1 // SPDX-License-Identifier: GPL-2.0
4 #include <bpf/bpf_tracing.h>
5 #include <bpf/bpf_helpers.h>
8 struct bpf_timer timer;
9 struct bpf_spin_lock lock;
13 __uint(type, BPF_MAP_TYPE_ARRAY);
14 __uint(max_entries, 1);
16 __type(value, struct map_elem);
20 __uint(type, BPF_MAP_TYPE_HASH);
21 __uint(max_entries, 1);
23 __type(value, struct map_elem);
27 int crash_map = 0; /* 0 for amap, 1 for hmap */
29 SEC("fentry/do_nanosleep")
30 int sys_enter(void *ctx)
32 struct map_elem *e, value = {};
33 void *map = crash_map ? (void *)&hmap : (void *)&amap;
35 if (bpf_get_current_task_btf()->tgid != pid)
38 *(void **)&value = (void *)0xdeadcaf3;
40 bpf_map_update_elem(map, &(int){0}, &value, 0);
41 /* For array map, doing bpf_map_update_elem will do a
42 * check_and_free_timer_in_array, which will trigger the crash if timer
43 * pointer was overwritten, for hmap we need to use bpf_timer_cancel.
46 e = bpf_map_lookup_elem(map, &(int){0});
49 bpf_timer_cancel(&e->timer);
54 char _license[] SEC("license") = "GPL";