Commit 651d49f1 authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Andrii Nakryiko
Browse files

selftests/bpf: Verify struct_ops autoload/autocreate sync 



Check that autocreate flags of struct_ops map cause autoload of
struct_ops corresponding programs:
- when struct_ops program is referenced only from a map for which
  autocreate is set to false, that program should not be loaded;
- when struct_ops program with autoload == false is set to be used
  from a map with autocreate == true using shadow var,
  that program should be loaded;
- when struct_ops program is not referenced from any map object load
  should fail.

Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-10-eddyz87@gmail.com
parent fe9d049c

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

+32 −0
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 


#include <test_progs.h>

#include "bad_struct_ops.skel.h"

#include "bad_struct_ops2.skel.h"



static void invalid_prog_reuse(void)

{
@@ -28,8 +29,39 @@ static void invalid_prog_reuse(void) 
	bad_struct_ops__destroy(skel);

}



static void unused_program(void)

{

	struct bad_struct_ops2 *skel;

	char *log = NULL;

	int err;



	skel = bad_struct_ops2__open();

	if (!ASSERT_OK_PTR(skel, "bad_struct_ops2__open"))

		return;



	/* struct_ops programs not referenced from any maps are open

	 * with autoload set to true.

	 */

	ASSERT_TRUE(bpf_program__autoload(skel->progs.foo), "foo autoload == true");



	if (start_libbpf_log_capture())

		goto cleanup;



	err = bad_struct_ops2__load(skel);

	ASSERT_ERR(err, "bad_struct_ops2__load should fail");

	log = stop_libbpf_log_capture();

	ASSERT_HAS_SUBSTR(log, "prog 'foo': failed to load",

			  "message about 'foo' failing to load");



cleanup:

	free(log);

	bad_struct_ops2__destroy(skel);

}



void test_bad_struct_ops(void)

{

	if (test__start_subtest("invalid_prog_reuse"))

		invalid_prog_reuse();

	if (test__start_subtest("unused_program"))

		unused_program();

}

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

+47 −4
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 


#include <test_progs.h>

#include "struct_ops_autocreate.skel.h"

#include "struct_ops_autocreate2.skel.h"



static void cant_load_full_object(void)

{
@@ -43,18 +44,20 @@ static void can_load_partial_object(void) 
	if (!ASSERT_OK_PTR(skel, "struct_ops_autocreate__open_opts"))

		return;



	err = bpf_program__set_autoload(skel->progs.test_2, false);

	if (!ASSERT_OK(err, "bpf_program__set_autoload"))

		goto cleanup;



	err = bpf_map__set_autocreate(skel->maps.testmod_2, false);

	if (!ASSERT_OK(err, "bpf_map__set_autocreate"))

		goto cleanup;



	ASSERT_TRUE(bpf_program__autoload(skel->progs.test_1), "test_1 default autoload");

	ASSERT_TRUE(bpf_program__autoload(skel->progs.test_2), "test_2 default autoload");



	err = struct_ops_autocreate__load(skel);

	if (ASSERT_OK(err, "struct_ops_autocreate__load"))

		goto cleanup;



	ASSERT_TRUE(bpf_program__autoload(skel->progs.test_1), "test_1 actual autoload");

	ASSERT_FALSE(bpf_program__autoload(skel->progs.test_2), "test_2 actual autoload");



	link = bpf_map__attach_struct_ops(skel->maps.testmod_1);

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

		goto cleanup;
@@ -67,10 +70,50 @@ static void can_load_partial_object(void) 
	struct_ops_autocreate__destroy(skel);

}



/* Swap test_mod1->test_1 program from 'bar' to 'foo' using shadow vars.

 * test_mod1 load should enable autoload for 'foo'.

 */

static void autoload_and_shadow_vars(void)

{

	struct struct_ops_autocreate2 *skel = NULL;

	struct bpf_link *link = NULL;

	int err;



	skel = struct_ops_autocreate2__open();

	if (!ASSERT_OK_PTR(skel, "struct_ops_autocreate__open_opts"))

		return;



	ASSERT_FALSE(bpf_program__autoload(skel->progs.foo), "foo default autoload");

	ASSERT_FALSE(bpf_program__autoload(skel->progs.bar), "bar default autoload");



	/* loading map testmod_1 would switch foo's autoload to true */

	skel->struct_ops.testmod_1->test_1 = skel->progs.foo;



	err = struct_ops_autocreate2__load(skel);

	if (ASSERT_OK(err, "struct_ops_autocreate__load"))

		goto cleanup;



	ASSERT_TRUE(bpf_program__autoload(skel->progs.foo), "foo actual autoload");

	ASSERT_FALSE(bpf_program__autoload(skel->progs.bar), "bar actual autoload");



	link = bpf_map__attach_struct_ops(skel->maps.testmod_1);

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

		goto cleanup;



	/* test_1() would be called from bpf_dummy_reg2() in bpf_testmod.c */

	err = ASSERT_EQ(skel->bss->test_1_result, 42, "test_1_result");



cleanup:

	bpf_link__destroy(link);

	struct_ops_autocreate2__destroy(skel);

}



void test_struct_ops_autocreate(void)

{

	if (test__start_subtest("cant_load_full_object"))

		cant_load_full_object();

	if (test__start_subtest("can_load_partial_object"))

		can_load_partial_object();

	if (test__start_subtest("autoload_and_shadow_vars"))

		autoload_and_shadow_vars();

}

tools/testing/selftests/bpf/progs/bad_struct_ops2.c

0 → 100644
+14 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>



char _license[] SEC("license") = "GPL";



/* This is an unused struct_ops program, it lacks corresponding

 * struct_ops map, which provides attachment information.

 * W/o additional configuration attempt to load such

 * BPF object file would fail.

 */

SEC("struct_ops/foo")

void foo(void) {}

tools/testing/selftests/bpf/progs/struct_ops_autocreate2.c

0 → 100644
+32 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>



char _license[] SEC("license") = "GPL";



int test_1_result = 0;



SEC("?struct_ops/test_1")

int BPF_PROG(foo)

{

	test_1_result = 42;

	return 0;

}



SEC("?struct_ops/test_1")

int BPF_PROG(bar)

{

	test_1_result = 24;

	return 0;

}



struct bpf_testmod_ops {

	int (*test_1)(void);

};



SEC(".struct_ops.link")

struct bpf_testmod_ops testmod_1 = {

	.test_1 = (void *)bar

};