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

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <test_progs.h>
   3 #include "test_attach_probe.skel.h"
   4
   5 ssize_t get_base_addr() {
   6         size_t start, offset;
   7         char buf[256];
   8         FILE *f;
   9
  10         f = fopen("/proc/self/maps", "r");
  11         if (!f)
  12                 return -errno;
  13
  14         while (fscanf(f, "%zx-%*x %s %zx %*[^\n]\n",
  15                       &start, buf, &offset) == 3) {
  16                 if (strcmp(buf, "r-xp") == 0) {
  17                         fclose(f);
  18                         return start - offset;
  19                 }
  20         }
  21
  22         fclose(f);
  23         return -EINVAL;
  24 }
  25
  26 void test_attach_probe(void)
  27 {
  28         int duration = 0;
  29         struct bpf_link *kprobe_link, *kretprobe_link;
  30         struct bpf_link *uprobe_link, *uretprobe_link;
  31         struct test_attach_probe* skel;
  32         size_t uprobe_offset;
  33         ssize_t base_addr;
  34
  35         base_addr = get_base_addr();
  36         if (CHECK(base_addr < 0, "get_base_addr",
  37                   "failed to find base addr: %zd", base_addr))
  38                 return;
  39         uprobe_offset = (size_t)&get_base_addr - base_addr;
  40
  41         skel = test_attach_probe__open_and_load();
  42         if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
  43                 return;
  44         if (CHECK(!skel->bss, "check_bss", ".bss wasn't mmap()-ed\n"))
  45                 goto cleanup;
  46
  47         kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe,
  48                                                  false /* retprobe */,
  49                                                  SYS_NANOSLEEP_KPROBE_NAME);
  50         if (CHECK(IS_ERR(kprobe_link), "attach_kprobe",
  51                   "err %ld\n", PTR_ERR(kprobe_link)))
  52                 goto cleanup;
  53         skel->links.handle_kprobe = kprobe_link;
  54
  55         kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe,
  56                                                     true /* retprobe */,
  57                                                     SYS_NANOSLEEP_KPROBE_NAME);
  58         if (CHECK(IS_ERR(kretprobe_link), "attach_kretprobe",
  59                   "err %ld\n", PTR_ERR(kretprobe_link)))
  60                 goto cleanup;
  61         skel->links.handle_kretprobe = kretprobe_link;
  62
  63         uprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uprobe,
  64                                                  false /* retprobe */,
  65                                                  0 /* self pid */,
  66                                                  "/proc/self/exe",
  67                                                  uprobe_offset);
  68         if (CHECK(IS_ERR(uprobe_link), "attach_uprobe",
  69                   "err %ld\n", PTR_ERR(uprobe_link)))
  70                 goto cleanup;
  71         skel->links.handle_uprobe = uprobe_link;
  72
  73         uretprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uretprobe,
  74                                                     true /* retprobe */,
  75                                                     -1 /* any pid */,
  76                                                     "/proc/self/exe",
  77                                                     uprobe_offset);
  78         if (CHECK(IS_ERR(uretprobe_link), "attach_uretprobe",
  79                   "err %ld\n", PTR_ERR(uretprobe_link)))
  80                 goto cleanup;
  81         skel->links.handle_uretprobe = uretprobe_link;
  82
  83         /* trigger & validate kprobe && kretprobe */
  84         usleep(1);
  85
  86         if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res",
  87                   "wrong kprobe res: %d\n", skel->bss->kprobe_res))
  88                 goto cleanup;
  89         if (CHECK(skel->bss->kretprobe_res != 2, "check_kretprobe_res",
  90                   "wrong kretprobe res: %d\n", skel->bss->kretprobe_res))
  91                 goto cleanup;
  92
  93         /* trigger & validate uprobe & uretprobe */
  94         get_base_addr();
  95
  96         if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res",
  97                   "wrong uprobe res: %d\n", skel->bss->uprobe_res))
  98                 goto cleanup;
  99         if (CHECK(skel->bss->uretprobe_res != 4, "check_uretprobe_res",
 100                   "wrong uretprobe res: %d\n", skel->bss->uretprobe_res))
 101                 goto cleanup;
 102
 103 cleanup:
 104         test_attach_probe__destroy(skel);
 105 }