CVE-2026-46304 (GCVE-0-2026-46304)
Vulnerability from cvelistv5
Published
2026-06-08 15:46
Modified
2026-08-05 12:31
Summary
In the Linux kernel, the following vulnerability has been resolved: nvmet: avoid recursive nvmet-wq flush in nvmet_ctrl_free nvmet_tcp_release_queue_work() runs on nvmet-wq and can drop the final controller reference through nvmet_cq_put(). If that triggers nvmet_ctrl_free(), the teardown path flushes ctrl->async_event_work on the same nvmet-wq. Call chain: nvmet_tcp_schedule_release_queue() kref_put(&queue->kref, nvmet_tcp_release_queue) nvmet_tcp_release_queue() queue_work(nvmet_wq, &queue->release_work) <--- nvmet_wq process_one_work() nvmet_tcp_release_queue_work() nvmet_cq_put(&queue->nvme_cq) nvmet_cq_destroy() nvmet_ctrl_put(cq->ctrl) nvmet_ctrl_free() flush_work(&ctrl->async_event_work) <--- nvmet_wq Previously Scheduled by :- nvmet_add_async_event queue_work(nvmet_wq, &ctrl->async_event_work); This trips lockdep with a possible recursive locking warning. [ 5223.015876] run blktests nvme/003 at 2026-04-07 20:53:55 [ 5223.061801] loop0: detected capacity change from 0 to 2097152 [ 5223.072206] nvmet: adding nsid 1 to subsystem blktests-subsystem-1 [ 5223.088368] nvmet_tcp: enabling port 0 (127.0.0.1:4420) [ 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. [ 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 [ 5233.199447] nvme nvme1: Removing ctrl: NQN "nqn.2014-08.org.nvmexpress.discovery" [ 5233.227718] ============================================ [ 5233.231283] WARNING: possible recursive locking detected [ 5233.234696] 7.0.0-rc3nvme+ #20 Tainted: G O N [ 5233.238434] -------------------------------------------- [ 5233.241852] kworker/u192:6/2413 is trying to acquire lock: [ 5233.245429] ffff888111632548 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: touch_wq_lockdep_map+0x26/0x90 [ 5233.251438] but task is already holding lock: [ 5233.255254] ffff888111632548 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: process_one_work+0x5cc/0x6e0 [ 5233.261125] other info that might help us debug this: [ 5233.265333] Possible unsafe locking scenario: [ 5233.269217] CPU0 [ 5233.270795] ---- [ 5233.272436] lock((wq_completion)nvmet-wq); [ 5233.275241] lock((wq_completion)nvmet-wq); [ 5233.278020] *** DEADLOCK *** [ 5233.281793] May be due to missing lock nesting notation [ 5233.286195] 3 locks held by kworker/u192:6/2413: [ 5233.289192] #0: ffff888111632548 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: process_one_work+0x5cc/0x6e0 [ 5233.294569] #1: ffffc9000e2a7e40 ((work_completion)(&queue->release_work)){+.+.}-{0:0}, at: process_one_work+0x1c5/0x6e0 [ 5233.300128] #2: ffffffff82d7dc40 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x62/0x530 [ 5233.304290] stack backtrace: [ 5233.306520] CPU: 4 UID: 0 PID: 2413 Comm: kworker/u192:6 Tainted: G O N 7.0.0-rc3nvme+ #20 PREEMPT(full) [ 5233.306524] Tainted: [O]=OOT_MODULE, [N]=TEST [ 5233.306525] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014 [ 5233.306527] Workqueue: nvmet-wq nvmet_tcp_release_queue_work [nvmet_tcp] [ 5233.306532] Call Trace: [ 5233.306534] <TASK> [ 5233.306536] dump_stack_lvl+0x73/0xb0 [ 5233.306552] print_deadlock_bug+0x225/0x2f0 [ 5233.306556] __lock_acquire+0x13f0/0x2290 [ 5233.306563] lock_acquire+0xd0/0x300 [ 5233.306565] ? touch_wq_lockdep_map+0x26/0x90 [ 5233.306571] ? __flush_work+0x20b/0x530 [ 5233.306573] ? touch_wq_lockdep_map+0x26/0x90 [ 5233.306577] touch_wq_lockdep_map+0x3b/0x90 [ 5233.306580] ? touch_wq_lockdep_map+0x26/0x90 [ 52 ---truncated---
Impacted products
Vendor Product Version
Linux Linux Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5
Version: 3976dd677e891c0b2c63d08028d445663539472c
Version: 4.9.68   
Create a notification for this product.
Show details on NVD website


