{"api_version":"1","generated_at":"2026-05-11T14:59:20+00:00","cve":"CVE-2026-43288","urls":{"html":"https://cve.report/CVE-2026-43288","api":"https://cve.report/api/cve/CVE-2026-43288.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43288","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43288"},"summary":{"title":"ext4: move ext4_percpu_param_init() before ext4_mb_init()","description":"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 <TASK>\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->s_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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-08 14:16:35","updated_at":"2026-05-08 14:16:35"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/bf5b609524497c195f801cd5707252384aed8149","name":"https://git.kernel.org/stable/c/bf5b609524497c195f801cd5707252384aed8149","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0d5fcb063cdabb9aeaa8554b7fedad2092c4150e","name":"https://git.kernel.org/stable/c/0d5fcb063cdabb9aeaa8554b7fedad2092c4150e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/270564513489d98b721a1e4a10017978d5213bff","name":"https://git.kernel.org/stable/c/270564513489d98b721a1e4a10017978d5213bff","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/aec095f3cc6cf209effd93278ce35be27db81d73","name":"https://git.kernel.org/stable/c/aec095f3cc6cf209effd93278ce35be27db81d73","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9e9fb259bcddf459a0168f4a964e979e500a68a5","name":"https://git.kernel.org/stable/c/9e9fb259bcddf459a0168f4a964e979e500a68a5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43288","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43288","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 0d5fcb063cdabb9aeaa8554b7fedad2092c4150e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 9e9fb259bcddf459a0168f4a964e979e500a68a5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 bf5b609524497c195f801cd5707252384aed8149 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 aec095f3cc6cf209effd93278ce35be27db81d73 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 270564513489d98b721a1e4a10017978d5213bff git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.128 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.75 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.16 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.6 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"43288","cve":"CVE-2026-43288","epss":"0.000180000","percentile":"0.050330000","score_date":"2026-05-10","updated_at":"2026-05-11 00:14:41"},"legacy_qids":[]},"source_records":{"cve_program":{"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":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"9e9fb259bcddf459a0168f4a964e979e500a68a5","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"bf5b609524497c195f801cd5707252384aed8149","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"aec095f3cc6cf209effd93278ce35be27db81d73","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"270564513489d98b721a1e4a10017978d5213bff","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","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":[{"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","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.75","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.6","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","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 <TASK>\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->s_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":"2026-05-08T13:11:13.195Z","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":"2026-05-08T13:11:13.195Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-08 14:16:35","lastModifiedDate":"2026-05-08 14:16:35","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43288","Ordinal":"1","Title":"ext4: move ext4_percpu_param_init() before ext4_mb_init()","CVE":"CVE-2026-43288","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43288","Ordinal":"1","NoteData":"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 <TASK>\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->s_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.","Type":"Description","Title":"ext4: move ext4_percpu_param_init() before ext4_mb_init()"}]}}}