1 /*
2  * Check decoding of pread64 and pwrite64 syscalls.
3  *
4  * Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org>
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 "tests.h"
32 
33 #include <fcntl.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <unistd.h>
37 
38 static void
dump_str(const char * str,const unsigned int len)39 dump_str(const char *str, const unsigned int len)
40 {
41 	static const char dots[16] = "................";
42 	unsigned int i;
43 
44 	for (i = 0; i < len; i += 16) {
45 		unsigned int n = len - i > 16 ? 16 : len - i;
46 		const char *dump = hexdump_memdup(str + i, n);
47 
48 		tprintf(" | %05x %-49s  %-16.*s |\n",
49 			i, dump, n, dots);
50 
51 		free((void *) dump);
52 	}
53 }
54 
55 static void
print_hex(const char * str,const unsigned int len)56 print_hex(const char *str, const unsigned int len)
57 {
58 	const unsigned char *ustr = (const unsigned char *) str;
59 	unsigned int i;
60 
61 	for (i = 0; i < len; ++i) {
62 		unsigned int c = ustr[i];
63 
64 		switch (c) {
65 		case '\t':
66 			tprintf("\\t"); break;
67 		case '\n':
68 			tprintf("\\n"); break;
69 		case '\v':
70 			tprintf("\\v"); break;
71 		case '\f':
72 			tprintf("\\f"); break;
73 		case '\r':
74 			tprintf("\\r"); break;
75 		default:
76 			tprintf("\\%o", ustr[i]);
77 		}
78 	}
79 }
80 
81 static void
test_dump(const unsigned int len)82 test_dump(const unsigned int len)
83 {
84 	static char *buf;
85 
86 	if (buf) {
87 		size_t ps1 = get_page_size() - 1;
88 		buf = (void *) (((size_t) buf + ps1) & ~ps1) - len;
89 	} else {
90 		buf = tail_alloc(len);
91 	}
92 
93 	const off_t offset = 0xdefaceddeadbeefLL + len;
94 	long rc = pread(0, buf, len, offset);
95 	if (rc != (int) len)
96 		perror_msg_and_fail("pread64: expected %d, returned %ld",
97 				    len, rc);
98 
99 	tprintf("%s(%d, \"", "pread64", 0);
100 	print_hex(buf, len);
101 	tprintf("\", %d, %lld) = %ld\n", len, (long long) offset, rc);
102 	dump_str(buf, len);
103 
104 	unsigned int i;
105 	for (i = 0; i < len; ++i)
106 		buf[i] = i;
107 
108 	rc = pwrite(1, buf, len, offset);
109 	if (rc != (int) len)
110 		perror_msg_and_fail("pwrite64: expected %d, returned %ld",
111 				    len, rc);
112 
113 	tprintf("%s(%d, \"", "pwrite64", 1);
114 	print_hex(buf, len);
115 	tprintf("\", %d, %lld) = %ld\n", len, (long long) offset, rc);
116 	dump_str(buf, len);
117 
118 	if (!len)
119 		buf = 0;
120 }
121 
122 int
main(void)123 main(void)
124 {
125 	tprintf("%s", "");
126 
127 	skip_if_unavailable("/proc/self/fd/");
128 
129 	static const char tmp[] = "pread64-pwrite64-tmpfile";
130 	if (open(tmp, O_CREAT|O_RDONLY|O_TRUNC, 0600) != 0)
131 		perror_msg_and_fail("creat: %s", tmp);
132 	if (open(tmp, O_WRONLY) != 1)
133 		perror_msg_and_fail("open: %s", tmp);
134 
135 	char *nil = tail_alloc(1);
136 	*nil = '\0';
137 
138 	static const char w_c[] = "0123456789abcde";
