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bpf_iter.c
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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#include <test_progs.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <task_local_storage_helpers.h>
#include "bpf_iter_ipv6_route.skel.h"
#include "bpf_iter_netlink.skel.h"
#include "bpf_iter_bpf_map.skel.h"
#include "bpf_iter_tasks.skel.h"
#include "bpf_iter_task_stack.skel.h"
#include "bpf_iter_task_file.skel.h"
#include "bpf_iter_task_vmas.skel.h"
#include "bpf_iter_task_btf.skel.h"
#include "bpf_iter_tcp4.skel.h"
#include "bpf_iter_tcp6.skel.h"
#include "bpf_iter_udp4.skel.h"
#include "bpf_iter_udp6.skel.h"
#include "bpf_iter_unix.skel.h"
#include "bpf_iter_vma_offset.skel.h"
#include "bpf_iter_test_kern1.skel.h"
#include "bpf_iter_test_kern2.skel.h"
#include "bpf_iter_test_kern3.skel.h"
#include "bpf_iter_test_kern4.skel.h"
#include "bpf_iter_bpf_hash_map.skel.h"
#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"
#include "bpf_iter_bpf_link.skel.h"
#include "bpf_iter_ksym.skel.h"
#include "bpf_iter_sockmap.skel.h"
static void test_btf_id_or_null(void)
{
struct bpf_iter_test_kern3 *skel;
skel = bpf_iter_test_kern3__open_and_load();
if (!ASSERT_ERR_PTR(skel, "bpf_iter_test_kern3__open_and_load")) {
bpf_iter_test_kern3__destroy(skel);
return;
}
}
static void do_dummy_read_opts(struct bpf_program *prog, struct bpf_iter_attach_opts *opts)
{
struct bpf_link *link;
char buf[16] = {};
int iter_fd, len;
link = bpf_program__attach_iter(prog, opts);
if (!ASSERT_OK_PTR(link, "attach_iter"))
return;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (!ASSERT_GE(iter_fd, 0, "create_iter"))
goto free_link;
/* not check contents, but ensure read() ends without error */
while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
;
ASSERT_GE(len, 0, "read");
close(iter_fd);
free_link:
bpf_link__destroy(link);
}
static void do_dummy_read(struct bpf_program *prog)
{
do_dummy_read_opts(prog, NULL);
}
static void do_read_map_iter_fd(struct bpf_object_skeleton **skel, struct bpf_program *prog,
struct bpf_map *map)
{
DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
union bpf_iter_link_info linfo;
struct bpf_link *link;
char buf[16] = {};
int iter_fd, len;
memset(&linfo, 0, sizeof(linfo));
linfo.map.map_fd = bpf_map__fd(map);
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
link = bpf_program__attach_iter(prog, &opts);
if (!ASSERT_OK_PTR(link, "attach_map_iter"))
return;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (!ASSERT_GE(iter_fd, 0, "create_map_iter")) {
bpf_link__destroy(link);
return;
}
/* Close link and map fd prematurely */
bpf_link__destroy(link);
bpf_object__destroy_skeleton(*skel);
*skel = NULL;
/* Try to let map free work to run first if map is freed */
usleep(100);
/* Memory used by both sock map and sock local storage map are
* freed after two synchronize_rcu() calls, so wait for it
*/
kern_sync_rcu();
kern_sync_rcu();
/* Read after both map fd and link fd are closed */
while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
;
ASSERT_GE(len, 0, "read_iterator");
close(iter_fd);
}
