1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2021 Facebook */
3 #include <test_progs.h>
4 #include <sys/types.h>
5 #include <unistd.h>
6 #include "find_vma.skel.h"
7 #include "find_vma_fail1.skel.h"
8 #include "find_vma_fail2.skel.h"
9 
10 static void test_and_reset_skel(struct find_vma *skel, int expected_find_zero_ret)
11 {
12 	ASSERT_EQ(skel->bss->found_vm_exec, 1, "found_vm_exec");
13 	ASSERT_EQ(skel->data->find_addr_ret, 0, "find_addr_ret");
14 	ASSERT_EQ(skel->data->find_zero_ret, expected_find_zero_ret, "find_zero_ret");
15 	ASSERT_OK_PTR(strstr(skel->bss->d_iname, "test_progs"), "find_test_progs");
16 
17 	skel->bss->found_vm_exec = 0;
18 	skel->data->find_addr_ret = -1;
19 	skel->data->find_zero_ret = -1;
20 	skel->bss->d_iname[0] = 0;
21 }
22 
23 static int open_pe(void)
24 {
25 	struct perf_event_attr attr = {0};
26 	int pfd;
27 
28 	/* create perf event */
29 	attr.size = sizeof(attr);
30 	attr.type = PERF_TYPE_HARDWARE;
31 	attr.config = PERF_COUNT_HW_CPU_CYCLES;
32 	attr.freq = 1;
33 	attr.sample_freq = 4000;
34 	pfd = syscall(__NR_perf_event_open, &attr, 0, -1, -1, PERF_FLAG_FD_CLOEXEC);
35 
36 	return pfd >= 0 ? pfd : -errno;
37 }
38 
39 static void test_find_vma_pe(struct find_vma *skel)
40 {
41 	struct bpf_link *link = NULL;
42 	volatile int j = 0;
43 	int pfd, i;
44 
45 	pfd = open_pe();
46 	if (pfd < 0) {
47 		if (pfd == -ENOENT || pfd == -EOPNOTSUPP) {
48 			printf("%s:SKIP:no PERF_COUNT_HW_CPU_CYCLES\n", __func__);
49 			test__skip();
50 			goto cleanup;
51 		}
52 		if (!ASSERT_GE(pfd, 0, "perf_event_open"))
53 			goto cleanup;
54 	}
55 
56 	link = bpf_program__attach_perf_event(skel->progs.handle_pe, pfd);
57 	if (!ASSERT_OK_PTR(link, "attach_perf_event"))
58 		goto cleanup;
59 
60 	for (i = 0; i < 1000000; ++i)
61 		++j;
62 
63 	test_and_reset_skel(skel, -EBUSY /* in nmi, irq_work is busy */);
64 cleanup:
65 	bpf_link__destroy(link);
66 	close(pfd);
67 }
68 
69 static void test_find_vma_kprobe(struct find_vma *skel)
70 {
71 	int err;
72 
73 	err = find_vma__attach(skel);
74 	if (!ASSERT_OK(err, "get_branch_snapshot__attach"))
75 		return;
76 
77 	getpgid(skel->bss->target_pid);
78 	test_and_reset_skel(skel, -ENOENT /* could not find vma for ptr 0 */);
79 }
80 
81 static void test_illegal_write_vma(void)
82 {
83 	struct find_vma_fail1 *skel;
84 
85 	skel = find_vma_fail1__open_and_load();
86 	if (!ASSERT_ERR_PTR(skel, "find_vma_fail1__open_and_load"))
87 		find_vma_fail1__destroy(skel);
88 }
89 
90 static void test_illegal_write_task(void)
91 {
92 	struct find_vma_fail2 *skel;
93 
94 	skel = find_vma_fail2__open_and_load();
95 	if (!ASSERT_ERR_PTR(skel, "find_vma_fail2__open_and_load"))
96 		find_vma_fail2__destroy(skel);
97 }
98 
99 void serial_test_find_vma(void)
100 {
101 	struct find_vma *skel;
102 
103 	skel = find_vma__open_and_load();
104 	if (!ASSERT_OK_PTR(skel, "find_vma__open_and_load"))
105 		return;
106 
107 	skel->bss->target_pid = getpid();
108 	skel->bss->addr = (__u64)(uintptr_t)test_find_vma_pe;
109 
110 	test_find_vma_pe(skel);
111 	usleep(100000); /* allow the irq_work to finish */
112 	test_find_vma_kprobe(skel);
113 
114 	find_vma__destroy(skel);
115 	test_illegal_write_vma();
116 	test_illegal_write_task();
117 }
118