kernel: bpf: Check rcu_read_lock_trace_held() in bpf_map_lookup_percpu_elem()

In the Linux kernel, the following vulnerability has been resolved: bpf: Check rcureadlocktraceheld in bpfmaplookuppercpuelem bpfmaplookuppercpuelem helper is also available for sleepable bpf program. When BPF JIT is disabled or under 32-bit host, bpfmaplookuppercpuelem will not be inlined. Using...