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

RDMA/iwcm: Fix use-after-free of work objects after cm_id destruction

The commit 59c68ac31e15 ("iw_cm: free cm_id resources on the last
deref") simplified cm_id resource management by freeing cm_id once all
references to the cm_id were removed. The references are removed either
upon completion of iw_cm event handlers or when the application destroys
the cm_id. This commit introduced the use-after-free condition where
cm_id_private object could still be in use by event handler works during
the destruction of cm_id. The commit aee2424246f9 ("RDMA/iwcm: Fix a
use-after-free related to destroying CM IDs") addressed this use-after-
free by flushing all pending works at the cm_id destruction.

However, still another use-after-free possibility remained. It happens
with the work objects allocated for each cm_id_priv within
alloc_work_entries() during cm_id creation, and subsequently freed in
dealloc_work_entries() once all references to the cm_id are removed.
If the cm_id's last reference is decremented in the event handler work,
the work object for the work itself gets removed, and causes the use-
after-free BUG below:

BUG: KASAN: slab-use-after-free in __pwq_activate_work+0x1ff/0x250
Read of size 8 at addr ffff88811f9cf800 by task kworker/u16:1/147091

CPU: 2 UID: 0 PID: 147091 Comm: kworker/u16:1 Not tainted 6.15.0-rc2+ #27 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014
Workqueue: 0x0 (iw_cm_wq)
Call Trace:
<TASK>
dump_stack_lvl+0x6a/0x90
print_report+0x174/0x554
? __virt_addr_valid+0x208/0x430
? __pwq_activate_work+0x1ff/0x250
kasan_report+0xae/0x170
? __pwq_activate_work+0x1ff/0x250
__pwq_activate_work+0x1ff/0x250
pwq_dec_nr_in_flight+0x8c5/0xfb0
process_one_work+0xc11/0x1460
? __pfx_process_one_work+0x10/0x10
? assign_work+0x16c/0x240
worker_thread+0x5ef/0xfd0
? __pfx_worker_thread+0x10/0x10
kthread+0x3b0/0x770
? __pfx_kthread+0x10/0x10
? rcu_is_watching+0x11/0xb0
? _raw_spin_unlock_irq+0x24/0x50
? rcu_is_watching+0x11/0xb0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x30/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>

Allocated by task 147416:
kasan_save_stack+0x2c/0x50
kasan_save_track+0x10/0x30
__kasan_kmalloc+0xa6/0xb0
alloc_work_entries+0xa9/0x260 [iw_cm]
iw_cm_connect+0x23/0x4a0 [iw_cm]
rdma_connect_locked+0xbfd/0x1920 [rdma_cm]
nvme_rdma_cm_handler+0x8e5/0x1b60 [nvme_rdma]
cma_cm_event_handler+0xae/0x320 [rdma_cm]
cma_work_handler+0x106/0x1b0 [rdma_cm]
process_one_work+0x84f/0x1460
worker_thread+0x5ef/0xfd0
kthread+0x3b0/0x770
ret_from_fork+0x30/0x70
ret_from_fork_asm+0x1a/0x30

Freed by task 147091:
kasan_save_stack+0x2c/0x50
kasan_save_track+0x10/0x30
kasan_save_free_info+0x37/0x60
__kasan_slab_free+0x4b/0x70
kfree+0x13a/0x4b0
dealloc_work_entries+0x125/0x1f0 [iw_cm]
iwcm_deref_id+0x6f/0xa0 [iw_cm]
cm_work_handler+0x136/0x1ba0 [iw_cm]
process_one_work+0x84f/0x1460
worker_thread+0x5ef/0xfd0
kthread+0x3b0/0x770
ret_from_fork+0x30/0x70
ret_from_fork_asm+0x1a/0x30

Last potentially related work creation:
kasan_save_stack+0x2c/0x50
kasan_record_aux_stack+0xa3/0xb0
__queue_work+0x2ff/0x1390
queue_work_on+0x67/0xc0
cm_event_handler+0x46a/0x820 [iw_cm]
siw_cm_upcall+0x330/0x650 [siw]
siw_cm_work_handler+0x6b9/0x2b20 [siw]
process_one_work+0x84f/0x1460
worker_thread+0x5ef/0xfd0
kthread+0x3b0/0x770
ret_from_fork+0x30/0x70
ret_from_fork_asm+0x1a/0x30

This BUG is reproducible by repeating the blktests test case nvme/061
for the rdma transport and the siw driver.

