// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */ #include "vmlinux.h" #include <bpf/bpf_helpers.h> #include "bpf_misc.h" char _license[] SEC("license") = "GPL"; struct inner_array_type { __uint(type, BPF_MAP_TYPE_ARRAY); __uint(map_flags, BPF_F_MMAPABLE); __type(key, __u32); __type(value, __u64); __uint(max_entries, 1); } inner_array SEC(".maps"); struct { __uint(type, BPF_MAP_TYPE_HASH_OF_MAPS); __uint(key_size, 4); __uint(value_size, 4); __uint(max_entries, 1); __array(values, struct inner_array_type); } outer_map SEC(".maps"); int pid = 0; __u64 match_value = 0x13572468; bool done = false; bool pid_match = false; bool outer_map_match = false; SEC("fentry/" SYS_PREFIX "sys_nanosleep") int add_to_list_in_inner_array(void *ctx) { __u32 curr_pid, zero = 0; struct bpf_map *map; __u64 *value; curr_pid = (u32)bpf_get_current_pid_tgid(); if (done || curr_pid != pid) return 0; pid_match = true; map = bpf_map_lookup_elem(&outer_map, &curr_pid); if (!map) return 0; outer_map_match = true; value = bpf_map_lookup_elem(map, &zero); if (!value) return 0; *value = match_value; done = true; return 0; }