static int read_fd_into_buffer(int fd, char *buf, int size)
{
int bufleft = size;
int len;
do {
len = read(fd, buf, bufleft);
if (len > 0) {
buf += len;
bufleft -= len;
}
} while (len > 0);
return len < 0 ? len : size - bufleft;
}
static void test_ipv6_route(void)
{
struct bpf_iter_ipv6_route *skel;
skel = bpf_iter_ipv6_route__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_ipv6_route__open_and_load"))
return;
do_dummy_read(skel->progs.dump_ipv6_route);
bpf_iter_ipv6_route__destroy(skel);
}
static void test_netlink(void)
{
struct bpf_iter_netlink *skel;
skel = bpf_iter_netlink__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_netlink__open_and_load"))
return;
do_dummy_read(skel->progs.dump_netlink);
bpf_iter_netlink__destroy(skel);
}
static void test_bpf_map(void)
{
struct bpf_iter_bpf_map *skel;
skel = bpf_iter_bpf_map__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_map__open_and_load"))
return;
do_dummy_read(skel->progs.dump_bpf_map);
bpf_iter_bpf_map__destroy(skel);
}
static void check_bpf_link_info(const struct bpf_program *prog)
{
LIBBPF_OPTS(bpf_iter_attach_opts, opts);
union bpf_iter_link_info linfo;
struct bpf_link_info info = {};
struct bpf_link *link;
__u32 info_len;
int err;
memset(&linfo, 0, sizeof(linfo));
linfo.task.tid = getpid();
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
link = bpf_program__attach_iter(prog, &opts);
if (!ASSERT_OK_PTR(link, "attach_iter"))
return;
info_len = sizeof(info);
err = bpf_link_get_info_by_fd(bpf_link__fd(link), &info, &info_len);
ASSERT_OK(err, "bpf_link_get_info_by_fd");
ASSERT_EQ(info.iter.task.tid, getpid(), "check_task_tid");
bpf_link__destroy(link);
}
static pthread_mutex_t do_nothing_mutex;
static void *do_nothing_wait(void *arg)
{
pthread_mutex_lock(&do_nothing_mutex);
pthread_mutex_unlock(&do_nothing_mutex);
pthread_exit(arg);
}
static void test_task_common_nocheck(struct bpf_iter_attach_opts *opts,
int *num_unknown, int *num_known)
{
struct bpf_iter_tasks *skel;
pthread_t thread_id;
void *ret;
skel = bpf_iter_tasks__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_tasks__open_and_load"))
return;
ASSERT_OK(pthread_mutex_lock(&do_nothing_mutex), "pthread_mutex_lock");
ASSERT_OK(pthread_create(&thread_id, NULL, &do_nothing_wait, NULL),
"pthread_create");
skel->bss->tid = sys_gettid();
do_dummy_read_opts(skel->progs.dump_task, opts);
*num_unknown = skel->bss->num_unknown_tid;
*num_known = skel->bss->num_known_tid;
ASSERT_OK(pthread_mutex_unlock(&do_nothing_mutex), "pthread_mutex_unlock");
ASSERT_FALSE(pthread_join(thread_id, &ret) || ret != NULL,
"pthread_join");
bpf_iter_tasks__destroy(skel);
}
static void test_task_common(struct bpf_iter_attach_opts *opts, int num_unknown, int num_known)
{
int num_unknown_tid, num_known_tid;
test_task_common_nocheck(opts, &num_unknown_tid, &num_known_tid);
ASSERT_EQ(num_unknown_tid, num_unknown, "check_num_unknown_tid");
ASSERT_EQ(num_known_tid, num_known, "check_num_known_tid");
}
static void *run_test_task_tid(void *arg)
{
LIBBPF_OPTS(bpf_iter_attach_opts, opts);
union bpf_iter_link_info linfo;
int num_unknown_tid, num_known_tid;
ASSERT_NEQ(getpid(), sys_gettid(), "check_new_thread_id");
