// SPDX-License-Identifier: GPL-2.0 #include ssize_t get_base_addr() { size_t start; char buf[256]; FILE *f; f = fopen("/proc/self/maps", "r"); if (!f) return -errno; while (fscanf(f, "%zx-%*x %s %*s\n", &start, buf) == 2) { if (strcmp(buf, "r-xp") == 0) { fclose(f); return start; } } fclose(f); return -EINVAL; } void test_attach_probe(void) { const char *kprobe_name = "kprobe/sys_nanosleep"; const char *kretprobe_name = "kretprobe/sys_nanosleep"; const char *uprobe_name = "uprobe/trigger_func"; const char *uretprobe_name = "uretprobe/trigger_func"; const int kprobe_idx = 0, kretprobe_idx = 1; const int uprobe_idx = 2, uretprobe_idx = 3; const char *file = "./test_attach_probe.o"; struct bpf_program *kprobe_prog, *kretprobe_prog; struct bpf_program *uprobe_prog, *uretprobe_prog; struct bpf_object *obj; int err, prog_fd, duration = 0, res; struct bpf_link *kprobe_link = NULL; struct bpf_link *kretprobe_link = NULL; struct bpf_link *uprobe_link = NULL; struct bpf_link *uretprobe_link = NULL; int results_map_fd; size_t uprobe_offset; ssize_t base_addr; base_addr = get_base_addr(); if (CHECK(base_addr < 0, "get_base_addr", "failed to find base addr: %zd", base_addr)) return; uprobe_offset = (size_t)&get_base_addr - base_addr; /* load programs */ err = bpf_prog_load(file, BPF_PROG_TYPE_KPROBE, &obj, &prog_fd); if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno)) return; kprobe_prog = bpf_object__find_program_by_title(obj, kprobe_name); if (CHECK(!kprobe_prog, "find_probe", "prog '%s' not found\n", kprobe_name)) goto cleanup; kretprobe_prog = bpf_object__find_program_by_title(obj, kretprobe_name); if (CHECK(!kretprobe_prog, "find_probe", "prog '%s' not found\n", kretprobe_name)) goto cleanup; uprobe_prog = bpf_object__find_program_by_title(obj, uprobe_name); if (CHECK(!uprobe_prog, "find_probe", "prog '%s' not found\n", uprobe_name)) goto cleanup; uretprobe_prog = bpf_object__find_program_by_title(obj, uretprobe_name); if (CHECK(!uretprobe_prog, "find_probe", "prog '%s' not found\n", uretprobe_name)) goto cleanup; /* load maps */ results_map_fd = bpf_find_map(__func__, obj, "results_map"); if (CHECK(results_map_fd < 0, "find_results_map", "err %d\n", results_map_fd)) goto cleanup; kprobe_link = bpf_program__attach_kprobe(kprobe_prog, false /* retprobe */, SYS_NANOSLEEP_KPROBE_NAME); if (CHECK(IS_ERR(kprobe_link), "attach_kprobe", "err %ld\n", PTR_ERR(kprobe_link))) { kprobe_link = NULL; goto cleanup; } kretprobe_link = bpf_program__attach_kprobe(kretprobe_prog, true /* retprobe */, SYS_NANOSLEEP_KPROBE_NAME); if (CHECK(IS_ERR(kretprobe_link), "attach_kretprobe", "err %ld\n", PTR_ERR(kretprobe_link))) { kretprobe_link = NULL; goto cleanup; } uprobe_link = bpf_program__attach_uprobe(uprobe_prog, false /* retprobe */, 0 /* self pid */, "/proc/self/exe", uprobe_offset); if (CHECK(IS_ERR(uprobe_link), "attach_uprobe", "err %ld\n", PTR_ERR(uprobe_link))) { uprobe_link = NULL; goto cleanup; } uretprobe_link = bpf_program__attach_uprobe(uretprobe_prog, true /* retprobe */, -1 /* any pid */, "/proc/self/exe", uprobe_offset); if (CHECK(IS_ERR(uretprobe_link), "attach_uretprobe", "err %ld\n", PTR_ERR(uretprobe_link))) { uretprobe_link = NULL; goto cleanup; } /* trigger & validate kprobe && kretprobe */ usleep(1); err = bpf_map_lookup_elem(results_map_fd, &kprobe_idx, &res); if (CHECK(err, "get_kprobe_res", "failed to get kprobe res: %d\n", err)) goto cleanup; if (CHECK(res != kprobe_idx + 1, "check_kprobe_res", "wrong kprobe res: %d\n", res)) goto cleanup; err = bpf_map_lookup_elem(results_map_fd, &kretprobe_idx, &res); if (CHECK(err, "get_kretprobe_res", "failed to get kretprobe res: %d\n", err)) goto cleanup; if (CHECK(res != kretprobe_idx + 1, "check_kretprobe_res", "wrong kretprobe res: %d\n", res)) goto cleanup; /* trigger & validate uprobe & uretprobe */ get_base_addr(); err = bpf_map_lookup_elem(results_map_fd, &uprobe_idx, &res); if (CHECK(err, "get_uprobe_res", "failed to get uprobe res: %d\n", err)) goto cleanup; if (CHECK(res != uprobe_idx + 1, "check_uprobe_res", "wrong uprobe res: %d\n", res)) goto cleanup; err = bpf_map_lookup_elem(results_map_fd, &uretprobe_idx, &res); if (CHECK(err, "get_uretprobe_res", "failed to get uretprobe res: %d\n", err)) goto cleanup; if (CHECK(res != uretprobe_idx + 1, "check_uretprobe_res", "wrong uretprobe res: %d\n", res)) goto cleanup; cleanup: bpf_link__destroy(kprobe_link); bpf_link__destroy(kretprobe_link); bpf_link__destroy(uprobe_link); bpf_link__destroy(uretprobe_link); bpf_object__close(obj); }