{"cve":"CVE-2026-46304","nvd":{"published":"2026-06-08T17:16:49.053","modified":"2026-10-19T20:18:41.483","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvmet: avoid recursive nvmet-wq flush in nvmet_ctrl_free\n\nnvmet_tcp_release_queue_work() runs on nvmet-wq and can drop the\nfinal controller reference through nvmet_cq_put(). If that triggers\nnvmet_ctrl_free(), the teardown path flushes ctrl->async_event_work on\nthe same nvmet-wq.\n\nCall chain:\n\n nvmet_tcp_schedule_release_queue()\n   kref_put(&queue->kref, nvmet_tcp_release_queue)\n     nvmet_tcp_release_queue()\n       queue_work(nvmet_wq, &queue->release_work) <--- nvmet_wq\n         process_one_work()\n           nvmet_tcp_release_queue_work()\n             nvmet_cq_put(&queue->nvme_cq)\n               nvmet_cq_destroy()\n                 nvmet_ctrl_put(cq->ctrl)\n                   nvmet_ctrl_free()\n                     flush_work(&ctrl->async_event_work) <--- nvmet_wq\n\n                      Previously Scheduled by :-\n\t\t        nvmet_add_async_event\n\t\t          queue_work(nvmet_wq, &ctrl->async_event_work);\n\nThis trips lockdep with a possible recursive locking warning.\n\n[ 5223.015876] run blktests nvme/003 at 2026-04-07 20:53:55\n[ 5223.061801] loop0: detected capacity change from 0 to 2097152\n[ 5223.072206] nvmet: adding nsid 1 to subsystem blktests-subsystem-1\n[ 5223.088368] nvmet_tcp: enabling port 0 (127.0.0.1:4420)\n[ 5223.126086] nvmet: Created discovery controller 1 for subsystem nqn.2014-08.org.nvmexpress.discovery for NQN nqn.2014-08.org.nvmexpress:uuid:0f01fb42-9f7f-4856-b0b3-51e60b8de349.\n[ 5223.128453] nvme nvme1: new ctrl: NQN \"nqn.2014-08.org.nvmexpress.discovery\", addr 127.0.0.1:4420, hostnqn: nqn.2014-08.org.nvmexpress:uuid:0f01fb42-9f7f-4856-b0b3-51e60b8de349\n[ 5233.199447] nvme nvme1: Removing ctrl: NQN \"nqn.2014-08.org.nvmexpress.discovery\"\n\n[ 5233.227718] ============================================\n[ 5233.231283] WARNING: possible recursive locking detected\n[ 5233.234696] 7.0.0-rc3nvme+ #20 Tainted: G           O     N\n[ 5233.238434] --------------------------------------------\n[ 5233.241852] kworker/u192:6/2413 is trying to acquire lock:\n[ 5233.245429] ffff888111632548 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: touch_wq_lockdep_map+0x26/0x90\n[ 5233.251438]\n               but task is already holding lock:\n[ 5233.255254] ffff888111632548 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: process_one_work+0x5cc/0x6e0\n[ 5233.261125]\n               other info that might help us debug this:\n[ 5233.265333]  Possible unsafe locking scenario:\n\n[ 5233.269217]        CPU0\n[ 5233.270795]        ----\n[ 5233.272436]   lock((wq_completion)nvmet-wq);\n[ 5233.275241]   lock((wq_completion)nvmet-wq);\n[ 5233.278020]\n                *** DEADLOCK ***\n\n[ 5233.281793]  May be due to missing lock nesting notation\n\n[ 5233.286195] 3 locks held by kworker/u192:6/2413:\n[ 5233.289192]  #0: ffff888111632548 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: process_one_work+0x5cc/0x6e0\n[ 5233.294569]  #1: ffffc9000e2a7e40 ((work_completion)(&queue->release_work)){+.+.}-{0:0}, at: process_one_work+0x1c5/0x6e0\n[ 5233.300128]  #2: ffffffff82d7dc40 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x62/0x530\n[ 5233.304290]\n               stack backtrace:\n[ 5233.306520] CPU: 4 UID: 0 PID: 2413 Comm: kworker/u192:6 Tainted: G           O     N  7.0.0-rc3nvme+ #20 PREEMPT(full)\n[ 5233.306524] Tainted: [O]=OOT_MODULE, [N]=TEST\n[ 5233.306525] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014\n[ 5233.306527] Workqueue: nvmet-wq nvmet_tcp_release_queue_work [nvmet_tcp]\n[ 5233.306532] Call Trace:\n[ 5233.306534]  <TASK>\n[ 5233.306536]  dump_stack_lvl+0x73/0xb0\n[ 5233.306552]  print_deadlock_bug+0x225/0x2f0\n[ 5233.306556]  __lock_acquire+0x13f0/0x2290\n[ 5233.306563]  lock_acquire+0xd0/0x300\n[ 5233.306565]  ? touch_wq_lockdep_map+0x26/0x90\n[ 5233.306571]  ? __flush_work+0x20b/0x530\n[ 5233.306573]  ? touch_wq_lockdep_map+0x26/0x90\n[ 5233.306577]  touch_wq_lockdep_map+0x3b/0x90\n[ 5233.306580]  ? touch_wq_lockdep_map+0x26/0x90\n[ 52\n---truncated---","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-667"],"references":["https://git.kernel.org/stable/c/551f445a56a11a6457550cddcf39c9ebb8bcacc6","https://git.kernel.org/stable/c/781f47d641432c26c19625b2cdd7f40825097592","https://git.kernel.org/stable/c/8d66ba89480ff098a58d79003a505f383aa4e920","https://git.kernel.org/stable/c/9a4d7222c0955b221e38bb66d10e6bccb672c8a1","https://git.kernel.org/stable/c/a696fbbd5240b4ac9b166f7bd4c550882ff543f1"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-46304","score":0.00349,"percentile":0.28271,"date":"2026-10-26"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}