1 /*
2 * Check decoding of threads when a non-leader thread invokes execve.
3 *
4 * Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include "tests.h"
31 #include <asm/unistd.h>
32 #include <errno.h>
33 #include <pthread.h>
34 #include <signal.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <time.h>
38 #include <unistd.h>
39
40 static pid_t leader;
41 static pid_t tid;
42
43 static void
handler(int signo)44 handler(int signo)
45 {
46 }
47
48 static unsigned int sigsetsize;
49 static long
k_sigsuspend(const sigset_t * const set)50 k_sigsuspend(const sigset_t *const set)
51 {
52 return syscall(__NR_rt_sigsuspend, set, sigsetsize);
53 }
54
55 static pid_t
k_gettid(void)56 k_gettid(void)
57 {
58 return syscall(__NR_gettid);
59 }
60
61 static void
get_sigsetsize(void)62 get_sigsetsize(void)
63 {
64 static const struct sigaction sa = { .sa_handler = handler };
65 if (sigaction(SIGUSR1, &sa, NULL))
66 perror_msg_and_fail("sigaction");
67
68 sigset_t mask;
69 sigemptyset(&mask);
70 sigaddset(&mask, SIGUSR1);
71 if (sigprocmask(SIG_BLOCK, &mask, NULL))
72 perror_msg_and_fail("sigprocmask");
73
74 raise(SIGUSR1);
75
76 sigemptyset(&mask);
77 for (sigsetsize = sizeof(mask) / sizeof(long);
78 sigsetsize; sigsetsize >>= 1) {
79 long rc = k_sigsuspend(&mask);
80 if (!rc)
81 error_msg_and_fail("rt_sigsuspend");
82 if (EINTR == errno)
83 break;
84 printf("%-5d rt_sigsuspend(%p, %u) = %s\n",
85 leader, &mask, sigsetsize, sprintrc(rc));
86 }
87 if (!sigsetsize)
88 perror_msg_and_fail("rt_sigsuspend");
89 printf("%-5d rt_sigsuspend([], %u) = ? ERESTARTNOHAND"
90 " (To be restarted if no handler)\n", leader, sigsetsize);
91 }
92
93 enum {
94 ACTION_exit = 0,
95 ACTION_rt_sigsuspend,
96 ACTION_nanosleep,
97 NUMBER_OF_ACTIONS
98 };
99
100 static const unsigned int NUMBER_OF_ITERATIONS = 1;
101 static unsigned int action;
102 static int fds[2];
103
104 static unsigned int
arglen(char ** args)105 arglen(char **args)
106 {
107 char **p;
108
109 for (p = args; *p; ++p)
110 ;
111
112 return p - args;
113 }
114
115 static void *
thread(void * arg)116 thread(void *arg)
117 {
118 tid = k_gettid();
119
120 static char buf[sizeof(action) * 3];
121 sprintf(buf, "%u", action + 1);
122
123 char **argv = arg;
124 argv[2] = buf;
125
126 if (read(fds[0], fds, sizeof(fds[0])))
127 perror_msg_and_fail("execve");
128
129 struct timespec ts = { .tv_nsec = 100000000 };
130 (void) clock_nanosleep(CLOCK_REALTIME, 0, &ts, NULL);
131
132 ts.tv_nsec = 12345;
133 printf("%-5d nanosleep({tv_sec=0, tv_nsec=%u}, NULL) = 0\n",
134 tid, (unsigned int) ts.tv_nsec);
135
136 switch (action % NUMBER_OF_ACTIONS) {
137 case ACTION_exit:
138 printf("%-5d execve(\"%s\", [\"%s\", \"%s\", \"%s\"]"
139 ", [/* %u vars */] <pid changed to %u ...>\n",
140 tid, argv[0], argv[0], argv[1], argv[2],
141 arglen(environ), leader);
142 break;
143 case ACTION_rt_sigsuspend:
