// 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 = 0;
        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);
                strscpy(test_data, "test_data", 10);

                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;

        /* 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_percpu_hash_map__destroy(skel);
        free(val);
}

static void test_bpf_array_map(void)
{
        __u64 val, expected_val = 0, res_first_val, first_val = 0;
        DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
        __u32 key, expected_key = 0, res_first_key;
        int err, i, map_fd, hash_fd, iter_fd;
        struct bpf_iter_bpf_array_map *skel;
        union bpf_iter_link_info linfo;
        struct bpf_link *link;
        char buf[64] = {};
        int len, start;

        skel = bpf_iter_bpf_array_map__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_array_map__open_and_load"))
                return;

        map_fd = bpf_map__fd(skel->maps.arraymap1);
        for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {
                val = i + 4;
                expected_key += i;
                expected_val += val;

                if (i == 0)
                        first_val = val;

                err = bpf_map_update_elem(map_fd, &i, &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_array_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 */
        start = 0;
        while ((len = read(iter_fd, buf + start, sizeof(buf) - start)) > 0)
                start += len;
        if (!ASSERT_GE(len, 0, "read"))
                goto close_iter;

        /* test results */
        res_first_key = *(__u32 *)buf;
        res_first_val = *(__u64 *)(buf + sizeof(__u32));
        if (!ASSERT_EQ(res_first_key, 0, "bpf_seq_write") ||
                        !ASSERT_EQ(res_first_val, first_val, "bpf_seq_write"))
                goto close_iter;

        if (!ASSERT_EQ(skel->bss->key_sum, expected_key, "key_sum"))
                goto close_iter;
        if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
                goto close_iter;

        hash_fd = bpf_map__fd(skel->maps.hashmap1);
        for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {
                err = bpf_map_lookup_elem(map_fd, &i, &val);
                if (!ASSERT_OK(err, "map_lookup arraymap1"))
                        goto close_iter;
                if (!ASSERT_EQ(i, val, "invalid_val arraymap1"))
                        goto close_iter;

                val = i + 4;
                err = bpf_map_lookup_elem(hash_fd, &val, &key);
                if (!ASSERT_OK(err, "map_lookup hashmap1"))
                        goto close_iter;
                if (!ASSERT_EQ(key, val - 4, "invalid_val hashmap1"))
                        goto close_iter;
        }

close_iter:
        close(iter_fd);
free_link:
        bpf_link__destroy(link);
out:
        bpf_iter_bpf_array_map__destroy(skel);
}

static void test_bpf_array_map_iter_fd(void)
{
        struct bpf_iter_bpf_array_map *skel;

        skel = bpf_iter_bpf_array_map__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_array_map__open_and_load"))
                return;

        do_read_map_iter_fd(&skel->skeleton, skel->progs.dump_bpf_array_map,
                            skel->maps.arraymap1);

        bpf_iter_bpf_array_map__destroy(skel);
}

static void test_bpf_percpu_array_map(void)
{
        DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
        struct bpf_iter_bpf_percpu_array_map *skel;
        __u32 expected_key = 0, expected_val = 0;
        union bpf_iter_link_info linfo;
        int err, i, j, map_fd, iter_fd;
        struct bpf_link *link;
        char buf[64];
        void *val;
        int len;

        skel = bpf_iter_bpf_percpu_array_map__open();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_array_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_array_map__load(skel);
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_array_map__load"))
                goto out;

        /* update map values here */
        map_fd = bpf_map__fd(skel->maps.arraymap1);
        for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {
                expected_key += i;

                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, &i, 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_array_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, expected_key, "key_sum"))
                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_percpu_array_map__destroy(skel);
        free(val);
}

/* 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 (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_helpers__open_and_load"))
                return;

        map_fd = bpf_map__fd(skel->maps.sk_stg_map);

        sock_fd = socket(AF_INET6, SOCK_STREAM, 0);
        if (!ASSERT_GE(sock_fd, 0, "socket"))
                goto out;

        err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST);
        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.delete_bpf_sk_storage_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 */
        err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);

         /* Note: The following assertions serve to ensure
          * the value was deleted. It does so by asserting
          * that bpf_map_lookup_elem has failed. This might
          * seem counterintuitive at first.
          */
        ASSERT_ERR(err, "bpf_map_lookup_elem");
        ASSERT_EQ(errno, ENOENT, "bpf_map_lookup_elem");

