CVE-2026-43288 (GCVE-0-2026-43288)

Vulnerability from cvelistv5 – Published: 2026-05-08 13:11 – Updated: 2026-05-11 22:21
VLAI
Title
ext4: move ext4_percpu_param_init() before ext4_mb_init()
Summary
In the Linux kernel, the following vulnerability has been resolved: ext4: move ext4_percpu_param_init() before ext4_mb_init() When running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the `DOUBLE_CHECK` macro defined, the following panic is triggered: ================================================================== EXT4-fs error (device vdc): ext4_validate_block_bitmap:423: comm mount: bg 0: bad block bitmap checksum BUG: unable to handle page fault for address: ff110000fa2cc000 PGD 3e01067 P4D 3e02067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 Call Trace: <TASK> ext4_mark_group_bitmap_corrupted+0xcb/0xe0 ext4_validate_block_bitmap+0x2a1/0x2f0 ext4_read_block_bitmap+0x33/0x50 mb_group_bb_bitmap_alloc+0x33/0x80 ext4_mb_add_groupinfo+0x190/0x250 ext4_mb_init_backend+0x87/0x290 ext4_mb_init+0x456/0x640 __ext4_fill_super+0x1072/0x1680 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4f6/0x6b0 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== This issue can be reproduced using the following commands: mkfs.ext4 -F -q -b 1024 /dev/sda 5G tune2fs -O quota,project /dev/sda mount /dev/sda /tmp/test With DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads and validates the block bitmap. When the validation fails, ext4_mark_group_bitmap_corrupted() attempts to update sbi->s_freeclusters_counter. However, this percpu_counter has not been initialized yet at this point, which leads to the panic described above. Fix this by moving the execution of ext4_percpu_param_init() to occur before ext4_mb_init(), ensuring the per-CPU counters are initialized before they are used.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: d5e03cbb0c88cd1be39f2adc37d602230045964b , < 0d5fcb063cdabb9aeaa8554b7fedad2092c4150e (git)
Affected: d5e03cbb0c88cd1be39f2adc37d602230045964b , < 9e9fb259bcddf459a0168f4a964e979e500a68a5 (git)
Affected: d5e03cbb0c88cd1be39f2adc37d602230045964b , < bf5b609524497c195f801cd5707252384aed8149 (git)
Affected: d5e03cbb0c88cd1be39f2adc37d602230045964b , < aec095f3cc6cf209effd93278ce35be27db81d73 (git)
Affected: d5e03cbb0c88cd1be39f2adc37d602230045964b , < 270564513489d98b721a1e4a10017978d5213bff (git)
Create a notification for this product.
Linux Linux Affected: 3.17
Unaffected: 0 , < 3.17 (semver)
Unaffected: 6.6.128 , ≤ 6.6.* (semver)
Unaffected: 6.12.75 , ≤ 6.12.* (semver)
Unaffected: 6.18.16 , ≤ 6.18.* (semver)
Unaffected: 6.19.6 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ext4/super.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0d5fcb063cdabb9aeaa8554b7fedad2092c4150e",
              "status": "affected",
              "version": "d5e03cbb0c88cd1be39f2adc37d602230045964b",
              "versionType": "git"
            },
            {
              "lessThan": "9e9fb259bcddf459a0168f4a964e979e500a68a5",
              "status": "affected",
              "version": "d5e03cbb0c88cd1be39f2adc37d602230045964b",
              "versionType": "git"
            },
            {
              "lessThan": "bf5b609524497c195f801cd5707252384aed8149",
              "status": "affected",
              "version": "d5e03cbb0c88cd1be39f2adc37d602230045964b",
              "versionType": "git"
            },
            {
              "lessThan": "aec095f3cc6cf209effd93278ce35be27db81d73",
              "status": "affected",
              "version": "d5e03cbb0c88cd1be39f2adc37d602230045964b",
              "versionType": "git"
            },
            {
              "lessThan": "270564513489d98b721a1e4a10017978d5213bff",
              "status": "affected",
              "version": "d5e03cbb0c88cd1be39f2adc37d602230045964b",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ext4/super.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.17"
            },
            {
