CVE-2021-47623 (GCVE-0-2021-47623)

Vulnerability from cvelistv5 – Published: 2024-07-16 11:29 – Updated: 2026-05-11 13:58
VLAI
Title
powerpc/fixmap: Fix VM debug warning on unmap
Summary
In the Linux kernel, the following vulnerability has been resolved: powerpc/fixmap: Fix VM debug warning on unmap Unmapping a fixmap entry is done by calling __set_fixmap() with FIXMAP_PAGE_CLEAR as flags. Today, powerpc __set_fixmap() calls map_kernel_page(). map_kernel_page() is not happy when called a second time for the same page. WARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8 CPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682 NIP: c0017cd4 LR: c00187f0 CTR: 00000010 REGS: e1011d50 TRAP: 0700 Not tainted (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty) MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42000208 XER: 00000000 GPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c GPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 GPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000 NIP [c0017cd4] set_pte_at+0xc/0x1e8 LR [c00187f0] map_kernel_page+0x9c/0x100 Call Trace: [e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable) [e1011e30] [c0165fec] __set_fixmap+0x30/0x44 [e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170 [e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0 [e1011e90] [c0c03634] do_one_initcall+0x80/0x178 [e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250 [e1011f20] [c0007e34] kernel_init+0x24/0x140 [e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64 Instruction dump: 7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010 4e800020 81250000 712a0001 41820008 <0fe00000> 9421ffe0 93e1001c 48000030 Implement unmap_kernel_page() which clears an existing pte.
Severity
No CVSS data available.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-09-10 16:59 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 , < 67baac10dd5ad1e9f50e8f2659984b3b0728d54e (git)
Affected: 265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 , < 43ae0ccc4d2722b833fb59b905af129428e06d03 (git)
Affected: 265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 , < 033fd42c18d9b2121595b6f1e8419a115f9ac5b7 (git)
Affected: 265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 , < aec982603aa8cc0a21143681feb5f60ecc69d718 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.5
Unaffected: 0 , < 5.5 (semver)
Unaffected: 5.10.101 , ≤ 5.10.* (semver)
Unaffected: 5.15.24 , ≤ 5.15.* (semver)
Unaffected: 5.16.10 , ≤ 5.16.* (semver)
Unaffected: 5.17 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T05:47:40.568Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/67baac10dd5ad1e9f50e8f2659984b3b0728d54e"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/43ae0ccc4d2722b833fb59b905af129428e06d03"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/033fd42c18d9b2121595b6f1e8419a115f9ac5b7"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/aec982603aa8cc0a21143681feb5f60ecc69d718"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47623",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-09-10T16:59:58.410712Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-09-11T17:33:00.491Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/include/asm/book3s/32/pgtable.h",
            "arch/powerpc/include/asm/book3s/64/pgtable.h",
            "arch/powerpc/include/asm/fixmap.h",
            "arch/powerpc/include/asm/nohash/32/pgtable.h",
            "arch/powerpc/include/asm/nohash/64/pgtable.h",
            "arch/powerpc/mm/pgtable.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "67baac10dd5ad1e9f50e8f2659984b3b0728d54e",
              "status": "affected",
              "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
              "versionType": "git"
            },
            {
              "lessThan": "43ae0ccc4d2722b833fb59b905af129428e06d03",
              "status": "affected",
              "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
              "versionType": "git"
            },
            {
              "lessThan": "033fd42c18d9b2121595b6f1e8419a115f9ac5b7",
              "status": "affected",
              "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
              "versionType": "git"
            },
            {
              "lessThan": "aec982603aa8cc0a21143681feb5f60ecc69d718",
              "status": "affected",
              "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/powerpc/include/asm/book3s/32/pgtable.h",
            "arch/powerpc/include/asm/book3s/64/pgtable.h",
            "arch/powerpc/include/asm/fixmap.h",
            "arch/powerpc/include/asm/nohash/32/pgtable.h",
            "arch/powerpc/include/asm/nohash/64/pgtable.h",
            "arch/powerpc/mm/pgtable.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.5"
            },
            {
              "lessThan": "5.5",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.24",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.16.*",
              "status": "unaffected",
              "version": "5.16.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.17",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.101",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.24",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.16.10",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.17",