To avoid the use-after-free of cm_id_private work objects, ensure that
the last reference to the cm_id is decremented not in the event handler
works, but in the cm_id destruction context. For that purpose, mo
---truncated---
Published: 2025-07-04
Score: 7.8 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories
Source ID Title
Debian DLA Debian DLA DLA-4327-1 linux security update
Debian DLA Debian DLA DLA-4328-1 linux-6.1 security update
Debian DSA Debian DSA DSA-5973-1 linux security update
EUVD EUVD EUVD-2025-20045 In the Linux kernel, the following vulnerability has been resolved: RDMA/iwcm: Fix use-after-free of work objects after cm_id destruction The commit 59c68ac31e15 ("iw_cm: free cm_id resources on the last deref") simplified cm_id resource management by freeing cm_id once all references to the cm_id were removed. The references are removed either upon completion of iw_cm event handlers or when the application destroys the cm_id. This commit introduced the use-after-free condition where cm_id_private object could still be in use by event handler works during the destruction of cm_id. The commit aee2424246f9 ("RDMA/iwcm: Fix a use-after-free related to destroying CM IDs") addressed this use-after- free by flushing all pending works at the cm_id destruction. However, still another use-after-free possibility remained. It happens with the work objects allocated for each cm_id_priv within alloc_work_entries() during cm_id creation, and subsequently freed in dealloc_work_entries() once all references to the cm_id are removed. If the cm_id's last reference is decremented in the event handler work, the work object for the work itself gets removed, and causes the use- after-free BUG below: BUG: KASAN: slab-use-after-free in __pwq_activate_work+0x1ff/0x250 Read of size 8 at addr ffff88811f9cf800 by task kworker/u16:1/147091 CPU: 2 UID: 0 PID: 147091 Comm: kworker/u16:1 Not tainted 6.15.0-rc2+ #27 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 Workqueue: 0x0 (iw_cm_wq) Call Trace: <TASK> dump_stack_lvl+0x6a/0x90 print_report+0x174/0x554 ? __virt_addr_valid+0x208/0x430 ? __pwq_activate_work+0x1ff/0x250 kasan_report+0xae/0x170 ? __pwq_activate_work+0x1ff/0x250 __pwq_activate_work+0x1ff/0x250 pwq_dec_nr_in_flight+0x8c5/0xfb0 process_one_work+0xc11/0x1460 ? __pfx_process_one_work+0x10/0x10 ? assign_work+0x16c/0x240 worker_thread+0x5ef/0xfd0 ? __pfx_worker_thread+0x10/0x10 kthread+0x3b0/0x770 ? __pfx_kthread+0x10/0x10 ? rcu_is_watching+0x11/0xb0 ? _raw_spin_unlock_irq+0x24/0x50 ? rcu_is_watching+0x11/0xb0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x30/0x70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 147416: kasan_save_stack+0x2c/0x50 kasan_save_track+0x10/0x30 __kasan_kmalloc+0xa6/0xb0 alloc_work_entries+0xa9/0x260 [iw_cm] iw_cm_connect+0x23/0x4a0 [iw_cm] rdma_connect_locked+0xbfd/0x1920 [rdma_cm] nvme_rdma_cm_handler+0x8e5/0x1b60 [nvme_rdma] cma_cm_event_handler+0xae/0x320 [rdma_cm] cma_work_handler+0x106/0x1b0 [rdma_cm] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 Freed by task 147091: kasan_save_stack+0x2c/0x50 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x60 __kasan_slab_free+0x4b/0x70 kfree+0x13a/0x4b0 dealloc_work_entries+0x125/0x1f0 [iw_cm] iwcm_deref_id+0x6f/0xa0 [iw_cm] cm_work_handler+0x136/0x1ba0 [iw_cm] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 Last potentially related work creation: kasan_save_stack+0x2c/0x50 kasan_record_aux_stack+0xa3/0xb0 __queue_work+0x2ff/0x1390 queue_work_on+0x67/0xc0 cm_event_handler+0x46a/0x820 [iw_cm] siw_cm_upcall+0x330/0x650 [siw] siw_cm_work_handler+0x6b9/0x2b20 [siw] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 This BUG is reproducible by repeating the blktests test case nvme/061 for the rdma transport and the siw driver. To avoid the use-after-free of cm_id_private work objects, ensure that the last reference to the cm_id is decremented not in the event handler works, but in the cm_id destruction context. For that purpose, mo ---truncated---
Ubuntu USN Ubuntu USN USN-7774-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7774-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7774-3 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7775-1 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7775-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7776-1 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-7775-3 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7774-4 Linux kernel (KVM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7774-5 Linux kernel (NVIDIA Tegra IGX) vulnerabilities
Ubuntu USN Ubuntu USN USN-7833-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7834-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7833-2 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7833-3 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7833-4 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7856-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-2 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-8031-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-3 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-4 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-5 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8031-2 Linux kernel (GCP FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-6 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-8031-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-8052-1 Linux kernel (Low Latency) vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-7 Linux kernel (Low Latency NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-8028-8 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-8052-2 Linux kernel (Xilinx) vulnerabilities
Ubuntu USN Ubuntu USN USN-8074-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-8074-2 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-8126-1 Linux kernel (Azure) vulnerabilities
History

