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

coredump: hold RCU while releasing parked threads

coredump_finish() releases the parked threads by clearing ->task in
their core_thread entry and calling wake_up_process() on each of them.
It does that without holding a reference on the task and without being
inside rcu.

But calling wake_up_process(task) without rcu here isn't safe. A parked
thread doesn't need that wakeup to leave. A spurious wakeup or a
preemption after the store is enough for the task to go away.

So if the coredump client is preempted between the store and
wake_up_process() the thread can exit and be freed in the meantime and
try_to_wake_up() takes pi_lock in freed memory.

Hold rcu across the loop.
Published: 2026-11-02
Score: 7 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Mon, 02 Nov 2026 16:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: coredump: hold RCU while releasing parked threads coredump_finish() releases the parked threads by clearing ->task in their core_thread entry and calling wake_up_process() on each of them. It does that without holding a reference on the task and without being inside rcu. But calling wake_up_process(task) without rcu here isn't safe. A parked thread doesn't need that wakeup to leave. A spurious wakeup or a preemption after the store is enough for the task to go away. So if the coredump client is preempted between the store and wake_up_process() the thread can exit and be freed in the meantime and try_to_wake_up() takes pi_lock in freed memory. Hold rcu across the loop.
Title coredump: hold RCU while releasing parked threads
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Metrics cvssV3_1

{'score': 7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-11-02T16:06:31.088Z

Reserved: 2026-09-25T10:25:14.401Z

Link: CVE-2026-99218

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-11-02T16:17:45.740

Modified: 2026-11-02T16:17:45.740

Link: CVE-2026-99218

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.