memset(&linfo, 0, sizeof(linfo));
linfo.task.tid = sys_gettid();
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
test_task_common(&opts, 0, 1);
linfo.task.tid = 0;
linfo.task.pid = getpid();
/* This includes the parent thread, this thread, watchdog timer thread
* and the do_nothing_wait thread
*/
test_task_common(&opts, 3, 1);
test_task_common_nocheck(NULL, &num_unknown_tid, &num_known_tid);
ASSERT_GT(num_unknown_tid, 2, "check_num_unknown_tid");
ASSERT_EQ(num_known_tid, 1, "check_num_known_tid");
return NULL;
}
static void test_task_tid(void)
{
pthread_t thread_id;
/* Create a new thread so pid and tid aren't the same */
ASSERT_OK(pthread_create(&thread_id, NULL, &run_test_task_tid, NULL),
"pthread_create");
ASSERT_FALSE(pthread_join(thread_id, NULL), "pthread_join");
}
static void test_task_pid(void)
{
LIBBPF_OPTS(bpf_iter_attach_opts, opts);
union bpf_iter_link_info linfo;
memset(&linfo, 0, sizeof(linfo));
linfo.task.pid = getpid();
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
test_task_common(&opts, 2, 1);
}
static void test_task_pidfd(void)
{
LIBBPF_OPTS(bpf_iter_attach_opts, opts);
union bpf_iter_link_info linfo;
int pidfd;
pidfd = sys_pidfd_open(getpid(), 0);
if (!ASSERT_GT(pidfd, 0, "sys_pidfd_open"))
return;
memset(&linfo, 0, sizeof(linfo));
linfo.task.pid_fd = pidfd;
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
test_task_common(&opts, 2, 1);
close(pidfd);
}
static void test_task_sleepable(void)
{
struct bpf_iter_tasks *skel;
int pid, status, err, data_pipe[2], finish_pipe[2], c;
char *test_data = NULL;
char *test_data_long = NULL;
char *data[2];
if (!ASSERT_OK(pipe(data_pipe), "data_pipe") ||
!ASSERT_OK(pipe(finish_pipe), "finish_pipe"))
return;
skel = bpf_iter_tasks__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_tasks__open_and_load"))
return;
pid = fork();
if (!ASSERT_GE(pid, 0, "fork"))
return;
if (pid == 0) {
/* child */
close(data_pipe[0]);
close(finish_pipe[1]);
test_data = malloc(sizeof(char) * 10);
strncpy(test_data, "test_data", 10);
test_data[9] = '\0';
test_data_long = malloc(sizeof(char) * 5000);
for (int i = 0; i < 5000; ++i) {
if (i % 2 == 0)
test_data_long[i] = 'b';
else
test_data_long[i] = 'a';
}
test_data_long[4999] = '\0';
data[0] = test_data;
data[1] = test_data_long;
write(data_pipe[1], &data, sizeof(data));
/* keep child alive until after the test */
err = read(finish_pipe[0], &c, 1);
if (err != 1)
exit(-1);
close(data_pipe[1]);
close(finish_pipe[0]);
_exit(0);
}
/* parent */
close(data_pipe[1]);
close(finish_pipe[0]);
err = read(data_pipe[0], &data, sizeof(data));
ASSERT_EQ(err, sizeof(data), "read_check");
skel->bss->user_ptr = data[0];
skel->bss->user_ptr_long = data[1];
skel->bss->pid = pid;
do_dummy_read(skel->progs.dump_task_sleepable);
ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task, 0,
"num_expected_failure_copy_from_user_task");
ASSERT_GT(skel->bss->num_success_copy_from_user_task, 0,
"num_success_copy_from_user_task");
ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task_str, 0,
"num_expected_failure_copy_from_user_task_str");
ASSERT_GT(skel->bss->num_success_copy_from_user_task_str, 0,
"num_success_copy_from_user_task_str");