              "lessThan": "3.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.128",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.75",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.128",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.75",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.16",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.6",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: move ext4_percpu_param_init() before ext4_mb_init()\n\nWhen running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the\n`DOUBLE_CHECK` macro defined, the following panic is triggered:\n\n==================================================================\nEXT4-fs error (device vdc): ext4_validate_block_bitmap:423:\n                        comm mount: bg 0: bad block bitmap checksum\nBUG: unable to handle page fault for address: ff110000fa2cc000\nPGD 3e01067 P4D 3e02067 PUD 0\nOops: Oops: 0000 [#1] SMP NOPTI\nCPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W\n                        6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none)\nRIP: 0010:percpu_counter_add_batch+0x13/0xa0\nCall Trace:\n \u003cTASK\u003e\n ext4_mark_group_bitmap_corrupted+0xcb/0xe0\n ext4_validate_block_bitmap+0x2a1/0x2f0\n ext4_read_block_bitmap+0x33/0x50\n mb_group_bb_bitmap_alloc+0x33/0x80\n ext4_mb_add_groupinfo+0x190/0x250\n ext4_mb_init_backend+0x87/0x290\n ext4_mb_init+0x456/0x640\n __ext4_fill_super+0x1072/0x1680\n ext4_fill_super+0xd3/0x280\n get_tree_bdev_flags+0x132/0x1d0\n vfs_get_tree+0x29/0xd0\n vfs_cmd_create+0x59/0xe0\n __do_sys_fsconfig+0x4f6/0x6b0\n do_syscall_64+0x50/0x1f0\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n==================================================================\n\nThis issue can be reproduced using the following commands:\n        mkfs.ext4 -F -q -b 1024 /dev/sda 5G\n        tune2fs -O quota,project /dev/sda\n        mount /dev/sda /tmp/test\n\nWith DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads\nand validates the block bitmap. When the validation fails,\next4_mark_group_bitmap_corrupted() attempts to update\nsbi-\u003es_freeclusters_counter. However, this percpu_counter has not been\ninitialized yet at this point, which leads to the panic described above.\n\nFix this by moving the execution of ext4_percpu_param_init() to occur\nbefore ext4_mb_init(), ensuring the per-CPU counters are initialized\nbefore they are used."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T22:21:39.536Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/0d5fcb063cdabb9aeaa8554b7fedad2092c4150e"
        },
        {
          "url": "https://git.kernel.org/stable/c/9e9fb259bcddf459a0168f4a964e979e500a68a5"
        },
        {
          "url": "https://git.kernel.org/stable/c/bf5b609524497c195f801cd5707252384aed8149"
        },
        {
          "url": "https://git.kernel.org/stable/c/aec095f3cc6cf209effd93278ce35be27db81d73"
        },
        {
          "url": "https://git.kernel.org/stable/c/270564513489d98b721a1e4a10017978d5213bff"
        }
      ],
      "title": "ext4: move ext4_percpu_param_init() before ext4_mb_init()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43288",
    "datePublished": "2026-05-08T13:11:13.195Z",
    "dateReserved": "2026-05-01T14:12:55.999Z",
    "dateUpdated": "2026-05-11T22:21:39.536Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-43288",
      "date": "2026-07-05",
      "epss": "0.0013",
      "percentile": "0.02937"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-43288\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-05-08T14:16:35.737\",\"lastModified\":\"2026-06-17T10:49:19.040\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\next4: move ext4_percpu_param_init() before ext4_mb_init()\\n\\nWhen running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the\\n`DOUBLE_CHECK` macro defined, the following panic is triggered:\\n\\n==================================================================\\nEXT4-fs error (device vdc): ext4_validate_block_bitmap:423:\\n                        comm mount: bg 0: bad block bitmap checksum\\nBUG: unable to handle page fault for address: ff110000fa2cc000\\nPGD 3e01067 P4D 3e02067 PUD 0\\nOops: Oops: 0000 [#1] SMP NOPTI\\nCPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W\\n                        6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none)\\nRIP: 0010:percpu_counter_add_batch+0x13/0xa0\\nCall Trace:\\n \u003cTASK\u003e\\n ext4_mark_group_bitmap_corrupted+0xcb/0xe0\\n ext4_validate_block_bitmap+0x2a1/0x2f0\\n ext4_read_block_bitmap+0x33/0x50\\n mb_group_bb_bitmap_alloc+0x33/0x80\\n