139 	const unsigned int w_len = LENGTH_OF(w_c);
140 	const char *w_d = hexdump_strdup(w_c);
141 	const void *w = tail_memdup(w_c, w_len);
142 
143 	static const char r0_c[] = "01234567";
144 	const char *r0_d = hexdump_strdup(r0_c);
145 	const unsigned int r0_len = (w_len + 1) / 2;
146 	void *r0 = tail_alloc(r0_len);
147 
148 	static const char r1_c[] = "89abcde";
149 	const char *r1_d = hexdump_strdup(r1_c);
150 	const unsigned int r1_len = w_len - r0_len;
151 	void *r1 = tail_alloc(w_len);
152 
153 	void *efault = r1 - get_page_size();
154 
155 	long rc;
156 
157 	rc = pwrite(1, w, 0, 0);
158 	if (rc)
159 		perror_msg_and_fail("pwrite64: expected 0, returned %ld", rc);
160 	tprintf("pwrite64(1, \"\", 0, 0) = 0\n");
161 
162 	rc = pwrite(1, efault, 1, 0);
163 	if (rc != -1)
164 		perror_msg_and_fail("pwrite64: expected -1 EFAULT"
165 				    ", returned %ld", rc);
166 	tprintf("pwrite64(1, %p, 1, 0) = -1 EFAULT (%m)\n", efault);
167 
168 	rc = pwrite(1, nil, 1, -3);
169 	if (rc != -1)
170 		perror_msg_and_fail("pwrite64: expected -1, returned %ld", rc);
171 	tprintf("pwrite64(1, \"\\0\", 1, -3) = -1 EINVAL (%m)\n");
172 	dump_str(nil, 1);
173 
174 	rc = pwrite(1, w, w_len, 0);
175 	if (rc != (int) w_len)
176 		perror_msg_and_fail("pwrite64: expected %u, returned %ld",
177 				    w_len, rc);
178 	tprintf("pwrite64(1, \"%s\", %u, 0) = %ld\n"
179 		" | 00000 %-49s  %-16s |\n",
180 		w_c, w_len, rc, w_d, w_c);
181 	close(1);
182 
183 	rc = pread(0, r0, 0, 0);
184 	if (rc)
185 		perror_msg_and_fail("pread64: expected 0, returned %ld", rc);
186 	tprintf("pread64(0, \"\", 0, 0) = 0\n");
187 
188 	rc = pread(0, efault, 1, 0);
189 	if (rc != -1)
190 		perror_msg_and_fail("pread64: expected -1, returned %ld", rc);
191 	tprintf("pread64(0, %p, 1, 0) = -1 EFAULT (%m)\n", efault);
192 
193 	rc = pread(0, efault, 2, -7);
194 	if (rc != -1)
195 		perror_msg_and_fail("pread64: expected -1, returned %ld", rc);
196 	tprintf("pread64(0, %p, 2, -7) = -1 EINVAL (%m)\n", efault);
197 
198 	rc = pread(0, r0, r0_len, 0);
199 	if (rc != (int) r0_len)
200 		perror_msg_and_fail("pread64: expected %u, returned %ld",
201 				    r0_len, rc);
202 	tprintf("pread64(0, \"%s\", %u, 0) = %ld\n"
203 		" | 00000 %-49s  %-16s |\n",
204 		r0_c, r0_len, rc, r0_d, r0_c);
205 
206 	rc = pread(0, r1, w_len, r0_len);
207 	if (rc != (int) r1_len)
208 		perror_msg_and_fail("pread64: expected %u, returned %ld",
209 				    r1_len, rc);
210 	tprintf("pread64(0, \"%s\", %u, %u) = %ld\n"
211 		" | 00000 %-49s  %-16s |\n",
212 		r1_c, w_len, r0_len, rc, r1_d, r1_c);
213 	close(0);
214 
215 	if (open("/dev/zero", O_RDONLY))
216 		perror_msg_and_fail("open");
217 
218 	if (open("/dev/null", O_WRONLY) != 1)
219 		perror_msg_and_fail("open");
220 
221 	unsigned int i;
222 	for (i = 0; i <= 32; ++i)
223 		test_dump(i);
224 
225 	tprintf("+++ exited with 0 +++\n");
226 	return 0;
227 }
228