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1 /*
2  * Check decoding of preadv2 and pwritev2 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 #include <asm/unistd.h>
33 #include "scno.h"
34 
35 #if defined __NR_preadv2 && defined __NR_pwritev2
36 
37 # include <errno.h>
38 # include <fcntl.h>
39 # include <stdio.h>
40 # include <sys/uio.h>
41 # include <unistd.h>
42 
43 static int
pr(const int fd,const struct iovec * const vec,const unsigned long vlen,const unsigned long pos)44 pr(const int fd, const struct iovec *const vec,
45    const unsigned long vlen, const unsigned long pos)
46 {
47 	return syscall(__NR_preadv2, fd, vec, vlen, pos, 0L, 0L);
48 }
49 
50 static int
pw(const int fd,const struct iovec * const vec,const unsigned long vlen,const unsigned long pos)51 pw(const int fd, const struct iovec *const vec,
52    const unsigned long vlen, const unsigned long pos)
53 {
54 	return syscall(__NR_pwritev2, fd, vec, vlen, pos, 0L, 0L);
55 }
56 
57 static void
dumpio(void)58 dumpio(void)
59 {
60 	static char tmp[] = "preadv2-pwritev2-tmpfile";
61 	if (open(tmp, O_CREAT|O_RDONLY|O_TRUNC, 0600) != 0)
62 		perror_msg_and_fail("creat: %s", tmp);
63 	if (open(tmp, O_WRONLY) != 1)
64 		perror_msg_and_fail("open: %s", tmp);
65 	if (unlink(tmp))
66 		perror_msg_and_fail("unlink: %s", tmp);
67 
68 	static const char w0_c[] = "012";
69 	const char *w0_d = hexdump_strdup(w0_c);
70 	void *w0 = tail_memdup(w0_c, LENGTH_OF(w0_c));
71 
72 	static const char w1_c[] = "34567";
73 	const char *w1_d = hexdump_strdup(w1_c);
74 	void *w1 = tail_memdup(w1_c, LENGTH_OF(w1_c));
75 
76 	static const char w2_c[] = "89abcde";
77 	const char *w2_d = hexdump_strdup(w2_c);
78 	void *w2 = tail_memdup(w2_c, LENGTH_OF(w2_c));
79 
80 	long rc;
81 
82 	static const char r0_c[] = "01234567";
83 	const char *r0_d = hexdump_strdup(r0_c);
84 	static const char r1_c[] = "89abcde";
85 	const char *r1_d = hexdump_strdup(r1_c);
86 
87 	const struct iovec w_iov_[] = {
88 		{
89 			.iov_base = w0,
90 			.iov_len = LENGTH_OF(w0_c)
91 		}, {
92 			.iov_base = w1,
93 			.iov_len = LENGTH_OF(w1_c)
94 		}, {
95 			.iov_base = w2,
96 			.iov_len = LENGTH_OF(w2_c)
97 		}
98 	};
99 	const struct iovec *w_iov = tail_memdup(w_iov_, sizeof(w_iov_));
100 
101 	rc = pw(1, w_iov, 0, 0);
102 	if (rc)
103 		perror_msg_and_fail("pwritev2: expected 0, returned %ld", rc);
104 	tprintf("pwritev2(1, [], 0, 0, 0) = 0\n");
105 
106 	rc = pw(1, w_iov + ARRAY_SIZE(w_iov_) - 1, 2, 0);
107 	tprintf("pwritev2(1, [{iov_base=\"%s\", iov_len=%u}, ... /* %p */], 2, 0, 0)"
108 		" = %ld %s (%m)\n",
109 		w2_c, LENGTH_OF(w2_c), w_iov + ARRAY_SIZE(w_iov_),
110 		rc, errno2name());
111 
112 	const unsigned int w_len =
113 		LENGTH_OF(w0_c) + LENGTH_OF(w1_c) + LENGTH_OF(w2_c);
114 
115 	rc = pw(1, w_iov, ARRAY_SIZE(w_iov_), 0);
116 	if (rc != (int) w_len)
117 		perror_msg_and_fail("pwritev2: expected %u, returned %ld",
118 				    w_len, rc);
119 	close(1);
120 	tprintf("pwritev2(1, [{iov_base=\"%s\", iov_len=%u}"
121 		", {iov_base=\"%s\", iov_len=%u}"
122 		", {iov_base=\"%s\", iov_len=%u}], %u, 0, 0) = %u\n"
123 		" * %u bytes in buffer 0\n"
124 		" | 00000 %-49s  %-16s |\n"
125 		" * %u bytes in buffer 1\n"
126 		" | 00000 %-49s  %-16s |\n"
127 		" * %u bytes in buffer 2\n"
128 		" | 00000 %-49s  %-16s |\n",
129 		w0_c, LENGTH_OF(w0_c), w1_c, LENGTH_OF(w1_c),
130 		w2_c, LENGTH_OF(w2_c), (unsigned int) ARRAY_SIZE(w_iov_), w_len,
