{"id":"CVE-2026-98398","revision":"d78b84839eca46478efb29913362a8c7","records":[{"revision":"d78b84839eca46478efb29913362a8c7","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98398","aliases":[],"title":"locking/lockdep: Invalidate stale class_cache entries for zapped classes","description":"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().","state":0,"publishedAt":"2026-10-14T13:25:59.676+00:00","modifiedAt":"2026-10-19T09:18:51.739+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/locking/lockdep.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4\",\n                            \"lessThan\": \"f8a1281ab82df5b51fd0384354d4b21daf2b7af0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4\",\n                            \"lessThan\": \"1c9d664e2e067fca69e5a41d68e23bbc66a583fe\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4\",\n                            \"lessThan\": \"6bc345f6d81ebe22e0f355c2a21d7e29691f9332\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4\",\n                            \"lessThan\": \"f63c86e9d267629758adaba18579e784ddd63c32\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4\",\n                            \"lessThan\": \"c7acfb04c7e2e2dea248282b21373d93296644dd\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4\",\n                            \"lessThan\": \"baa320fbb2f9fea50f5632a307da8ce84fbef5bd\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a0b0fd53e1e67639b303b15939b9c653dbe7a8c4\",\n                            \"lessThan\": \"02c6be7d675b21d81f0ba3a524346850a8c0e3bf\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/locking/lockdep.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.1\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.1\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.222\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.189\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.158\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.111\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.53\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.7\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/f8a1281ab82df5b51fd0384354d4b21daf2b7af0","https://git.kernel.org/stable/c/1c9d664e2e067fca69e5a41d68e23bbc66a583fe","https://git.kernel.org/stable/c/6bc345f6d81ebe22e0f355c2a21d7e29691f9332","https://git.kernel.org/stable/c/f63c86e9d267629758adaba18579e784ddd63c32","https://git.kernel.org/stable/c/c7acfb04c7e2e2dea248282b21373d93296644dd","https://git.kernel.org/stable/c/baa320fbb2f9fea50f5632a307da8ce84fbef5bd","https://git.kernel.org/stable/c/02c6be7d675b21d81f0ba3a524346850a8c0e3bf"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98398","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98398","identifiers":["CVE-2026-98398"]},"retained":false,"historicalAffected":[]}],"coverage":[]}