regress/lib/libc/clone/clonetest.c

   1 /*      $NetBSD: clonetest.c,v 1.9 2004/07/19 06:34:10 chs Exp $        */
   2
   3 /*
   4  * This file placed in the public domain.
   5  * Jason R. Thorpe, July 16, 2001.
   6  */
   7
   8 #include <sys/types.h>
   9 #include <sys/mman.h>
  10 #include <sys/wait.h>
  11 #include <sys/resource.h>
  12 #include <err.h>
  13 #include <sched.h>
  14 #include <signal.h>
  15 #include <stdio.h>
  16 #include <unistd.h>
  17 #include <stdlib.h>
  18 #include <errno.h>
  19
  20 static int      newclone(void *);
  21 static int      stackdir(void *);
  22 static void     test1(void);
  23 static void     test2(void);
  24 static void     test3(void);
  25
  26 int     main(int, char *[]);
  27
  28
  29 #define STACKSIZE       (8 * 1024)
  30
  31 #define FROBVAL         41973
  32 #define CHILDEXIT       0xa5
  33
  34 int
  35 main(int argc, char *argv[])
  36 {
  37         test1();
  38         test2();
  39         test3();
  40         return 0;
  41 }
  42
  43 static void
  44 test1()
  45 {
  46         sigset_t mask;
  47         void *allocstack, *stack;
  48         pid_t pid;
  49         volatile long frobme[2];
  50         int stat;
  51
  52         allocstack = mmap(NULL, STACKSIZE, PROT_READ|PROT_WRITE|PROT_EXEC,
  53             MAP_PRIVATE|MAP_ANON, -1, (off_t) 0);
  54
  55         if (allocstack == MAP_FAILED)
  56                 err(1, "mmap stack");
  57
  58         stack = (caddr_t) allocstack + STACKSIZE * stackdir(&stat);
  59
  60         printf("parent: stack = %p, frobme = %p\n", stack, frobme);
  61         fflush(stdout);
  62
  63         frobme[0] = (long)getpid();
  64         frobme[1] = (long)stack;
  65
  66         sigemptyset(&mask);
  67         sigaddset(&mask, SIGUSR1);
  68
  69         if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1)
  70                 err(1, "sigprocmask (SIGUSR1)");
  71
  72         switch (pid = __clone(newclone, stack,
  73             CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGUSR1,
  74             (void *)frobme)) {
  75         case 0:
  76                 errx(1, "clone returned 0");
  77                 /*NOTREACHED*/
  78         case -1:
  79                 err(1, "clone");
  80                 /*NOTREACHED*/
  81         default:
  82                 while (waitpid(pid, &stat, __WCLONE) != pid)
  83                         continue;
  84         }
  85
  86         if (WIFEXITED(stat) == 0)
  87                 errx(1, "child didn't exit");
  88
  89         printf("parent: childexit = 0x%x, frobme = %ld\n",
  90             WEXITSTATUS(stat), frobme[1]);
  91
  92         if (WEXITSTATUS(stat) != CHILDEXIT || frobme[1] != FROBVAL)
  93                 exit(1);
  94
  95         if (munmap(allocstack, STACKSIZE) == -1)
  96                 err(1, "munmap stack");
  97
  98         printf("test1: PASS\n");
  99 }
 100
 101 static void
 102 test2()
 103 {
 104         void *allocstack, *stack;
 105         int rv, stat;
 106
 107         allocstack = mmap(NULL, STACKSIZE, PROT_READ|PROT_WRITE|PROT_EXEC,
 108             MAP_PRIVATE|MAP_ANON, -1, (off_t) 0);
 109
 110         if (allocstack == MAP_FAILED)
 111                 err(1, "mmap stack");
 112
 113         stack = (caddr_t) allocstack + STACKSIZE * stackdir(&stat);
 114
 115         errno = 0;
 116         rv = __clone(0, stack,
 117             CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGCHLD, NULL);
 118         if (rv != -1 || errno != EINVAL)
 119                 errx(1, "clone did not return EINVAL on NULL function pointer: "
 120                      "rv %d errno %d", rv, errno);
 121         rv = __clone(newclone, NULL,
 122             CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGCHLD,
 123             NULL);
 124         if (rv != -1 || errno != EINVAL)
 125                 errx(1, "clone did not return EINVAL on NULL stack pointer: "
 126                      "rv %d errno %d", rv, errno);
 127
 128         if (munmap(allocstack, STACKSIZE) == -1)
 129                 err(1, "munmap stack");
 130
 131         printf("test2: PASS\n");
 132 }
 133
 134 static void
 135 test3()
 136 {
 137         struct rlimit rl;
 138
 139         /* Can't enforce resource limit on root */
 140         if (geteuid() == 0)
 141                 return;
 142
 143         if (getrlimit(RLIMIT_NPROC, &rl) == -1)
 144                 err(1, "getrlimit");
 145         rl.rlim_cur = 0;
 146         rl.rlim_max = 0;
 147         if (setrlimit(RLIMIT_NPROC, &rl) == -1)
 148                 err(1, "setrlimit");
 149         if (__clone(newclone, malloc(10240),
 150             CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGCHLD,
 151             (void *)&rl) != -1 || errno != EAGAIN)
 152                 errx(1, "clone did not return EAGAIN running out of procs");
 153
 154         printf("test3: PASS\n");
 155 }
 156
 157 static int
 158 newclone(void *arg)
 159 {
 160         long *frobp = arg, diff;
 161
 162         printf("child: stack ~= %p, frobme = %p\n", &frobp, frobp);
 163         fflush(stdout);
 164
 165         if (frobp[0] != getppid())
 166                 errx(1, "argument does not contain parent's pid");
 167
 168         if (frobp[0] == getpid())
 169                 errx(1, "called in parent's pid");
 170
 171         if (frobp[1] > (long)&frobp)
 172                 diff = frobp[1] - (long)&frobp;
 173         else
 174                 diff = (long)&frobp - frobp[1];
 175
 176         if (diff > 1024)
 177                 errx(1, "called with bad stack");
 178
 179         frobp[1] = FROBVAL;
 180
 181         return (CHILDEXIT);
 182 }
 183
 184 /*
 185  * return 1 if the stack grows down, 0 if it grows up.
 186  */
 187 static int
 188 stackdir(void *p)
 189 {
 190         int val;
 191         void *q = &val;
 192
 193         return p < q ? 0 : 1;
 194 }