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

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #define _GNU_SOURCE
   3 #include <test_progs.h>
   4
   5 struct inst {
   6         struct bpf_object *obj;
   7         struct bpf_link   *link;
   8 };
   9
  10 static struct bpf_program *load_prog(char *file, char *name, struct inst *inst)
  11 {
  12         struct bpf_object *obj;
  13         struct bpf_program *prog;
  14         int err;
  15
  16         obj = bpf_object__open_file(file, NULL);
  17         if (!ASSERT_OK_PTR(obj, "obj_open_file"))
  18                 return NULL;
  19
  20         inst->obj = obj;
  21
  22         err = bpf_object__load(obj);
  23         if (!ASSERT_OK(err, "obj_load"))
  24                 return NULL;
  25
  26         prog = bpf_object__find_program_by_name(obj, name);
  27         if (!ASSERT_OK_PTR(prog, "obj_find_prog"))
  28                 return NULL;
  29
  30         return prog;
  31 }
  32
  33 /* TODO: use different target function to run in concurrent mode */
  34 void serial_test_trampoline_count(void)
  35 {
  36         char *file = "test_trampoline_count.bpf.o";
  37         char *const progs[] = { "fentry_test", "fmod_ret_test", "fexit_test" };
  38         int bpf_max_tramp_links, err, i, prog_fd;
  39         struct bpf_program *prog;
  40         struct bpf_link *link;
  41         struct inst *inst;
  42         LIBBPF_OPTS(bpf_test_run_opts, opts);
  43
  44         bpf_max_tramp_links = get_bpf_max_tramp_links();
  45         if (!ASSERT_GE(bpf_max_tramp_links, 1, "bpf_max_tramp_links"))
  46                 return;
  47         inst = calloc(bpf_max_tramp_links + 1, sizeof(*inst));
  48         if (!ASSERT_OK_PTR(inst, "inst"))
  49                 return;
  50
  51         /* attach 'allowed' trampoline programs */
  52         for (i = 0; i < bpf_max_tramp_links; i++) {
  53                 prog = load_prog(file, progs[i % ARRAY_SIZE(progs)], &inst[i]);
  54                 if (!prog)
  55                         goto cleanup;
  56
  57                 link = bpf_program__attach(prog);
  58                 if (!ASSERT_OK_PTR(link, "attach_prog"))
  59                         goto cleanup;
  60
  61                 inst[i].link = link;
  62         }
  63
  64         /* and try 1 extra.. */
  65         prog = load_prog(file, "fmod_ret_test", &inst[i]);
  66         if (!prog)
  67                 goto cleanup;
  68
  69         /* ..that needs to fail */
  70         link = bpf_program__attach(prog);
  71         if (!ASSERT_ERR_PTR(link, "attach_prog")) {
  72                 inst[i].link = link;
  73                 goto cleanup;
  74         }
  75
  76         /* with E2BIG error */
  77         if (!ASSERT_EQ(libbpf_get_error(link), -E2BIG, "E2BIG"))
  78                 goto cleanup;
  79         if (!ASSERT_EQ(link, NULL, "ptr_is_null"))
  80                 goto cleanup;
  81
  82         /* and finally execute the probe */
  83         prog_fd = bpf_program__fd(prog);
  84         if (!ASSERT_GE(prog_fd, 0, "bpf_program__fd"))
  85                 goto cleanup;
  86
  87         err = bpf_prog_test_run_opts(prog_fd, &opts);
  88         if (!ASSERT_OK(err, "bpf_prog_test_run_opts"))
  89                 goto cleanup;
  90
  91         ASSERT_EQ(opts.retval & 0xffff, 33, "bpf_modify_return_test.result");
  92         ASSERT_EQ(opts.retval >> 16, 2, "bpf_modify_return_test.side_effect");
  93
  94 cleanup:
  95         for (; i >= 0; i--) {
  96                 bpf_link__destroy(inst[i].link);
  97                 bpf_object__close(inst[i].obj);
  98         }
  99         free(inst);
 100 }