{
  "cveId": "CVE-2026-90173",
  "url": "https://patchblox.com/security/cve/CVE-2026-90173",
  "summary": "CVE-2026-90173 is fixed in linux on 1 platform by DEBIAN-CVE-2026-90173 (version 7.2.6-1), released September 23, 2026. It is not reported as exploited. Patch Radar priority: Urgent.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  smb: smbdirect: free completion queues with ib_f...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  smb: smbdirect: free completion queues with ib_free_cq()  smbdirect_connection_destroy_qp() creates the send and receive completion queues with ib_alloc_cq_any(), which for IB_POLL_WORKQUEUE arms an internal completion handler that runs ib_cq_poll_work() on a workqueue. Tearing those CQs down with ib_destroy_cq() frees them without first cancelling that poll work.  If the provider posts a completion late -- for example Soft-RoCE (rxe) posting an RNR error from rxe_receiver() after rdma_destroy_qp() -- the handler re-queues ib_cq_poll_work() on the already-freed CQ, and a follow-on access faults in rxe_req_notify_cq().  Use ib_free_cq(), which cancel_work_sync()es the poll work before freeing the CQ, so no completion handler can run against a freed queue.  [ 1236.599526] ================================================================== [ 1236.602142] BUG: KASAN: slab-use-after-free in ib_cq_poll_work\u002B0xd0/0x1a0 [ 1236.605524] Read of size 8 at addr ffff888111865800 by task kworker/4:1H/82 [ 1236.609017] [ 1236.609270] CPU: 4 UID: 0 PID: 82 Comm: kworker/4:1H Not tainted 7.2.0-rc3-next-20260717-virtme #110 PREEMPT(lazy) [ 1236.609287] Hardware name: QEMU Standard PC (i440FX \u002B PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 [ 1236.609498] Workqueue: ib-comp-wq ib_cq_poll_work [ 1236.609525] Call Trace: [ 1236.609536]  \u003CTASK\u003E [ 1236.609545]  __dump_stack\u002B0x21/0x60 [ 1236.609562]  dump_stack_lvl\u002B0xc2/0x100 [ 1236.609573]  print_address_description\u002B0x77/0x200 [ 1236.609587]  ? ib_cq_poll_work\u002B0xd0/0x1a0 [ 1236.609597]  print_report\u002B0x58/0x70 [ 1236.609607]  kasan_report\u002B0x117/0x150 [ 1236.609623]  ? ib_cq_poll_work\u002B0xd0/0x1a0 [ 1236.609636]  ? process_scheduled_works\u002B0x954/0x1600 [ 1236.609650]  ib_cq_poll_work\u002B0xd0/0x1a0 [ 1236.609662]  ? process_scheduled_works\u002B0x954/0x1600 [ 1236.609674]  process_scheduled_works\u002B0xc22/0x1600 [ 1236.609698]  ? __pfx_process_scheduled_works\u002B0x10/0x10 [ 1236.609713]  ? __pfx_assign_work\u002B0x10/0x10 [ 1236.609726]  ? lock_is_held_type\u002B0x7b/0x110 [ 1236.609741]  worker_thread\u002B0x975/0xee0 [ 1236.609757]  ? __pfx_do_raw_spin_lock\u002B0x10/0x10 [ 1236.609775]  ? __kthread_parkme\u002B0x21e/0x260 [ 1236.609789]  kthread\u002B0x3a6/0x490 [ 1236.609800]  ? __pfx_worker_thread\u002B0x10/0x10 [ 1236.609809]  ? __pfx_kthread\u002B0x10/0x10 [ 1236.609820]  ret_from_fork\u002B0x55a/0xa20 [ 1236.609835]  ? __pfx_ret_from_fork\u002B0x10/0x10 [ 1236.609850]  ? __pfx_kthread\u002B0x10/0x10 [ 1236.609861]  ret_from_fork_asm\u002B0x1a/0x30 [ 1236.609880]  \u003C/TASK\u003E [ 1236.609886] [ 1236.661292] Allocated by task 5076: [ 1236.662640]  kasan_save_track\u002B0x3e/0x80 [ 1236.663842]  __kasan_kmalloc\u002B0x72/0x90 [ 1236.664763]  __kmalloc_noprof\u002B0x2b0/0x5d0 [ 1236.665356]  __ib_alloc_cq\u002B0x284/0x1000 [ 1236.666573]  __ib_alloc_cq_any\u002B0x23e/0x340 [ 1236.668654]  smbdirect_connection_create_qp\u002B0x6f7/0x1070 [ 1236.669757]  smbdirect_accept_connect_request\u002B0x500/0x1ca0 [ 1236.672625]  smbdirect_listen_rdma_event_handler\u002B0x1655/0x1c50 [ 1236.673930]  cma_listen_handler\u002B0x1bf/0x260 [ 1236.674923]  cma_cm_event_handler\u002B0x128/0x380 [ 1236.676926]  cma_ib_req_handler\u002B0x2d3d/0x4de0 [ 1236.678368]  cm_process_work\u002B0xb0/0x530 [ 1236.680454]  cm_queue_work_unlock\u002B0xb1/0x230 [ 1236.681673]  cm_work_handler\u002B0x969f/0xdca0 [ 1236.682704]  process_scheduled_works\u002B0xc22/0x1600 [ 1236.683447]  worker_thread\u002B0x975/0xee0 [ 1236.685901]  kthread\u002B0x3a6/0x490 [ 1236.688164]  ret_from_fork\u002B0x55a/0xa20 [ 1236.689522]  ret_from_fork_asm\u002B0x1a/0x30 [ 1236.690073] [ 1236.690378] Freed by task 5137: [ 1236.692242]  kasan_save_track\u002B0x3e/0x80 [ 1236.694272]  kasan_save_free_info\u002B0x40/0x50 [ 1236.695514]  __kasan_slab_free\u002B0x3a/0x60 [ 1236.696773]  kfree\u002B0x14e/0x4e0 [ 1236.697216]  ib_destroy_cq_user\u002B0x18d/0x250 [ 1236.699817]  smbdirect_connection_destroy_qp\u002B0xf2/0x280 [ 1236.702115]  smbdirect_socket_destroy_sync\u002B0x1607/0x2720 [ 1236.704062]  smbdirect_socket_release\u002B0x140/0x280 [ 1236.705286]  smb_direct_free_transpor ---truncated---",
  "published": "2026-09-17T17:17:10Z",
  "severity": "critical",
  "cvss": 9.8,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00553,
  "epssPercentile": 0.46438,
  "priority": "Urgent",
  "priorityTier": 2,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-90173",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-90173",
      "released": "2026-09-23T19:19:02Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T06:59:42Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}