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);
}

/* This creates a socket and its local storage. It then runs a task_iter BPF
 * program that replaces the existing socket local storage with the tgid of the
 * only task owning a file descriptor to this socket, this process, prog_tests.
 * It then runs a tcp socket iterator that negates the value in the existing
 * socket local storage, the test verifies that the resulting value is -pid.
 */
static void test_bpf_sk_storage_get(void)
{
        struct bpf_iter_bpf_sk_storage_helpers *skel;
        int err, map_fd, val = -1;
        int sock_fd = -1;

        skel = bpf_iter_bpf_sk_storage_helpers__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_helpers__open_and_load"))
                return;

        sock_fd = socket(AF_INET6, SOCK_STREAM, 0);
        if (!ASSERT_GE(sock_fd, 0, "socket"))
                goto out;

        err = listen(sock_fd, 1);
        if (!ASSERT_OK(err, "listen"))
                goto close_socket;

        map_fd = bpf_map__fd(skel->maps.sk_stg_map);

        err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST);
        if (!ASSERT_OK(err, "bpf_map_update_elem"))
                goto close_socket;

        do_dummy_read(skel->progs.fill_socket_owner);

        err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
        if (!ASSERT_OK(err, "bpf_map_lookup_elem") ||
                        !ASSERT_EQ(val, getpid(), "bpf_map_lookup_elem"))
                goto close_socket;

        do_dummy_read(skel->progs.negate_socket_local_storage);

        err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
        ASSERT_OK(err, "bpf_map_lookup_elem");
        ASSERT_EQ(val, -getpid(), "bpf_map_lookup_elem");

close_socket:
        close(sock_fd);
out:
        bpf_iter_bpf_sk_storage_helpers__destroy(skel);
}

static void test_bpf_sk_storage_map_iter_fd(void)
{
        struct bpf_iter_bpf_sk_storage_map *skel;

        skel = bpf_iter_bpf_sk_storage_map__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_map__open_and_load"))
                return;

        do_read_map_iter_fd(&skel->skeleton, skel->progs.rw_bpf_sk_storage_map,
                            skel->maps.sk_stg_map);

        bpf_iter_bpf_sk_storage_map__destroy(skel);
}

static void test_bpf_sk_storage_map(void)
{
        DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
        int err, i, len, map_fd, iter_fd, num_sockets;
        struct bpf_iter_bpf_sk_storage_map *skel;
        union bpf_iter_link_info linfo;
        int sock_fd[3] = {-1, -1, -1};
        __u32 val, expected_val = 0;
        struct bpf_link *link;
        char buf[64];

        skel = bpf_iter_bpf_sk_storage_map__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_map__open_and_load"))
                return;

        map_fd = bpf_map__fd(skel->maps.sk_stg_map);
        num_sockets = ARRAY_SIZE(sock_fd);
        for (i = 0; i < num_sockets; i++) {
                sock_fd[i] = socket(AF_INET6, SOCK_STREAM, 0);
                if (!ASSERT_GE(sock_fd[i], 0, "socket"))
                        goto out;

                val = i + 1;
                expected_val += val;

                err = bpf_map_update_elem(map_fd, &sock_fd[i], &val,
                                          BPF_NOEXIST);
                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.oob_write_bpf_sk_storage_map, &opts);
        err = libbpf_get_error(link);
        if (!ASSERT_EQ(err, -EACCES, "attach_oob_write_iter")) {
                if (!err)
                        bpf_link__destroy(link);
                goto out;
        }

        link = bpf_program__attach_iter(skel->progs.rw_bpf_sk_storage_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;

        skel->bss->to_add_val = time(NULL);
        /* 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->ipv6_sk_count, num_sockets, "ipv6_sk_count"))
                goto close_iter;

        if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
                goto close_iter;

        for (i = 0; i < num_sockets; i++) {
                err = bpf_map_lookup_elem(map_fd, &sock_fd[i], &val);
                if (!ASSERT_OK(err, "map_lookup") ||
                    !ASSERT_EQ(val, i + 1 + skel->bss->to_add_val, "check_map_value"))
                        break;
        }

