1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2017 Facebook
3 */
4 #include <stdio.h>
5 #include <unistd.h>
6 #include <fcntl.h>
7 #include <stdlib.h>
8 #include <signal.h>
9 #include <linux/bpf.h>
10 #include <string.h>
11 #include <linux/perf_event.h>
12 #include <errno.h>
13 #include <assert.h>
14 #include <stdbool.h>
15 #include <sys/resource.h>
16 #include <bpf/bpf.h>
17 #include "bpf_load.h"
18
19 /* This program verifies bpf attachment to tracepoint sys_enter_* and sys_exit_*.
20 * This requires kernel CONFIG_FTRACE_SYSCALLS to be set.
21 */
22
usage(const char * cmd)23 static void usage(const char *cmd)
24 {
25 printf("USAGE: %s [-i num_progs] [-h]\n", cmd);
26 printf(" -i num_progs # number of progs of the test\n");
27 printf(" -h # help\n");
28 }
29
verify_map(int map_id)30 static void verify_map(int map_id)
31 {
32 __u32 key = 0;
33 __u32 val;
34
35 if (bpf_map_lookup_elem(map_id, &key, &val) != 0) {
36 fprintf(stderr, "map_lookup failed: %s\n", strerror(errno));
37 return;
38 }
39 if (val == 0) {
40 fprintf(stderr, "failed: map #%d returns value 0\n", map_id);
41 return;
42 }
43 val = 0;
44 if (bpf_map_update_elem(map_id, &key, &val, BPF_ANY) != 0) {
45 fprintf(stderr, "map_update failed: %s\n", strerror(errno));
46 return;
47 }
48 }
49
test(char * filename,int num_progs)50 static int test(char *filename, int num_progs)
51 {
52 int i, fd, map0_fds[num_progs], map1_fds[num_progs];
53
54 for (i = 0; i < num_progs; i++) {
55 if (load_bpf_file(filename)) {
56 fprintf(stderr, "%s", bpf_log_buf);
57 return 1;
58 }
59 printf("prog #%d: map ids %d %d\n", i, map_fd[0], map_fd[1]);
60 map0_fds[i] = map_fd[0];
61 map1_fds[i] = map_fd[1];
62 }
63
64 /* current load_bpf_file has perf_event_open default pid = -1
65 * and cpu = 0, which permits attached bpf execution on
66 * all cpus for all pid's. bpf program execution ignores
67 * cpu affinity.
68 */
69 /* trigger some "open" operations */
70 fd = open(filename, O_RDONLY);
71 if (fd < 0) {
72 fprintf(stderr, "open failed: %s\n", strerror(errno));
73 return 1;
74 }
75 close(fd);
76
77 /* verify the map */
78 for (i = 0; i < num_progs; i++) {
79 verify_map(map0_fds[i]);
80 verify_map(map1_fds[i]);
81 }
82
83 return 0;
84 }
85
main(int argc,char ** argv)86 int main(int argc, char **argv)
87 {
88 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
89 int opt, num_progs = 1;
90 char filename[256];
91
92 while ((opt = getopt(argc, argv, "i:h")) != -1) {
93 switch (opt) {
94 case 'i':
95 num_progs = atoi(optarg);
96 break;
97 case 'h':
98 default:
99 usage(argv[0]);
100 return 0;
101 }
102 }
103
104 setrlimit(RLIMIT_MEMLOCK, &r);
105 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
106
107 return test(filename, num_progs);
108 }
109
