Sažetak |
In the Linux kernel, the following vulnerability has been resolved:
bpf: Check rcu_read_lock_trace_held() in bpf_map_lookup_percpu_elem()
bpf_map_lookup_percpu_elem() helper is also available for sleepable bpf
program. When BPF JIT is disabled or under 32-bit host,
bpf_map_lookup_percpu_elem() will not be inlined. Using it in a
sleepable bpf program will trigger the warning in
bpf_map_lookup_percpu_elem(), because the bpf program only holds
rcu_read_lock_trace lock. Therefore, add the missed check. |