148a98"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/ffa0b64e3be58519ae472ea29a1a1ad681e32f48"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.


Detection rules are retrieved from Rulezet.


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.