CVE-2025-37747

/// Technical description

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

perf: Fix hang while freeing sigtrap event

Perf can hang while freeing a sigtrap event if a related deferred

signal hadn't managed to be sent before the file got closed:

perf_event_overflow()

task_work_add(perf_pending_task)

fput()

task_work_add(____fput())

task_work_run()

____fput()

perf_release()

perf_event_release_kernel()

_free_event()

perf_pending_task_sync()

task_work_cancel() -> FAILED

rcuwait_wait_event()

Once task_work_run() is running, the list of pending callbacks is

removed from the task_struct and from this point on task_work_cancel()

can't remove any pending and not yet started work items, hence the

task_work_cancel() failure and the hang on rcuwait_wait_event().

Task work could be changed to remove one work at a time, so a work

running on the current task can always cancel a pending on

/// 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