Commit e7215f57 authored by Stanislav Fomichev's avatar Stanislav Fomichev Committed by Alexei Starovoitov
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selftests/bpf: Make sure bpf_{g,s}et_retval is exposed everywhere 



For each hook, have a simple bpf_set_retval(bpf_get_retval) program
and make sure it loads for the hooks we want. The exceptions are
the hooks which don't propagate the error to the callers:

- sockops
- recvmsg
- getpeername
- getsockname
- cg_skb ingress and egress

Acked-by: default avatarMartin KaFai Lau <kafai@fb.com>
Signed-off-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220823222555.523590-6-sdf@google.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 2172fb80

tools/testing/selftests/bpf/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -323,6 +323,7 @@ $(OUTPUT)/test_l4lb_noinline.o: BPF_CFLAGS += -fno-inline 
$(OUTPUT)/test_xdp_noinline.o: BPF_CFLAGS += -fno-inline



$(OUTPUT)/flow_dissector_load.o: flow_dissector_load.h

$(OUTPUT)/cgroup_getset_retval_hooks.o: cgroup_getset_retval_hooks.h



# Build BPF object using Clang

# $1 - input .c file

tools/testing/selftests/bpf/cgroup_getset_retval_hooks.h

0 → 100644
+25 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */



BPF_RETVAL_HOOK(ingress, "cgroup_skb/ingress", __sk_buff, -EINVAL)

BPF_RETVAL_HOOK(egress, "cgroup_skb/egress", __sk_buff, -EINVAL)

BPF_RETVAL_HOOK(sock_create, "cgroup/sock_create", bpf_sock, 0)

BPF_RETVAL_HOOK(sock_ops, "sockops", bpf_sock_ops, -EINVAL)

BPF_RETVAL_HOOK(dev, "cgroup/dev", bpf_cgroup_dev_ctx, 0)

BPF_RETVAL_HOOK(bind4, "cgroup/bind4", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(bind6, "cgroup/bind6", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(connect4, "cgroup/connect4", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(connect6, "cgroup/connect6", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(post_bind4, "cgroup/post_bind4", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(post_bind6, "cgroup/post_bind6", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(sendmsg4, "cgroup/sendmsg4", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(sendmsg6, "cgroup/sendmsg6", bpf_sock_addr, 0)

BPF_RETVAL_HOOK(sysctl, "cgroup/sysctl", bpf_sysctl, 0)

BPF_RETVAL_HOOK(recvmsg4, "cgroup/recvmsg4", bpf_sock_addr, -EINVAL)

BPF_RETVAL_HOOK(recvmsg6, "cgroup/recvmsg6", bpf_sock_addr, -EINVAL)

BPF_RETVAL_HOOK(getsockopt, "cgroup/getsockopt", bpf_sockopt, 0)

BPF_RETVAL_HOOK(setsockopt, "cgroup/setsockopt", bpf_sockopt, 0)

BPF_RETVAL_HOOK(getpeername4, "cgroup/getpeername4", bpf_sock_addr, -EINVAL)

BPF_RETVAL_HOOK(getpeername6, "cgroup/getpeername6", bpf_sock_addr, -EINVAL)

BPF_RETVAL_HOOK(getsockname4, "cgroup/getsockname4", bpf_sock_addr, -EINVAL)

BPF_RETVAL_HOOK(getsockname6, "cgroup/getsockname6", bpf_sock_addr, -EINVAL)

BPF_RETVAL_HOOK(sock_release, "cgroup/sock_release", bpf_sock, 0)

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

+48 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 


#include "cgroup_getset_retval_setsockopt.skel.h"

#include "cgroup_getset_retval_getsockopt.skel.h"

#include "cgroup_getset_retval_hooks.skel.h"



#define SOL_CUSTOM	0xdeadbeef
@@ -433,6 +434,50 @@ static void test_getsockopt_retval_sync(int cgroup_fd, int sock_fd) 
	cgroup_getset_retval_getsockopt__destroy(obj);

}



struct exposed_hook {

	const char *name;

	int expected_err;

} exposed_hooks[] = {



#define BPF_RETVAL_HOOK(NAME, SECTION, CTX, EXPECTED_ERR) \

	{ \

		.name = #NAME, \

		.expected_err = EXPECTED_ERR, \

	},



#include "cgroup_getset_retval_hooks.h"



#undef BPF_RETVAL_HOOK

};



static void test_exposed_hooks(int cgroup_fd, int sock_fd)

{

	struct cgroup_getset_retval_hooks *skel;

	struct bpf_program *prog;

	int err;

	int i;



	for (i = 0; i < ARRAY_SIZE(exposed_hooks); i++) {

		skel = cgroup_getset_retval_hooks__open();

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

			continue;



		prog = bpf_object__find_program_by_name(skel->obj, exposed_hooks[i].name);

		if (!ASSERT_NEQ(prog, NULL, "bpf_object__find_program_by_name"))

			goto close_skel;



		err = bpf_program__set_autoload(prog, true);

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

			goto close_skel;



		err = cgroup_getset_retval_hooks__load(skel);

		ASSERT_EQ(err, exposed_hooks[i].expected_err, "expected_err");



close_skel:

		cgroup_getset_retval_hooks__destroy(skel);

	}

}



void test_cgroup_getset_retval(void)

{

	int cgroup_fd = -1;
@@ -476,6 +521,9 @@ void test_cgroup_getset_retval(void) 
	if (test__start_subtest("getsockopt-retval_sync"))

		test_getsockopt_retval_sync(cgroup_fd, sock_fd);



	if (test__start_subtest("exposed_hooks"))

		test_exposed_hooks(cgroup_fd, sock_fd);



close_fd:

	close(cgroup_fd);

}

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

0 → 100644
+16 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only



#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>



#define BPF_RETVAL_HOOK(name, section, ctx, expected_err) \

	__attribute__((__section__("?" section))) \

	int name(struct ctx *_ctx) \

	{ \

		bpf_set_retval(bpf_get_retval()); \

		return 1; \

	}



#include "cgroup_getset_retval_hooks.h"



#undef BPF_RETVAL_HOOK