1 /*
2 * Copyright (c) 2015-2017 Dmitry V. Levin <ldv@altlinux.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include "tests.h"
29 #include <asm/unistd.h>
30
31 #if defined HAVE_UNION_BPF_ATTR_LOG_BUF && defined __NR_bpf
32 # include <stdio.h>
33 # include <stdint.h>
34 # include <unistd.h>
35 # include <linux/bpf.h>
36
37 static const struct bpf_insn insns[] = {
38 { .code = BPF_JMP | BPF_EXIT }
39 };
40
41 static const char *errstr;
42 static char log_buf[4096];
43
44 static long
sys_bpf(kernel_ulong_t cmd,kernel_ulong_t attr,kernel_ulong_t size)45 sys_bpf(kernel_ulong_t cmd, kernel_ulong_t attr, kernel_ulong_t size)
46 {
47 long rc = syscall(__NR_bpf, cmd, attr, size);
48 errstr = sprintrc(rc);
49 return rc;
50 }
51
52 static int
map_create(void)53 map_create(void)
54 {
55 union bpf_attr attr = {
56 .key_size = 4,
57 .value_size = 8,
58 .max_entries = 256
59 };
60 void *const t_attr = tail_memdup(&attr, sizeof(attr));
61 return sys_bpf(BPF_MAP_CREATE, (unsigned long) t_attr, sizeof(attr));
62 }
63
64 static int
map_any(int cmd)65 map_any(int cmd)
66 {
67 union bpf_attr attr = {
68 .map_fd = -1,
69 .key = 0xdeadbeef,
70 .value = 0xbadc0ded
71 };
72 void *const t_attr = tail_memdup(&attr, sizeof(attr));
73 return sys_bpf(cmd, (unsigned long) t_attr, sizeof(attr));
74 }
75
76 static int
prog_load(void)77 prog_load(void)
78 {
79 union bpf_attr attr = {
80 .insn_cnt = sizeof(insns) / sizeof(insns[0]),
81 .insns = (unsigned long) insns,
82 .license = (unsigned long) "GPL",
83 .log_level = 42,
84 .log_size = sizeof(log_buf),
85 .log_buf = (unsigned long) log_buf
86 };
87 void *const t_attr = tail_memdup(&attr, sizeof(attr));
88 return sys_bpf(BPF_PROG_LOAD, (unsigned long) t_attr, sizeof(attr));
89 }
90
91 /*
92 * bpf() syscall and its first six commands were introduced in Linux kernel
93 * 3.18. Some additional commands were added afterwards, so we need to take
94 * precautions to make sure the tests compile.
95 *
96 * BPF_OBJ_PIN and BPF_OBJ_GET commands appear in kernel 4.4.
97 */
98 # ifdef HAVE_UNION_BPF_ATTR_BPF_FD
99 static int
obj_manage(int cmd)100 obj_manage(int cmd)
101 {
102 union bpf_attr attr = {
103 .pathname = (unsigned long) "/sys/fs/bpf/foo/bar",
104 .bpf_fd = -1
105 };
106 void *const t_attr = tail_memdup(&attr, sizeof(attr));
107 return sys_bpf(cmd, (unsigned long) t_attr, sizeof(attr));
108 }
109 # endif
110
111 /* BPF_PROG_ATTACH and BPF_PROG_DETACH commands appear in kernel 4.10. */
112 # ifdef HAVE_UNION_BPF_ATTR_ATTACH_TYPE
113 static int
prog_cgroup(int cmd)114 prog_cgroup(int cmd)
115 {
116 union bpf_attr attr = {
117 .target_fd = -1,
118 .attach_bpf_fd = -1,
119 .attach_type = 0
120 };
121 void *const t_attr = tail_memdup(&attr, sizeof(attr));
122 return sys_bpf(cmd, (unsigned long) t_attr, sizeof(attr));
123 }
124 # endif
125
126 static unsigned long efault;
127
128 static void
bogus_bpf(int cmd,const char * name)129 bogus_bpf(int cmd, const char *name)
130 {
131 const unsigned long bogus_size = 1024;
132 const unsigned long bogus_addr = efault - bogus_size;
133
134 sys_bpf(cmd, efault, 4);
