1 /*
2 * Check decoding of process_vm_readv/process_vm_writev syscall.
3 *
4 * Copyright (c) 2016 Eugene Syromyatnikov <evgsyr@gmail.com>
5 * Copyright (c) 2016-2018 The strace developers.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include <inttypes.h>
32 #include <stdio.h>
33 #include <unistd.h>
34 #include <sys/uio.h>
35
36 #if OP_WR
37 # define in_iovec rmt_iovec
38 # define out_iovec lcl_iovec
39 # define in_iov rmt_iov
40 # define out_iov lcl_iov
41 #else
42 # define in_iovec lcl_iovec
43 # define out_iovec rmt_iovec
44 # define in_iov lcl_iov
45 # define out_iov rmt_iov
46 #endif
47
48 typedef void (*iov_print_fn)(const struct iovec *, const void *, long);
49
50 enum { MAX_SEGM_COUNT = 2, MAX_STR_LEN = 5 };
51
52 struct print_iov_arg {
53 uint32_t count;
54 uint32_t valid :1,
55 string :1,
56 addr_term:1,
57 check_rc :1;
58 uint32_t str_segms;
59 uint8_t str_base[MAX_SEGM_COUNT];
60 uint8_t str_size[MAX_SEGM_COUNT];
61 };
62
63 static void
print_iov(const struct iovec * iov,const void * arg_ptr,long rc)64 print_iov(const struct iovec *iov, const void *arg_ptr, long rc)
65 {
66 const struct print_iov_arg *arg = arg_ptr;
67 uint32_t i;
68 uint32_t num_segm = 0;
69 uint64_t segm_offs = 0;
70
71 if (!arg || !arg->valid) {
72 if (iov)
73 printf("%p", iov);
74 else
75 printf("NULL");
76
77 return;
78 }
79
80 printf("[");
81
82 for (i = 0; i < arg->count; i++) {
83 if (i)
84 printf(", ");
85
86 if (i >= MAX_STR_LEN) {
87 printf("...");
88 break;
89 }
90
91 printf("{iov_base=");
92 if (arg->string && (!arg->check_rc || (rc != -1))) {
93 uint64_t str_left = iov[i].iov_len;
94 uint64_t pr_count = 0;
95
96 printf("\"");
97
98 while (str_left--) {
99 static const char oct_str[] = "01234567";
100 uint8_t c = arg->str_base[num_segm] + segm_offs;
101
102 if ((num_segm >= arg->str_segms) ||
103 (num_segm >= MAX_SEGM_COUNT))
104 error_msg_and_fail("print_iov: segment "
105 "count overrun");
106
107 if (pr_count++ < MAX_STR_LEN)
108 printf("\\%.1s%.1s%d",
109 (c >> 6) ?
110 oct_str + (c >> 6) : "",
111 (c >> 3) ?
112 oct_str + ((c >> 3) & 7) : "",
113 c & 7);
114
115 segm_offs++;
116
117 if (segm_offs >= arg->str_size[num_segm]) {
118 num_segm++;
119 segm_offs = 0;
120 }
121 }
122
123 printf("\"");
124
125 if (pr_count > MAX_STR_LEN)
126 printf("...");
127 } else {
128 if (iov[i].iov_base)
129 printf("%p", iov[i].iov_base);
130 else
131 printf("NULL");
132 }
133
134 printf(", iov_len=%zu}", iov[i].iov_len);
135 }
136
137 if (arg->addr_term)
138 printf(", ... /* %p */", iov + arg->count);
139
140 printf("]");
141 }
142
143 static void