Thu, 18 Dec 2025 21:15:00 +0000

Type Values Removed Values Added
First Time appeared Debian
Debian debian Linux
Weaknesses CWE-416
CPEs cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Debian
Debian debian Linux
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Mon, 03 Nov 2025 18:30:00 +0000


Thu, 17 Jul 2025 17:15:00 +0000


Mon, 07 Jul 2025 12:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Fri, 04 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: RDMA/iwcm: Fix use-after-free of work objects after cm_id destruction The commit 59c68ac31e15 ("iw_cm: free cm_id resources on the last deref") simplified cm_id resource management by freeing cm_id once all references to the cm_id were removed. The references are removed either upon completion of iw_cm event handlers or when the application destroys the cm_id. This commit introduced the use-after-free condition where cm_id_private object could still be in use by event handler works during the destruction of cm_id. The commit aee2424246f9 ("RDMA/iwcm: Fix a use-after-free related to destroying CM IDs") addressed this use-after- free by flushing all pending works at the cm_id destruction. However, still another use-after-free possibility remained. It happens with the work objects allocated for each cm_id_priv within alloc_work_entries() during cm_id creation, and subsequently freed in dealloc_work_entries() once all references to the cm_id are removed. If the cm_id's last reference is decremented in the event handler work, the work object for the work itself gets removed, and causes the use- after-free BUG below: BUG: KASAN: slab-use-after-free in __pwq_activate_work+0x1ff/0x250 Read of size 8 at addr ffff88811f9cf800 by task kworker/u16:1/147091 CPU: 2 UID: 0 PID: 147091 Comm: kworker/u16:1 Not tainted 6.15.0-rc2+ #27 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 Workqueue: 0x0 (iw_cm_wq) Call Trace: <TASK> dump_stack_lvl+0x6a/0x90 print_report+0x174/0x554 ? __virt_addr_valid+0x208/0x430 ? __pwq_activate_work+0x1ff/0x250 kasan_report+0xae/0x170 ? __pwq_activate_work+0x1ff/0x250 __pwq_activate_work+0x1ff/0x250 pwq_dec_nr_in_flight+0x8c5/0xfb0 process_one_work+0xc11/0x1460 ? __pfx_process_one_work+0x10/0x10 ? assign_work+0x16c/0x240 worker_thread+0x5ef/0xfd0 ? __pfx_worker_thread+0x10/0x10 kthread+0x3b0/0x770 ? __pfx_kthread+0x10/0x10 ? rcu_is_watching+0x11/0xb0 ? _raw_spin_unlock_irq+0x24/0x50 ? rcu_is_watching+0x11/0xb0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x30/0x70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 147416: kasan_save_stack+0x2c/0x50 kasan_save_track+0x10/0x30 __kasan_kmalloc+0xa6/0xb0 alloc_work_entries+0xa9/0x260 [iw_cm] iw_cm_connect+0x23/0x4a0 [iw_cm] rdma_connect_locked+0xbfd/0x1920 [rdma_cm] nvme_rdma_cm_handler+0x8e5/0x1b60 [nvme_rdma] cma_cm_event_handler+0xae/0x320 [rdma_cm] cma_work_handler+0x106/0x1b0 [rdma_cm] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 Freed by task 147091: kasan_save_stack+0x2c/0x50 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x60 __kasan_slab_free+0x4b/0x70 kfree+0x13a/0x4b0 dealloc_work_entries+0x125/0x1f0 [iw_cm] iwcm_deref_id+0x6f/0xa0 [iw_cm] cm_work_handler+0x136/0x1ba0 [iw_cm] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 Last potentially related work creation: kasan_save_stack+0x2c/0x50 kasan_record_aux_stack+0xa3/0xb0 __queue_work+0x2ff/0x1390 queue_work_on+0x67/0xc0 cm_event_handler+0x46a/0x820 [iw_cm] siw_cm_upcall+0x330/0x650 [siw] siw_cm_work_handler+0x6b9/0x2b20 [siw] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 This BUG is reproducible by repeating the blktests test case nvme/061 for the rdma transport and the siw driver. To avoid the use-after-free of cm_id_private work objects, ensure that the last reference to the cm_id is decremented not in the event handler works, but in the cm_id destruction context. For that purpose, mo ---truncated---
Title RDMA/iwcm: Fix use-after-free of work objects after cm_id destruction
References

Subscriptions

Debian Debian Linux
Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-05-11T21:23:24.277Z

Reserved: 2025-04-16T04:51:23.994Z

Link: CVE-2025-38211

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2025-07-04T14:15:29.337

Modified: 2025-12-18T21:12:10.963

Link: CVE-2025-38211

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-07-04T00:00:00Z

Links: CVE-2025-38211 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-07-13T21:47:54Z

Weaknesses