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

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <test_progs.h>
   3
   4 void test_global_data_init(void)
   5 {
   6         const char *file = "./test_global_data.o";
   7         int err = -ENOMEM, map_fd, zero = 0;
   8         __u8 *buff = NULL, *newval = NULL;
   9         struct bpf_object *obj;
  10         struct bpf_map *map;
  11         __u32 duration = 0;
  12         size_t sz;
  13
  14         obj = bpf_object__open_file(file, NULL);
  15         err = libbpf_get_error(obj);
  16         if (CHECK_FAIL(err))
  17                 return;
  18
  19         map = bpf_object__find_map_by_name(obj, "test_glo.rodata");
  20         if (CHECK_FAIL(!map || !bpf_map__is_internal(map)))
  21                 goto out;
  22
  23         sz = bpf_map__def(map)->value_size;
  24         newval = malloc(sz);
  25         if (CHECK_FAIL(!newval))
  26                 goto out;
  27
  28         memset(newval, 0, sz);
  29         /* wrong size, should fail */
  30         err = bpf_map__set_initial_value(map, newval, sz - 1);
  31         if (CHECK(!err, "reject set initial value wrong size", "err %d\n", err))
  32                 goto out;
  33
  34         err = bpf_map__set_initial_value(map, newval, sz);
  35         if (CHECK(err, "set initial value", "err %d\n", err))
  36                 goto out;
  37
  38         err = bpf_object__load(obj);
  39         if (CHECK_FAIL(err))
  40                 goto out;
  41
  42         map_fd = bpf_map__fd(map);
  43         if (CHECK_FAIL(map_fd < 0))
  44                 goto out;
  45
  46         buff = malloc(sz);
  47         if (buff)
  48                 err = bpf_map_lookup_elem(map_fd, &zero, buff);
  49         if (CHECK(!buff || err || memcmp(buff, newval, sz),
  50                   "compare .rodata map data override",
  51                   "err %d errno %d\n", err, errno))
  52                 goto out;
  53
  54         memset(newval, 1, sz);
  55         /* object loaded - should fail */
  56         err = bpf_map__set_initial_value(map, newval, sz);
  57         CHECK(!err, "reject set initial value after load", "err %d\n", err);
  58 out:
  59         free(buff);
  60         free(newval);
  61         bpf_object__close(obj);
  62 }