1 #include <assert.h>
2 #include <stdio.h>
3 #include <pthread.h>
4 #include <signal.h>
5 #include <unistd.h>
6 #include <errno.h>
7 #include <string.h>
8 #include <sys/wait.h>
9
10 #include <darwintest.h>
11
12 // rdar://58566604
13 // Exercise races of signal delivery vs exec in multi-threaded processes
14
15 T_GLOBAL_META(T_META_NAMESPACE("xnu.exec"),
16 T_META_CHECK_LEAKS(false),
17 T_META_ALL_VALID_ARCHS(true));
18
19 enum { KILL_ONCE, KILL_MANY, KILL_LAST } kill_mode;
20 enum { EXEC_FIRST, EXEC_SECOND, EXEC_LAST } exec_mode;
21
22 static int fd[2];
23
24 static void
do_exec(void)25 do_exec(void)
26 {
27 char echo_arg[50] = "";
28
29 snprintf(echo_arg, sizeof(echo_arg), " Child[%d] says hello after exec", getpid());
30
31 char * new_argv[] = {
32 "/bin/echo",
33 echo_arg,
34 NULL
35 };
36
37 int ret = execv(new_argv[0], new_argv);
38 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "execv()");
39 }
40
41 static void*
thread_main(void * arg)42 thread_main(void* arg)
43 {
44 T_LOG("mode: %d, %d: Child[%d] created second thread\n",
45 kill_mode, exec_mode, getpid());
46
47 if (exec_mode == EXEC_SECOND) {
48 int ret = dprintf(fd[1], "Hi!");
49 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "dprintf()");
50 do_exec();
51 }
52
53 while (1) {
54 }
55 return NULL;
56 }
57
58 void
run_test(void)59 run_test(void)
60 {
61 T_LOG("mode: %d, %d: Parent[%d]: forking\n",
62 kill_mode, exec_mode, getpid());
63
64 pid_t child_pid = fork();
65
66 T_QUIET; T_ASSERT_POSIX_SUCCESS(child_pid, "fork()");
67
68 int ret = 0;
69
70 if (child_pid == 0) {
71 pthread_t thread;
72 ret = pthread_create(&thread, NULL, thread_main, NULL);
73 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_create()");
74
75 if (exec_mode == EXEC_FIRST) {
76 ret = dprintf(fd[1], "Hi!");
77 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "dprintf()");
78
79 do_exec();
80 }
81
82 while (1) {
83 }
84 } else {
85 char buffer[4] = "";
86 ret = read(fd[0], buffer, sizeof(buffer));
87 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "read()");
88
89 T_LOG("mode: %d, %d: Parent[%d]: got: '%s' from execing child, trying to kill and wait\n",
90 kill_mode, exec_mode, getpid(), buffer);
91
92 int killcount = 0, status = 0, waitedpid = 0;
93
94 switch (kill_mode) {
95 case KILL_ONCE:
96 ret = kill(child_pid, SIGKILL);
97 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kill()");
98
99 waitedpid = waitpid(child_pid, &status, 0);
100
101 T_QUIET; T_ASSERT_POSIX_SUCCESS(waitedpid, "waitpid()");
102
103 killcount++;
104 break;
105 case KILL_MANY:
106 while (waitedpid == 0) {
107 ret = kill(child_pid, SIGKILL);
108 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kill()");
109
110 waitedpid = waitpid(child_pid, &status, WNOHANG);
111 T_QUIET; T_ASSERT_POSIX_SUCCESS(waitedpid, "waitpid()");
112
113 killcount++;
114 }
115 break;
116 default:
117 break;
118 }
119
120 T_LOG("mode: %d, %d: Parent[%d]: waitpid returned: %d, errno %d (%s), exit signal %d, after %d loops\n",
121 kill_mode, exec_mode, getpid(), waitedpid, errno, strerror(errno), WTERMSIG(status), killcount);
122 }
123 }
124
125 T_DECL(exec_exit_race_once_first, "Exec-exit race, one kill, exec on first thread") {
126 int rv = pipe(fd);
127 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
128
129 kill_mode = KILL_ONCE;
130 exec_mode = EXEC_FIRST;
131
132 for (int i = 0; i < 1000; i++) {
133 run_test();
134 }
135 }
136
137 T_DECL(exec_exit_race_many_first, "Exec-exit race, many kill, exec on first thread") {
138 int rv = pipe(fd);
139 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
140
141 kill_mode = KILL_MANY;
142 exec_mode = EXEC_FIRST;
143
144 for (int i = 0; i < 1000; i++) {
145 run_test();
146 }
147 }
148
149 T_DECL(exec_exit_race_once_second, "Exec-exit race, one kill, exec on second thread") {
150 int rv = pipe(fd);
151 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
152
153 kill_mode = KILL_ONCE;
154 exec_mode = EXEC_SECOND;
155
156 for (int i = 0; i < 1000; i++) {
157 run_test();
158 }
159 }
160
161 T_DECL(exec_exit_race_many_second, "Exec-exit race, many kill, exec on second thread") {
162 int rv = pipe(fd);
163 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
164
165 kill_mode = KILL_MANY;
166 exec_mode = EXEC_SECOND;
167
168 for (int i = 0; i < 1000; i++) {
169 run_test();
170 }
171 }
172