xref: /linux/tools/testing/selftests/bpf/prog_tests/attach_probe.c (revision eb9928bed003dd61a443d0ba51ae066429fbe735)
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;
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 %*s\n", &start, buf) == 2) {
15 		if (strcmp(buf, "r-xp") == 0) {
16 			fclose(f);
17 			return start;
18 		}
19 	}
20 
21 	fclose(f);
22 	return -EINVAL;
23 }
24 
25 void test_attach_probe(void)
26 {
27 	int duration = 0;
28 	struct bpf_link *kprobe_link, *kretprobe_link;
29 	struct bpf_link *uprobe_link, *uretprobe_link;
30 	struct test_attach_probe* skel;
31 	size_t uprobe_offset;
32 	ssize_t base_addr;
33 
34 	base_addr = get_base_addr();
35 	if (CHECK(base_addr < 0, "get_base_addr",
36 		  "failed to find base addr: %zd", base_addr))
37 		return;
38 	uprobe_offset = (size_t)&get_base_addr - base_addr;
39 
40 	skel = test_attach_probe__open_and_load();
41 	if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
42 		return;
43 	if (CHECK(!skel->bss, "check_bss", ".bss wasn't mmap()-ed\n"))
44 		goto cleanup;
45 
46 	kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe,
47 						 false /* retprobe */,
48 						 SYS_NANOSLEEP_KPROBE_NAME);
49 	if (CHECK(IS_ERR(kprobe_link), "attach_kprobe",
50 		  "err %ld\n", PTR_ERR(kprobe_link)))
51 		goto cleanup;
52 	skel->links.handle_kprobe = kprobe_link;
53 
54 	kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe,
55 						    true /* retprobe */,
56 						    SYS_NANOSLEEP_KPROBE_NAME);
57 	if (CHECK(IS_ERR(kretprobe_link), "attach_kretprobe",
58 		  "err %ld\n", PTR_ERR(kretprobe_link)))
59 		goto cleanup;
60 	skel->links.handle_kretprobe = kretprobe_link;
61 
62 	uprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uprobe,
63 						 false /* retprobe */,
64 						 0 /* self pid */,
65 						 "/proc/self/exe",
66 						 uprobe_offset);
67 	if (CHECK(IS_ERR(uprobe_link), "attach_uprobe",
68 		  "err %ld\n", PTR_ERR(uprobe_link)))
69 		goto cleanup;
70 	skel->links.handle_uprobe = uprobe_link;
71 
72 	uretprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uretprobe,
73 						    true /* retprobe */,
74 						    -1 /* any pid */,
75 						    "/proc/self/exe",
76 						    uprobe_offset);
77 	if (CHECK(IS_ERR(uretprobe_link), "attach_uretprobe",
78 		  "err %ld\n", PTR_ERR(uretprobe_link)))
79 		goto cleanup;
80 	skel->links.handle_uretprobe = uretprobe_link;
81 
82 	/* trigger & validate kprobe && kretprobe */
83 	usleep(1);
84 
85 	if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res",
86 		  "wrong kprobe res: %d\n", skel->bss->kprobe_res))
87 		goto cleanup;
88 	if (CHECK(skel->bss->kretprobe_res != 2, "check_kretprobe_res",
89 		  "wrong kretprobe res: %d\n", skel->bss->kretprobe_res))
90 		goto cleanup;
91 
92 	/* trigger & validate uprobe & uretprobe */
93 	get_base_addr();
94 
95 	if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res",
96 		  "wrong uprobe res: %d\n", skel->bss->uprobe_res))
97 		goto cleanup;
98 	if (CHECK(skel->bss->uretprobe_res != 4, "check_uretprobe_res",
99 		  "wrong uretprobe res: %d\n", skel->bss->uretprobe_res))
100 		goto cleanup;
101 
102 cleanup:
103 	test_attach_probe__destroy(skel);
104 }
105