                  "versionStartIncluding": "5.5",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/fixmap: Fix VM debug warning on unmap\n\nUnmapping a fixmap entry is done by calling __set_fixmap()\nwith FIXMAP_PAGE_CLEAR as flags.\n\nToday, powerpc __set_fixmap() calls map_kernel_page().\n\nmap_kernel_page() is not happy when called a second time\nfor the same page.\n\n\tWARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8\n\tCPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682\n\tNIP:  c0017cd4 LR: c00187f0 CTR: 00000010\n\tREGS: e1011d50 TRAP: 0700   Not tainted  (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty)\n\tMSR:  00029032 \u003cEE,ME,IR,DR,RI\u003e  CR: 42000208  XER: 00000000\n\n\tGPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c\n\tGPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000\n\tGPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000\n\tGPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000\n\tNIP [c0017cd4] set_pte_at+0xc/0x1e8\n\tLR [c00187f0] map_kernel_page+0x9c/0x100\n\tCall Trace:\n\t[e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable)\n\t[e1011e30] [c0165fec] __set_fixmap+0x30/0x44\n\t[e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170\n\t[e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0\n\t[e1011e90] [c0c03634] do_one_initcall+0x80/0x178\n\t[e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250\n\t[e1011f20] [c0007e34] kernel_init+0x24/0x140\n\t[e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64\n\tInstruction dump:\n\t7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010\n\t4e800020 81250000 712a0001 41820008 \u003c0fe00000\u003e 9421ffe0 93e1001c 48000030\n\nImplement unmap_kernel_page() which clears an existing pte."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T13:58:05.571Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/67baac10dd5ad1e9f50e8f2659984b3b0728d54e"
        },
        {
          "url": "https://git.kernel.org/stable/c/43ae0ccc4d2722b833fb59b905af129428e06d03"
        },
        {
          "url": "https://git.kernel.org/stable/c/033fd42c18d9b2121595b6f1e8419a115f9ac5b7"
        },
        {
          "url": "https://git.kernel.org/stable/c/aec982603aa8cc0a21143681feb5f60ecc69d718"
        }
      ],
      "title": "powerpc/fixmap: Fix VM debug warning on unmap",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-47623",
    "datePublished": "2024-07-16T11:29:39.071Z",
    "dateReserved": "2024-07-16T11:26:52.956Z",
    "dateUpdated": "2026-05-11T13:58:05.571Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2021-47623",
      "date": "2026-09-24",
      "epss": "0.00225",
      "percentile": "0.11737"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "arch/powerpc/include/asm/book3s/32/pgtable.h",
                  "arch/powerpc/include/asm/book3s/64/pgtable.h",
                  "arch/powerpc/include/asm/fixmap.h",
                  "arch/powerpc/include/asm/nohash/32/pgtable.h",
                  "arch/powerpc/include/asm/nohash/64/pgtable.h",
                  "arch/powerpc/mm/pgtable.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "67baac10dd5ad1e9f50e8f2659984b3b0728d54e",
                    "status": "affected",
                    "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "43ae0ccc4d2722b833fb59b905af129428e06d03",
                    "status": "affected",
                    "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "033fd42c18d9b2121595b6f1e8419a115f9ac5b7",
                    "status": "affected",
                    "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "aec982603aa8cc0a21143681feb5f60ecc69d718",
                    "status": "affected",
                    "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "arch/powerpc/include/asm/book3s/32/pgtable.h",
                  "arch/powerpc/include/asm/book3s/64/pgtable.h",
                  "arch/powerpc/include/asm/fixmap.h",
                  "arch/powerpc/include/asm/nohash/32/pgtable.h",
                  "arch/powerpc/include/asm/nohash/64/pgtable.h",
                  "arch/powerpc/mm/pgtable.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "5.5"
                  },
                  {
                    "lessThan": "5.5",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.101",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.24",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.16.*",
                    "status": "unaffected",
                    "version": "5.16.10",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "5.17",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "F37E3FA0-7A8B-4AAF-9748-96E34396B25B",
                    "versionEndExcluding": "5.10.101",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "866451F0-299E-416C-B0B8-AE6B33E62CCA",
                    "versionEndExcluding": "5.15.24",
                    "versionStartIncluding": "5.11",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "679523BA-1392-404B-AB85-F5A5408B1ECC",
                    "versionEndExcluding": "5.16.10",
                    "versionStartIncluding": "5.16",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:5.17:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "7BD5F8D9-54FA-4CB0-B4F0-CB0471FDDB2D",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/fixmap: Fix VM debug warning on unmap\n\nUnmapping a fixmap entry is done by calling __set_fixmap()\nwith FIXMAP_PAGE_CLEAR as flags.\n\nToday, powerpc __set_fixmap() calls map_kernel_page().\n\nmap_kernel_page() is not happy when called a second time\nfor the same page.\n\n\tWARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8\n\tCPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682\n\tNIP:  c0017cd4 LR: c00187f0 CTR: 00000010\n\tREGS: e1011d50 TRAP: 0700   Not tainted  (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty)\n\tMSR:  00029032 \u003cEE,ME,IR,DR,RI\u003e  CR: 42000208  XER: 00000000\n\n\tGPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c\n\tGPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000\n\tGPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000\n\tGPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000\n\tNIP [c0017cd4] set_pte_at+0xc/0x1e8\n\tLR [c00187f0] map_kernel_page+0x9c/0x100\n\tCall Trace:\n\t[e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable)\n\t[e1011e30] [c0165fec] __set_fixmap+0x30/0x44\n\t[e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170\n\t[e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0\n\t[e1011e90] [c0c03634] do_one_initcall+0x80/0x178\n\t[e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250\n\t[e1011f20] [c0007e34] kernel_init+0x24/0x140\n\t[e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64\n\tInstruction dump:\n\t7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010\n\t4e800020 81250000 712a0001 41820008 \u003c0fe00000\u003e 9421ffe0 93e1001c 48000030\n\nImplement unmap_kernel_page() which clears an existing pte."