close_iter:
        close(iter_fd);
free_link:
        bpf_link__destroy(link);
out:
        for (i = 0; i < num_sockets; i++) {
                if (sock_fd[i] >= 0)
                        close(sock_fd[i]);
        }
        bpf_iter_bpf_sk_storage_map__destroy(skel);
}

static void test_rdonly_buf_out_of_bound(void)
{
        DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
        struct bpf_iter_test_kern5 *skel;
        union bpf_iter_link_info linfo;
        struct bpf_link *link;

        skel = bpf_iter_test_kern5__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_test_kern5__open_and_load"))
                return;

        memset(&linfo, 0, sizeof(linfo));
        linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap1);
        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"))
                bpf_link__destroy(link);

        bpf_iter_test_kern5__destroy(skel);
}

static void test_buf_neg_offset(void)
{
        struct bpf_iter_test_kern6 *skel;

        skel = bpf_iter_test_kern6__open_and_load();
        if (!ASSERT_ERR_PTR(skel, "bpf_iter_test_kern6__open_and_load"))
                bpf_iter_test_kern6__destroy(skel);
}

static void test_link_iter(void)
{
        struct bpf_iter_bpf_link *skel;

        skel = bpf_iter_bpf_link__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_link__open_and_load"))
                return;

        do_dummy_read(skel->progs.dump_bpf_link);

        bpf_iter_bpf_link__destroy(skel);
}

static void test_ksym_iter(void)
{
        struct bpf_iter_ksym *skel;

        skel = bpf_iter_ksym__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_ksym__open_and_load"))
                return;

        do_dummy_read(skel->progs.dump_ksym);

        bpf_iter_ksym__destroy(skel);
}

#define CMP_BUFFER_SIZE 1024
static char task_vma_output[CMP_BUFFER_SIZE];
static char proc_maps_output[CMP_BUFFER_SIZE];

/* remove \0 and \t from str, and only keep the first line */
static void str_strip_first_line(char *str)
{
        char *dst = str, *src = str;

        do {
                if (*src == ' ' || *src == '\t')
                        src++;
                else
                        *(dst++) = *(src++);

        } while (*src != '\0' && *src != '\n');

        *dst = '\0';
}

static void test_task_vma_common(struct bpf_iter_attach_opts *opts)
{
        int err, iter_fd = -1, proc_maps_fd = -1;
        struct bpf_iter_task_vmas *skel;
        int len, read_size = 4;
        char maps_path[64];

        skel = bpf_iter_task_vmas__open();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_task_vmas__open"))
                return;

        skel->bss->pid = getpid();
        skel->bss->one_task = opts ? 1 : 0;

        err = bpf_iter_task_vmas__load(skel);
        if (!ASSERT_OK(err, "bpf_iter_task_vmas__load"))
                goto out;

        skel->links.proc_maps = bpf_program__attach_iter(
                skel->progs.proc_maps, opts);

        if (!ASSERT_OK_PTR(skel->links.proc_maps, "bpf_program__attach_iter")) {
                skel->links.proc_maps = NULL;
                goto out;
        }

        iter_fd = bpf_iter_create(bpf_link__fd(skel->links.proc_maps));
        if (!ASSERT_GE(iter_fd, 0, "create_iter"))
                goto out;

        /* Read CMP_BUFFER_SIZE (1kB) from bpf_iter. Read in small chunks
         * to trigger seq_file corner cases.
         */
        len = 0;
        while (len < CMP_BUFFER_SIZE) {
                err = read_fd_into_buffer(iter_fd, task_vma_output + len,
                                          MIN(read_size, CMP_BUFFER_SIZE - len));
                if (!err)
                        break;
                if (!ASSERT_GE(err, 0, "read_iter_fd"))
                        goto out;
                len += err;
        }
        if (opts)
                ASSERT_EQ(skel->bss->one_task_error, 0, "unexpected task");

        /* read CMP_BUFFER_SIZE (1kB) from /proc/pid/maps */
        snprintf(maps_path, 64, "/proc/%u/maps", skel->bss->pid);
        proc_maps_fd = open(maps_path, O_RDONLY);
        if (!ASSERT_GE(proc_maps_fd, 0, "open_proc_maps"))
                goto out;
        err = read_fd_into_buffer(proc_maps_fd, proc_maps_output, CMP_BUFFER_SIZE);
        if (!ASSERT_GE(err, 0, "read_prog_maps_fd"))
                goto out;

