{"api_version":"1","generated_at":"2026-10-22T02:29:52+00:00","cve":"CVE-2025-68240","urls":{"html":"https://cve.report/CVE-2025-68240","api":"https://cve.report/api/cve/CVE-2025-68240.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2025-68240","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-68240"},"summary":{"title":"nilfs2: avoid having an active sc_timer before freeing sci","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: avoid having an active sc_timer before freeing sci\n\nBecause kthread_stop did not stop sc_task properly and returned -EINTR,\nthe sc_timer was not properly closed, ultimately causing the problem [1]\nreported by syzbot when freeing sci due to the sc_timer not being closed.\n\nBecause the thread sc_task main function nilfs_segctor_thread() returns 0\nwhen it succeeds, when the return value of kthread_stop() is not 0 in\nnilfs_segctor_destroy(), we believe that it has not properly closed\nsc_timer.\n\nWe use timer_shutdown_sync() to sync wait for sc_timer to shutdown, and\nset the value of sc_task to NULL under the protection of lock\nsc_state_lock, so as to avoid the issue caused by sc_timer not being\nproperly shutdowned.\n\n[1]\nODEBUG: free active (active state 0) object: 00000000dacb411a object type: timer_list hint: nilfs_construction_timeout\nCall trace:\n nilfs_segctor_destroy fs/nilfs2/segment.c:2811 [inline]\n nilfs_detach_log_writer+0x668/0x8cc fs/nilfs2/segment.c:2877\n nilfs_put_super+0x4c/0x12c fs/nilfs2/super.c:509","state":"PUBLISHED","assigner":"Linux","published_at":"2025-12-16 15:15:53","updated_at":"2026-10-14 13:10:00"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/36049e81dc7f077e0e24d5b9688a7458beacef8f","name":"https://git.kernel.org/stable/c/36049e81dc7f077e0e24d5b9688a7458beacef8f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2f65799e2a736d556d306440c4e1e8906736117a","name":"https://git.kernel.org/stable/c/2f65799e2a736d556d306440c4e1e8906736117a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9a6b60cb147d53968753a34805211d2e5e08c027","name":"https://git.kernel.org/stable/c/9a6b60cb147d53968753a34805211d2e5e08c027","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-68240","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-68240","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3f66cc261ccb54a8e4d8d5aa51c389c19453b00c 36049e81dc7f077e0e24d5b9688a7458beacef8f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3f66cc261ccb54a8e4d8d5aa51c389c19453b00c 2f65799e2a736d556d306440c4e1e8906736117a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3f66cc261ccb54a8e4d8d5aa51c389c19453b00c 9a6b60cb147d53968753a34805211d2e5e08c027 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.59 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.17.9 6.17.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/nilfs2/segment.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"36049e81dc7f077e0e24d5b9688a7458beacef8f","status":"affected","version":"3f66cc261ccb54a8e4d8d5aa51c389c19453b00c","versionType":"git"},{"lessThan":"2f65799e2a736d556d306440c4e1e8906736117a","status":"affected","version":"3f66cc261ccb54a8e4d8d5aa51c389c19453b00c","versionType":"git"},{"lessThan":"9a6b60cb147d53968753a34805211d2e5e08c027","status":"affected","version":"3f66cc261ccb54a8e4d8d5aa51c389c19453b00c","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/nilfs2/segment.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.12"},{"lessThan":"6.12","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.59","versionType":"semver"},{"lessThanOrEqual":"6.17.*","status":"unaffected","version":"6.17.9","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.18","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.59","versionStartIncluding":"6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.17.9","versionStartIncluding":"6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18","versionStartIncluding":"6.12","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: avoid having an active sc_timer before freeing sci\n\nBecause kthread_stop did not stop sc_task properly and returned -EINTR,\nthe sc_timer was not properly closed, ultimately causing the problem [1]\nreported by syzbot when freeing sci due to the sc_timer not being closed.\n\nBecause the thread sc_task main function nilfs_segctor_thread() returns 0\nwhen it succeeds, when the return value of kthread_stop() is not 0 in\nnilfs_segctor_destroy(), we believe that it has not properly closed\nsc_timer.\n\nWe use timer_shutdown_sync() to sync wait for sc_timer to shutdown, and\nset the value of sc_task to NULL under the protection of lock\nsc_state_lock, so as to avoid the issue caused by sc_timer not being\nproperly shutdowned.\n\n[1]\nODEBUG: free active (active state 0) object: 00000000dacb411a object type: timer_list hint: nilfs_construction_timeout\nCall trace:\n nilfs_segctor_destroy fs/nilfs2/segment.c:2811 [inline]\n nilfs_detach_log_writer+0x668/0x8cc fs/nilfs2/segment.c:2877\n nilfs_put_super+0x4c/0x12c fs/nilfs2/super.c:509"}],"providerMetadata":{"dateUpdated":"2026-05-11T21:49:32.618Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/36049e81dc7f077e0e24d5b9688a7458beacef8f"},{"url":"https://git.kernel.org/stable/c/2f65799e2a736d556d306440c4e1e8906736117a"},{"url":"https://git.kernel.org/stable/c/9a6b60cb147d53968753a34805211d2e5e08c027"}],"title":"nilfs2: avoid having an active sc_timer before freeing sci","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2025-68240","datePublished":"2025-12-16T14:21:17.710Z","dateReserved":"2025-12-16T13:41:40.263Z","dateUpdated":"2026-05-11T21:49:32.618Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2025-12-16 15:15:53","lastModifiedDate":"2026-10-14 13:10:00","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2025","CveId":"68240","Ordinal":"1","Title":"nilfs2: avoid having an active sc_timer before freeing sci","CVE":"CVE-2025-68240","Year":"2025"},"notes":[{"CveYear":"2025","CveId":"68240","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: avoid having an active sc_timer before freeing sci\n\nBecause kthread_stop did not stop sc_task properly and returned -EINTR,\nthe sc_timer was not properly closed, ultimately causing the problem [1]\nreported by syzbot when freeing sci due to the sc_timer not being closed.\n\nBecause the thread sc_task main function nilfs_segctor_thread() returns 0\nwhen it succeeds, when the return value of kthread_stop() is not 0 in\nnilfs_segctor_destroy(), we believe that it has not properly closed\nsc_timer.\n\nWe use timer_shutdown_sync() to sync wait for sc_timer to shutdown, and\nset the value of sc_task to NULL under the protection of lock\nsc_state_lock, so as to avoid the issue caused by sc_timer not being\nproperly shutdowned.\n\n[1]\nODEBUG: free active (active state 0) object: 00000000dacb411a object type: timer_list hint: nilfs_construction_timeout\nCall trace:\n nilfs_segctor_destroy fs/nilfs2/segment.c:2811 [inline]\n nilfs_detach_log_writer+0x668/0x8cc fs/nilfs2/segment.c:2877\n nilfs_put_super+0x4c/0x12c fs/nilfs2/super.c:509","Type":"Description","Title":"nilfs2: avoid having an active sc_timer before freeing sci"}]}}}