144 printf("%-5d execve(\"%s\", [\"%s\", \"%s\", \"%s\"]"
145 ", [/* %u vars */] <unfinished ...>\n"
146 "%-5d <... rt_sigsuspend resumed>) = ?\n",
147 tid, argv[0], argv[0], argv[1], argv[2],
148 arglen(environ),
149 leader);
150 break;
151 case ACTION_nanosleep:
152 printf("%-5d execve(\"%s\", [\"%s\", \"%s\", \"%s\"]"
153 ", [/* %u vars */] <unfinished ...>\n"
154 "%-5d <... nanosleep resumed> <unfinished ...>)"
155 " = ?\n",
156 tid, argv[0], argv[0], argv[1], argv[2],
157 arglen(environ),
158 leader);
159 break;
160 }
161
162 printf("%-5d +++ superseded by execve in pid %u +++\n"
163 "%-5d <... execve resumed> ) = 0\n",
164 leader, tid,
165 leader);
166
167 (void) nanosleep(&ts, NULL);
168 execve(argv[0], argv, environ);
169 perror_msg_and_fail("execve");
170 }
171
172 int
main(int ac,char ** av)173 main(int ac, char **av)
174 {
175 setvbuf(stdout, NULL, _IONBF, 0);
176 leader = getpid();
177
178 if (ac < 3) {
179 struct timespec ts = { .tv_nsec = 1 };
180 if (clock_nanosleep(CLOCK_REALTIME, 0, &ts, NULL))
181 perror_msg_and_skip("clock_nanosleep CLOCK_REALTIME");
182
183 printf("%-5d execve(\"%s\", [\"%s\"], [/* %u vars */]) = 0\n",
184 leader, av[0], av[0], arglen(environ));
185
186 get_sigsetsize();
187 static char buf[sizeof(sigsetsize) * 3];
188 sprintf(buf, "%u", sigsetsize);
189
190 char *argv[] = { av[0], buf, (char *) "0", NULL };
191 printf("%-5d execve(\"%s\", [\"%s\", \"%s\", \"%s\"]"
192 ", [/* %u vars */]) = 0\n",
193 leader, argv[0], argv[0], argv[1], argv[2],
194 arglen(environ));
195 execve(argv[0], argv, environ);
196 perror_msg_and_fail("execve");
197 }
198
199 sigsetsize = atoi(av[1]);
200 action = atoi(av[2]);
201
202 if (action >= NUMBER_OF_ACTIONS * NUMBER_OF_ITERATIONS) {
203 printf("%-5d +++ exited with 0 +++\n", leader);
204 return 0;
205 }
206
207 if (pipe(fds))
208 perror_msg_and_fail("pipe");
209
210 pthread_t t;
211 errno = pthread_create(&t, NULL, thread, av);
212 if (errno)
213 perror_msg_and_fail("pthread_create");
214
215 struct timespec ts = { .tv_sec = 123 };
216 sigset_t mask;
217 sigemptyset(&mask);
218
219 static char leader_str[sizeof(leader) * 3];
220 int leader_str_len =
221 snprintf(leader_str, sizeof(leader_str), "%-5d", leader);
222
223 switch (action % NUMBER_OF_ACTIONS) {
224 case ACTION_exit:
225 printf("%s exit(42)%*s= ?\n", leader_str,
226 (int) sizeof(leader_str) - leader_str_len, " ");
227 close(fds[1]);
228 (void) syscall(__NR_exit, 42);
229 break;
230 case ACTION_rt_sigsuspend:
231 printf("%s rt_sigsuspend([], %u <unfinished ...>\n",
232 leader_str, sigsetsize);
233 close(fds[1]);
234 (void) k_sigsuspend(&mask);
235 break;
236 case ACTION_nanosleep:
237 printf("%s nanosleep({tv_sec=%u, tv_nsec=0}"
238 ", <unfinished ...>\n",
239 leader_str, (unsigned int) ts.tv_sec);
240 close(fds[1]);
241 (void) nanosleep(&ts, 0);
242 break;
243 }
244
245 return 1;
246 }
247