{"api_version":"1","generated_at":"2026-06-03T09:30:24+00:00","cve":"CVE-2026-45985","urls":{"html":"https://cve.report/CVE-2026-45985","api":"https://cve.report/api/cve/CVE-2026-45985.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-45985","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-45985"},"summary":{"title":"ext4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before submitting I/O","description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before submitting I/O\n\nWhen allocating blocks during within-EOF DIO and writeback with\ndioread_nolock enabled, EXT4_GET_BLOCKS_PRE_IO was set to split an\nexisting large unwritten extent. However, EXT4_GET_BLOCKS_CONVERT was\nset when calling ext4_split_convert_extents(), which may potentially\nresult in stale data issues.\n\nAssume we have an unwritten extent, and then DIO writes the second half.\n\n   [UUUUUUUUUUUUUUUU] on-disk extent        U: unwritten extent\n   [UUUUUUUUUUUUUUUU] extent status tree\n            |<-   ->| ----> dio write this range\n\nFirst, ext4_iomap_alloc() call ext4_map_blocks() with\nEXT4_GET_BLOCKS_PRE_IO, EXT4_GET_BLOCKS_UNWRIT_EXT and\nEXT4_GET_BLOCKS_CREATE flags set. ext4_map_blocks() find this extent and\ncall ext4_split_convert_extents() with EXT4_GET_BLOCKS_CONVERT and the\nabove flags set.\n\nThen, ext4_split_convert_extents() calls ext4_split_extent() with\nEXT4_EXT_MAY_ZEROOUT, EXT4_EXT_MARK_UNWRIT2 and EXT4_EXT_DATA_VALID2\nflags set, and it calls ext4_split_extent_at() to split the second half\nwith EXT4_EXT_DATA_VALID2, EXT4_EXT_MARK_UNWRIT1, EXT4_EXT_MAY_ZEROOUT\nand EXT4_EXT_MARK_UNWRIT2 flags set. However, ext4_split_extent_at()\nfailed to insert extent since a temporary lack -ENOSPC. It zeroes out\nthe first half but convert the entire on-disk extent to written since\nthe EXT4_EXT_DATA_VALID2 flag set, but left the second half as unwritten\nin the extent status tree.\n\n   [0000000000SSSSSS]  data                S: stale data, 0: zeroed\n   [WWWWWWWWWWWWWWWW]  on-disk extent      W: written extent\n   [WWWWWWWWWWUUUUUU]  extent status tree\n\nFinally, if the DIO failed to write data to the disk, the stale data in\nthe second half will be exposed once the cached extent entry is gone.\n\nFix this issue by not passing EXT4_GET_BLOCKS_CONVERT when splitting\nan unwritten extent before submitting I/O, and make\next4_split_convert_extents() to zero out the entire extent range\nto zero for this case, and also mark the extent in the extent status\ntree for consistency.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-27 14:17:15","updated_at":"2026-05-27 14:48:03"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/2920ec61c98b9476781359f05b94da84e80f54d4","name":"https://git.kernel.org/stable/c/2920ec61c98b9476781359f05b94da84e80f54d4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2698731d25823267c29190cb578da9296a0c0d7b","name":"https://git.kernel.org/stable/c/2698731d25823267c29190cb578da9296a0c0d7b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/77e407967cd872cd75d7e4a691908e49c8e6b4d4","name":"https://git.kernel.org/stable/c/77e407967cd872cd75d7e4a691908e49c8e6b4d4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/716e7439a5a9b18c3ff882c2f8c834b9ced1aaec","name":"https://git.kernel.org/stable/c/716e7439a5a9b18c3ff882c2f8c834b9ced1aaec","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/37555690f39f78ef69af347d9aff897e07445949","name":"https://git.kernel.org/stable/c/37555690f39f78ef69af347d9aff897e07445949","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/67cdb7bd7442bd3cdc6d6088bbb2df9be2fe936c","name":"https://git.kernel.org/stable/c/67cdb7bd7442bd3cdc6d6088bbb2df9be2fe936c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/feaf2a80e78f89ee8a3464126077ba8683b62791","name":"https://git.kernel.org/stable/c/feaf2a80e78f89ee8a3464126077ba8683b62791","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-45985","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45985","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b8a8684502a0fc852afa0056c6bb2a9273f6fcc0 77e407967cd872cd75d7e4a691908e49c8e6b4d4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b8a8684502a0fc852afa0056c6bb2a9273f6fcc0 37555690f39f78ef69af347d9aff897e07445949 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b8a8684502a0fc852afa0056c6bb2a9273f6fcc0 67cdb7bd7442bd3cdc6d6088bbb2df9be2fe936c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b8a8684502a0fc852afa0056c6bb2a9273f6fcc0 2920ec61c98b9476781359f05b94da84e80f54d4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b8a8684502a0fc852afa0056c6bb2a9273f6fcc0 2698731d25823267c29190cb578da9296a0c0d7b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b8a8684502a0fc852afa0056c6bb2a9273f6fcc0 716e7439a5a9b18c3ff882c2f8c834b9ced1aaec git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b8a8684502a0fc852afa0056c6bb2a9273f6fcc0 feaf2a80e78f89ee8a3464126077ba8683b62791 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3.15","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 3.