CVE-2025-21733

/// Technical description

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

tracing/osnoise: Fix resetting of tracepoints

If a timerlat tracer is started with the osnoise option OSNOISE_WORKLOAD

disabled, but then that option is enabled and timerlat is removed, the

tracepoints that were enabled on timerlat registration do not get

disabled. If the option is disabled again and timelat is started, then it

triggers a warning in the tracepoint code due to registering the

tracepoint again without ever disabling it.

Do not use the same user space defined options to know to disable the

tracepoints when timerlat is removed. Instead, set a global flag when it

is enabled and use that flag to know to disable the events.

~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options

~# echo timerlat > /sys/kernel/tracing/current_tracer

~# echo OSNOISE_WORKLOAD > /sys/kernel/tracing/osnoise/options

~# echo nop > /sys/kernel/tracing/current_tracer

~# echo NO_OSNOISE_WORKLOAD > /sys/kernel/tracing

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References