CVE-2026-98861 fprobe: Use guard(rcu_sched_notrace) and check rcu_is_watching()

In the Linux kernel, the following vulnerability has been resolved: fprobe: Use guardrcuschednotrace and check rcuiswatching unregisterfprobe and unregisterfprobeasync used by BPF kprobe-multi rely on standard RCU grace periods synchronizercu and callrcu to wait until in-flight fprobe handlers...

CVE-2026-98861

The Linux kernel contains a vulnerability in the fprobe mechanism used by BPF kprobe-multi . The issue arises because unregister_fprobe() and unregister_fprobe_async() rely on standard RCU grace periods (synchronize_rcu() and call_rcu()) to wait for in-flight handlers. If a handler executes while...