do_call(kernel_ulong_t pid,kernel_ulong_t local_iov,const char * local_arg,kernel_ulong_t liovcnt,kernel_ulong_t remote_iov,const char * remote_arg,kernel_ulong_t riovcnt,kernel_ulong_t flags,iov_print_fn pr_iov)144 do_call(kernel_ulong_t pid,
145 kernel_ulong_t local_iov, const char *local_arg,
146 kernel_ulong_t liovcnt,
147 kernel_ulong_t remote_iov, const char *remote_arg,
148 kernel_ulong_t riovcnt,
149 kernel_ulong_t flags, iov_print_fn pr_iov)
150 {
151 long rc;
152 const char *errstr;
153
154 rc = syscall(OP_NR, pid, local_iov, liovcnt, remote_iov, riovcnt,
155 flags);
156 errstr = sprintrc(rc);
157
158 printf("%s(%d, ", OP_STR, (int) pid);
159
160 if (pr_iov)
161 pr_iov((const struct iovec *) (uintptr_t) local_iov, local_arg,
162 rc);
163 else
164 printf("%s", local_arg);
165
166 printf(", %lu, ", (unsigned long) liovcnt);
167
168 if (pr_iov)
169 pr_iov((const struct iovec *) (uintptr_t) remote_iov,
170 remote_arg, rc);
171 else
172 printf("%s", remote_arg);
173
174 printf(", %lu, %lu) = %s\n", (unsigned long) riovcnt,
175 (unsigned long) flags, errstr);
176 }
177
178 kernel_ulong_t
ptr_cast(void * ptr)179 ptr_cast(void *ptr)
180 {
181 return (kernel_ulong_t) (uintptr_t) ptr;
182 }
183
184 int
main(void)185 main(void)
186 {
187 enum {
188 SIZE_11 = 2,
189 SIZE_12 = 3,
190 SIZE_13 = 4,
191 SIZE_1 = SIZE_11 + SIZE_12 + SIZE_13,
192 SIZE_21 = 5,
193 SIZE_22 = 6,
194 SIZE_23 = 7,
195 SIZE_2 = SIZE_21 + SIZE_22 + SIZE_23,
196 };
197
198 enum {
199 SEGM1_BASE = 0x80,
200 SEGM2_BASE = 0xA0,
201 };
202
203 static const kernel_ulong_t bogus_pid =
204 (kernel_ulong_t) 0xbadfaceddeadca57ULL;
205 static const kernel_ulong_t bogus_iovcnt1 =
206 (kernel_ulong_t) 0xdec0ded1defaced2ULL;
207 static const kernel_ulong_t bogus_iovcnt2 =
208 (kernel_ulong_t) 0xdec0ded3defaced4ULL;
209 static const kernel_ulong_t bogus_flags =
210 (kernel_ulong_t) 0xdeadc0deda7adeadULL;
211
212 pid_t my_pid = getpid();
213 char *data1_out = tail_alloc(SIZE_1);
214 char *data2_out = tail_alloc(SIZE_2);
215 char *data1_in = tail_alloc(SIZE_2);
216 char *data2_in = tail_alloc(SIZE_1);
217
218 struct iovec bogus_iovec[] = {
219 { data1_out + SIZE_1, (size_t) 0xdeadfaceca57beefULL },
220 { data1_in + SIZE_2, (size_t) 0xbadc0dedda7adeadULL },
221 { data2_out + SIZE_2, (size_t) 0xf157facedec0ded1ULL },
222 { data2_in + SIZE_1, (size_t) 0xdefaced2bea7be57ULL },
223 };
224
225 struct iovec out_iovec[] = {
226 { data1_out, SIZE_11 },
227 { data1_out + SIZE_11, SIZE_12 },
228 { data1_out + SIZE_11 + SIZE_12, SIZE_13 },
229 { data2_out, SIZE_21 },
230 { data2_out + SIZE_21, SIZE_22 },
231 { data2_out + SIZE_21 + SIZE_22, SIZE_23 },
232 };
233 struct iovec in_iovec[] = {
234 { data1_in, SIZE_23 },
