bpf/prog_tests/global_data_init.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #include <test_progs.h>
0003
0004 void test_global_data_init(void)
0005 {
0006     const char *file = "./test_global_data.o";
0007     int err = -ENOMEM, map_fd, zero = 0;
0008     __u8 *buff = NULL, *newval = NULL;
0009     struct bpf_object *obj;
0010     struct bpf_map *map;
0011         __u32 duration = 0;
0012     size_t sz;
0013
0014     obj = bpf_object__open_file(file, NULL);
0015     err = libbpf_get_error(obj);
0016     if (CHECK_FAIL(err))
0017         return;
0018
0019     map = bpf_object__find_map_by_name(obj, ".rodata");
0020     if (CHECK_FAIL(!map || !bpf_map__is_internal(map)))
0021         goto out;
0022
0023     sz = bpf_map__value_size(map);
0024     newval = malloc(sz);
0025     if (CHECK_FAIL(!newval))
0026         goto out;
0027
0028     memset(newval, 0, sz);
0029     /* wrong size, should fail */
0030     err = bpf_map__set_initial_value(map, newval, sz - 1);
0031     if (CHECK(!err, "reject set initial value wrong size", "err %d\n", err))
0032         goto out;
0033
0034     err = bpf_map__set_initial_value(map, newval, sz);
0035     if (CHECK(err, "set initial value", "err %d\n", err))
0036         goto out;
0037
0038     err = bpf_object__load(obj);
0039     if (CHECK_FAIL(err))
0040         goto out;
0041
0042     map_fd = bpf_map__fd(map);
0043     if (CHECK_FAIL(map_fd < 0))
0044         goto out;
0045
0046     buff = malloc(sz);
0047     if (buff)
0048         err = bpf_map_lookup_elem(map_fd, &zero, buff);
0049     if (CHECK(!buff || err || memcmp(buff, newval, sz),
0050           "compare .rodata map data override",
0051           "err %d errno %d\n", err, errno))
0052         goto out;
0053
0054     memset(newval, 1, sz);
0055     /* object loaded - should fail */
0056     err = bpf_map__set_initial_value(map, newval, sz);
0057     CHECK(!err, "reject set initial value after load", "err %d\n", err);
0058 out:
0059     free(buff);
0060     free(newval);
0061     bpf_object__close(obj);
0062 }