Commit c6f420ac authored by Kumar Kartikeya Dwivedi's avatar Kumar Kartikeya Dwivedi Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add negative tests for new nf_conntrack kfuncs 



Test cases we care about and ensure improper usage is caught and
rejected by the verifier.

Signed-off-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220721134245.2450-13-memxor@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 6eb7fba0

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

+55 −1
Original line number Diff line number Diff line
@@ -2,13 +2,29 @@ 
#include <test_progs.h>

#include <network_helpers.h>

#include "test_bpf_nf.skel.h"

#include "test_bpf_nf_fail.skel.h"



static char log_buf[1024 * 1024];



struct {

	const char *prog_name;

	const char *err_msg;

} test_bpf_nf_fail_tests[] = {

	{ "alloc_release", "kernel function bpf_ct_release args#0 expected pointer to STRUCT nf_conn but" },

	{ "insert_insert", "kernel function bpf_ct_insert_entry args#0 expected pointer to STRUCT nf_conn___init but" },

	{ "lookup_insert", "kernel function bpf_ct_insert_entry args#0 expected pointer to STRUCT nf_conn___init but" },

	{ "set_timeout_after_insert", "kernel function bpf_ct_set_timeout args#0 expected pointer to STRUCT nf_conn___init but" },

	{ "set_status_after_insert", "kernel function bpf_ct_set_status args#0 expected pointer to STRUCT nf_conn___init but" },

	{ "change_timeout_after_alloc", "kernel function bpf_ct_change_timeout args#0 expected pointer to STRUCT nf_conn but" },

	{ "change_status_after_alloc", "kernel function bpf_ct_change_status args#0 expected pointer to STRUCT nf_conn but" },

};



enum {

	TEST_XDP,

	TEST_TC_BPF,

};



void test_bpf_nf_ct(int mode)

static void test_bpf_nf_ct(int mode)

{

	struct test_bpf_nf *skel;

	int prog_fd, err;
@@ -51,10 +67,48 @@ void test_bpf_nf_ct(int mode) 
	test_bpf_nf__destroy(skel);

}



static void test_bpf_nf_ct_fail(const char *prog_name, const char *err_msg)

{

	LIBBPF_OPTS(bpf_object_open_opts, opts, .kernel_log_buf = log_buf,

						.kernel_log_size = sizeof(log_buf),

						.kernel_log_level = 1);

	struct test_bpf_nf_fail *skel;

	struct bpf_program *prog;

	int ret;



	skel = test_bpf_nf_fail__open_opts(&opts);

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

		return;



	prog = bpf_object__find_program_by_name(skel->obj, prog_name);

	if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))

		goto end;



	bpf_program__set_autoload(prog, true);



	ret = test_bpf_nf_fail__load(skel);

	if (!ASSERT_ERR(ret, "test_bpf_nf_fail__load must fail"))

		goto end;



	if (!ASSERT_OK_PTR(strstr(log_buf, err_msg), "expected error message")) {

		fprintf(stderr, "Expected: %s\n", err_msg);

		fprintf(stderr, "Verifier: %s\n", log_buf);

	}



end:

	test_bpf_nf_fail__destroy(skel);

}



void test_bpf_nf(void)

{

	int i;

	if (test__start_subtest("xdp-ct"))

		test_bpf_nf_ct(TEST_XDP);

	if (test__start_subtest("tc-bpf-ct"))

		test_bpf_nf_ct(TEST_TC_BPF);

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

		if (test__start_subtest(test_bpf_nf_fail_tests[i].prog_name))

			test_bpf_nf_ct_fail(test_bpf_nf_fail_tests[i].prog_name,

					    test_bpf_nf_fail_tests[i].err_msg);

	}

}

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

0 → 100644
+134 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#include <vmlinux.h>

#include <bpf/bpf_tracing.h>

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_core_read.h>



struct nf_conn;



struct bpf_ct_opts___local {

	s32 netns_id;

	s32 error;

	u8 l4proto;

	u8 reserved[3];

