CVE-2025-21657

5.5 MEDIUM
Published: January 21, 2025 Modified: October 15, 2025

Description

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Replace rq_lock() to raw_spin_rq_lock() in scx_ops_bypass() scx_ops_bypass() iterates all CPUs to re-enqueue all the scx tasks. For each CPU, it acquires a lock using rq_lock() regardless of whether a CPU is offline or the CPU is currently running a task in a higher scheduler class (e.g., deadline). The rq_lock() is supposed to be used for online CPUs, and the use of rq_lock() may trigger an unnecessary warning in rq_pin_lock(). Therefore, replace rq_lock() to raw_spin_rq_lock() in scx_ops_bypass(). Without this change, we observe the following warning: ===== START ===== [ 6.615205] rq->balance_callback && rq->balance_callback != &balance_push_callback [ 6.615208] WARNING: CPU: 2 PID: 0 at kernel/sched/sched.h:1730 __schedule+0x1130/0x1c90 ===== END =====

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://git.kernel.org/stable/c/6268d5bc10354fc2ab8d44a0cd3b042d49a0417e
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/d9e446dd63cee7161717a6a8414ba9c6435af764
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch

2 reference(s) from NVD

Quick Stats

CVSS v3 Score
5.5 / 10.0
EPSS (Exploit Probability)
0.0%
11th percentile
Exploitation Status
Not in CISA KEV

Affected Vendors

linux