{"id":"AZL-109194","summary":"CVE-2026-98580 affecting package kernel 6.6.157.1-1","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":"2026-10-19T14:16:31.932929586Z","published":"2026-10-18T16:17:10Z","upstream":["CVE-2026-98580"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98580"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-109194.json"}}],"schema_version":"1.9.0"}