{"id":"CVE-2026-98580","summary":"nfc: llcp: Fix race condition in accept_queue lifecycle","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfc: llcp: Fix race condition in accept_queue lifecycle\n\nIn nfc_llcp_socket_release(), sockets and listener accept queues are\nwalked under the local sockets rwlock and bh_lock_sock().  However,\nbh_lock_sock() does not synchronise against process-context lock_sock()\nheld by nfc_llcp_accept_dequeue() during accept().  Because\nsocket_release() does not check sock_owned_by_user(), both paths can\nconcurrently unlink and release the same child socket, resulting in\nuse-after-free or a NULL pointer dereference of child-\u003eparent in\nnfc_llcp_accept_unlink().\n\nFix this synchronisation race by having nfc_llcp_socket_release() use\nprocess-context lock_sock() instead of bh_lock_sock():\n\n1. Pop sockets from the local sockets list under the write lock using\n   nfc_llcp_sock_list_pop() so lock_sock() can be acquired without\n   holding the rwlock.\n\n2. Because lock_sock() can sleep, defer the final release of the\n   nfc_llcp_local structure to a workqueue (release_work).  This avoids\n   a sleeping-in-atomic bug when the last local reference is dropped\n   from softirq context.  Additionally, hold a single device reference\n   on local from registration until final destruction.\n\n3. In nfc_llcp_local_get(), use kref_get_unless_zero() to prevent\n   resurrecting a local object whose teardown has been scheduled.\n\n4. In llcp_sock_accept(), verify that the listener socket state is still\n   LLCP_LISTEN after waking from schedule_timeout() to prevent hangs if\n   the listener is closed concurrently.\n\n5. When unlinking unaccepted child sockets during listener release,\n   unlink them from local-\u003esockets, call sock_orphan(), and drop their\n   initial sk_alloc creation reference via sock_put().\n\n6. Make nfc_llcp_accept_unlink() idempotent by guarding parent access with\n   a NULL check.","modified":"2026-10-20T02:30:40.971988586Z","published":"2026-10-18T15:18:53.819Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98580.json"},"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/41256821762a7114906b178826d17098e2fa5992"},{"type":"WEB","url":"https://git.kernel.org/stable/c/53867f6acb1af7f12d6485fa8a2819318f89083b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/54adcabb0f1deef1bdae5fc64779ed6d442721c9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7c938aad5108382c6ad7453c4b5ee8ae3f3252ed"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c3eef2f988a3db9690369d7cef9a3344dd9788d3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d2093a0981138876212bc5f473bdbfba0786e064"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d5e1c92d09caed19f2988739695ce611a86ba6f8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/da8a07757383614a8380a0f7dd54749d2687b82e"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98580.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98580"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"50b78b2a6500d0e97c204c1b6c51df8c17358bbe"},{"fixed":"54adcabb0f1deef1bdae5fc64779ed6d442721c9"},{"fixed":"7c938aad5108382c6ad7453c4b5ee8ae3f3252ed"},{"fixed":"d2093a0981138876212bc5f473bdbfba0786e064"},{"fixed":"41256821762a7114906b178826d17098e2fa5992"},{"fixed":"53867f6acb1af7f12d6485fa8a2819318f89083b"},{"fixed":"da8a07757383614a8380a0f7dd54749d2687b82e"},{"fixed":"d5e1c92d09caed19f2988739695ce611a86ba6f8"},{"fixed":"c3eef2f988a3db9690369d7cef9a3344dd9788d3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98580.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.7.0"},{"fixed":"5.10.271"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"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":"6.12.112"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.55"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.9"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98580.json"}}],"schema_version":"1.9.0"}