        /* strip and compare the first line of the two files */
        str_strip_first_line(task_vma_output);
        str_strip_first_line(proc_maps_output);

        ASSERT_STREQ(task_vma_output, proc_maps_output, "compare_output");

        check_bpf_link_info(skel->progs.proc_maps);

out:
        close(proc_maps_fd);
        close(iter_fd);
        bpf_iter_task_vmas__destroy(skel);
}

static void test_task_vma_dead_task(void)
{
        struct bpf_iter_task_vmas *skel;
        int wstatus, child_pid = -1;
        time_t start_tm, cur_tm;
        int err, iter_fd = -1;
        int wait_sec = 3;

        skel = bpf_iter_task_vmas__open();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_task_vmas__open"))
                return;

        skel->bss->pid = getpid();

        err = bpf_iter_task_vmas__load(skel);
        if (!ASSERT_OK(err, "bpf_iter_task_vmas__load"))
                goto out;

        skel->links.proc_maps = bpf_program__attach_iter(
                skel->progs.proc_maps, NULL);

        if (!ASSERT_OK_PTR(skel->links.proc_maps, "bpf_program__attach_iter")) {
                skel->links.proc_maps = NULL;
                goto out;
        }

        start_tm = time(NULL);
        cur_tm = start_tm;

        child_pid = fork();
        if (child_pid == 0) {
                /* Fork short-lived processes in the background. */
                while (cur_tm < start_tm + wait_sec) {
                        system("echo > /dev/null");
                        cur_tm = time(NULL);
                }
                exit(0);
        }

        if (!ASSERT_GE(child_pid, 0, "fork_child"))
                goto out;

        while (cur_tm < start_tm + wait_sec) {
                iter_fd = bpf_iter_create(bpf_link__fd(skel->links.proc_maps));
                if (!ASSERT_GE(iter_fd, 0, "create_iter"))
                        goto out;

                /* Drain all data from iter_fd. */
                while (cur_tm < start_tm + wait_sec) {
                        err = read_fd_into_buffer(iter_fd, task_vma_output, CMP_BUFFER_SIZE);
                        if (!ASSERT_GE(err, 0, "read_iter_fd"))
                                goto out;

                        cur_tm = time(NULL);

                        if (err == 0)
                                break;
                }

                close(iter_fd);
                iter_fd = -1;
        }

        check_bpf_link_info(skel->progs.proc_maps);

out:
        waitpid(child_pid, &wstatus, 0);
        close(iter_fd);
        bpf_iter_task_vmas__destroy(skel);
}

void test_bpf_sockmap_map_iter_fd(void)
{
        struct bpf_iter_sockmap *skel;

        skel = bpf_iter_sockmap__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_sockmap__open_and_load"))
                return;

        do_read_map_iter_fd(&skel->skeleton, skel->progs.copy, skel->maps.sockmap);

        bpf_iter_sockmap__destroy(skel);
}

static void test_task_vma(void)
{
        LIBBPF_OPTS(bpf_iter_attach_opts, opts);
        union bpf_iter_link_info linfo;

        memset(&linfo, 0, sizeof(linfo));
        linfo.task.tid = getpid();
        opts.link_info = &linfo;
        opts.link_info_len = sizeof(linfo);

        test_task_vma_common(&opts);
        test_task_vma_common(NULL);
}

/* uprobe attach point */
static noinline int trigger_func(int arg)
{
        asm volatile ("");
        return arg + 1;
}

static void test_task_vma_offset_common(struct bpf_iter_attach_opts *opts, bool one_proc)
{
        struct bpf_iter_vma_offset *skel;
        char buf[16] = {};
        int iter_fd, len;
        int pgsz, shift;

        skel = bpf_iter_vma_offset__open_and_load();
        if (!ASSERT_OK_PTR(skel, "bpf_iter_vma_offset__open_and_load"))
                return;

        skel->bss->pid = getpid();
        skel->bss->address = (uintptr_t)trigger_func;
        for (pgsz = getpagesize(), shift = 0; pgsz > 1; pgsz >>= 1, shift++)
                ;
        skel->bss->page_shift = shift;

        skel->links.get_vma_offset = bpf_program__attach_iter(skel->progs.get_vma_offset, opts);
        if (!ASSERT_OK_PTR(skel->links.get_vma_offset, "attach_iter"))
                goto exit;

        iter_fd = bpf_iter_create(bpf_link__fd(skel->links.get_vma_offset));
        if (!ASSERT_GT(iter_fd, 0, "create_iter"))
                goto exit;

        while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
                ;
        buf[15] = 0;
        ASSERT_EQ(strcmp(buf, "OK\n"), 0, "strcmp");