{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/nvme/target/core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "ae5b0cad163833e10b271e9becc05d81dae56e5f",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "lessThan": "8d66ba89480ff098a58d79003a505f383aa4e920",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "lessThan": "a696fbbd5240b4ac9b166f7bd4c550882ff543f1",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "lessThan": "9a4d7222c0955b221e38bb66d10e6bccb672c8a1",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "lessThan": "ee6e20c4bc9eae542a0954a368449532383169d4",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "lessThan": "781f47d641432c26c19625b2cdd7f40825097592",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "lessThan": "551f445a56a11a6457550cddcf39c9ebb8bcacc6",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "lessThan": "aade8abd8b868b6ffa9697aadaea28ec7f65bee6",
              "status": "affected",
              "version": "06406d81a2d7cfb8abcc4fa6cdfeb8e5897007c5",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3976dd677e891c0b2c63d08028d445663539472c",
              "versionType": "git"
            },
            {
              "lessThan": "4.10",
              "status": "affected",
              "version": "4.9.68",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/nvme/target/core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.10"
            },
            {
              "lessThan": "4.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.258",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.209",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.175",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.140",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.88",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.30",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.258",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.209",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.175",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.140",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.88",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.30",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.7",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1",
                  "versionStartIncluding": "4.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.9.68",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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-\u003easync_event_work on\nthe same nvmet-wq.\n\nCall chain:\n\n nvmet_tcp_schedule_release_queue()\n   kref_put(\u0026queue-\u003ekref, nvmet_tcp_release_queue)\n     nvmet_tcp_release_queue()\n       queue_work(nvmet_wq, \u0026queue-\u003erelease_work) \u003c--- nvmet_wq\n         process_one_work()\n           nvmet_tcp_release_queue_work()\n             nvmet_cq_put(\u0026queue-\u003envme_cq)\n               nvmet_cq_destroy()\n                 nvmet_ctrl_put(cq-\u003ectrl)\n                   nvmet_ctrl_free()\n                     flush_work(\u0026ctrl-\u003easync_event_work) \u003c--- nvmet_wq\n\n                      Previously Scheduled by :-\n\t\t        nvmet_add_async_event\n\t\t          queue_work(nvmet_wq, \u0026ctrl-\u003easync_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)(\u0026queue-\u003erelease_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]  \u003cTASK\u003e\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---"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The bug is reached through the NVMe-oF TCP target (nvmet-tcp) disconnect/teardown path; remote peers connect over TCP and closing that connection drives `nvmet_tcp_release_queue_work()` on `nvmet-wq`, which can call the vulnerable `flush_work()` in `nvmet_ctrl_free()`.\nAC:L - An attacker fully controls both sides of the race by connecting, issuing an Async Event Request (which queues `async_event_work` on `nvmet-wq`), and then disconnecting to force controller teardown on the same workqueue.\nPR:N - Exploitation requires only network reachability to an exposed nvmet-tcp port; the discovery subsystem accepts any host NQN without Linux credentials, and no CAP_SYS_ADMIN or other local privileges are needed on the target.\nUI:N - The deadlock is triggered entirely through automated NVMe-oF protocol interaction (connect, admin command, disconnect) with no action required from a local user or administrator.\nS:U - Impact is confined to the kernel NVMe target subsystem (workqueue worker hang and nvmet service disruption); it does not cross a VM, container, or IOMMU security boundary.\nC:N - This is a recursive workqueue flush deadlock, not memory corruption; there is no out-of-bounds access, use-after-free, or information disclosure primitive.\nI:N - The flaw causes a worker to block during teardown but does not modify arbitrary kernel or user data and provides no write or code-execution primitive.\nA:H - Calling `flush_work()` on `nvmet-wq` from `nvmet_tcp_release_queue_work()` running on the same workqueue can permanently hang an nvmet worker (lockdep reports \"DEADLOCK\"), denying NVMe target service and stalling further nvmet workqueue processing."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:31:07.655Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/ae5b0cad163833e10b271e9becc05d81dae56e5f"
        },
        {
          "url": "https://git.kernel.org/stable/c/8d66ba89480ff098a58d79003a505f383aa4e920"
        },
        {
          "url": "https://git.kernel.org/stable/c/a696fbbd5240b4ac9b166f7bd4c550882ff543f1"
        },
        {
          "url": "https://git.kernel.org/stable/c/9a4d7222c0955b221e38bb66d10e6bccb672c8a1"
        },
        {
          "url": "https://git.kernel.org/stable/c/ee6e20c4bc9eae542a0954a368449532383169d4"
        },
        {
          "url": "https://git.kernel.org/stable/c/781f47d641432c26c19625b2cdd7f40825097592"
        },
        {
          "url": "https://git.kernel.org/stable/c/551f445a56a11a6457550cddcf39c9ebb8bcacc6"
        },
        {
          "url": "https://git.kernel.org/stable/c/aade8abd8b868b6ffa9697aadaea28ec7f65bee6"
        }
      ],
      "title": "nvmet: avoid recursive nvmet-wq flush in nvmet_ctrl_free",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-46304",
    "datePublished": "2026-06-08T15:46:31.747Z",
    "dateReserved": "2026-05-13T15:03:33.111Z",
    "dateUpdated": "2026-08-05T12:31:07.655Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.


Loading…

Loading…