bpf_iter_tasks__destroy(skel);
write(finish_pipe[1], &c, 1);
err = waitpid(pid, &status, 0);
ASSERT_EQ(err, pid, "waitpid");
ASSERT_EQ(status, 0, "zero_child_exit");
close(data_pipe[0]);
close(finish_pipe[1]);
}
static void test_task_stack(void)
{
struct bpf_iter_task_stack *skel;
skel = bpf_iter_task_stack__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_task_stack__open_and_load"))
return;
do_dummy_read(skel->progs.dump_task_stack);
do_dummy_read(skel->progs.get_task_user_stacks);
ASSERT_EQ(skel->bss->num_user_stacks, 1, "num_user_stacks");
bpf_iter_task_stack__destroy(skel);
}
static void test_task_file(void)
{
LIBBPF_OPTS(bpf_iter_attach_opts, opts);
struct bpf_iter_task_file *skel;
union bpf_iter_link_info linfo;
pthread_t thread_id;
void *ret;
skel = bpf_iter_task_file__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_task_file__open_and_load"))
return;
skel->bss->tgid = getpid();
ASSERT_OK(pthread_mutex_lock(&do_nothing_mutex), "pthread_mutex_lock");
ASSERT_OK(pthread_create(&thread_id, NULL, &do_nothing_wait, NULL),
"pthread_create");
memset(&linfo, 0, sizeof(linfo));
linfo.task.tid = getpid();
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
do_dummy_read_opts(skel->progs.dump_task_file, &opts);
ASSERT_EQ(skel->bss->count, 0, "check_count");
ASSERT_EQ(skel->bss->unique_tgid_count, 1, "check_unique_tgid_count");
skel->bss->last_tgid = 0;
skel->bss->count = 0;
skel->bss->unique_tgid_count = 0;
do_dummy_read(skel->progs.dump_task_file);
ASSERT_EQ(skel->bss->count, 0, "check_count");
ASSERT_GT(skel->bss->unique_tgid_count, 1, "check_unique_tgid_count");
check_bpf_link_info(skel->progs.dump_task_file);
ASSERT_OK(pthread_mutex_unlock(&do_nothing_mutex), "pthread_mutex_unlock");
ASSERT_OK(pthread_join(thread_id, &ret), "pthread_join");
ASSERT_NULL(ret, "pthread_join");
bpf_iter_task_file__destroy(skel);
}
#define TASKBUFSZ 32768
static char taskbuf[TASKBUFSZ];
static int do_btf_read(struct bpf_iter_task_btf *skel)
{
struct bpf_program *prog = skel->progs.dump_task_struct;
struct bpf_iter_task_btf__bss *bss = skel->bss;
int iter_fd = -1, err;
struct bpf_link *link;
char *buf = taskbuf;
int ret = 0;
link = bpf_program__attach_iter(prog, NULL);
if (!ASSERT_OK_PTR(link, "attach_iter"))
return ret;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (!ASSERT_GE(iter_fd, 0, "create_iter"))
goto free_link;
err = read_fd_into_buffer(iter_fd, buf, TASKBUFSZ);
if (bss->skip) {
printf("%s:SKIP:no __builtin_btf_type_id\n", __func__);
ret = 1;
test__skip();
goto free_link;
}
if (!ASSERT_GE(err, 0, "read"))
goto free_link;
ASSERT_HAS_SUBSTR(taskbuf, "(struct task_struct)",
"check for btf representation of task_struct in iter data");
free_link:
if (iter_fd > 0)
close(iter_fd);
bpf_link__destroy(link);
return ret;
}
static void test_task_btf(void)
{
struct bpf_iter_task_btf__bss *bss;
struct bpf_iter_task_btf *skel;
int ret;
skel = bpf_iter_task_btf__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_task_btf__open_and_load"))
return;
bss = skel->bss;
ret = do_btf_read(skel);
if (ret)
goto cleanup;
if (!ASSERT_NEQ(bss->tasks, 0, "no task iteration, did BPF program run?"))
