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

   1// SPDX-License-Identifier: GPL-2.0
   2#include <test_progs.h>
   3#include "test_attach_probe.skel.h"
   4
   5/* this is how USDT semaphore is actually defined, except volatile modifier */
   6volatile unsigned short uprobe_ref_ctr __attribute__((unused)) __attribute((section(".probes")));
   7
   8void test_attach_probe(void)
   9{
  10        DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts);
  11        int duration = 0;
  12        struct bpf_link *kprobe_link, *kretprobe_link;
  13        struct bpf_link *uprobe_link, *uretprobe_link;
  14        struct test_attach_probe* skel;
  15        size_t uprobe_offset;
  16        ssize_t base_addr, ref_ctr_offset;
  17
  18        base_addr = get_base_addr();
  19        if (CHECK(base_addr < 0, "get_base_addr",
  20                  "failed to find base addr: %zd", base_addr))
  21                return;
  22        uprobe_offset = get_uprobe_offset(&get_base_addr, base_addr);
  23
  24        ref_ctr_offset = get_rel_offset((uintptr_t)&uprobe_ref_ctr);
  25        if (!ASSERT_GE(ref_ctr_offset, 0, "ref_ctr_offset"))
  26                return;
  27
  28        skel = test_attach_probe__open_and_load();
  29        if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
  30                return;
  31        if (CHECK(!skel->bss, "check_bss", ".bss wasn't mmap()-ed\n"))
  32                goto cleanup;
  33
  34        kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe,
  35                                                 false /* retprobe */,
  36                                                 SYS_NANOSLEEP_KPROBE_NAME);
  37        if (!ASSERT_OK_PTR(kprobe_link, "attach_kprobe"))
  38                goto cleanup;
  39        skel->links.handle_kprobe = kprobe_link;
  40
  41        kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe,
  42                                                    true /* retprobe */,
  43                                                    SYS_NANOSLEEP_KPROBE_NAME);
  44        if (!ASSERT_OK_PTR(kretprobe_link, "attach_kretprobe"))
  45                goto cleanup;
  46        skel->links.handle_kretprobe = kretprobe_link;
  47
  48        ASSERT_EQ(uprobe_ref_ctr, 0, "uprobe_ref_ctr_before");
  49
  50        uprobe_opts.retprobe = false;
  51        uprobe_opts.ref_ctr_offset = ref_ctr_offset;
  52        uprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe,
  53                                                      0 /* self pid */,
  54                                                      "/proc/self/exe",
  55                                                      uprobe_offset,
  56                                                      &uprobe_opts);
  57        if (!ASSERT_OK_PTR(uprobe_link, "attach_uprobe"))
  58                goto cleanup;
  59        skel->links.handle_uprobe = uprobe_link;
  60
  61        ASSERT_GT(uprobe_ref_ctr, 0, "uprobe_ref_ctr_after");
  62
  63        /* if uprobe uses ref_ctr, uretprobe has to use ref_ctr as well */
  64        uprobe_opts.retprobe = true;
  65        uprobe_opts.ref_ctr_offset = ref_ctr_offset;
  66        uretprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe,
  67                                                         -1 /* any pid */,
  68                                                         "/proc/self/exe",
  69                                                         uprobe_offset, &uprobe_opts);
  70        if (!ASSERT_OK_PTR(uretprobe_link, "attach_uretprobe"))
  71                goto cleanup;
  72        skel->links.handle_uretprobe = uretprobe_link;
  73
  74        /* trigger & validate kprobe && kretprobe */
  75        usleep(1);
  76
  77        if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res",
  78                  "wrong kprobe res: %d\n", skel->bss->kprobe_res))
  79                goto cleanup;
  80        if (CHECK(skel->bss->kretprobe_res != 2, "check_kretprobe_res",
  81                  "wrong kretprobe res: %d\n", skel->bss->kretprobe_res))
  82                goto cleanup;
  83
  84        /* trigger & validate uprobe & uretprobe */
  85        get_base_addr();
  86
  87        if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res",
  88                  "wrong uprobe res: %d\n", skel->bss->uprobe_res))
  89                goto cleanup;
  90        if (CHECK(skel->bss->uretprobe_res != 4, "check_uretprobe_res",
  91                  "wrong uretprobe res: %d\n", skel->bss->uretprobe_res))
  92                goto cleanup;
  93
  94cleanup:
  95        test_attach_probe__destroy(skel);
  96        ASSERT_EQ(uprobe_ref_ctr, 0, "uprobe_ref_ctr_cleanup");
  97}
  98