This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
History

Wed, 04 Nov 2026 18:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: io-wq: order the exit bit against worker creation task work io_wq_exit_workers() cancels task work for queued worker creation with task_work_cancel_match(). That has a plain load of task->task_works. io_queue_worker_create() adds the new entry and tests IO_WQ_BIT_EXIT to cancel it if the workqueue is already on its way out. That must be ordered. task_work_add() has a full barrier via cmpxchg(). But io_wq_exit_start() sets the bit with set_bit() which doesn't have any memory ordering. So afaict, on weakly ordered architectures the exiting task may load task_works before the store of the bit is visible. The other side tests the bit before the store is visible as well. So the entry remains queued with worker_refs and the exiting task waits on worker_done indefinitely. If the task still has rings then io_uring_del_tctx_node() provides the barrier via test_and_set_bit() in io_wq_set_exit_on_idle(). When it has closed all rings though that barrier is gone. Add the barrier after the set_bit(). This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
Title io-wq: order the exit bit against worker creation task work Kernel workqueue deadlock caused by missing memory barrier during I/O worker cleanup
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Tue, 03 Nov 2026 19:30:00 +0000


Tue, 03 Nov 2026 13:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-665

Tue, 03 Nov 2026 13:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux linux
Vendors & Products Linux linux

Tue, 03 Nov 2026 11:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: io-wq: order the exit bit against worker creation task work io_wq_exit_workers() cancels task work for queued worker creation with task_work_cancel_match(). That has a plain load of task->task_works. io_queue_worker_create() adds the new entry and tests IO_WQ_BIT_EXIT to cancel it if the workqueue is already on its way out. That must be ordered. task_work_add() has a full barrier via cmpxchg(). But io_wq_exit_start() sets the bit with set_bit() which doesn't have any memory ordering. So afaict, on weakly ordered architectures the exiting task may load task_works before the store of the bit is visible. The other side tests the bit before the store is visible as well. So the entry remains queued with worker_refs and the exiting task waits on worker_done indefinitely. If the task still has rings then io_uring_del_tctx_node() provides the barrier via test_and_set_bit() in io_wq_set_exit_on_idle(). When it has closed all rings though that barrier is gone. Add the barrier after the set_bit().
Title io-wq: order the exit bit against worker creation task work
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

cve-icon MITRE

Status: REJECTED

Assigner: Linux

Published: 2026-11-03T11:14:30.233Z

Updated: 2026-11-04T18:21:48.672Z

Reserved: 2026-09-25T10:25:14.403Z

Link: CVE-2026-99243

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-11-03T12:17:30.553

Modified: 2026-11-03T20:18:30.607

Link: CVE-2026-99243

cve-icon Redhat

No data.