goto cleanup;
ASSERT_EQ(bss->seq_err, 0, "check for unexpected err");
cleanup:
bpf_iter_task_btf__destroy(skel);
}
static void test_tcp4(void)
{
struct bpf_iter_tcp4 *skel;
skel = bpf_iter_tcp4__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_tcp4__open_and_load"))
return;
do_dummy_read(skel->progs.dump_tcp4);
bpf_iter_tcp4__destroy(skel);
}
static void test_tcp6(void)
{
struct bpf_iter_tcp6 *skel;
skel = bpf_iter_tcp6__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_tcp6__open_and_load"))
return;
do_dummy_read(skel->progs.dump_tcp6);
bpf_iter_tcp6__destroy(skel);
}
static void test_udp4(void)
{
struct bpf_iter_udp4 *skel;
skel = bpf_iter_udp4__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_udp4__open_and_load"))
return;
do_dummy_read(skel->progs.dump_udp4);
bpf_iter_udp4__destroy(skel);
}
static void test_udp6(void)
{
struct bpf_iter_udp6 *skel;
skel = bpf_iter_udp6__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_udp6__open_and_load"))
return;
do_dummy_read(skel->progs.dump_udp6);
bpf_iter_udp6__destroy(skel);
}
static void test_unix(void)
{
struct bpf_iter_unix *skel;
skel = bpf_iter_unix__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_unix__open_and_load"))
return;
do_dummy_read(skel->progs.dump_unix);
bpf_iter_unix__destroy(skel);
}
/* The expected string is less than 16 bytes */
static int do_read_with_fd(int iter_fd, const char *expected,
bool read_one_char)
{
int len, read_buf_len, start;
char buf[16] = {};
read_buf_len = read_one_char ? 1 : 16;
start = 0;
while ((len = read(iter_fd, buf + start, read_buf_len)) > 0) {
start += len;
if (!ASSERT_LT(start, 16, "read"))
return -1;
read_buf_len = read_one_char ? 1 : 16 - start;
}
if (!ASSERT_GE(len, 0, "read"))
return -1;
if (!ASSERT_STREQ(buf, expected, "read"))
return -1;
return 0;
}
static void test_anon_iter(bool read_one_char)
{
struct bpf_iter_test_kern1 *skel;
struct bpf_link *link;
int iter_fd, err;
skel = bpf_iter_test_kern1__open_and_load();
if (!ASSERT_OK_PTR(skel, "bpf_iter_test_kern1__open_and_load"))
return;
err = bpf_iter_test_kern1__attach(skel);
if (!ASSERT_OK(err, "bpf_iter_test_kern1__attach")) {
goto out;
}
link = skel->links.dump_task;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (!ASSERT_GE(iter_fd, 0, "create_iter"))
goto out;
do_read_with_fd(iter_fd, "abcd", read_one_char);
close(iter_fd);
out:
bpf_iter_test_kern1__destroy(skel);
}
static int do_read(const char *path, const char *expected)
{
int err, iter_fd;
iter_fd = open(path, O_RDONLY);
if (!ASSERT_GE(iter_fd, 0, "open"))
return -1;
err = do_read_with_fd(iter_fd, expected, false);
close(iter_fd);
return err;
}
static void test_file_iter(void)
{
const char *path = "/sys/fs/bpf/bpf_iter_test1";
struct bpf_iter_test_kern1 *skel1;
struct bpf_iter_test_kern2 *skel2;
struct bpf_link *link;
int err;
skel1 = bpf_iter_test_kern1__open_and_load();
if (!ASSERT_OK_PTR(skel1, "bpf_iter_test_kern1__open_and_load"))
return;
link = bpf_program__attach_iter(skel1->progs.dump_task, NULL);
if (!ASSERT_OK_PTR(link, "attach_iter"))
goto out;
/* unlink this path if it exists. */
unlink(path);
err = bpf_link__pin(link, path);
if (!ASSERT_OK(err, "pin_iter"))
goto free_link;
err = do_read(path, "abcd");
if (err)
goto unlink_path;
/* file based iterator seems working fine. Let us a link update
* of the underlying link and `cat` the iterator again, its content
* should change.
*/
skel2 = bpf_iter_test_kern2__open_and_load();
if (!ASSERT_OK_PTR(skel2, "bpf_iter_test_kern2__open_and_load"))
goto unlink_path;
err = bpf_link__update_program(link, skel2->progs.dump_task);
if (!ASSERT_OK(err, "update_prog"))
goto destroy_skel2;
do_read(path, "ABCD");
destroy_skel2:
bpf_iter_test_kern2__destroy(skel2);
unlink_path:
unlink(path);
free_link:
bpf_link__destroy(link);
out:
bpf_iter_test_kern1__destroy(skel1);
}
static void test_overflow(bool test_e2big_overflow, bool ret1)
{
__u32 map_info_len, total_read_len, expected_read_len;
int err, iter_fd, map1_fd, map2_fd, len;
struct bpf_map_info map_info = {};
struct bpf_iter_test_kern4 *skel;
struct bpf_link *link;
__u32 iter_size;
char *buf;
skel = bpf_iter_test_kern4__open();
if (!ASSERT_OK_PTR(skel, "bpf_iter_test_kern4__open"))
return;
/* create two maps: bpf program will only do bpf_seq_write
* for these two maps. The goal is one map output almost
* fills seq_file buffer and then the other will trigger
* overflow and needs restart.
