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
30 #include "test.h"
31 #include "safe_macros.h"
32 #include "lapi/syscalls.h"
33
34 char *TCID = "process_vm_readv02";
35 int TST_TOTAL = 1;
36
37 static char *tst_string = "THIS IS A TEST";
38 static int len;
39 static int pipe_fd[2];
40 static pid_t pids[2];
41
42 static void child_alloc(void);
43 static void child_invoke(void);
44 static void setup(void);
45 static void cleanup(void);
46
main(int argc,char ** argv)47 int main(int argc, char **argv)
48 {
49 int lc, status;
50
51 tst_parse_opts(argc, argv, NULL, NULL);
52
53 setup();
54 for (lc = 0; TEST_LOOPING(lc); lc++) {
55 tst_count = 0;
56 len = strlen(tst_string);
57
58 SAFE_PIPE(cleanup, pipe_fd);
59
60 /* the start of child_alloc and child_invoke is already
61 * synchronized via pipe */
62 pids[0] = fork();
63 switch (pids[0]) {
64 case -1:
65 tst_brkm(TBROK | TERRNO, cleanup, "fork #0");
66 case 0:
67 child_alloc();
68 exit(0);
69 }
70
71 pids[1] = fork();
72 switch (pids[1]) {
73 case -1:
74 tst_brkm(TBROK | TERRNO, cleanup, "fork #1");
75 case 0:
76 child_invoke();
77 exit(0);
78 }
79
80 /* wait until child_invoke reads from child_alloc's VM */
81 SAFE_WAITPID(cleanup, pids[1], &status, 0);
82 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
83 tst_resm(TFAIL, "child 1 returns %d", status);
84
85 /* child_alloc is free to exit now */
86 TST_SAFE_CHECKPOINT_WAKE(cleanup, 0);
87
88 SAFE_WAITPID(cleanup, pids[0], &status, 0);
89 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
90 tst_resm(TFAIL, "child 0 returns %d", status);
91 }
92
93 cleanup();
94 tst_exit();
95 }
96
child_alloc(void)97 static void child_alloc(void)
98 {
99 char *foo;
100 char buf[BUFSIZ];
101
102 foo = SAFE_MALLOC(tst_exit, len + 1);
103 strncpy(foo, tst_string, len);
104 foo[len] = '\0';
105 tst_resm(TINFO, "child 0: memory allocated and initialized.");
106
107 /* passing addr of string "foo" via pipe */
108 SAFE_CLOSE(tst_exit, pipe_fd[0]);
109 snprintf(buf, BUFSIZ, "%p", foo);
110 SAFE_WRITE(tst_exit, 1, pipe_fd[1], buf, strlen(buf) + 1);
111 SAFE_CLOSE(tst_exit, pipe_fd[1]);
112
113 /* wait until child_invoke is done reading from our VM */
114 TST_SAFE_CHECKPOINT_WAIT(cleanup, 0);
115 }
116
child_invoke(void)117 static void child_invoke(void)
118 {
119 char *lp, *rp;
120 char buf[BUFSIZ];
121 struct iovec local, remote;
122
123 /* get addr from pipe */
124 SAFE_CLOSE(tst_exit, pipe_fd[1]);
125 SAFE_READ(tst_exit, 0, pipe_fd[0], buf, BUFSIZ);
126 SAFE_CLOSE(tst_exit, pipe_fd[0]);
127 if (sscanf(buf, "%p", &rp) != 1)
128 tst_brkm(TBROK | TERRNO, tst_exit, "sscanf");
129
130 lp = SAFE_MALLOC(tst_exit, len + 1);
131 local.iov_base = lp;
132 local.iov_len = len;
133 remote.iov_base = rp;
134 remote.iov_len = len;
135
136 tst_resm(TINFO, "child 1: reading string from same memory location.");
137 TEST(ltp_syscall(__NR_process_vm_readv, pids[0],
138 &local, 1, &remote, 1, 0));
139 if (TEST_RETURN != len)
140 tst_brkm(TFAIL | TERRNO, tst_exit, "process_vm_readv");
141 if (strncmp(lp, tst_string, len) != 0)
142 tst_brkm(TFAIL, tst_exit, "child 1: expected string: %s, "
143 "received string: %256s", tst_string, lp);
144 else
145 tst_resm(TPASS, "expected string received.");
146 }
147
setup(void)148 static void setup(void)
149 {
150 tst_require_root();
151
152 /* Just a sanity check of the existence of syscall */
153 ltp_syscall(__NR_process_vm_readv, getpid(), NULL, 0, NULL, 0, 0);
154
155 tst_tmpdir();
156 TST_CHECKPOINT_INIT(cleanup);
157
158 TEST_PAUSE;
159 }
160
cleanup(void)161 static void cleanup(void)
162 {
163 tst_rmdir();
164 }
165