135 printf("bpf(%s, %#lx, %lu) = %s\n",
136 name, efault, 4UL, errstr);
137
138 sys_bpf(cmd, efault, bogus_size);
139 printf("bpf(%s, %#lx, %lu) = %s\n",
140 name, efault, bogus_size, errstr);
141
142 sys_bpf(cmd, bogus_addr, 0);
143 printf("bpf(%s, %#lx, %lu) = %s\n",
144 name, bogus_addr, 0UL, errstr);
145 }
146
147 #define BOGUS_BPF(cmd) bogus_bpf(cmd, #cmd)
148
149 int
main(void)150 main(void)
151 {
152 efault = (unsigned long) tail_alloc(1) + 1;
153
154 map_create();
155 printf("bpf(BPF_MAP_CREATE"
156 ", {map_type=BPF_MAP_TYPE_UNSPEC, key_size=4"
157 ", value_size=8, max_entries=256}, %u) = %s\n",
158 (unsigned) sizeof(union bpf_attr), errstr);
159 BOGUS_BPF(BPF_MAP_CREATE);
160
161 map_any(BPF_MAP_LOOKUP_ELEM);
162 printf("bpf(BPF_MAP_LOOKUP_ELEM"
163 ", {map_fd=-1, key=0xdeadbeef}, %u) = %s\n",
164 (unsigned) sizeof(union bpf_attr), errstr);
165 BOGUS_BPF(BPF_MAP_LOOKUP_ELEM);
166
167 map_any(BPF_MAP_UPDATE_ELEM);
168 printf("bpf(BPF_MAP_UPDATE_ELEM"
169 ", {map_fd=-1, key=0xdeadbeef"
170 ", value=0xbadc0ded, flags=BPF_ANY}, %u) = %s\n",
171 (unsigned) sizeof(union bpf_attr), errstr);
172 BOGUS_BPF(BPF_MAP_UPDATE_ELEM);
173
174 map_any(BPF_MAP_DELETE_ELEM);
175 printf("bpf(BPF_MAP_DELETE_ELEM"
176 ", {map_fd=-1, key=0xdeadbeef}, %u) = %s\n",
177 (unsigned) sizeof(union bpf_attr), errstr);
178 BOGUS_BPF(BPF_MAP_DELETE_ELEM);
179
180 map_any(BPF_MAP_GET_NEXT_KEY);
181 printf("bpf(BPF_MAP_GET_NEXT_KEY"
182 ", {map_fd=-1, key=0xdeadbeef}, %u) = %s\n",
183 (unsigned) sizeof(union bpf_attr), errstr);
184 BOGUS_BPF(BPF_MAP_GET_NEXT_KEY);
185
186 prog_load();
187 printf("bpf(BPF_PROG_LOAD"
188 ", {prog_type=BPF_PROG_TYPE_UNSPEC, insn_cnt=1, insns=%p"
189 ", license=\"GPL\", log_level=42, log_size=4096, log_buf=%p"
190 ", kern_version=0}, %u) = %s\n",
191 insns, log_buf, (unsigned) sizeof(union bpf_attr), errstr);
192 BOGUS_BPF(BPF_PROG_LOAD);
193
194 # ifdef HAVE_UNION_BPF_ATTR_BPF_FD
195 obj_manage(BPF_OBJ_PIN);
196 printf("bpf(BPF_OBJ_PIN"
197 ", {pathname=\"/sys/fs/bpf/foo/bar\", bpf_fd=-1}, %u) = %s\n",
198 (unsigned) sizeof(union bpf_attr), errstr);
199 BOGUS_BPF(BPF_OBJ_PIN);
200
201 obj_manage(BPF_OBJ_GET);
202 printf("bpf(BPF_OBJ_GET"
203 ", {pathname=\"/sys/fs/bpf/foo/bar\", bpf_fd=-1}, %u) = %s\n",
204 (unsigned) sizeof(union bpf_attr), errstr);
205 BOGUS_BPF(BPF_OBJ_GET);
206 # endif
207
208 # ifdef HAVE_UNION_BPF_ATTR_ATTACH_TYPE
209 prog_cgroup(BPF_PROG_ATTACH);
210 printf("bpf(BPF_PROG_ATTACH"
211 ", {target_fd=-1, attach_bpf_fd=-1"
212 ", attach_type=BPF_CGROUP_INET_INGRESS}, %u) = %s\n",
213 (unsigned) sizeof(union bpf_attr), errstr);
214 BOGUS_BPF(BPF_PROG_ATTACH);
215
216 prog_cgroup(BPF_PROG_DETACH);
217 printf("bpf(BPF_PROG_DETACH"
218 ", {target_fd=-1, attach_type=BPF_CGROUP_INET_INGRESS}, %u)"
219 " = %s\n",
220 (unsigned) sizeof(union bpf_attr), errstr);
221 BOGUS_BPF(BPF_PROG_DETACH);
222 # endif
223
224 bogus_bpf(0xfacefeed, "0xfacefeed /* BPF_??? */");
225
226 puts("+++ exited with 0 +++");
227 return 0;
228 }
229
230 #else
231
232 SKIP_MAIN_UNDEFINED("__NR_bpf")
233
234 #endif
235