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: powerpc/fixmap: corrige la advertencia de depuraci\u00f3n de VM al desasignar La desasignaci\u00f3n de una entrada de fixmap se realiza llamando a __set_fixmap() con FIXMAP_PAGE_CLEAR como indicadores. Hoy, powerpc __set_fixmap() llama a map_kernel_page(). map_kernel_page() no est\u00e1 contento cuando se le llama por segunda vez para la misma p\u00e1gina. ADVERTENCIA: CPU: 0 PID: 1 en arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8 CPU: 0 PID: 1 Comm: swapper No contaminado 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d- sucio #682 NIP: c0017cd4 LR: c00187f0 CTR: 00000010 REGS: e1011d50 TRAP: 0700 No contaminado (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty) MSR: 00029032  CR: 42000208 XER: 00000000 GPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c GPR08: 00001000 b00045a9 00000001 c 0f58460 c0f50000 00000000 c0007e10 00000000 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 GPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000 PIN [c0017cd4 ] set_pte_at+0xc/0x1e8 LR [c00187f0] map_kernel_page+0x9c/0x100 Seguimiento de llamadas: [e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (no confiable) [e1011e30] [c0165fec] x44 [e1011e40] [c0c13bdc] early_iounmap +0x11c/0x170 [e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0 [e1011e90] [c0c03634] do_one_initcall+0x80/0x178 [e1011ef0] [c0c0385c] kernel_init_freeable+0xb4 /0x250 [e1011f20] [c0007e34] kernel_init+0x24/0x140 [e1011f30 ] [c0016268] ret_from_kernel_thread+0x5c/0x64 Volcado de instrucciones: 7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010 4e800020 0 712a0001 41820008 \u0026lt;0fe00000\u0026gt; 9421ffe0 93e1001c 48000030 Implemente unmap_kernel_page() que borra un pte existente."
          }
        ],
        "id": "CVE-2021-47623",
        "lastModified": "2026-06-17T04:18:11.293",
        "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"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2021-47623",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-09-10T16:59:58.410712Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2024-07-16T12:15:02.483",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/033fd42c18d9b2121595b6f1e8419a115f9ac5b7"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/43ae0ccc4d2722b833fb59b905af129428e06d03"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/67baac10dd5ad1e9f50e8f2659984b3b0728d54e"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/aec982603aa8cc0a21143681feb5f60ecc69d718"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/033fd42c18d9b2121595b6f1e8419a115f9ac5b7"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/43ae0ccc4d2722b833fb59b905af129428e06d03"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/67baac10dd5ad1e9f50e8f2659984b3b0728d54e"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/aec982603aa8cc0a21143681feb5f60ecc69d718"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "NVD-CWE-noinfo"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2025-11-21T10:45:44+00:00",
      "cve": "CVE-2021-47623",
      "id": "CVE-2021-47623",
      "initial_release_date": "2021-01-01T00:00:00+00:00",
      "product_status:fixed": "210",
      "product_status:known_affected": "198",
      "product_status:known_not_affected": "8",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: powerpc/fixmap: Fix VM debug warning on unmap",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-47623.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2024-08-04T05:47:40.568Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
            },
            "references": [
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/67baac10dd5ad1e9f50e8f2659984b3b0728d54e"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/43ae0ccc4d2722b833fb59b905af129428e06d03"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/033fd42c18d9b2121595b6f1e8419a115f9ac5b7"
              },
              {
                "tags": [
                  "x_transferred"
                ],
                "url": "https://git.kernel.org/stable/c/aec982603aa8cc0a21143681feb5f60ecc69d718"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2021-47623",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2024-09-10T16:59:58.410712Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2024-09-11T12:42:14.030Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Linux",
              "programFiles": [
                "arch/powerpc/include/asm/book3s/32/pgtable.h",
                "arch/powerpc/include/asm/book3s/64/pgtable.h",
                "arch/powerpc/include/asm/fixmap.h",
                "arch/powerpc/include/asm/nohash/32/pgtable.h",
                "arch/powerpc/include/asm/nohash/64/pgtable.h",
                "arch/powerpc/mm/pgtable.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "lessThan": "67baac10dd5ad1e9f50e8f2659984b3b0728d54e",
                  "status": "affected",
                  "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                  "versionType": "git"
                },
                {
                  "lessThan": "43ae0ccc4d2722b833fb59b905af129428e06d03",
                  "status": "affected",
                  "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                  "versionType": "git"
