// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2021 Facebook */ #include <linux/bpf.h> #include <bpf/bpf_helpers.h> #include "bpf_misc.h" char _license[] SEC("license") = "GPL"; struct bpf_map; struct { __uint(type, BPF_MAP_TYPE_ARRAY); __type(key, __u32); __type(value, __u32); __uint(max_entries, 1000); } map_random_data SEC(".maps"); struct map_bloom_type { __uint(type, BPF_MAP_TYPE_BLOOM_FILTER); __type(value, __u32); __uint(max_entries, 10000); __uint(map_extra, 5); } map_bloom SEC(".maps"); struct { __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); __type(key, int); __type(value, int); __uint(max_entries, 1); __array(values, struct map_bloom_type); } outer_map SEC(".maps"); struct callback_ctx { struct bpf_map *map; }; int error = 0; static __u64 check_elem(struct bpf_map *map, __u32 *key, __u32 *val, struct callback_ctx *data) { int err; err = bpf_map_peek_elem(data->map, val); if (err) { error |= 1; return 1; /* stop the iteration */ } return 0; } SEC("fentry/" SYS_PREFIX "sys_getpgid") int inner_map(void *ctx) { struct bpf_map *inner_map; struct callback_ctx data; int key = 0; inner_map = bpf_map_lookup_elem(&outer_map, &key); if (!inner_map) { error |= 2; return 0; } data.map = inner_map; bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0); return 0; } SEC("fentry/" SYS_PREFIX "sys_getpgid") int check_bloom(void *ctx) { struct callback_ctx data; data.map = (struct bpf_map *)&map_bloom; bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0); return 0; }