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GHSA-RF5W-WP84-MH25

Vulnerability from github – Published: 2026-08-27 06:31 – Updated: 2026-08-27 06:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

block: stop the timeout timer when releasing a never added disk

disk_release() undoes blk_mq_init_allocated_queue() for a disk whose probe failed before add_disk(), but it only calls blk_mq_exit_queue(). Nothing there stops q->timeout, and that timer rolls forward: it stays pending until it next expires, not until the last request completes. So if the driver issued any I/O before adding the disk, the request_queue is freed while still linked into a timer wheel bucket.

Commit 6f8191fdf41d ("block: simplify disk shutdown") dropped the blk_cleanup_queue() call that used to stop it. __del_gendisk() and blk_mq_destroy_queue() still do; only the probe failure path lost it.

nvme gets there because nvme_update_ns_info() submits Report Zones or FDP io-mgmt-recv on ns->queue before the disk is added, so a later failure - a concurrent reset setting NVME_CTRL_FROZEN, or device_add_disk() failing - lands in put_disk() with the timer armed:

BUG: KASAN: slab-use-after-free in detach_if_pending+0x30c/0x340 Write of size 8 at addr ffff888004d71310 by task kworker/u8:2/37 __timer_delete_sync+0x156/0x240 kernel/time/timer.c:1621 blk_sync_queue+0x22/0x40 block/blk-core.c:222 nvme_sync_queues+0x100/0x150 drivers/nvme/host/core.c:5362 nvme_reset_work+0x138/0x930 drivers/nvme/host/pci.c:3264

Allocated by task 34: __blk_mq_alloc_disk+0x33/0x100 block/blk-mq.c:4462 nvme_alloc_ns+0x290/0x3870 drivers/nvme/host/core.c:4146

Freed by task 0: blk_free_queue_rcu+0x3a/0x50 block/blk-core.c:254 rcu_core+0xc10/0x1730 kernel/rcu/tree.c:2857

The queue being synced there is ctrl->admin_q, only a victim sharing a timer wheel bucket with the freed queue's dangling entry; other runs tripped in enqueue_timer(), __run_timers() or blk_mq_timeout_work(). Failing nvme_alloc_ns() with a debug patch makes it deterministic: one leaked timer trips KASAN within seconds, while 1987 patched releases produced no splat.

Stop the timer and the queue work items before blk_mq_exit_queue(), like blk_mq_destroy_queue() does.

Found by FuzzNvme.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-80589"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-26T15:17:15Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nblock: stop the timeout timer when releasing a never added disk\n\ndisk_release() undoes blk_mq_init_allocated_queue() for a disk whose\nprobe failed before add_disk(), but it only calls blk_mq_exit_queue().\nNothing there stops q-\u003etimeout, and that timer rolls forward: it stays\npending until it next expires, not until the last request completes.\nSo if the driver issued any I/O before adding the disk, the\nrequest_queue is freed while still linked into a timer wheel bucket.\n\nCommit 6f8191fdf41d (\"block: simplify disk shutdown\") dropped the\nblk_cleanup_queue() call that used to stop it.  __del_gendisk() and\nblk_mq_destroy_queue() still do; only the probe failure path lost it.\n\nnvme gets there because nvme_update_ns_info() submits Report Zones or\nFDP io-mgmt-recv on ns-\u003equeue before the disk is added, so a later\nfailure - a concurrent reset setting NVME_CTRL_FROZEN, or\ndevice_add_disk() failing - lands in put_disk() with the timer armed:\n\n  BUG: KASAN: slab-use-after-free in detach_if_pending+0x30c/0x340\n  Write of size 8 at addr ffff888004d71310 by task kworker/u8:2/37\n   __timer_delete_sync+0x156/0x240 kernel/time/timer.c:1621\n   blk_sync_queue+0x22/0x40 block/blk-core.c:222\n   nvme_sync_queues+0x100/0x150 drivers/nvme/host/core.c:5362\n   nvme_reset_work+0x138/0x930 drivers/nvme/host/pci.c:3264\n\n  Allocated by task 34:\n   __blk_mq_alloc_disk+0x33/0x100 block/blk-mq.c:4462\n   nvme_alloc_ns+0x290/0x3870 drivers/nvme/host/core.c:4146\n\n  Freed by task 0:\n   blk_free_queue_rcu+0x3a/0x50 block/blk-core.c:254\n   rcu_core+0xc10/0x1730 kernel/rcu/tree.c:2857\n\nThe queue being synced there is ctrl-\u003eadmin_q, only a victim sharing a\ntimer wheel bucket with the freed queue\u0027s dangling entry; other runs\ntripped in enqueue_timer(), __run_timers() or blk_mq_timeout_work().\nFailing nvme_alloc_ns() with a debug patch makes it deterministic: one\nleaked timer trips KASAN within seconds, while 1987 patched releases\nproduced no splat.\n\nStop the timer and the queue work items before blk_mq_exit_queue(), like\nblk_mq_destroy_queue() does.\n\nFound by FuzzNvme.",
  "id": "GHSA-rf5w-wp84-mh25",
  "modified": "2026-08-27T06:31:33Z",
  "published": "2026-08-27T06:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80589"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1a0ae4d502062a2759f2a92d12bdeab3c64c7372"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/26cb8ebbfaf713c82e142d08828d4d765057633b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6ae7364f68e6c7af6b6df4bbb14040b89e5975d0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6f06dbe5012c160e0dba418a5a9cb16c456ad46a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/93d620519d71dfc6ee64b5baea74f1d85d4439fb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bb03b56d1d754908a37a160603be21769da423cf"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}



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