ext4_mb_add_groupinfo+0x190/0x250\\n ext4_mb_init_backend+0x87/0x290\\n ext4_mb_init+0x456/0x640\\n __ext4_fill_super+0x1072/0x1680\\n ext4_fill_super+0xd3/0x280\\n get_tree_bdev_flags+0x132/0x1d0\\n vfs_get_tree+0x29/0xd0\\n vfs_cmd_create+0x59/0xe0\\n __do_sys_fsconfig+0x4f6/0x6b0\\n do_syscall_64+0x50/0x1f0\\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\\n==================================================================\\n\\nThis issue can be reproduced using the following commands:\\n        mkfs.ext4 -F -q -b 1024 /dev/sda 5G\\n        tune2fs -O quota,project /dev/sda\\n        mount /dev/sda /tmp/test\\n\\nWith DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads\\nand validates the block bitmap. When the validation fails,\\next4_mark_group_bitmap_corrupted() attempts to update\\nsbi-\u003es_freeclusters_counter. However, this percpu_counter has not been\\ninitialized yet at this point, which leads to the panic described above.\\n\\nFix this by moving the execution of ext4_percpu_param_init() to occur\\nbefore ext4_mb_init(), ensuring the per-CPU counters are initialized\\nbefore they are used.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/ext4/super.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"d5e03cbb0c88cd1be39f2adc37d602230045964b\",\"lessThan\":\"0d5fcb063cdabb9aeaa8554b7fedad2092c4150e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d5e03cbb0c88cd1be39f2adc37d602230045964b\",\"lessThan\":\"9e9fb259bcddf459a0168f4a964e979e500a68a5\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d5e03cbb0c88cd1be39f2adc37d602230045964b\",\"lessThan\":\"bf5b609524497c195f801cd5707252384aed8149\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d5e03cbb0c88cd1be39f2adc37d602230045964b\",\"lessThan\":\"aec095f3cc6cf209effd93278ce35be27db81d73\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d5e03cbb0c88cd1be39f2adc37d602230045964b\",\"lessThan\":\"270564513489d98b721a1e4a10017978d5213bff\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/ext4/super.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3.17\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"3.17\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.128\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.75\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.16\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.19.6\",\"lessThanOrEqual\":\"6.19.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.0\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":5.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-908\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"3.17\",\"versionEndExcluding\":\"6.6.128\",\"matchCriteriaId\":\"A1706372-54DA-4071-B3F0-1DF561FE84E8\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.12.75\",\"matchCriteriaId\":\"BCE16369-98ED-41CF-8995-DFDC10B288D2\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.13\",\"versionEndExcluding\":\"6.18.16\",\"matchCriteriaId\":\"B4B8CDA9-BADF-4CF5-8B3B-702DE8EEA40B\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.19\",\"versionEndExcluding\":\"6.19.6\",\"matchCriteriaId\":\"373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"F253B622-8837-4245-BCE5-A7BF8FC76A16\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"F666C8D8-6538-46D4-B318-87610DE64C34\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"02259FDA-961B-47BC-AE7F-93D7EC6E90C2\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*\",\"matchCriteriaId\":\"58A9FEFF-C040-420D-8F0A-BFDAAA1DF258\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*\",\"matchCriteriaId\":\"1D2315C0-D46F-4F85-9754-F9E5E11374A6\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*\",\"matchCriteriaId\":\"512EE3A8-A590-4501-9A94-5D4B268D6138\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0d5fcb063cdabb9aeaa8554b7fedad2092c4150e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/270564513489d98b721a1e4a10017978d5213bff\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/9e9fb259bcddf459a0168f4a964e979e500a68a5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/aec095f3cc6cf209effd93278ce35be27db81d73\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/bf5b609524497c195f801cd5707252384aed8149\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]}]}}"
  }
}


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.