In the Linux kernel, the following vulnerability has been resolved: perf: Fix race between perf_event_exit_task() and perf_pending_task() A race… (CVE-2026-98790)

This vulnerability in the Linux kernel's perf subsystem arises from a race condition between perf_event_exit_task() and perf_pending_task() during the execution of begin_new_exec(). Specifically, perf_event_exit_task() may be called while the PF_EXITING flag is not set, allowing perf_sigtrap() to continue and trigger WARN_ON_ONCE(event->ctx->task != current). Both task exit and exec paths can call perf_event_exit_task(), which sets ctx->task to TASK_TOMBSTONE. The fix explicitly checks if event->ctx->task equals TASK_TOMBSTONE, removing the redundant PF_EXITING check and preventing the race condition.

The race condition could lead to improper execution flow in the perf subsystem, potentially causing kernel warnings or instability during task exit and execution transitions. No known exploits in the wild have been reported. The impact is limited to kernel-level perf event handling and may affect system stability or debugging accuracy.

A fix has been implemented to address this race condition by adding explicit checks for TASK_TOMBSTONE in the perf subsystem code. Since the vulnerability has been resolved, users should apply the official Linux kernel updates that include this fix. Patch status is not explicitly confirmed in the input data; therefore, verify with the vendor or Linux kernel advisory for the current remediation guidance.