235 { data1_in + SIZE_23, SIZE_22 },
236 { data1_in + SIZE_23 + SIZE_22, SIZE_21 },
237 { data2_in, SIZE_13 },
238 { data2_in + SIZE_13, SIZE_12 },
239 { data2_in + SIZE_13 + SIZE_12, SIZE_11 },
240 };
241
242 struct iovec *bogus_iov = tail_memdup(bogus_iovec, sizeof(bogus_iovec));
243 struct iovec *lcl_iov = tail_memdup(lcl_iovec, sizeof(lcl_iovec));
244 struct iovec *rmt_iov = tail_memdup(rmt_iovec, sizeof(rmt_iovec));
245
246 struct print_iov_arg bogus_arg = { ARRAY_SIZE(bogus_iovec), 1 };
247 struct print_iov_arg lcl_arg = { ARRAY_SIZE(lcl_iovec), 1, 1, 0, 0,
248 2, {SEGM1_BASE, SEGM2_BASE}, {SIZE_1, SIZE_2} };
249 struct print_iov_arg rmt_arg = { ARRAY_SIZE(rmt_iovec), 1 };
250
251 struct print_iov_arg bogus_arg_cut = {
252 ARRAY_SIZE(bogus_iovec) - 2, 1, 0, 1
253 };
254 struct print_iov_arg lcl_arg_cut = {
255 ARRAY_SIZE(lcl_iovec) - 2, 1, 1, 1, 0, 2,
256 { SEGM1_BASE + SIZE_11 + SIZE_12, SEGM2_BASE },
257 {SIZE_13, SIZE_2}
258 };
259 struct print_iov_arg rmt_arg_cut = { ARRAY_SIZE(rmt_iovec) - 2, 1 };
260
261
262 fill_memory_ex(data1_out, SIZE_1, SEGM1_BASE, SIZE_1);
263 fill_memory_ex(data2_out, SIZE_2, SEGM2_BASE, SIZE_2);
264
265
266 do_call(bogus_pid, (kernel_ulong_t) (uintptr_t) ARG_STR(NULL),
267 bogus_iovcnt1, (kernel_ulong_t) (uintptr_t) ARG_STR(NULL),
268 bogus_iovcnt2, bogus_flags, NULL);
269
270 do_call(my_pid, ptr_cast(bogus_iov + ARRAY_SIZE(bogus_iovec)),
271 "[]", 0, ptr_cast(in_iov + ARRAY_SIZE(in_iovec)), "[]",
272 0, 0, NULL);
273 do_call(my_pid, ptr_cast(bogus_iov + ARRAY_SIZE(bogus_iovec)), NULL,
274 bogus_iovcnt1, ptr_cast(in_iov + ARRAY_SIZE(in_iovec)), NULL,
275 bogus_iovcnt2, 0, print_iov);
276
277 do_call(my_pid, ptr_cast(bogus_iov), (char *) &bogus_arg,
278 ARRAY_SIZE(bogus_iovec), ptr_cast(rmt_iov + 2),
279 (char *) &rmt_arg_cut, ARRAY_SIZE(rmt_iovec) - 2, 0, print_iov);
280
281 #if !OP_WR
282 lcl_arg.check_rc = 1;
283 lcl_arg_cut.check_rc = 1;
284 #endif
285
286 do_call(my_pid, ptr_cast(lcl_iov + 2), (char *) &lcl_arg_cut,
287 ARRAY_SIZE(lcl_iovec) - 1, ptr_cast(bogus_iov + 2),
288 (char *) &bogus_arg_cut, ARRAY_SIZE(bogus_iovec) - 1, 0,
289 print_iov);
290
291 lcl_arg_cut.addr_term = 0;
292
293 rmt_arg_cut.addr_term = 1;
294 rmt_arg_cut.count = 5;
295
296 do_call(my_pid, ptr_cast(lcl_iov + 2), (char *) &lcl_arg_cut,
297 ARRAY_SIZE(lcl_iovec) - 2, ptr_cast(rmt_iov + 1),
298 (char *) &rmt_arg_cut, ARRAY_SIZE(rmt_iovec), 0, print_iov);
299
300 /* Correct call */
301 do_call(my_pid, ptr_cast(lcl_iov), (char *) &lcl_arg,
302 ARRAY_SIZE(lcl_iovec), ptr_cast(rmt_iov), (char *) &rmt_arg,
303 ARRAY_SIZE(rmt_iovec), 0, print_iov);
304
305 puts("+++ exited with 0 +++");
306
307 return 0;
308 }
309