CVE-2026-97961perf/core: Allow list_del during perf_event_overflow()

Official description

In the Linux kernel, the following vulnerability has been resolved: perf/core: Allow list_del during perf_event_overflow() A PMU might use perf_sched_cb_inc() and perf_sched_cb_dec() interface to get the PMU call back function pmu::sched_task invoked at schedule in and schedule out. This is achieved by walking along the list anchored by sched_cb_list. The following scenario might lead to a list corruption. perf_pmu_sched_task() for_each_list_entry(..., &sched_cb_list) +--> __perf_pmu_sched_task() +--> event->pmu->sched_task()) +--> PMU_push_sample() +--> perf_event_overflow() +--> __perf_event_overflow() +--> pmu->stop() +--> perf_sched_cb_dec() remove entry from sched_cb_list while list node in use. This happens when ioctl(fd, PERF_EVENT_IOC_REFRESH, xxx) has been invoked and perf_event::event_limit hits zero. Prevent the list corruption and convert for_each_list_entry() to for_each_list_entry_safe().

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/fa360a018369f3eb4fe4f4792238adfc1f6fd5dc
• https://git.kernel.org/stable/c/723e85fb2c3bcd237ac02cbd69502ed62ce0068c
• https://git.kernel.org/stable/c/6d0b9ce3be221c9077653f3670d60d66bb725ee2
• https://git.kernel.org/stable/c/e2770c76a02452fddb52e9e05c7ed6acfef06c32
• https://git.kernel.org/stable/c/59e63416f5153e7d58652c616fbdcb7d5e01fff7