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

s390/pai: Handle multiple PMU stop callback invocations

Handle the following scenario:
The kernel protects itself against a very high sampling load and
throttles the sampling using:

perf_event_throttle() --> PMU->stop()

Shortly later the scheduler may terminate the task and removes it from the
CPU. It again calls

PMU->stop()

which results in two invocations of PMU->stop() called back to back.
Protect against this and check the PERF_HES_STOPPED bit on function
entry. If it is already set return.
Clear bit PERF_HES_STOPPED in PMU->start().

Prohibit ioctl(fd, PERF_EVENT_IOC_PERIOD, ...) call for this event.
It sets perf_event::event_limit to a positive value and causes
perf_event_overflow() to invoke pai_stop() call back function when
perf_event::event_limit hits zero. This is not supported because the
sample events CRYPTO_ALL and NNPA_ALL are only taken at schedule out
of a task.

Use list_for_each_entry_safe() for safe iteration over syswide_list
in pai_have_samples().
Published: 2026-10-28
Score: n/a
EPSS: n/a
KEV: No
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

No advisories yet.

History

Wed, 28 Oct 2026 12:30:00 +0000

Type Values Removed Values Added
First Time appeared Linux linux
Vendors & Products Linux linux

Wed, 28 Oct 2026 12:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-665

Wed, 28 Oct 2026 10:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: s390/pai: Handle multiple PMU stop callback invocations Handle the following scenario: The kernel protects itself against a very high sampling load and throttles the sampling using: perf_event_throttle() --> PMU->stop() Shortly later the scheduler may terminate the task and removes it from the CPU. It again calls PMU->stop() which results in two invocations of PMU->stop() called back to back. Protect against this and check the PERF_HES_STOPPED bit on function entry. If it is already set return. Clear bit PERF_HES_STOPPED in PMU->start(). Prohibit ioctl(fd, PERF_EVENT_IOC_PERIOD, ...) call for this event. It sets perf_event::event_limit to a positive value and causes perf_event_overflow() to invoke pai_stop() call back function when perf_event::event_limit hits zero. This is not supported because the sample events CRYPTO_ALL and NNPA_ALL are only taken at schedule out of a task. Use list_for_each_entry_safe() for safe iteration over syswide_list in pai_have_samples().
Title s390/pai: Handle multiple PMU stop callback invocations
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-28T10:34:40.025Z

Reserved: 2026-09-25T10:25:14.393Z

Link: CVE-2026-99125

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-28T11:17:32.210

Modified: 2026-10-28T11:17:32.210

Link: CVE-2026-99125

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-28T12:15:14Z

Weaknesses