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 errno = 0;
70
71 if (child_pid == 0) {
72 pthread_t thread;
73 ret = pthread_create(&thread, NULL, thread_main, NULL);
74 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_create()");
75
76 if (exec_mode == EXEC_FIRST) {
77 ret = dprintf(fd[1], "Hi!");
78 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "dprintf()");
79
80 do_exec();
81 }
82
83 while (1) {
84 }
85 } else {
86 char buffer[4] = "";
87 ret = read(fd[0], buffer, sizeof(buffer));
88 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "read()");
89
90 T_LOG("mode: %d, %d: Parent[%d]: got: '%s' from execing child, trying to kill and wait\n",
91 kill_mode, exec_mode, getpid(), buffer);
92
93 int killcount = 0, status = 0, waitedpid = 0;
94
95 switch (kill_mode) {
96 case KILL_ONCE:
97 ret = kill(child_pid, SIGKILL);
98 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kill()");
99
100 waitedpid = waitpid(child_pid, &status, 0);
101
102 T_QUIET; T_ASSERT_POSIX_SUCCESS(waitedpid, "waitpid()");
103
104 killcount++;
105 break;
106 case KILL_MANY:
107 while (waitedpid == 0) {
108 ret = kill(child_pid, SIGKILL);
109 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kill()");
110
111 waitedpid = waitpid(child_pid, &status, WNOHANG);
112 T_QUIET; T_ASSERT_POSIX_SUCCESS(waitedpid, "waitpid()");
113
114 killcount++;
115 }
116 break;
117 default:
118 break;
119 }
120
121 T_LOG("mode: %d, %d: Parent[%d]: waitpid returned: %d, errno %d (%s), exit signal %d, after %d loops\n",
122 kill_mode, exec_mode, getpid(), waitedpid, errno, strerror(errno), WTERMSIG(status), killcount);
123 }
124 }
125
126 T_DECL(exec_exit_race_once_first, "Exec-exit race, one kill, exec on first thread") {
127 int rv = pipe(fd);
128 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
129
130 kill_mode = KILL_ONCE;
131 exec_mode = EXEC_FIRST;
132
133 for (int i = 0; i < 1000; i++) {
134 run_test();
135 }
136 }
137
138 T_DECL(exec_exit_race_many_first, "Exec-exit race, many kill, exec on first thread") {
139 int rv = pipe(fd);
140 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
141
142 kill_mode = KILL_MANY;
143 exec_mode = EXEC_FIRST;
144
145 for (int i = 0; i < 1000; i++) {
146 run_test();
147 }
148 }
149
150 T_DECL(exec_exit_race_once_second, "Exec-exit race, one kill, exec on second thread") {
151 int rv = pipe(fd);
152 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
153
154 kill_mode = KILL_ONCE;
155 exec_mode = EXEC_SECOND;
156
157 for (int i = 0; i < 1000; i++) {
158 run_test();
159 }
160 }
161
162 T_DECL(exec_exit_race_many_second, "Exec-exit race, many kill, exec on second thread") {
163 int rv = pipe(fd);
164 T_QUIET; T_ASSERT_POSIX_SUCCESS(rv, "pipe()");
165
166 kill_mode = KILL_MANY;
167 exec_mode = EXEC_SECOND;
168
169 for (int i = 0; i < 1000; i++) {
170 run_test();
171 }
172 }
173