{"id":"CVE-2026-89834","state":"PUBLISHED","title":"f2fs: fix to migrate all curseg types during free_segment_range","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to migrate all curseg types during free_segment_range\n\nIn free_segment_range(), the curseg evacuation loop only iterates up to\nNR_CURSEG_PERSIST_TYPE (0..5), missing non-persistent in-memory curseg\ntypes such as CURSEG_COLD_DATA_PINNED and CURSEG_ALL_DATA_ATGC.\n\nEven though these in-memory curseg types are not saved in the on-disk\ncheckpoint header, they still occupy active physical segments at runtime.\nIf an active in-memory curseg happens to be allocated within the segment\nrange being truncated during filesystem shrink, failing to evacuate it\nwill cause subsequent writes to the curseg attempting out-of-bounds I/O\non the truncated storage range.\n\nFix this by expanding the curseg evacuation loop upper bound to\nNR_CURSEG_TYPE to ensure all active curseg types are safely migrated\nout of the target range.","publishedAt":"2026-09-16T10:31:07.093Z","updatedAt":"2026-10-30T12:33:13.082Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"7ffac0deea2d84cf79051f16fed8e215c4bcf0e6","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"d358d2fc6be11eefde5eb1286f1c43a6d0330db6","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"3b85edf3391f3e1f624f409a7d2d239885f567b7","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"b8ae1228c153622afa71a179c9d4dc268117e0f0","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"b9776094aa7118e8e5dfdcd791ffc8330c5ca408","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"8ec06f50ddd8d201bd7e55b896ae28ed9d4cb7d1","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/gc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.10","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/gc.c"]}],"references":["https://git.kernel.org/stable/c/7ffac0deea2d84cf79051f16fed8e215c4bcf0e6","https://git.kernel.org/stable/c/d358d2fc6be11eefde5eb1286f1c43a6d0330db6","https://git.kernel.org/stable/c/3b85edf3391f3e1f624f409a7d2d239885f567b7","https://git.kernel.org/stable/c/b8ae1228c153622afa71a179c9d4dc268117e0f0","https://git.kernel.org/stable/c/b9776094aa7118e8e5dfdcd791ffc8330c5ca408","https://git.kernel.org/stable/c/8ec06f50ddd8d201bd7e55b896ae28ed9d4cb7d1"],"weaknesses":[],"ingestedAt":"2026-10-30T12:52:04.348Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89834.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89834","state":"PUBLISHED","datePublished":"2026-09-16T10:31:07.093Z","dateUpdated":"2026-10-30T12:33:13.082Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.769Z"},"containers":{"cna":{"title":"f2fs: fix to migrate all curseg types during free_segment_range","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to migrate all curseg types during free_segment_range\n\nIn free_segment_range(), the curseg evacuation loop only iterates up to\nNR_CURSEG_PERSIST_TYPE (0..5), missing non-persistent in-memory curseg\ntypes such as CURSEG_COLD_DATA_PINNED and CURSEG_ALL_DATA_ATGC.\n\nEven though these in-memory curseg types are not saved in the on-disk\ncheckpoint header, they still occupy active physical segments at runtime.\nIf an active in-memory curseg happens to be allocated within the segment\nrange being truncated during filesystem shrink, failing to evacuate it\nwill cause subsequent writes to the curseg attempting out-of-bounds I/O\non the truncated storage range.\n\nFix this by expanding the curseg evacuation loop upper bound to\nNR_CURSEG_TYPE to ensure all active curseg types are safely migrated\nout of the target range."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"7ffac0deea2d84cf79051f16fed8e215c4bcf0e6","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"d358d2fc6be11eefde5eb1286f1c43a6d0330db6","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"3b85edf3391f3e1f624f409a7d2d239885f567b7","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"b8ae1228c153622afa71a179c9d4dc268117e0f0","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"b9776094aa7118e8e5dfdcd791ffc8330c5ca408","versionType":"git"},{"version":"d0b9e42ab6155dc05fc83f00af9f45d4dd02264d","status":"affected","lessThan":"8ec06f50ddd8d201bd7e55b896ae28ed9d4cb7d1","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/gc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.10","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/gc.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7ffac0deea2d84cf79051f16fed8e215c4bcf0e6"},{"url":"https://git.kernel.org/stable/c/d358d2fc6be11eefde5eb1286f1c43a6d0330db6"},{"url":"https://git.kernel.org/stable/c/3b85edf3391f3e1f624f409a7d2d239885f567b7"},{"url":"https://git.kernel.org/stable/c/b8ae1228c153622afa71a179c9d4dc268117e0f0"},{"url":"https://git.kernel.org/stable/c/b9776094aa7118e8e5dfdcd791ffc8330c5ca408"},{"url":"https://git.kernel.org/stable/c/8ec06f50ddd8d201bd7e55b896ae28ed9d4cb7d1"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:33:13.082Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}