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.253 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.203 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.130 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.77 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.17 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.4 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":"45985","cve":"CVE-2026-45985","epss":"0.000240000","percentile":"0.073320000","score_date":"2026-06-01","updated_at":"2026-06-02 00:05:21"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/ext4/extents.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"77e407967cd872cd75d7e4a691908e49c8e6b4d4","status":"affected","version":"b8a8684502a0fc852afa0056c6bb2a9273f6fcc0","versionType":"git"},{"lessThan":"37555690f39f78ef69af347d9aff897e07445949","status":"affected","version":"b8a8684502a0fc852afa0056c6bb2a9273f6fcc0","versionType":"git"},{"lessThan":"67cdb7bd7442bd3cdc6d6088bbb2df9be2fe936c","status":"affected","version":"b8a8684502a0fc852afa0056c6bb2a9273f6fcc0","versionType":"git"},{"lessThan":"2920ec61c98b9476781359f05b94da84e80f54d4","status":"affected","version":"b8a8684502a0fc852afa0056c6bb2a9273f6fcc0","versionType":"git"},{"lessThan":"2698731d25823267c29190cb578da9296a0c0d7b","status":"affected","version":"b8a8684502a0fc852afa0056c6bb2a9273f6fcc0","versionType":"git"},{"lessThan":"716e7439a5a9b18c3ff882c2f8c834b9ced1aaec","status":"affected","version":"b8a8684502a0fc852afa0056c6bb2a9273f6fcc0","versionType":"git"},{"lessThan":"feaf2a80e78f89ee8a3464126077ba8683b62791","status":"affected","version":"b8a8684502a0fc852afa0056c6bb2a9273f6fcc0","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/ext4/extents.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"3.15"},{"lessThan":"3.15","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.253","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.203","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.130","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.77","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.17","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.4","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":"5.10.253","versionStartIncluding":"3.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.203","versionStartIncluding":"3.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.130","versionStartIncluding":"3.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.77","versionStartIncluding":"3.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.17","versionStartIncluding":"3.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.4","versionStartIncluding":"3.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"3.15","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before submitting I/O\n\nWhen allocating blocks during within-EOF DIO and writeback with\ndioread_nolock enabled, EXT4_GET_BLOCKS_PRE_IO was set to split an\nexisting large unwritten extent. However, EXT4_GET_BLOCKS_CONVERT was\nset when calling ext4_split_convert_extents(), which may potentially\nresult in stale data issues.\n\nAssume we have an unwritten extent, and then DIO writes the second half.\n\n   [UUUUUUUUUUUUUUUU] on-disk extent        U: unwritten extent\n   [UUUUUUUUUUUUUUUU] extent status tree\n            |<-   ->| ----> dio write this range\n\nFirst, ext4_iomap_alloc() call ext4_map_blocks() with\nEXT4_GET_BLOCKS_PRE_IO, EXT4_GET_BLOCKS_UNWRIT_EXT and\nEXT4_GET_BLOCKS_CREATE flags set. ext4_map_blocks() find this extent and\ncall ext4_split_convert_extents() with EXT4_GET_BLOCKS_CONVERT and the\nabove flags set.