1 /* $NetBSD: t_clone.c,v 1.6 2024/09/27 18:50:01 riastradh Exp $ */
2
3 /*-
4 * Copyright (c) 2008 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __COPYRIGHT("@(#) Copyright (c) 2008\
34 The NetBSD Foundation, inc. All rights reserved.");
35 __RCSID("$NetBSD: t_clone.c,v 1.6 2024/09/27 18:50:01 riastradh Exp $");
36
37 #include <sys/param.h>
38 #include <sys/types.h>
39 #include <sys/mman.h>
40 #include <sys/resource.h>
41 #include <sys/wait.h>
42
43 #include <errno.h>
44 #include <sched.h>
45 #include <signal.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50
51 #include <atf-c.h>
52
53 #define STACKSIZE (8 * 1024)
54 #define FROBVAL 41973
55 #define CHILDEXIT 0xa5
56
57 static void *
getstack(void)58 getstack(void)
59 {
60 void *stack = mmap(NULL, STACKSIZE, PROT_READ|PROT_WRITE,
61 MAP_PRIVATE|MAP_ANON, -1, (off_t) 0);
62 ATF_REQUIRE_ERRNO(errno, stack != MAP_FAILED);
63 #ifndef __MACHINE_STACK_GROWS_UP
64 stack = (char *)stack + STACKSIZE;
65 #endif
66 return stack;
67 }
68
69 static void
putstack(void * stack)70 putstack(void *stack)
71 {
72 #ifndef __MACHINE_STACK_GROWS_UP
73 stack = (char *)stack - STACKSIZE;
74 #endif
75 ATF_REQUIRE_ERRNO(errno, munmap(stack, STACKSIZE) != -1);
76 }
77
78 static int
dummy(void * arg)79 dummy(void *arg)
80 {
81
82 return 0;
83 }
84
85 static int
clone_func(void * arg)86 clone_func(void *arg)
87 {
88 long *frobp = arg, diff;
89
90 printf("child: stack ~= %p, frobme = %p\n", &frobp, frobp);
91 fflush(stdout);
92
93 if (frobp[0] != getppid())
94 return 1;
95
96 if (frobp[0] == getpid())
97 return 2;
98
99 diff = labs(frobp[1] - (long) &frobp);
100
101 if (diff > 1024)
102 return 3;
103
104 frobp[1] = FROBVAL;
105
106 return (CHILDEXIT);
107 }
108
109 ATF_TC(clone_basic);
ATF_TC_HEAD(clone_basic,tc)110 ATF_TC_HEAD(clone_basic, tc)
111 {
112
113 atf_tc_set_md_var(tc, "descr", "Checks clone(2)");
114 }
115
ATF_TC_BODY(clone_basic,tc)116 ATF_TC_BODY(clone_basic, tc)
117 {
118 sigset_t mask;
119 void *stack = getstack();
120 pid_t pid;
121 volatile long frobme[2];
122 int stat;
123
124 printf("parent: stack = %p, frobme = %p\n", stack, frobme);
125 fflush(stdout);
126
127 frobme[0] = (long)getpid();
128 frobme[1] = (long)stack;
129
130 sigemptyset(&mask);
131 sigaddset(&mask, SIGUSR1);
132
133 ATF_REQUIRE_ERRNO(errno, sigprocmask(SIG_BLOCK, &mask, NULL) != -1);
134
135 switch (pid = __clone(clone_func, stack,
136 CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGUSR1,
137 __UNVOLATILE(frobme))) {
138 case 0:
139 atf_tc_fail("clone() returned 0");
140 /*NOTREACHED*/
141 case -1:
142 atf_tc_fail("clone() failed: %s", strerror(errno));
143 /*NOTREACHED*/
144 default:
145 while (waitpid(pid, &stat, __WCLONE) != pid)
146 continue;
147 }
148
149 ATF_REQUIRE_MSG(WIFEXITED(stat) != 0, "child didn't exit");
