CVE-2024-43869

Technical Description

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

perf: Fix event leak upon exec and file release

The perf pending task work is never waited upon the matching event

release. In the case of a child event, released via free_event()

directly, this can potentially result in a leaked event, such as in the

following scenario that doesn't even require a weak IRQ work

implementation to trigger:

schedule()

prepare_task_switch()

=======> <NMI>

perf_event_overflow()

event->pending_sigtrap = ...

irq_work_queue(&event->pending_irq)

<======= </NMI>

perf_event_task_sched_out()

event_sched_out()

event->pending_sigtrap = 0;

atomic_long_inc_not_zero(&event->refcount)

task_work_add(&event->pending_task)

finish_lock_switch()

=======> <IRQ>

perf_pending_irq()

//do nothing, rely on pending task work

<======= </IRQ>

begin_new_exec()

perf_event_exit_task()

perf_event_exit_event()

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. 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.

Affected Products

References