selftests/bpf: Add an iterator selftest for bpf_sk_storage_delete

The eBPF program iterates over all entries (well, only one) of a socket
local storage map and deletes them all. The test makes sure that the
entry is indeed deleted.

Signed-off-by: Florent Revest <revest@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201204113609.1850150-4-revest@google.com
This commit is contained in:
Florent Revest 2020-12-04 12:36:07 +01:00 committed by Daniel Borkmann
parent a50a85e40c
commit 593f6d41ab
2 changed files with 87 additions and 0 deletions

View file

@ -20,6 +20,7 @@
#include "bpf_iter_bpf_percpu_hash_map.skel.h"
#include "bpf_iter_bpf_array_map.skel.h"
#include "bpf_iter_bpf_percpu_array_map.skel.h"
#include "bpf_iter_bpf_sk_storage_helpers.skel.h"
#include "bpf_iter_bpf_sk_storage_map.skel.h"
#include "bpf_iter_test_kern5.skel.h"
#include "bpf_iter_test_kern6.skel.h"
@ -913,6 +914,67 @@ static void test_bpf_percpu_array_map(void)
bpf_iter_bpf_percpu_array_map__destroy(skel);
}
/* An iterator program deletes all local storage in a map. */
static void test_bpf_sk_storage_delete(void)
{
DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
struct bpf_iter_bpf_sk_storage_helpers *skel;
union bpf_iter_link_info linfo;
int err, len, map_fd, iter_fd;
struct bpf_link *link;
int sock_fd = -1;
__u32 val = 42;
char buf[64];
skel = bpf_iter_bpf_sk_storage_helpers__open_and_load();
if (CHECK(!skel, "bpf_iter_bpf_sk_storage_helpers__open_and_load",
"skeleton open_and_load failed\n"))
return;
map_fd = bpf_map__fd(skel->maps.sk_stg_map);
sock_fd = socket(AF_INET6, SOCK_STREAM, 0);
if (CHECK(sock_fd < 0, "socket", "errno: %d\n", errno))
goto out;
err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST);
if (CHECK(err, "map_update", "map_update failed\n"))
goto out;
memset(&linfo, 0, sizeof(linfo));
linfo.map.map_fd = map_fd;
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
link = bpf_program__attach_iter(skel->progs.delete_bpf_sk_storage_map,
&opts);
if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n"))
goto out;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n"))
goto free_link;
/* do some tests */
while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
;
if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno)))
goto close_iter;
/* test results */
err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
if (CHECK(!err || errno != ENOENT, "bpf_map_lookup_elem",
"map value wasn't deleted (err=%d, errno=%d)\n", err, errno))
goto close_iter;
close_iter:
close(iter_fd);
free_link:
bpf_link__destroy(link);
out:
if (sock_fd >= 0)
close(sock_fd);
bpf_iter_bpf_sk_storage_helpers__destroy(skel);
}
static void test_bpf_sk_storage_map(void)
{
DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
@ -1067,6 +1129,8 @@ void test_bpf_iter(void)
test_bpf_percpu_array_map();
if (test__start_subtest("bpf_sk_storage_map"))
test_bpf_sk_storage_map();
if (test__start_subtest("bpf_sk_storage_delete"))
test_bpf_sk_storage_delete();
if (test__start_subtest("rdonly-buf-out-of-bound"))
test_rdonly_buf_out_of_bound();
if (test__start_subtest("buf-neg-offset"))

View file

@ -0,0 +1,23 @@
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Google LLC. */
#include "bpf_iter.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
char _license[] SEC("license") = "GPL";
struct {
__uint(type, BPF_MAP_TYPE_SK_STORAGE);
__uint(map_flags, BPF_F_NO_PREALLOC);
__type(key, int);
__type(value, int);
} sk_stg_map SEC(".maps");
SEC("iter/bpf_sk_storage_map")
int delete_bpf_sk_storage_map(struct bpf_iter__bpf_sk_storage_map *ctx)
{
if (ctx->sk)
bpf_sk_storage_delete(&sk_stg_map, ctx->sk);
return 0;
}