Commit d1a783da authored by Daniel Borkmann's avatar Daniel Borkmann Committed by Andrii Nakryiko
Browse files

selftest/bpf: Add various selftests for program limits 



Add various tests to check maximum number of supported programs
being attached:

  # ./vmtest.sh -- ./test_progs -t tc_opts
  [...]
  ./test_progs -t tc_opts
  [    1.185325] bpf_testmod: loading out-of-tree module taints kernel.
  [    1.186826] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  [    1.270123] tsc: Refined TSC clocksource calibration: 3407.988 MHz
  [    1.272428] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x311fc932722, max_idle_ns: 440795381586 ns
  [    1.276408] clocksource: Switched to clocksource tsc
  #252     tc_opts_after:OK
  #253     tc_opts_append:OK
  #254     tc_opts_basic:OK
  #255     tc_opts_before:OK
  #256     tc_opts_chain_classic:OK
  #257     tc_opts_chain_mixed:OK
  #258     tc_opts_delete_empty:OK
  #259     tc_opts_demixed:OK
  #260     tc_opts_detach:OK
  #261     tc_opts_detach_after:OK
  #262     tc_opts_detach_before:OK
  #263     tc_opts_dev_cleanup:OK
  #264     tc_opts_invalid:OK
  #265     tc_opts_max:OK              <--- (new test)
  #266     tc_opts_mixed:OK
  #267     tc_opts_prepend:OK
  #268     tc_opts_replace:OK
  #269     tc_opts_revision:OK
  Summary: 18/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230929204121.20305-2-daniel@iogearbox.net
parent f9b0e108

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

+84 −0
Original line number Diff line number Diff line
@@ -2378,3 +2378,87 @@ void serial_test_tc_opts_chain_mixed(void) 
	test_tc_chain_mixed(BPF_TCX_INGRESS);

	test_tc_chain_mixed(BPF_TCX_EGRESS);

}



static int generate_dummy_prog(void)

{

	const struct bpf_insn prog_insns[] = {

		BPF_MOV64_IMM(BPF_REG_0, 0),

		BPF_EXIT_INSN(),

	};

	const size_t prog_insn_cnt = sizeof(prog_insns) / sizeof(struct bpf_insn);

	LIBBPF_OPTS(bpf_prog_load_opts, opts);

	const size_t log_buf_sz = 256;

	char *log_buf;

	int fd = -1;



	log_buf = malloc(log_buf_sz);

	if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc"))

		return fd;

	opts.log_buf = log_buf;

	opts.log_size = log_buf_sz;



	log_buf[0] = '\0';

	opts.log_level = 0;

	fd = bpf_prog_load(BPF_PROG_TYPE_SCHED_CLS, "tcx_prog", "GPL",

			   prog_insns, prog_insn_cnt, &opts);

	ASSERT_STREQ(log_buf, "", "log_0");

	ASSERT_GE(fd, 0, "prog_fd");

	free(log_buf);

	return fd;

}



static void test_tc_opts_max_target(int target, int flags, bool relative)

{

	int err, ifindex, i, prog_fd, last_fd = -1;

	LIBBPF_OPTS(bpf_prog_attach_opts, opta);

	const int max_progs = 63;



	ASSERT_OK(system("ip link add dev tcx_opts1 type veth peer name tcx_opts2"), "add veth");

	ifindex = if_nametoindex("tcx_opts1");

	ASSERT_NEQ(ifindex, 0, "non_zero_ifindex");



	assert_mprog_count_ifindex(ifindex, target, 0);



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

		prog_fd = generate_dummy_prog();

		if (!ASSERT_GE(prog_fd, 0, "dummy_prog"))

			goto cleanup;

		err = bpf_prog_attach_opts(prog_fd, ifindex, target, &opta);

		if (!ASSERT_EQ(err, 0, "prog_attach"))

			goto cleanup;

		assert_mprog_count_ifindex(ifindex, target, i + 1);

		if (i == max_progs - 1 && relative)

			last_fd = prog_fd;

		else

			close(prog_fd);

	}



	prog_fd = generate_dummy_prog();

	if (!ASSERT_GE(prog_fd, 0, "dummy_prog"))

		goto cleanup;

	opta.flags = flags;

	if (last_fd > 0)

		opta.relative_fd = last_fd;

	err = bpf_prog_attach_opts(prog_fd, ifindex, target, &opta);

	ASSERT_EQ(err, -ERANGE, "prog_64_attach");

	assert_mprog_count_ifindex(ifindex, target, max_progs);

	close(prog_fd);

cleanup:

	if (last_fd > 0)

		close(last_fd);

	ASSERT_OK(system("ip link del dev tcx_opts1"), "del veth");

	ASSERT_EQ(if_nametoindex("tcx_opts1"), 0, "dev1_removed");

	ASSERT_EQ(if_nametoindex("tcx_opts2"), 0, "dev2_removed");

}



void serial_test_tc_opts_max(void)

{

	test_tc_opts_max_target(BPF_TCX_INGRESS, 0, false);

	test_tc_opts_max_target(BPF_TCX_EGRESS, 0, false);



	test_tc_opts_max_target(BPF_TCX_INGRESS, BPF_F_BEFORE, false);

	test_tc_opts_max_target(BPF_TCX_EGRESS, BPF_F_BEFORE, true);



	test_tc_opts_max_target(BPF_TCX_INGRESS, BPF_F_AFTER, true);

	test_tc_opts_max_target(BPF_TCX_EGRESS, BPF_F_AFTER, false);

}