tools/testing/selftests/bpf/prog_tests/probe_user.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/prog_tests/probe_user.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/prog_tests/probe_user.c
Extension
.c
Size
3134 bytes
Lines
111
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct test_pro_bss {
		struct sockaddr_in old;
		__u32 test_pid;
	};
	struct test_pro_bss results = {};
	size_t i;

	obj = bpf_object__open_file(obj_file, &opts);
	if (!ASSERT_OK_PTR(obj, "obj_open_file"))
		return;

	for (i = 0; i < prog_count; i++) {
		kprobe_progs[i] =
			bpf_object__find_program_by_name(obj, prog_names[i]);
		if (CHECK(!kprobe_progs[i], "find_probe",
			  "prog '%s' not found\n", prog_names[i]))
			goto cleanup;
	}

	{
		struct bpf_map *bss_map;
		struct test_pro_bss bss_init = {};

		bss_init.test_pid = getpid();
		bss_map = bpf_object__find_map_by_name(obj, "test_pro.bss");
		if (!ASSERT_OK_PTR(bss_map, "find_bss_map"))
			goto cleanup;
		if (!ASSERT_EQ(bpf_map__value_size(bss_map), sizeof(bss_init),
			       "bss_size"))
			goto cleanup;
		err = bpf_map__set_initial_value(bss_map, &bss_init,
						 sizeof(bss_init));
		if (!ASSERT_OK(err, "set_bss_init"))
			goto cleanup;
	}

	err = bpf_object__load(obj);
	if (CHECK(err, "obj_load", "err %d\n", err))
		goto cleanup;

	results_map_fd = bpf_find_map(__func__, obj, "test_pro.bss");
	if (CHECK(results_map_fd < 0, "find_bss_map",
		  "err %d\n", results_map_fd))
		goto cleanup;

	for (i = 0; i < prog_count; i++) {
		kprobe_links[i] = bpf_program__attach(kprobe_progs[i]);
		if (!ASSERT_OK_PTR(kprobe_links[i], "attach_kprobe"))
			goto cleanup;
	}

	memset(&curr, 0, sizeof(curr));
	in->sin_family = AF_INET;
	in->sin_port = htons(5555);
	in->sin_addr.s_addr = inet_addr("255.255.255.255");
	memcpy(&orig, &curr, sizeof(curr));

	sock_fd = socket(AF_INET, SOCK_STREAM, 0);
	if (CHECK(sock_fd < 0, "create_sock_fd", "err %d\n", sock_fd))
		goto cleanup;

	connect(sock_fd, &curr, sizeof(curr));
	close(sock_fd);

	err = bpf_map_lookup_elem(results_map_fd, &zero, &results);
	if (CHECK(err, "get_kprobe_res",
		  "failed to get kprobe res: %d\n", err))
		goto cleanup;

	memcpy(&tmp, &results.old, sizeof(tmp));

	in = (struct sockaddr_in *)&tmp;
	if (CHECK(memcmp(&tmp, &orig, sizeof(orig)), "check_kprobe_res",
		  "wrong kprobe res from probe read: %s:%u\n",
		  inet_ntoa(in->sin_addr), ntohs(in->sin_port)))
		goto cleanup;

	memset(&tmp, 0xab, sizeof(tmp));

	in = (struct sockaddr_in *)&curr;
	if (CHECK(memcmp(&curr, &tmp, sizeof(tmp)), "check_kprobe_res",
		  "wrong kprobe res from probe write: %s:%u\n",
		  inet_ntoa(in->sin_addr), ntohs(in->sin_port)))
		goto cleanup;
cleanup:
	for (i = 0; i < prog_count; i++)
		bpf_link__destroy(kprobe_links[i]);
	bpf_object__close(obj);
}

Annotation

Implementation Notes