1// SPDX-License-Identifier: GPL-2.0
2#define _GNU_SOURCE
3#include <pthread.h>
4#include <sched.h>
5#include <sys/socket.h>
6#include <test_progs.h>
7
8#define MAX_CNT_RAWTP	10ull
9#define MAX_STACK_RAWTP	100
10
11static int duration = 0;
12
13struct get_stack_trace_t {
14	int pid;
15	int kern_stack_size;
16	int user_stack_size;
17	int user_stack_buildid_size;
18	__u64 kern_stack[MAX_STACK_RAWTP];
19	__u64 user_stack[MAX_STACK_RAWTP];
20	struct bpf_stack_build_id user_stack_buildid[MAX_STACK_RAWTP];
21};
22
23static void get_stack_print_output(void *ctx, int cpu, void *data, __u32 size)
24{
25	bool good_kern_stack = false, good_user_stack = false;
26	const char *nonjit_func = "___bpf_prog_run";
27	/* perfbuf-submitted data is 4-byte aligned, but we need 8-byte
28	 * alignment, so copy data into a local variable, for simplicity
29	 */
30	struct get_stack_trace_t e;
31	int i, num_stack;
32	struct ksym *ks;
33
34	memset(&e, 0, sizeof(e));
35	memcpy(&e, data, size <= sizeof(e) ? size : sizeof(e));
36
37	if (size < sizeof(struct get_stack_trace_t)) {
38		__u64 *raw_data = data;
39		bool found = false;
40
41		num_stack = size / sizeof(__u64);
42		/* If jit is enabled, we do not have a good way to
43		 * verify the sanity of the kernel stack. So we
44		 * just assume it is good if the stack is not empty.
45		 * This could be improved in the future.
46		 */
47		if (env.jit_enabled) {
48			found = num_stack > 0;
49		} else {
50			for (i = 0; i < num_stack; i++) {
51				ks = ksym_search(raw_data[i]);
52				if (ks && (strcmp(ks->name, nonjit_func) == 0)) {
53					found = true;
54					break;
55				}
56			}
57		}
58		if (found) {
59			good_kern_stack = true;
60			good_user_stack = true;
61		}
62	} else {
63		num_stack = e.kern_stack_size / sizeof(__u64);
64		if (env.jit_enabled) {
65			good_kern_stack = num_stack > 0;
66		} else {
67			for (i = 0; i < num_stack; i++) {
68				ks = ksym_search(e.kern_stack[i]);
69				if (ks && (strcmp(ks->name, nonjit_func) == 0)) {
70					good_kern_stack = true;
71					break;
72				}
73			}
74		}
75		if (e.user_stack_size > 0 && e.user_stack_buildid_size > 0)
76			good_user_stack = true;
77	}
78
79	if (!good_kern_stack)
80	    CHECK(!good_kern_stack, "kern_stack", "corrupted kernel stack\n");
81	if (!good_user_stack)
82	    CHECK(!good_user_stack, "user_stack", "corrupted user stack\n");
83}
84
85void test_get_stack_raw_tp(void)
86{
87	const char *file = "./test_get_stack_rawtp.bpf.o";
88	const char *file_err = "./test_get_stack_rawtp_err.bpf.o";
89	const char *prog_name = "bpf_prog1";
90	int i, err, prog_fd, exp_cnt = MAX_CNT_RAWTP;
91	struct perf_buffer *pb = NULL;
92	struct bpf_link *link = NULL;
93	struct timespec tv = {0, 10};
94	struct bpf_program *prog;
95	struct bpf_object *obj;
96	struct bpf_map *map;
97	cpu_set_t cpu_set;
98
99	err = bpf_prog_test_load(file_err, BPF_PROG_TYPE_RAW_TRACEPOINT, &obj, &prog_fd);
100	if (CHECK(err >= 0, "prog_load raw tp", "err %d errno %d\n", err, errno))
101		return;
102
103	err = bpf_prog_test_load(file, BPF_PROG_TYPE_RAW_TRACEPOINT, &obj, &prog_fd);
104	if (CHECK(err, "prog_load raw tp", "err %d errno %d\n", err, errno))
105		return;
106
107	prog = bpf_object__find_program_by_name(obj, prog_name);
108	if (CHECK(!prog, "find_probe", "prog '%s' not found\n", prog_name))
109		goto close_prog;
110
111	map = bpf_object__find_map_by_name(obj, "perfmap");
112	if (CHECK(!map, "bpf_find_map", "not found\n"))
113		goto close_prog;
114
115	err = load_kallsyms();
116	if (CHECK(err < 0, "load_kallsyms", "err %d errno %d\n", err, errno))
117		goto close_prog;
118
119	CPU_ZERO(&cpu_set);
120	CPU_SET(0, &cpu_set);
121	err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set), &cpu_set);
122	if (CHECK(err, "set_affinity", "err %d, errno %d\n", err, errno))
123		goto close_prog;
124
125	link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");
126	if (!ASSERT_OK_PTR(link, "attach_raw_tp"))
127		goto close_prog;
128
129	pb = perf_buffer__new(bpf_map__fd(map), 8, get_stack_print_output,
130			      NULL, NULL, NULL);
131	if (!ASSERT_OK_PTR(pb, "perf_buf__new"))
132		goto close_prog;
133
134	/* trigger some syscall action */
135	for (i = 0; i < MAX_CNT_RAWTP; i++)
136		nanosleep(&tv, NULL);
137
138	while (exp_cnt > 0) {
139		err = perf_buffer__poll(pb, 100);
140		if (err < 0 && CHECK(err < 0, "pb__poll", "err %d\n", err))
141			goto close_prog;
142		exp_cnt -= err;
143	}
144
145close_prog:
146	bpf_link__destroy(link);
147	perf_buffer__free(pb);
148	bpf_object__close(obj);
149}
150