} __attribute__((preserve_access_index));



struct nf_conn *bpf_skb_ct_alloc(struct __sk_buff *, struct bpf_sock_tuple *, u32,

				 struct bpf_ct_opts___local *, u32) __ksym;

struct nf_conn *bpf_skb_ct_lookup(struct __sk_buff *, struct bpf_sock_tuple *, u32,

				  struct bpf_ct_opts___local *, u32) __ksym;

struct nf_conn *bpf_ct_insert_entry(struct nf_conn *) __ksym;

void bpf_ct_release(struct nf_conn *) __ksym;

void bpf_ct_set_timeout(struct nf_conn *, u32) __ksym;

int bpf_ct_change_timeout(struct nf_conn *, u32) __ksym;

int bpf_ct_set_status(struct nf_conn *, u32) __ksym;

int bpf_ct_change_status(struct nf_conn *, u32) __ksym;



SEC("?tc")

int alloc_release(struct __sk_buff *ctx)

{

	struct bpf_ct_opts___local opts = {};

	struct bpf_sock_tuple tup = {};

	struct nf_conn *ct;



	ct = bpf_skb_ct_alloc(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));

	if (!ct)

		return 0;

	bpf_ct_release(ct);

	return 0;

}



SEC("?tc")

int insert_insert(struct __sk_buff *ctx)

{

	struct bpf_ct_opts___local opts = {};

	struct bpf_sock_tuple tup = {};

	struct nf_conn *ct;



	ct = bpf_skb_ct_alloc(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));

	if (!ct)

		return 0;

	ct = bpf_ct_insert_entry(ct);

	if (!ct)

		return 0;

	ct = bpf_ct_insert_entry(ct);

	return 0;

}



SEC("?tc")

int lookup_insert(struct __sk_buff *ctx)

{

	struct bpf_ct_opts___local opts = {};

	struct bpf_sock_tuple tup = {};

	struct nf_conn *ct;



	ct = bpf_skb_ct_lookup(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));

	if (!ct)

		return 0;

	bpf_ct_insert_entry(ct);

	return 0;

}



SEC("?tc")

int set_timeout_after_insert(struct __sk_buff *ctx)

{

	struct bpf_ct_opts___local opts = {};

	struct bpf_sock_tuple tup = {};

	struct nf_conn *ct;



	ct = bpf_skb_ct_alloc(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));

	if (!ct)

		return 0;

	ct = bpf_ct_insert_entry(ct);

	if (!ct)

		return 0;

	bpf_ct_set_timeout(ct, 0);

	return 0;

}



SEC("?tc")

int set_status_after_insert(struct __sk_buff *ctx)

{

	struct bpf_ct_opts___local opts = {};

	struct bpf_sock_tuple tup = {};

	struct nf_conn *ct;



	ct = bpf_skb_ct_alloc(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));

	if (!ct)

		return 0;

	ct = bpf_ct_insert_entry(ct);

	if (!ct)

		return 0;

	bpf_ct_set_status(ct, 0);

	return 0;

}



SEC("?tc")

int change_timeout_after_alloc(struct __sk_buff *ctx)

{

	struct bpf_ct_opts___local opts = {};

	struct bpf_sock_tuple tup = {};

	struct nf_conn *ct;



	ct = bpf_skb_ct_alloc(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));

	if (!ct)

		return 0;

	bpf_ct_change_timeout(ct, 0);

	return 0;

}



SEC("?tc")

int change_status_after_alloc(struct __sk_buff *ctx)

{

	struct bpf_ct_opts___local opts = {};

	struct bpf_sock_tuple tup = {};

	struct nf_conn *ct;



	ct = bpf_skb_ct_alloc(ctx, &tup, sizeof(tup.ipv4), &opts, sizeof(opts));

	if (!ct)

		return 0;

	bpf_ct_change_status(ct, 0);

	return 0;

}



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