\n\nThen, ext4_split_convert_extents() calls ext4_split_extent() with\nEXT4_EXT_MAY_ZEROOUT, EXT4_EXT_MARK_UNWRIT2 and EXT4_EXT_DATA_VALID2\nflags set, and it calls ext4_split_extent_at() to split the second half\nwith EXT4_EXT_DATA_VALID2, EXT4_EXT_MARK_UNWRIT1, EXT4_EXT_MAY_ZEROOUT\nand EXT4_EXT_MARK_UNWRIT2 flags set. However, ext4_split_extent_at()\nfailed to insert extent since a temporary lack -ENOSPC. It zeroes out\nthe first half but convert the entire on-disk extent to written since\nthe EXT4_EXT_DATA_VALID2 flag set, but left the second half as unwritten\nin the extent status tree.\n\n   [0000000000SSSSSS]  data                S: stale data, 0: zeroed\n   [WWWWWWWWWWWWWWWW]  on-disk extent      W: written extent\n   [WWWWWWWWWWUUUUUU]  extent status tree\n\nFinally, if the DIO failed to write data to the disk, the stale data in\nthe second half will be exposed once the cached extent entry is gone.\n\nFix this issue by not passing EXT4_GET_BLOCKS_CONVERT when splitting\nan unwritten extent before submitting I/O, and make\next4_split_convert_extents() to zero out the entire extent range\nto zero for this case, and also mark the extent in the extent status\ntree for consistency."}],"providerMetadata":{"dateUpdated":"2026-05-27T12:18:43.844Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/77e407967cd872cd75d7e4a691908e49c8e6b4d4"},{"url":"https://git.kernel.org/stable/c/37555690f39f78ef69af347d9aff897e07445949"},{"url":"https://git.kernel.org/stable/c/67cdb7bd7442bd3cdc6d6088bbb2df9be2fe936c"},{"url":"https://git.kernel.org/stable/c/2920ec61c98b9476781359f05b94da84e80f54d4"},{"url":"https://git.kernel.org/stable/c/2698731d25823267c29190cb578da9296a0c0d7b"},{"url":"https://git.kernel.org/stable/c/716e7439a5a9b18c3ff882c2f8c834b9ced1aaec"},{"url":"https://git.kernel.org/stable/c/feaf2a80e78f89ee8a3464126077ba8683b62791"}],"title":"ext4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before submitting I/O","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-45985","datePublished":"2026-05-27T12:18:43.844Z","dateReserved":"2026-05-13T15:03:33.090Z","dateUpdated":"2026-05-27T12:18:43.844Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-27 14:17:15","lastModifiedDate":"2026-05-27 14:48:03","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"45985","Ordinal":"1","Title":"ext4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before su","CVE":"CVE-2026-45985","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"45985","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before submitting I/O\n\nWhen allocating blocks during within-EOF DIO and writeback with\ndioread_nolock enabled, EXT4_GET_BLOCKS_PRE_IO was set to split an\nexisting large unwritten extent. However, EXT4_GET_BLOCKS_CONVERT was\nset when calling ext4_split_convert_extents(), which may potentially\nresult in stale data issues.\n\nAssume we have an unwritten extent, and then DIO writes the second half.\n\n   [UUUUUUUUUUUUUUUU] on-disk extent        U: unwritten extent\n   [UUUUUUUUUUUUUUUU] extent status tree\n            |<-   ->| ----> dio write this range\n\nFirst, ext4_iomap_alloc() call ext4_map_blocks() with\nEXT4_GET_BLOCKS_PRE_IO, EXT4_GET_BLOCKS_UNWRIT_EXT and\nEXT4_GET_BLOCKS_CREATE flags set. ext4_map_blocks() find this extent and\ncall ext4_split_convert_extents() with EXT4_GET_BLOCKS_CONVERT and the\nabove flags set.\n\nThen, ext4_split_convert_extents() calls ext4_split_extent() with\nEXT4_EXT_MAY_ZEROOUT, EXT4_EXT_MARK_UNWRIT2 and EXT4_EXT_DATA_VALID2\nflags set, and it calls ext4_split_extent_at() to split the second half\nwith EXT4_EXT_DATA_VALID2, EXT4_EXT_MARK_UNWRIT1, EXT4_EXT_MAY_ZEROOUT\nand EXT4_EXT_MARK_UNWRIT2 flags set. However, ext4_split_extent_at()\nfailed to insert extent since a temporary lack -ENOSPC. It zeroes out\nthe first half but convert the entire on-disk extent to written since\nthe EXT4_EXT_DATA_VALID2 flag set, but left the second half as unwritten\nin the extent status tree.\n\n   [0000000000SSSSSS]  data                S: stale data, 0: zeroed\n   [WWWWWWWWWWWWWWWW]  on-disk extent      W: written extent\n   [WWWWWWWWWWUUUUUU]  extent status tree\n\nFinally, if the DIO failed to write data to the disk, the stale data in\nthe second half will be exposed once the cached extent entry is gone.\n\nFix this issue by not passing EXT4_GET_BLOCKS_CONVERT when splitting\nan unwritten extent before submitting I/O, and make\next4_split_convert_extents() to zero out the entire extent range\nto zero for this case, and also mark the extent in the extent status\ntree for consistency.","Type":"Description","Title":"ext4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before su"}]}}}