        ASSERT_EQ(skel->bss->offset, get_uprobe_offset(trigger_func), "offset");
        if (one_proc)
                ASSERT_EQ(skel->bss->unique_tgid_cnt, 1, "unique_tgid_count");
        else
                ASSERT_GT(skel->bss->unique_tgid_cnt, 1, "unique_tgid_count");

        close(iter_fd);

exit:
        bpf_iter_vma_offset__destroy(skel);
}

static void test_task_vma_offset(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_vma_offset_common(&opts, true);

        linfo.task.pid = 0;
        linfo.task.tid = getpid();
        test_task_vma_offset_common(&opts, true);

        test_task_vma_offset_common(NULL, false);
}

void test_bpf_iter(void)
{
        ASSERT_OK(pthread_mutex_init(&do_nothing_mutex, NULL), "pthread_mutex_init");

        if (test__start_subtest("btf_id_or_null"))
                test_btf_id_or_null();
        if (test__start_subtest("ipv6_route"))
                test_ipv6_route();
        if (test__start_subtest("netlink"))
                test_netlink();
        if (test__start_subtest("bpf_map"))
                test_bpf_map();
        if (test__start_subtest("task_tid"))
                test_task_tid();
        if (test__start_subtest("task_pid"))
                test_task_pid();
        if (test__start_subtest("task_pidfd"))
                test_task_pidfd();
        if (test__start_subtest("task_sleepable"))
                test_task_sleepable();
        if (test__start_subtest("task_stack"))
                test_task_stack();
        if (test__start_subtest("task_file"))
                test_task_file();
        if (test__start_subtest("task_vma"))
                test_task_vma();
        if (test__start_subtest("task_vma_dead_task"))
                test_task_vma_dead_task();
        if (test__start_subtest("task_btf"))
                test_task_btf();
        if (test__start_subtest("tcp4"))
                test_tcp4();
        if (test__start_subtest("tcp6"))
                test_tcp6();
        if (test__start_subtest("udp4"))
                test_udp4();
        if (test__start_subtest("udp6"))
                test_udp6();
        if (test__start_subtest("unix"))
                test_unix();
        if (test__start_subtest("anon"))
                test_anon_iter(false);
        if (test__start_subtest("anon-read-one-char"))
                test_anon_iter(true);
        if (test__start_subtest("file"))
                test_file_iter();
        if (test__start_subtest("overflow"))
                test_overflow(false, false);
        if (test__start_subtest("overflow-e2big"))
                test_overflow(true, false);
        if (test__start_subtest("prog-ret-1"))
                test_overflow(false, true);
        if (test__start_subtest("bpf_hash_map"))
                test_bpf_hash_map();
        if (test__start_subtest("bpf_percpu_hash_map"))
                test_bpf_percpu_hash_map();
        if (test__start_subtest("bpf_array_map"))
                test_bpf_array_map();
        if (test__start_subtest("bpf_array_map_iter_fd"))
                test_bpf_array_map_iter_fd();
        if (test__start_subtest("bpf_percpu_array_map"))
                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_map_iter_fd"))
                test_bpf_sk_storage_map_iter_fd();
        if (test__start_subtest("bpf_sk_storage_delete"))
                test_bpf_sk_storage_delete();
        if (test__start_subtest("bpf_sk_storage_get"))
                test_bpf_sk_storage_get();
        if (test__start_subtest("rdonly-buf-out-of-bound"))
                test_rdonly_buf_out_of_bound();
        if (test__start_subtest("buf-neg-offset"))
                test_buf_neg_offset();
        if (test__start_subtest("link-iter"))
                test_link_iter();
        if (test__start_subtest("ksym"))
                test_ksym_iter();
        if (test__start_subtest("bpf_sockmap_map_iter_fd"))
                test_bpf_sockmap_map_iter_fd();
        if (test__start_subtest("vma_offset"))
                test_task_vma_offset();
}