CVE-2025-21825 bpf: Cancel the running bpf_timer through kworker for PREEMPT_RT

In the Linux kernel, the following vulnerability has been resolved: bpf: Cancel the running bpftimer through kworker for PREEMPTRT During the update procedure, when overwrite element in a pre-allocated htab, the freeing of oldelement is protected by the bucket lock. The reason why the bucket lock...