{"schema":"threatline.record/2","record":{"id":"CVE-2026-98986","aliases":[],"summary":"namespace: remove the fsnotify marks of a mount namespace in process context","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: remove the fsnotify marks of a mount namespace in process context\n\nmnt_ns_release() drops the last passive reference of a mount namespace\nand removes its fanotify marks via fsnotify_mntns_delete(). That takes\nthe mutex of every group with a mark on the namespace and the spinlock\nof the connector. Fine from process context. But mnt_ns_tree_remove()\nhands the reference the namespace was allocated with to call_rcu() and\nso the marks are removed from the RCU softirq:\n\n  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:623\n  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/3\n   __mutex_lock+0x113/0x24b0\n   fsnotify_destroy_marks+0x11b/0x3d0\n   mnt_ns_release_rcu+0x57/0xa0\n   rcu_core+0x6b6/0x1e40\n\nand lockdep complains about the connector lock being taken from softirq\ncontext. A fanotify group with a FAN_MARK_MNTNS mark on the mount\nnamespace of another task is all that's needed. Root in a user\nnamespace can do that for a mount namespace it owns. The task exits and\nthe namespace is freed with the mark still on it.\n\nRemove the marks in free_mnt_ns() before the namespace is handed to RCU.\nThat runs in process context once the last active reference is gone. A\nmark is added through a file descriptor to the namespace which holds an\nactive reference so no mark can show up after that.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98986","source_modified_at":"2026-10-23T12:20:04.966Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[{"version":"bf630c40164162ba1d3933c2f5e3397d083e0948","lessThan":"888363d74c3b5d32e2accf217add70f8b38e0e2b","status":"affected","versionType":"git"},{"version":"bf630c40164162ba1d3933c2f5e3397d083e0948","lessThan":"9e820a6becdd955a04adbedfd767253a47eedd9e","status":"affected","versionType":"git"},{"version":"bf630c40164162ba1d3933c2f5e3397d083e0948","lessThan":"1a116222acdcc1bc1a8350727ae6f28907d44594","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98986","source_modified_at":"2026-10-23T12:20:04.966Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"Linux","vendor":"Linux","versions":[{"version":"6.15","status":"affected"},{"version":"0","lessThan":"6.15","status":"unaffected","versionType":"semver"},{"version":"6.18.57","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.11","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98986","source_modified_at":"2026-10-23T12:20:04.966Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"888363d74c3b5d32e2accf217add70f8b38e0e2b","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98986","source_modified_at":"2026-10-23T12:20:04.966Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"9e820a6becdd955a04adbedfd767253a47eedd9e","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98986","source_modified_at":"2026-10-23T12:20:04.966Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"Linux","ecosystem":null},"version":"1a116222acdcc1bc1a8350727ae6f28907d44594","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":null,"percentile":null,"score_date":null},"published_at":"2026-10-23T12:20:04.966Z","modified_at":"2026-10-23T12:20:04.966Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98986","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T12:20:04.966Z"}],"sources":["CVE List"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/888363d74c3b5d32e2accf217add70f8b38e0e2b"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/9e820a6becdd955a04adbedfd767253a47eedd9e"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/1a116222acdcc1bc1a8350727ae6f28907d44594"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-23T12:20:04.966Z","content_hash":"a17dd03e4327e13ba6dafa33b59ef115c75a13f575ab2c6531b6f2eff131a357"}}