                },
                {
                  "lessThan": "033fd42c18d9b2121595b6f1e8419a115f9ac5b7",
                  "status": "affected",
                  "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                  "versionType": "git"
                },
                {
                  "lessThan": "aec982603aa8cc0a21143681feb5f60ecc69d718",
                  "status": "affected",
                  "version": "265c3491c4bc8d40587996d6ee2f447a7ccfb4f3",
                  "versionType": "git"
                }
              ]
            },
            {
              "defaultStatus": "affected",
              "product": "Linux",
              "programFiles": [
                "arch/powerpc/include/asm/book3s/32/pgtable.h",
                "arch/powerpc/include/asm/book3s/64/pgtable.h",
                "arch/powerpc/include/asm/fixmap.h",
                "arch/powerpc/include/asm/nohash/32/pgtable.h",
                "arch/powerpc/include/asm/nohash/64/pgtable.h",
                "arch/powerpc/mm/pgtable.c"
              ],
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "vendor": "Linux",
              "versions": [
                {
                  "status": "affected",
                  "version": "5.5"
                },
                {
                  "lessThan": "5.5",
                  "status": "unaffected",
                  "version": "0",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.10.*",
                  "status": "unaffected",
                  "version": "5.10.101",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.15.*",
                  "status": "unaffected",
                  "version": "5.15.24",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "5.16.*",
                  "status": "unaffected",
                  "version": "5.16.10",
                  "versionType": "semver"
                },
                {
                  "lessThanOrEqual": "*",
                  "status": "unaffected",
                  "version": "5.17",
                  "versionType": "original_commit_for_fix"
                }
              ]
            }
          ],
          "cpeApplicability": [
            {
              "nodes": [
                {
                  "cpeMatch": [
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.10.101",
                      "versionStartIncluding": "5.5",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.15.24",
                      "versionStartIncluding": "5.5",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.16.10",
                      "versionStartIncluding": "5.5",
                      "vulnerable": true
                    },
                    {
                      "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                      "versionEndExcluding": "5.17",
                      "versionStartIncluding": "5.5",
                      "vulnerable": true
                    }
                  ],
                  "negate": false,
                  "operator": "OR"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/fixmap: Fix VM debug warning on unmap\n\nUnmapping a fixmap entry is done by calling __set_fixmap()\nwith FIXMAP_PAGE_CLEAR as flags.\n\nToday, powerpc __set_fixmap() calls map_kernel_page().\n\nmap_kernel_page() is not happy when called a second time\nfor the same page.\n\n\tWARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8\n\tCPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682\n\tNIP:  c0017cd4 LR: c00187f0 CTR: 00000010\n\tREGS: e1011d50 TRAP: 0700   Not tainted  (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty)\n\tMSR:  00029032 \u003cEE,ME,IR,DR,RI\u003e  CR: 42000208  XER: 00000000\n\n\tGPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c\n\tGPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000\n\tGPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000\n\tGPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000\n\tNIP [c0017cd4] set_pte_at+0xc/0x1e8\n\tLR [c00187f0] map_kernel_page+0x9c/0x100\n\tCall Trace:\n\t[e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable)\n\t[e1011e30] [c0165fec] __set_fixmap+0x30/0x44\n\t[e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170\n\t[e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0\n\t[e1011e90] [c0c03634] do_one_initcall+0x80/0x178\n\t[e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250\n\t[e1011f20] [c0007e34] kernel_init+0x24/0x140\n\t[e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64\n\tInstruction dump:\n\t7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010\n\t4e800020 81250000 712a0001 41820008 \u003c0fe00000\u003e 9421ffe0 93e1001c 48000030\n\nImplement unmap_kernel_page() which clears an existing pte."
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2025-12-09T21:44:17.581Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/67baac10dd5ad1e9f50e8f2659984b3b0728d54e"
            },
            {
              "url": "https://git.kernel.org/stable/c/43ae0ccc4d2722b833fb59b905af129428e06d03"
            },
            {
              "url": "https://git.kernel.org/stable/c/033fd42c18d9b2121595b6f1e8419a115f9ac5b7"
            },
            {
              "url": "https://git.kernel.org/stable/c/aec982603aa8cc0a21143681feb5f60ecc69d718"
            }
          ],
          "title": "powerpc/fixmap: Fix VM debug warning on unmap",
          "x_generator": {
            "engine": "bippy-1.2.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2021-47623",
        "datePublished": "2024-07-16T11:29:39.071Z",
        "dateReserved": "2024-07-16T11:26:52.956Z",
        "dateUpdated": "2025-12-09T21:44:17.581Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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.



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.