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 "process_vm.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 static int semid;
42
43 static void child_alloc(void);
44 static void child_invoke(void);
45 static void setup(void);
46 static void cleanup(void);
47
main(int argc,char ** argv)48 int main(int argc, char **argv)
49 {
50 int lc, status;
51
52 tst_parse_opts(argc, argv, NULL, NULL);
53
54 setup();
55 for (lc = 0; TEST_LOOPING(lc); lc++) {
56 tst_count = 0;
57 len = strlen(tst_string);
58
59 if (pipe(pipe_fd) < 0)
60 tst_brkm(TBROK | TERRNO, cleanup, "pipe");
61
62 /* the start of child_alloc and child_invoke is already
63 * synchronized via pipe */
64 pids[0] = fork();
65 switch (pids[0]) {
66 case -1:
67 tst_brkm(TBROK | TERRNO, cleanup, "fork #0");
68 case 0:
69 child_alloc();
70 exit(0);
71 }
72
73 pids[1] = fork();
74 switch (pids[1]) {
75 case -1:
76 tst_brkm(TBROK | TERRNO, cleanup, "fork #1");
77 case 0:
78 child_invoke();
79 exit(0);
80 }
81
82 /* wait until child_invoke reads from child_alloc's VM */
83 if (waitpid(pids[1], &status, 0) == -1)
84 tst_brkm(TBROK | TERRNO, cleanup, "waitpid");
85 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
86 tst_resm(TFAIL, "child 1 returns %d", status);
87
88 /* child_alloc is free to exit now */
89 safe_semop(semid, 0, 1);
90
91 if (waitpid(pids[0], &status, 0) == -1)
92 tst_brkm(TBROK | TERRNO, cleanup, "waitpid");
93 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
94 tst_resm(TFAIL, "child 0 returns %d", status);
95 }
96
97 cleanup();
98 tst_exit();
99 }
100
child_alloc(void)101 static void child_alloc(void)
102 {
103 char *foo;
104 char buf[BUFSIZ];
105
106 foo = SAFE_MALLOC(tst_exit, len + 1);
107 strncpy(foo, tst_string, len);
108 foo[len] = '\0';
109 tst_resm(TINFO, "child 0: memory allocated and initialized.");
110
111 /* passing addr of string "foo" via pipe */
112 SAFE_CLOSE(tst_exit, pipe_fd[0]);
113 snprintf(buf, BUFSIZ, "%p", foo);
114 SAFE_WRITE(tst_exit, 1, pipe_fd[1], buf, strlen(buf));
115 SAFE_CLOSE(tst_exit, pipe_fd[1]);
116
117 /* wait until child_invoke is done reading from our VM */
118 safe_semop(semid, 0, -1);
119 }
120
child_invoke(void)121 static void child_invoke(void)
122 {
123 char *lp, *rp;
124 char buf[BUFSIZ];
125 struct iovec local, remote;
126
127 /* get addr from pipe */
128 SAFE_CLOSE(tst_exit, pipe_fd[1]);
129 SAFE_READ(tst_exit, 0, pipe_fd[0], buf, BUFSIZ);
130 SAFE_CLOSE(tst_exit, pipe_fd[0]);
131 if (sscanf(buf, "%p", &rp) != 1)
132 tst_brkm(TBROK | TERRNO, tst_exit, "sscanf");
133
134 lp = SAFE_MALLOC(tst_exit, len + 1);
135 local.iov_base = lp;
136 local.iov_len = len;
137 remote.iov_base = rp;
138 remote.iov_len = len;
139
140 tst_resm(TINFO, "child 1: reading string from same memory location.");
141 TEST(test_process_vm_readv(pids[0], &local, 1, &remote, 1, 0));
142 if (TEST_RETURN != len)
143 tst_brkm(TFAIL | TERRNO, tst_exit, "process_vm_readv");
144 if (strncmp(lp, tst_string, len) != 0)
145 tst_brkm(TFAIL, tst_exit, "child 1: expected string: %s, "
146 "received string: %256s", tst_string, lp);
147 else
148 tst_resm(TPASS, "expected string received.");
149 }
150
setup(void)151 static void setup(void)
152 {
153 tst_require_root();
154
155 #if !defined(__NR_process_vm_readv)
156 tst_brkm(TCONF, NULL, "process_vm_readv does not exist "
157 "on your system");
158 #endif
159 semid = init_sem(1);
160
161 TEST_PAUSE;
162 }
163
cleanup(void)164 static void cleanup(void)
165 {
166 clean_sem(semid);
167 }
168