xref: /linux/tools/testing/selftests/bpf/prog_tests/attach_probe.c (revision d9c00c3b1639a3c8f46663cc042a3768d222021f)
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 BPF_EMBED_OBJ(probe, "test_attach_probe.o");
26 
27 void test_attach_probe(void)
28 {
29 	int duration = 0;
30 	struct bpf_link *kprobe_link, *kretprobe_link;
31 	struct bpf_link *uprobe_link, *uretprobe_link;
32 	struct test_attach_probe* skel;
33 	size_t uprobe_offset;
34 	ssize_t base_addr;
35 
36 	base_addr = get_base_addr();
37 	if (CHECK(base_addr < 0, "get_base_addr",
38 		  "failed to find base addr: %zd", base_addr))
39 		return;
40 	uprobe_offset = (size_t)&get_base_addr - base_addr;
41 
42 	skel = test_attach_probe__open_and_load(&probe_embed);
43 	if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
44 		return;
45 	if (CHECK(!skel->bss, "check_bss", ".bss wasn't mmap()-ed\n"))
46 		goto cleanup;
47 
48 	kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe,
49 						 false /* retprobe */,
50 						 SYS_NANOSLEEP_KPROBE_NAME);
51 	if (CHECK(IS_ERR(kprobe_link), "attach_kprobe",
52 		  "err %ld\n", PTR_ERR(kprobe_link)))
53 		goto cleanup;
54 	skel->links.handle_kprobe = kprobe_link;
55 
56 	kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe,
57 						    true /* retprobe */,
58 						    SYS_NANOSLEEP_KPROBE_NAME);
59 	if (CHECK(IS_ERR(kretprobe_link), "attach_kretprobe",
60 		  "err %ld\n", PTR_ERR(kretprobe_link)))
61 		goto cleanup;
62 	skel->links.handle_kretprobe = kretprobe_link;
63 
64 	uprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uprobe,
65 						 false /* retprobe */,
66 						 0 /* self pid */,
67 						 "/proc/self/exe",
68 						 uprobe_offset);
69 	if (CHECK(IS_ERR(uprobe_link), "attach_uprobe",
70 		  "err %ld\n", PTR_ERR(uprobe_link)))
71 		goto cleanup;
72 	skel->links.handle_uprobe = uprobe_link;
73 
74 	uretprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uretprobe,
75 						    true /* retprobe */,
76 						    -1 /* any pid */,
77 						    "/proc/self/exe",
78 						    uprobe_offset);
79 	if (CHECK(IS_ERR(uretprobe_link), "attach_uretprobe",
80 		  "err %ld\n", PTR_ERR(uretprobe_link)))
81 		goto cleanup;
82 	skel->links.handle_uretprobe = uretprobe_link;
83 
84 	/* trigger & validate kprobe && kretprobe */
85 	usleep(1);
86 
87 	if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res",
88 		  "wrong kprobe res: %d\n", skel->bss->kprobe_res))
89 		goto cleanup;
90 	if (CHECK(skel->bss->kretprobe_res != 2, "check_kretprobe_res",
91 		  "wrong kretprobe res: %d\n", skel->bss->kretprobe_res))
92 		goto cleanup;
93 
94 	/* trigger & validate uprobe & uretprobe */
95 	get_base_addr();
96 
97 	if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res",
98 		  "wrong uprobe res: %d\n", skel->bss->uprobe_res))
99 		goto cleanup;
100 	if (CHECK(skel->bss->uretprobe_res != 4, "check_uretprobe_res",
101 		  "wrong uretprobe res: %d\n", skel->bss->uretprobe_res))
102 		goto cleanup;
103 
104 cleanup:
105 	test_attach_probe__destroy(skel);
106 }
107