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+0xd0/0x1a0
[ 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 + 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] <TASK>
[ 1236.609545] __dump_stack+0x21/0x60
[ 1236.609562] dump_stack_lvl+0xc2/0x100
[ 1236.609573] print_address_description+0x77/0x200
[ 1236.609587] ? ib_cq_poll_work+0xd0/0x1a0
[ 1236.609597] print_report+0x58/0x70
[ 1236.609607] kasan_report+0x117/0x150
[ 1236.609623] ? ib_cq_poll_work+0xd0/0x1a0
[ 1236.609636] ? process_scheduled_works+0x954/0x1600
[ 1236.609650] ib_cq_poll_work+0xd0/0x1a0
[ 1236.609662] ? process_scheduled_works+0x954/0x1600
[ 1236.609674] process_scheduled_works+0xc22/0x1600
[ 1236.609698] ? __pfx_process_scheduled_works+0x10/0x10
[ 1236.609713] ? __pfx_assign_work+0x10/0x10
[ 1236.609726] ? lock_is_held_type+0x7b/0x110
[ 1236.609741] worker_thread+0x975/0xee0
[ 1236.609757] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 1236.609775] ? __kthread_parkme+0x21e/0x260
[ 1236.609789] kthread+0x3a6/0x490
[ 1236.609800] ? __pfx_worker_thread+0x10/0x10
[ 1236.609809] ? __pfx_kthread+0x10/0x10
[ 1236.609820] ret_from_fork+0x55a/0xa20
[ 1236.609835] ? __pfx_ret_from_fork+0x10/0x10
[ 1236.609850] ? __pfx_kthread+0x10/0x10
[ 1236.609861] ret_from_fork_asm+0x1a/0x30
[ 1236.609880] </TASK>
[ 1236.609886]
[ 1236.661292] Allocated by task 5076:
[ 1236.662640] kasan_save_track+0x3e/0x80
[ 1236.663842] __kasan_kmalloc+0x72/0x90
[ 1236.664763] __kmalloc_noprof+0x2b0/0x5d0
[ 1236.665356] __ib_alloc_cq+0x284/0x1000
[ 1236.666573] __ib_alloc_cq_any+0x23e/0x340
[ 1236.668654] smbdirect_connection_create_qp+0x6f7/0x1070
[ 1236.669757] smbdirect_accept_connect_request+0x500/0x1ca0
[ 1236.672625] smbdirect_listen_rdma_event_handler+0x1655/0x1c50
[ 1236.673930] cma_listen_handler+0x1bf/0x260
[ 1236.674923] cma_cm_event_handler+0x128/0x380
[ 1236.676926] cma_ib_req_handler+0x2d3d/0x4de0
[ 1236.678368] cm_process_work+0xb0/0x530
[ 1236.680454] cm_queue_work_unlock+0xb1/0x230
[ 1236.681673] cm_work_handler+0x969f/0xdca0
[ 1236.682704] process_scheduled_works+0xc22/0x1600
[ 1236.683447] worker_thread+0x975/0xee0
[ 1236.685901] kthread+0x3a6/0x490
[ 1236.688164] ret_from_fork+0x55a/0xa20
[ 1236.689522] ret_from_fork_asm+0x1a/0x30
[ 1236.690073]
[ 1236.690378] Freed by task 5137:
[ 1236.692242] kasan_save_track+0x3e/0x80
[ 1236.694272] kasan_save_free_info+0x40/0x50
[ 1236.695514] __kasan_slab_free+0x3a/0x60
[ 1236.696773] kfree+0x14e/0x4e0
[ 1236.697216] ib_destroy_cq_user+0x18d/0x250
[ 1236.699817] smbdirect_connection_destroy_qp+0xf2/0x280
[ 1236.702115] smbdirect_socket_destroy_sync+0x1607/0x2720
[ 1236.704062] smbdirect_socket_release+0x140/0x280
[ 1236.705286] smb_direct_free_transpor
---truncated---

