1 /*
2 * Copyright (c) International Business Machines Corp., 2012
3 * Copyright (c) Linux Test Project, 2012
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20 #define _GNU_SOURCE
21 #include <sys/types.h>
22 #include <sys/uio.h>
23 #include <sys/wait.h>
24 #include <errno.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <unistd.h>
29 #include <limits.h>
30
31 #include "test.h"
32 #include "safe_macros.h"
33 #include "lapi/syscalls.h"
34
35 char *TCID = "process_vm_writev02";
36 int TST_TOTAL = 1;
37
38 #define PADDING_SIZE 10
39 #define DEFAULT_CHAR 53
40
41 static int sflag;
42 static char *sz_opt;
43 static option_t options[] = {
44 {"s:", &sflag, &sz_opt},
45 {NULL, NULL, NULL}
46 };
47
48 static long bufsz;
49 static int pipe_fd[2];
50 static pid_t pids[2];
51
52 static void child_init_and_verify(void);
53 static void child_write(void);
54 static void setup(void);
55 static void cleanup(void);
56 static void help(void);
57
main(int argc,char ** argv)58 int main(int argc, char **argv)
59 {
60 int lc, status;
61
62 tst_parse_opts(argc, argv, options, &help);
63
64 setup();
65 for (lc = 0; TEST_LOOPING(lc); lc++) {
66 tst_count = 0;
67
68 SAFE_PIPE(cleanup, pipe_fd);
69
70 /* the start of child_init_and_verify and child_write is
71 * already synchronized via pipe */
72 pids[0] = fork();
73 switch (pids[0]) {
74 case -1:
75 tst_brkm(TBROK | TERRNO, cleanup, "fork #0");
76 case 0:
77 child_init_and_verify();
78 exit(0);
79 default:
80 break;
81 }
82
83 pids[1] = fork();
84 switch (pids[1]) {
85 case -1:
86 tst_brkm(TBROK | TERRNO, cleanup, "fork #1");
87 case 0:
88 child_write();
89 exit(0);
90 }
91
92 /* wait until child_write writes into
93 * child_init_and_verify's VM */
94 SAFE_WAITPID(cleanup, pids[1], &status, 0);
95 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
96 tst_resm(TFAIL, "child 1 returns %d", status);
97
98 /* signal child_init_and_verify to verify its VM now */
99 TST_SAFE_CHECKPOINT_WAKE(cleanup, 0);
100
101 SAFE_WAITPID(cleanup, pids[0], &status, 0);
102 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
103 tst_resm(TFAIL, "child 0 returns %d", status);
104 }
105
106 cleanup();
107 tst_exit();
108 }
109
child_init_and_verify(void)110 static void child_init_and_verify(void)
111 {
112 unsigned char *foo;
113 char buf[bufsz];
114 long i, nr_err;
115
116 foo = SAFE_MALLOC(tst_exit, bufsz);
117 for (i = 0; i < bufsz; i++)
118 foo[i] = DEFAULT_CHAR;
119 tst_resm(TINFO, "child 0: memory allocated.");
120
121 /* passing addr of string "foo" via pipe */
122 SAFE_CLOSE(tst_exit, pipe_fd[0]);
123 snprintf(buf, bufsz, "%p", foo);
124 SAFE_WRITE(tst_exit, 1, pipe_fd[1], buf, strlen(buf) + 1);
125 SAFE_CLOSE(tst_exit, pipe_fd[1]);
126
127 /* wait until child_write() is done writing to our VM */
128 TST_SAFE_CHECKPOINT_WAIT(cleanup, 0);
129
130 nr_err = 0;
131 for (i = 0; i < bufsz; i++) {
132 if (foo[i] != i % 256) {
133 #if DEBUG
134 tst_resm(TFAIL, "child 0: expected %i, got %i for "
135 "byte seq %ld", i % 256, foo[i], i);
136 #endif
137 nr_err++;
138 }
139 }
140 if (nr_err)
141 tst_brkm(TFAIL, tst_exit, "child 0: got %ld incorrect bytes.",
142 nr_err);
143 else
144 tst_resm(TPASS, "child 0: all bytes are expected.");
145 }
146
child_write(void)147 static void child_write(void)
148 {
149 unsigned char *lp, *rp;
150 char buf[bufsz];
151 struct iovec local, remote;
152 long i;
153
154 /* get addr from pipe */
155 SAFE_CLOSE(tst_exit, pipe_fd[1]);
156 SAFE_READ(tst_exit, 0, pipe_fd[0], buf, bufsz);
157 SAFE_CLOSE(tst_exit, pipe_fd[0]);
158 if (sscanf(buf, "%p", &rp) != 1)
159 tst_brkm(TBROK | TERRNO, tst_exit, "sscanf");
160
161 lp = SAFE_MALLOC(tst_exit, bufsz + PADDING_SIZE * 2);
162
163 for (i = 0; i < bufsz + PADDING_SIZE * 2; i++)
164 lp[i] = DEFAULT_CHAR;
165 for (i = 0; i < bufsz; i++)
166 lp[i + PADDING_SIZE] = i % 256;
167
168 local.iov_base = lp + PADDING_SIZE;
169 local.iov_len = bufsz;
170 remote.iov_base = rp;
171 remote.iov_len = bufsz;
172
173 tst_resm(TINFO, "child 2: write to the same memory location.");
174 TEST(ltp_syscall(__NR_process_vm_writev, pids[0], &local,
175 1UL, &remote, 1UL, 0UL));
176 if (TEST_RETURN != bufsz)
177 tst_brkm(TFAIL | TTERRNO, tst_exit, "process_vm_readv");
178 }
179
setup(void)180 static void setup(void)
181 {
182 tst_require_root();
183
184 /* Just a sanity check of the existence of syscall */
185 ltp_syscall(__NR_process_vm_writev, getpid(), NULL, 0UL, NULL, 0UL, 0UL);
186
187 bufsz =
188 sflag ? SAFE_STRTOL(NULL, sz_opt, 1, LONG_MAX - PADDING_SIZE * 2)
189 : 100000;
190
191 tst_tmpdir();
192 TST_CHECKPOINT_INIT(cleanup);
193
194 TEST_PAUSE;
195 }
196
cleanup(void)197 static void cleanup(void)
198 {
199 tst_rmdir();
200 }
201
help(void)202 static void help(void)
203 {
204 printf(" -s NUM Set the size of total buffer size.\n");
205 }
206