{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a0b0fd53e1e67639b303b15939b9c653dbe7a8c4"
            },
            {
              "fixed": "f8a1281ab82df5b51fd0384354d4b21daf2b7af0"
            },
            {
              "fixed": "1c9d664e2e067fca69e5a41d68e23bbc66a583fe"
            },
            {
              "fixed": "6bc345f6d81ebe22e0f355c2a21d7e29691f9332"
            },
            {
              "fixed": "f63c86e9d267629758adaba18579e784ddd63c32"
            },
            {
              "fixed": "c7acfb04c7e2e2dea248282b21373d93296644dd"
            },
            {
              "fixed": "baa320fbb2f9fea50f5632a307da8ce84fbef5bd"
            },
            {
              "fixed": "02c6be7d675b21d81f0ba3a524346850a8c0e3bf"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.1.0"
            },
            {
              "fixed": "5.15.222"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.189"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.158"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.111"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.53"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98398.json"
  },
  "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   \u003cIRQ\u003e\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-\u003eclass_cache[subclass] != NULL, skipping register_lock_class()\nand assigning hlock-\u003eclass_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-\u003ekey 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().",
  "id": "CVE-2026-98398",
  "modified": "2026-10-15T02:31:14.009934312Z",
  "published": "2026-10-14T13:25:59.676Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/02c6be7d675b21d81f0ba3a524346850a8c0e3bf"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1c9d664e2e067fca69e5a41d68e23bbc66a583fe"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6bc345f6d81ebe22e0f355c2a21d7e29691f9332"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/baa320fbb2f9fea50f5632a307da8ce84fbef5bd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c7acfb04c7e2e2dea248282b21373d93296644dd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f63c86e9d267629758adaba18579e784ddd63c32"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f8a1281ab82df5b51fd0384354d4b21daf2b7af0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98398.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98398"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "locking/lockdep: Invalidate stale class_cache entries for zapped classes"
}