Commit 939a1a94 authored by Hou Tao's avatar Hou Tao Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add write tests for sk local storage map iterator 



Add test to validate the overwrite of sock local storage map value in
map iterator and another one to ensure out-of-bound value writing is
rejected.

Signed-off-by: default avatarHou Tao <houtao1@huawei.com>
Acked-by: default avatarYonghong Song <yhs@fb.com>
Acked-by: default avatarMartin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220810080538.1845898-9-houtao@huaweicloud.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 5836d81e

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

+18 −2
Original line number Diff line number Diff line
@@ -1076,7 +1076,7 @@ static void test_bpf_sk_stoarge_map_iter_fd(void) 
	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_map__open_and_load"))

		return;



	do_read_map_iter_fd(&skel->skeleton, skel->progs.dump_bpf_sk_storage_map,

	do_read_map_iter_fd(&skel->skeleton, skel->progs.rw_bpf_sk_storage_map,

			    skel->maps.sk_stg_map);



	bpf_iter_bpf_sk_storage_map__destroy(skel);
@@ -1117,7 +1117,15 @@ static void test_bpf_sk_storage_map(void) 
	linfo.map.map_fd = map_fd;

	opts.link_info = &linfo;

	opts.link_info_len = sizeof(linfo);

	link = bpf_program__attach_iter(skel->progs.dump_bpf_sk_storage_map, &opts);

	link = bpf_program__attach_iter(skel->progs.oob_write_bpf_sk_storage_map, &opts);

	err = libbpf_get_error(link);

	if (!ASSERT_EQ(err, -EACCES, "attach_oob_write_iter")) {

		if (!err)

			bpf_link__destroy(link);

		goto out;

	}



	link = bpf_program__attach_iter(skel->progs.rw_bpf_sk_storage_map, &opts);

	if (!ASSERT_OK_PTR(link, "attach_iter"))

		goto out;
@@ -1125,6 +1133,7 @@ static void test_bpf_sk_storage_map(void) 
	if (!ASSERT_GE(iter_fd, 0, "create_iter"))

		goto free_link;



	skel->bss->to_add_val = time(NULL);

	/* do some tests */

	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)

		;
@@ -1138,6 +1147,13 @@ static void test_bpf_sk_storage_map(void) 
	if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))

		goto close_iter;



	for (i = 0; i < num_sockets; i++) {

		err = bpf_map_lookup_elem(map_fd, &sock_fd[i], &val);

		if (!ASSERT_OK(err, "map_lookup") ||

		    !ASSERT_EQ(val, i + 1 + skel->bss->to_add_val, "check_map_value"))

			break;

	}



close_iter:

	close(iter_fd);

free_link:

tools/testing/selftests/bpf/progs/bpf_iter_bpf_sk_storage_map.c

+20 −2
Original line number Diff line number Diff line
@@ -16,19 +16,37 @@ struct { 


__u32 val_sum = 0;

__u32 ipv6_sk_count = 0;

__u32 to_add_val = 0;



SEC("iter/bpf_sk_storage_map")

int dump_bpf_sk_storage_map(struct bpf_iter__bpf_sk_storage_map *ctx)

int rw_bpf_sk_storage_map(struct bpf_iter__bpf_sk_storage_map *ctx)

{

	struct sock *sk = ctx->sk;

	__u32 *val = ctx->value;



	if (sk == (void *)0 || val == (void *)0)

	if (sk == NULL || val == NULL)

		return 0;



	if (sk->sk_family == AF_INET6)

		ipv6_sk_count++;



	val_sum += *val;



	*val += to_add_val;



	return 0;

}



SEC("iter/bpf_sk_storage_map")

int oob_write_bpf_sk_storage_map(struct bpf_iter__bpf_sk_storage_map *ctx)

{

	struct sock *sk = ctx->sk;

	__u32 *val = ctx->value;



	if (sk == NULL || val == NULL)

		return 0;



	*(val + 1) = 0xdeadbeef;



	return 0;

}