131 		LENGTH_OF(w0_c), w0_d, w0_c,
132 		LENGTH_OF(w1_c), w1_d, w1_c, LENGTH_OF(w2_c), w2_d, w2_c);
133 
134 	const unsigned int r_len = (w_len + 1) / 2;
135 	void *r0 = tail_alloc(r_len);
136 	const struct iovec r0_iov_[] = {
137 		{
138 			.iov_base = r0,
139 			.iov_len = r_len
140 		}
141 	};
142 	const struct iovec *r_iov = tail_memdup(r0_iov_, sizeof(r0_iov_));
143 
144 	rc = pr(0, r_iov, ARRAY_SIZE(r0_iov_), 0);
145 	if (rc != (int) r_len)
146 		perror_msg_and_fail("preadv2: expected %u, returned %ld",
147 				    r_len, rc);
148 	tprintf("preadv2(0, [{iov_base=\"%s\", iov_len=%u}], %u, 0, 0) = %u\n"
149 		" * %u bytes in buffer 0\n"
150 		" | 00000 %-49s  %-16s |\n",
151 		r0_c, r_len, (unsigned int) ARRAY_SIZE(r0_iov_),
152 		r_len, r_len, r0_d, r0_c);
153 
154 	void *r1 = tail_alloc(r_len);
155 	void *r2 = tail_alloc(w_len);
156 	const struct iovec r1_iov_[] = {
157 		{
158 			.iov_base = r1,
159 			.iov_len = r_len
160 		},
161 		{
162 			.iov_base = r2,
163 			.iov_len = w_len
164 		}
165 	};
166 	r_iov = tail_memdup(r1_iov_, sizeof(r1_iov_));
167 
168 	rc = pr(0, r_iov, ARRAY_SIZE(r1_iov_), r_len);
169 	if (rc != (int) w_len - (int) r_len)
170 		perror_msg_and_fail("preadv2: expected %d, returned %ld",
171 				    (int) w_len - r_len, rc);
172 	tprintf("preadv2(0, [{iov_base=\"%s\", iov_len=%u}"
173 		", {iov_base=\"\", iov_len=%u}], %u, %u, 0) = %u\n"
174 		" * %u bytes in buffer 0\n"
175 		" | 00000 %-49s  %-16s |\n",
176 		r1_c, r_len, w_len, (unsigned int) ARRAY_SIZE(r1_iov_),
177 		r_len, w_len - r_len,
178 		w_len - r_len, r1_d, r1_c);
179 	close(0);
180 }
181 
182 int
main(void)183 main(void)
184 {
185 	const kernel_ulong_t vlen = (kernel_ulong_t) 0xfac1fed2dad3bef4ULL;
186 	const unsigned long long pos = 0x7ac5fed6dad7bef8;
187 	const kernel_ulong_t pos_l = (kernel_ulong_t) pos;
188 	long rc;
189 	int test_dumpio;
190 
191 	tprintf("%s", "");
192 
193 #if defined __x86_64__ && defined __ILP32__
194 	/*
195 	 * x32 is the only architecture where preadv2 takes 5 arguments,
196 	 * see preadv64v2 in kernel sources.
197 	 */
198 	rc = syscall(__NR_preadv2, -1, NULL, vlen, pos_l, 1);
199 #else
200 	const kernel_ulong_t pos_h =
201 		(sizeof(pos_l) == sizeof(pos)) ?
202 		(kernel_ulong_t) 0xbadc0deddeadbeefULL :
203 		(kernel_ulong_t) (pos >> 32);
204 	rc = syscall(__NR_preadv2, -1, NULL, vlen, pos_l, pos_h, 1);
205 #endif
206 	if (rc != -1 || (ENOSYS != errno && EBADF != errno))
207 		perror_msg_and_fail("preadv2");
208 	test_dumpio = EBADF == errno;
209 	tprintf("preadv2(-1, NULL, %lu, %lld, RWF_HIPRI) = %s\n",
210 		(unsigned long) vlen, pos, sprintrc(rc));
211 
212 #if defined __x86_64__ && defined __ILP32__
213 	/*
214 	 * x32 is the only architecture where pwritev2 takes 5 arguments,
215 	 * see pwritev64v2 in kernel sources.
216 	 */
217 	rc = syscall(__NR_pwritev2, -1, NULL, vlen, pos_l, 1);
218 #else
219 	rc = syscall(__NR_pwritev2, -1, NULL, vlen, pos_l, pos_h, 1);
220 #endif
221 	if (rc != -1 || (ENOSYS != errno && EBADF != errno))
222 		perror_msg_and_fail("pwritev2");
223 	tprintf("pwritev2(-1, NULL, %lu, %lld, RWF_HIPRI) = %s\n",
224 		(unsigned long) vlen, pos, sprintrc(rc));
225 
226 	if (test_dumpio)
227 		dumpio();
228 
229 	tprintf("%s\n", "+++ exited with 0 +++");
230 	return 0;
231 }
232 
233 #else
234 
235 SKIP_MAIN_UNDEFINED("__NR_preadv2 && __NR_pwritev2")
236 
237 #endif
238