{"schema":"threatline.record/2","record":{"id":"CVE-2026-98398","aliases":[],"summary":"locking/lockdep: Invalidate stale class_cache entries for zapped classes","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nlocking/lockdep: Invalidate stale class_cache entries for zapped classes\n\nsyzbot reported a lockdep splat hitting DEBUG_LOCKS_WARN_ON(1) in\nhlock_class() due to an invalid class_idx:\n\n  WARNING: kernel/locking/lockdep.c:238 at __lock_acquire+0x382/0x2cf0 kernel/locking/lockdep.c:5203\n  Workqueue: wg-crypt-wg0 wg_packet_tx_worker\n  RIP: 0010:hlock_class kernel/locking/lockdep.c:238 [inline]\n  RIP: 0010:check_wait_context kernel/locking/lockdep.c:4870 [inline]\n  RIP: 0010:__lock_acquire+0x389/0x2cf0 kernel/locking/lockdep.c:5203\n  Call Trace:\n   <IRQ>\n   lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886\n   _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:173\n   tcp_tsq_handler+0x29/0x200 net/ipv4/tcp_output.c:1291\n   tcp_tsq_workfn+0x384/0x410 net/ipv4/tcp_output.c:1325\n   ...\n\nWhen a lock class is zapped (e.g. during module unload or key\nunregistration), zap_class() clears the class's bit in\nlock_classes_in_use and removes it from the class hash table.\nHowever, existing lockdep_map instances embedded in data structures\nmay still retain a pointer to the zapped class in their class_cache[]\narray.\n\nWhen __lock_acquire() subsequently runs on such a lock, it finds\nlock->class_cache[subclass] != NULL, skipping register_lock_class()\nand assigning hlock->class_idx to the index of the zapped class. When\ncheck_wait_context() or hlock_class() inspects the held_lock, it finds\n!test_bit(class_idx, lock_classes_in_use) and warns. Furthermore, if\nthe zapped slot is subsequently re-allocated to an unrelated lock key,\nthe stale class_cache entry would erroneously match the unrelated\nclass (ABA issue).\n\nAdd lock_class_cache_is_valid() to validate that the cached class is\nwithin lock_classes bounds, still allocated in lock_classes_in_use\n(using uninstrumented arch_test_bit() in __always_inline context so it\nis safe in noinstr contexts like match_held_lock()), and that\nclass->key matches the expected subkey (taking lockdep_set_subclass()\noverrides into account). Also use READ_ONCE()/WRITE_ONCE() when\naccessing class_cache[].  If the entry is invalid or stale, fall back\nto register_lock_class() / look_up_lock_class().","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98398","source_modified_at":"2026-10-19T09:18:51.739Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4","lessThan":"f8a1281ab82df5b51fd0384354d4b21daf2b7af0","status":"affected","versionType":"git"},{"version":"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4","lessThan":"1c9d664e2e067fca69e5a41d68e23bbc66a583fe","status":"affected","versionType":"git"},{"version":"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4","lessThan":"6bc345f6d81ebe22e0f355c2a21d7e29691f9332","status":"affected","versionType":"git"},{"version":"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4","lessThan":"f63c86e9d267629758adaba18579e784ddd63c32","status":"affected","versionType":"git"},{"version":"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4","lessThan":"c7acfb04c7e2e2dea248282b21373d93296644dd","status":"affected","versionType":"git"},{"version":"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4","lessThan":"baa320fbb2f9fea50f5632a307da8ce84fbef5bd","status":"affected","versionType":"git"},{"version":"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4","lessThan":"02c6be7d675b21d81f0ba3a524346850a8c0e3bf","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98398","source_modified_at":"2026-10-19T09:18:51.739Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"5.1","status":"affected"},{"version":"0","lessThan":"5.1","status":"unaffected","versionType":"semver"},{"version":"5.15.222","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.189","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.158","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.111","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.53","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.7","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-2026-98398","source_modified_at":"2026-10-19T09:18:51.739Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"1c9d664e2e067fca69e5a41d68e23bbc66a583fe","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98398","source_modified_at":"2026-10-19T09:18:51.739Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"6bc345f6d81ebe22e0f355c2a21d7e29691f9332","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98398","source_modified_at":"2026-10-19T09:18:51.739Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"02c6be7d675b21d81f0ba3a524346850a8c0e3bf","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.00215,"percentile":0.11297,"score_date":"2026-10-23"},"published_at":"2026-10-14T13:25:59.676Z","modified_at":"2026-10-19T09:18:51.739Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98398","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:18:51.739Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98398","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/f8a1281ab82df5b51fd0384354d4b21daf2b7af0"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/1c9d664e2e067fca69e5a41d68e23bbc66a583fe"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/6bc345f6d81ebe22e0f355c2a21d7e29691f9332"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/f63c86e9d267629758adaba18579e784ddd63c32"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/c7acfb04c7e2e2dea248282b21373d93296644dd"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/baa320fbb2f9fea50f5632a307da8ce84fbef5bd"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/02c6be7d675b21d81f0ba3a524346850a8c0e3bf"}],"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":"2026-10-19T09:18:51.739Z","content_hash":"48fc6496358dcf5eff214068b2644b80bf5e99b78ca09a5292981cc5a46b9908"}}