{"id":"CVE-2026-99054","published":"2026-10-23T13:17:29.013","lastModified":"2026-10-24T14:16:54.053","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: destroy topsrv workqueues before closing connections\n\ntipc_topsrv_stop() closed subscriber connections while the topology\nserver's send and receive workqueues were still running. Socket\ncallbacks and subscription events could then queue more work, and\nin-flight send/recv work could drop the last connection reference\nduring the conn_idr walk.\n\nThat race produced several teardown failures: refcount_t addition on\n0 from conn_get() on a connection whose release was blocked on\nidr_lock, a subsequent use-after-free in tipc_conn_close(),\nqueue_work() on an already destroyed workqueue from the listener\ndata-ready callback, and an RCU stall in tipc_topsrv_exit_net()\nwhile the walk spun under idr_lock.\n\nClear srv->listener under idr_lock so it acts as a shutdown flag,\nskip queue_work() once it is NULL, destroy the workqueues to flush\nin-flight work, and only then close the remaining connections.\nRefuse tipc_conn_lookup() after that flag is cleared, and drop\nidr_lock when the teardown walk finds no connection, so an\nin-flight subscription event cannot pin idr_in_use while the\nwalk holds the lock.\n\nv3 supersedes the narrower in-thread diff Tung Quang Nguyen\nposted on 2026-09-23. It keeps his teardown order and adds the\nlookup refusal and the empty-idr unlock.","cvssScore":7.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e","tags":[]},{"url":"https://git.kernel.org/stable/c/3acdd44385bc7e2e57605e073691ce69cc5a960d","tags":[]},{"url":"https://git.kernel.org/stable/c/7f796bb3b440d7f1b14c0e3b520462eb34f553af","tags":[]},{"url":"https://git.kernel.org/stable/c/da9c16568bc79140a54c1f5fcf07a0305df47b37","tags":[]},{"url":"https://git.kernel.org/stable/c/fb717c536af2aafeca520ff11d1e0f25f7ab8fa9","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}