{"cve":"CVE-2026-90276","nvd":{"published":"2026-09-17T17:17:24.247","modified":"2026-10-19T09:19:21.170","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmd/md-llbitmap: stop daemon timer rearm on destroy\n\nllbitmap_destroy() deletes pending_timer before flushing\nmd_llbitmap_io_wq. However, daemon_work can still be queued or running\nafter the timer has been deleted, and the daemon path can arm\npending_timer again when it finds dirty chunks that are not ready to\nflush yet.\n\nIf that happens during teardown, pending_timer can remain armed after\nllbitmap is freed and later dereference freed memory.\n\nAdd a BITMAP_SHUTDOWN bit to llbitmap->flags, set it before deleting\nthe timer, and make the timer and daemon paths stop queueing or rearming\nwork once teardown starts. Cancel daemon_work before flushing the shared\nworkqueue so no already queued daemon instance can race with the free.\nUse timer_shutdown_sync() so a daemon instance that passed the shutdown\ncheck before teardown cannot rearm the timer afterward.\n\nBITMAP_SHUTDOWN is a runtime-only state. Mask it out when reading and\nupdating the llbitmap superblock so the shutdown state is never loaded\nfrom disk or persisted to disk.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/5553d64e01d9a995be6c3de38501c6dd4ceede3b","https://git.kernel.org/stable/c/bb7f92d58fca9a9f06f3f51a82481c5f0bbbd46c","https://git.kernel.org/stable/c/c55aa6c17f019b6296952d336939891efa084c06"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-90276","score":0.00206,"percentile":0.10634,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}