Project Subscriptions

Vendors Products
Linux Kernel Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Thu, 17 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
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+0xd0/0x1a0 [ 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 + 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] <TASK> [ 1236.609545] __dump_stack+0x21/0x60 [ 1236.609562] dump_stack_lvl+0xc2/0x100 [ 1236.609573] print_address_description+0x77/0x200 [ 1236.609587] ? ib_cq_poll_work+0xd0/0x1a0 [ 1236.609597] print_report+0x58/0x70 [ 1236.609607] kasan_report+0x117/0x150 [ 1236.609623] ? ib_cq_poll_work+0xd0/0x1a0 [ 1236.609636] ? process_scheduled_works+0x954/0x1600 [ 1236.609650] ib_cq_poll_work+0xd0/0x1a0 [ 1236.609662] ? process_scheduled_works+0x954/0x1600 [ 1236.609674] process_scheduled_works+0xc22/0x1600 [ 1236.609698] ? __pfx_process_scheduled_works+0x10/0x10 [ 1236.609713] ? __pfx_assign_work+0x10/0x10 [ 1236.609726] ? lock_is_held_type+0x7b/0x110 [ 1236.609741] worker_thread+0x975/0xee0 [ 1236.609757] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 1236.609775] ? __kthread_parkme+0x21e/0x260 [ 1236.609789] kthread+0x3a6/0x490 [ 1236.609800] ? __pfx_worker_thread+0x10/0x10 [ 1236.609809] ? __pfx_kthread+0x10/0x10 [ 1236.609820] ret_from_fork+0x55a/0xa20 [ 1236.609835] ? __pfx_ret_from_fork+0x10/0x10 [ 1236.609850] ? __pfx_kthread+0x10/0x10 [ 1236.609861] ret_from_fork_asm+0x1a/0x30 [ 1236.609880] </TASK> [ 1236.609886] [ 1236.661292] Allocated by task 5076: [ 1236.662640] kasan_save_track+0x3e/0x80 [ 1236.663842] __kasan_kmalloc+0x72/0x90 [ 1236.664763] __kmalloc_noprof+0x2b0/0x5d0 [ 1236.665356] __ib_alloc_cq+0x284/0x1000 [ 1236.666573] __ib_alloc_cq_any+0x23e/0x340 [ 1236.668654] smbdirect_connection_create_qp+0x6f7/0x1070 [ 1236.669757] smbdirect_accept_connect_request+0x500/0x1ca0 [ 1236.672625] smbdirect_listen_rdma_event_handler+0x1655/0x1c50 [ 1236.673930] cma_listen_handler+0x1bf/0x260 [ 1236.674923] cma_cm_event_handler+0x128/0x380 [ 1236.676926] cma_ib_req_handler+0x2d3d/0x4de0 [ 1236.678368] cm_process_work+0xb0/0x530 [ 1236.680454] cm_queue_work_unlock+0xb1/0x230 [ 1236.681673] cm_work_handler+0x969f/0xdca0 [ 1236.682704] process_scheduled_works+0xc22/0x1600 [ 1236.683447] worker_thread+0x975/0xee0 [ 1236.685901] kthread+0x3a6/0x490 [ 1236.688164] ret_from_fork+0x55a/0xa20 [ 1236.689522] ret_from_fork_asm+0x1a/0x30 [ 1236.690073] [ 1236.690378] Freed by task 5137: [ 1236.692242] kasan_save_track+0x3e/0x80 [ 1236.694272] kasan_save_free_info+0x40/0x50 [ 1236.695514] __kasan_slab_free+0x3a/0x60 [ 1236.696773] kfree+0x14e/0x4e0 [ 1236.697216] ib_destroy_cq_user+0x18d/0x250 [ 1236.699817] smbdirect_connection_destroy_qp+0xf2/0x280 [ 1236.702115] smbdirect_socket_destroy_sync+0x1607/0x2720 [ 1236.704062] smbdirect_socket_release+0x140/0x280 [ 1236.705286] smb_direct_free_transpor ---truncated---
Title smb: smbdirect: free completion queues with ib_free_cq()
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-09-17T16:07:00.463Z

Reserved: 2026-09-11T19:38:34.791Z

Link: CVE-2026-90173

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-17T17:17:10.953

Modified: 2026-09-17T17:17:10.953

Link: CVE-2026-90173

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.