LXR linux/tools/testing/selftests/bpf/prog_tests/module

   1// SPDX-License-Identifier: GPL-2.0
   2/* Copyright (c) 2020 Facebook */
   3
   4#include <test_progs.h>
   5#include "test_module_attach.skel.h"
   6
   7static int duration;
   8
   9static int trigger_module_test_read(int read_sz)
  10{
  11        int fd, err;
  12
  13        fd = open("/sys/kernel/bpf_testmod", O_RDONLY);
  14        err = -errno;
  15        if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err))
  16                return err;
  17
  18        read(fd, NULL, read_sz);
  19        close(fd);
  20
  21        return 0;
  22}
  23
  24static int trigger_module_test_write(int write_sz)
  25{
  26        int fd, err;
  27        char *buf = malloc(write_sz);
  28
  29        if (!buf)
  30                return -ENOMEM;
  31
  32        memset(buf, 'a', write_sz);
  33        buf[write_sz-1] = '\0';
  34
  35        fd = open("/sys/kernel/bpf_testmod", O_WRONLY);
  36        err = -errno;
  37        if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) {
  38                free(buf);
  39                return err;
  40        }
  41
  42        write(fd, buf, write_sz);
  43        close(fd);
  44        free(buf);
  45        return 0;
  46}
  47
  48static int delete_module(const char *name, int flags)
  49{
  50        return syscall(__NR_delete_module, name, flags);
  51}
  52
  53void test_module_attach(void)
  54{
  55        const int READ_SZ = 456;
  56        const int WRITE_SZ = 457;
  57        struct test_module_attach* skel;
  58        struct test_module_attach__bss *bss;
  59        struct bpf_link *link;
  60        int err;
  61
  62        skel = test_module_attach__open();
  63        if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
  64                return;
  65
  66        err = bpf_program__set_attach_target(skel->progs.handle_fentry_manual,
  67                                             0, "bpf_testmod_test_read");
  68        ASSERT_OK(err, "set_attach_target");
  69
  70        err = test_module_attach__load(skel);
  71        if (CHECK(err, "skel_load", "failed to load skeleton\n"))
  72                return;
  73
  74        bss = skel->bss;
  75
  76        err = test_module_attach__attach(skel);
  77        if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
  78                goto cleanup;
  79
  80        /* trigger tracepoint */
  81        ASSERT_OK(trigger_module_test_read(READ_SZ), "trigger_read");
  82        ASSERT_OK(trigger_module_test_write(WRITE_SZ), "trigger_write");
  83
  84        ASSERT_EQ(bss->raw_tp_read_sz, READ_SZ, "raw_tp");
  85        ASSERT_EQ(bss->raw_tp_bare_write_sz, WRITE_SZ, "raw_tp_bare");
  86        ASSERT_EQ(bss->tp_btf_read_sz, READ_SZ, "tp_btf");
  87        ASSERT_EQ(bss->fentry_read_sz, READ_SZ, "fentry");
  88        ASSERT_EQ(bss->fentry_manual_read_sz, READ_SZ, "fentry_manual");
  89        ASSERT_EQ(bss->fexit_read_sz, READ_SZ, "fexit");
  90        ASSERT_EQ(bss->fexit_ret, -EIO, "fexit_tet");
  91        ASSERT_EQ(bss->fmod_ret_read_sz, READ_SZ, "fmod_ret");
  92
  93        test_module_attach__detach(skel);
  94
  95        /* attach fentry/fexit and make sure it get's module reference */
  96        link = bpf_program__attach(skel->progs.handle_fentry);
  97        if (!ASSERT_OK_PTR(link, "attach_fentry"))
  98                goto cleanup;
  99
 100        ASSERT_ERR(delete_module("bpf_testmod", 0), "delete_module");
 101        bpf_link__destroy(link);
 102
 103        link = bpf_program__attach(skel->progs.handle_fexit);
 104        if (!ASSERT_OK_PTR(link, "attach_fexit"))
 105                goto cleanup;
 106
 107        ASSERT_ERR(delete_module("bpf_testmod", 0), "delete_module");
 108        bpf_link__destroy(link);
 109
 110cleanup:
 111        test_module_attach__destroy(skel);
 112}
 113