*/
map1_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, 4, 8, 1, NULL);
if (!ASSERT_GE(map1_fd, 0, "bpf_map_create"))
goto out;
map2_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, 4, 8, 1, NULL);
if (!ASSERT_GE(map2_fd, 0, "bpf_map_create"))
goto free_map1;
/* bpf_seq_printf kernel buffer is 8 pages, so one map
* bpf_seq_write will mostly fill it, and the other map
* will partially fill and then trigger overflow and need
* bpf_seq_read restart.
*/
iter_size = sysconf(_SC_PAGE_SIZE) << 3;
if (test_e2big_overflow) {
skel->rodata->print_len = (iter_size + 8) / 8;
expected_read_len = 2 * (iter_size + 8);
} else if (!ret1) {
skel->rodata->print_len = (iter_size - 8) / 8;
expected_read_len = 2 * (iter_size - 8);
} else {
skel->rodata->print_len = 1;
expected_read_len = 2 * 8;
}
skel->rodata->ret1 = ret1;
if (!ASSERT_OK(bpf_iter_test_kern4__load(skel),
"bpf_iter_test_kern4__load"))
goto free_map2;
/* setup filtering map_id in bpf program */
map_info_len = sizeof(map_info);
err = bpf_map_get_info_by_fd(map1_fd, &map_info, &map_info_len);
if (!ASSERT_OK(err, "get_map_info"))
goto free_map2;
skel->bss->map1_id = map_info.id;
err = bpf_map_get_info_by_fd(map2_fd, &map_info, &map_info_len);
if (!ASSERT_OK(err, "get_map_info"))
goto free_map2;
skel->bss->map2_id = map_info.id;
link = bpf_program__attach_iter(skel->progs.dump_bpf_map, NULL);
if (!ASSERT_OK_PTR(link, "attach_iter"))
goto free_map2;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (!ASSERT_GE(iter_fd, 0, "create_iter"))
goto free_link;
buf = malloc(expected_read_len);
if (!ASSERT_OK_PTR(buf, "malloc"))
goto close_iter;
/* do read */
total_read_len = 0;
if (test_e2big_overflow) {
while ((len = read(iter_fd, buf, expected_read_len)) > 0)
total_read_len += len;
ASSERT_EQ(len, -1, "read");
ASSERT_EQ(errno, E2BIG, "read");
goto free_buf;
} else if (!ret1) {
while ((len = read(iter_fd, buf, expected_read_len)) > 0)
total_read_len += len;
if (!ASSERT_GE(len, 0, "read"))
goto free_buf;
} else {
do {
len = read(iter_fd, buf, expected_read_len);
if (len > 0)
total_read_len += len;
} while (len > 0 || len == -EAGAIN);
if (!ASSERT_GE(len, 0, "read"))
goto free_buf;
}
if (!ASSERT_EQ(total_read_len, expected_read_len, "read"))
goto free_buf;
if (!ASSERT_EQ(skel->bss->map1_accessed, 1, "map1_accessed"))
goto free_buf;
if (!ASSERT_EQ(skel->bss->map2_accessed, 2, "map2_accessed"))
goto free_buf;
ASSERT_EQ(skel->bss->map2_seqnum1, skel->bss->map2_seqnum2, "map2_seqnum");
free_buf:
free(buf);
close_iter:
close(iter_fd);
free_link:
bpf_link__destroy(link);
free_map2:
close(map2_fd);
free_map1:
close(map1_fd);
out:
bpf_iter_test_kern4__destroy(skel);
}
static void test_bpf_hash_map(void)
{
__u32 expected_key_a = 0, expected_key_b = 0;
DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
struct bpf_iter_bpf_hash_map *skel;
int err, i, len, map_fd, iter_fd;
union bpf_iter_link_info linfo;
__u64 val, expected_val = 0;
struct bpf_link *link;
struct key_t {
int a;
int b;
int c;
} key;
char buf[64];
skel = bpf_iter_bpf_hash_map__open();
if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_hash_map__open"))
return;
skel->bss->in_test_mode = true;
err = bpf_iter_bpf_hash_map__load(skel);
if (!ASSERT_OK(err, "bpf_iter_bpf_hash_map__load"))
goto out;
/* iterator with hashmap2 and hashmap3 should fail */
memset(&linfo, 0, sizeof(linfo));
linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap2);
opts.link_info = &linfo;
opts.link_info_len = sizeof(linfo);
link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts);
if (!ASSERT_ERR_PTR(link, "attach_iter"))
goto out;
linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap3);
link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts);
if (!ASSERT_ERR_PTR(link, "attach_iter"))
goto out;
/* hashmap1 should be good, update map values here */
map_fd = bpf_map__fd(skel->maps.hashmap1);
for (i = 0; i < bpf_map__max_entries(skel->maps.hashmap1); i++) {
key.a = i + 1;
key.b = i + 2;
key.c = i + 3;
val = i + 4;
expected_key_a += key.a;
expected_key_b += key.b;
expected_val += val;
err = bpf_map_update_elem(map_fd, &key, &val, BPF_ANY);
if (!ASSERT_OK(err, "map_update"))
goto out;
}
/* Sleepable program is prohibited for hash map iterator */
linfo.map.map_fd = map_fd;
link = bpf_program__attach_iter(skel->progs.sleepable_dummy_dump, &opts);
if (!ASSERT_ERR_PTR(link, "attach_sleepable_prog_to_iter"))
goto out;
linfo.map.map_fd = map_fd;
link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts);
if (!ASSERT_OK_PTR(link, "attach_iter"))
goto out;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (!ASSERT_GE(iter_fd, 0, "create_iter"))
goto free_link;
/* do some tests */
while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
;
if (!ASSERT_GE(len, 0, "read"))
goto close_iter;
/* test results */
if (!ASSERT_EQ(skel->bss->key_sum_a, expected_key_a, "key_sum_a"))
goto close_iter;
if (!ASSERT_EQ(skel->bss->key_sum_b, expected_key_b, "key_sum_b"))
goto close_iter;
if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
goto close_iter;
close_iter:
close(iter_fd);
free_link:
bpf_link__destroy(link);
out:
bpf_iter_bpf_hash_map__destroy(skel);
}
static void test_bpf_percpu_hash_map(void)
{
__u32 expected_key_a = 0, expected_key_b = 0;
DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
struct bpf_iter_bpf_percpu_hash_map *skel;
int err, i, j, len, map_fd, iter_fd;
union bpf_iter_link_info linfo;
__u32 expected_val = 0;
struct bpf_link *link;
struct key_t {
int a;
int b;
int c;
} key;
char buf[64];
void *val;
skel = bpf_iter_bpf_percpu_hash_map__open();
if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_hash_map__open"))
return;
skel->rodata->num_cpus = bpf_num_possible_cpus();
val = malloc(8 * bpf_num_possible_cpus());
if (!ASSERT_OK_PTR(val, "malloc"))
goto out;
err = bpf_iter_bpf_percpu_hash_map__load(skel);
if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_hash_map__load"))
goto out;
/* update map values here */
map_fd = bpf_map__fd(skel->maps.hashmap1);
for (i = 0; i < bpf_map__max_entries(skel->maps.hashmap1); i++) {
key.a = i + 1;
key.b = i + 2;
key.c = i + 3;
expected_key_a += key.a;
expected_key_b += key.b;
for (j = 0; j < bpf_num_possible_cpus(); j++) {
*(__u32 *)(val + j * 8) = i + j;
expected_val += i + j;
}
err = bpf_map_update_elem(map_fd, &key, val, BPF_ANY);
if (!ASSERT_OK(err, "map_update"))
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.dump_bpf_percpu_hash_map, &opts);
if (!ASSERT_OK_PTR(link, "attach_iter"))
goto out;
iter_fd = bpf_iter_create(bpf_link__fd(link));
if (!ASSERT_GE(iter_fd, 0, "create_iter"))
goto free_link;
/* do some tests */
while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
;
if (!ASSERT_GE(len, 0, "read"))
goto close_iter;