150
151 printf("parent: childexit = 0x%x, frobme = %ld\n",
152 WEXITSTATUS(stat), frobme[1]);
153
154 switch (WEXITSTATUS(stat)) {
155 case CHILDEXIT:
156 ATF_REQUIRE_EQ(frobme[1], FROBVAL);
157 break;
158 case 1:
159 atf_tc_fail("child: argument does not contain parent's pid");
160 /*NOTREACHED*/
161 case 2:
162 atf_tc_fail("child: called in parent's pid");
163 /*NOTREACHED*/
164 case 3:
165 atf_tc_fail("child: called with bad stack");
166 /*NOTREACHED*/
167 default:
168 atf_tc_fail("child returned unknown code: %d",
169 WEXITSTATUS(stat));
170 /*NOTREACHED*/
171 }
172
173 putstack(stack);
174 }
175
176 ATF_TC(clone_null_stack);
ATF_TC_HEAD(clone_null_stack,tc)177 ATF_TC_HEAD(clone_null_stack, tc)
178 {
179
180 atf_tc_set_md_var(tc, "descr",
181 "Checks that clone(2) fails when stack pointer is NULL");
182 }
183
ATF_TC_BODY(clone_null_stack,tc)184 ATF_TC_BODY(clone_null_stack, tc)
185 {
186 int rv;
187
188 rv = __clone(dummy, NULL,
189 CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGCHLD, NULL);
190
191 ATF_REQUIRE_EQ(rv, -1);
192 ATF_REQUIRE_EQ(errno, EINVAL);
193 }
194
195 ATF_TC(clone_null_func);
ATF_TC_HEAD(clone_null_func,tc)196 ATF_TC_HEAD(clone_null_func, tc)
197 {
198
199 atf_tc_set_md_var(tc, "descr",
200 "Checks that clone(2) fails when function pointer is NULL");
201 }
202
ATF_TC_BODY(clone_null_func,tc)203 ATF_TC_BODY(clone_null_func, tc)
204 {
205 void *stack = getstack();
206 int rv;
207
208
209 errno = 0;
210 rv = __clone(0, stack,
211 CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGCHLD, NULL);
212
213 ATF_REQUIRE_EQ(rv, -1);
214 ATF_REQUIRE_EQ(errno, EINVAL);
215
216 putstack(stack);
217 }
218
219 ATF_TC(clone_out_of_proc);
ATF_TC_HEAD(clone_out_of_proc,tc)220 ATF_TC_HEAD(clone_out_of_proc, tc)
221 {
222
223 atf_tc_set_md_var(tc, "descr",
224 "Checks that clone(2) fails when running out of processes");
225 atf_tc_set_md_var(tc, "require.user", "unprivileged");
226 }
227
ATF_TC_BODY(clone_out_of_proc,tc)228 ATF_TC_BODY(clone_out_of_proc, tc)
229 {
230 char *stack = getstack();
231 struct rlimit rl;
232 int rv;
233
234 ATF_REQUIRE_ERRNO(errno, getrlimit(RLIMIT_NPROC, &rl) != -1);
235
236 rl.rlim_cur = 0;
237 rl.rlim_max = 0;
238
239 ATF_REQUIRE_ERRNO(errno, setrlimit(RLIMIT_NPROC, &rl) != -1);
240
241 errno = 0;
242 rv = __clone(dummy, stack,
243 CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGCHLD, (void *)&rl);
244
245 ATF_REQUIRE_EQ(rv, -1);
246 ATF_REQUIRE_EQ(errno, EAGAIN);
247 putstack(stack);
248 }
249
ATF_TP_ADD_TCS(tp)250 ATF_TP_ADD_TCS(tp)
251 {
252
253 ATF_TP_ADD_TC(tp, clone_basic);
254 ATF_TP_ADD_TC(tp, clone_null_stack);
255 ATF_TP_ADD_TC(tp, clone_null_func);
256 ATF_TP_ADD_TC(tp, clone_out_of_proc);
257
258 return atf_no_error();
259 }
260