/* Execute LINE as a shell command, returning its status.  */
static int
do_system (const char *line)
{
  int status, save;
  pid_t pid;
  struct sigaction sa;
#ifndef _LIBC_REENTRANT
  struct sigaction intr, quit;
#endif
  sigset_t omask;

  sa.sa_handler = SIG_IGN;
  sa.sa_flags = 0;
  __sigemptyset (&sa.sa_mask);

  DO_LOCK ();
  if (ADD_REF () == 0)
    {
      if (__sigaction (SIGINT, &sa, &intr) < 0)
	{
	  SUB_REF ();
	  goto out;
	}
      if (__sigaction (SIGQUIT, &sa, &quit) < 0)
	{
	  save = errno;
	  SUB_REF ();
	  goto out_restore_sigint;
	}
    }
  DO_UNLOCK ();

  /* We reuse the bitmap in the 'sa' structure.  */
  __sigaddset (&sa.sa_mask, SIGCHLD);
  save = errno;
  if (__sigprocmask (SIG_BLOCK, &sa.sa_mask, &omask) < 0)
    {
#ifndef _LIBC
      if (errno == ENOSYS)
	__set_errno (save);
      else
#endif
	{
	  DO_LOCK ();
	  if (SUB_REF () == 0)
	    {
	      save = errno;
	      (void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL);
	    out_restore_sigint:
	      (void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
	      __set_errno (save);
	    }
	out:
	  DO_UNLOCK ();
	  return -1;
	}
    }

#ifdef CLEANUP_HANDLER
  CLEANUP_HANDLER;
#endif

#ifdef FORK
  pid = FORK ();
#else
  pid = __fork ();
#endif
  if (pid == (pid_t) 0)
    {
      /* Child side.  */
      const char *new_argv[4];
      new_argv[0] = SHELL_NAME;
      new_argv[1] = "-c";
      new_argv[2] = line;
      new_argv[3] = NULL;

      /* Restore the signals.  */
      (void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
      (void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL);
      (void) __sigprocmask (SIG_SETMASK, &omask, (sigset_t *) NULL);
      INIT_LOCK ();

      /* Exec the shell.  */
      (void) __execve (SHELL_PATH, (char *const *) new_argv, __environ);
      _exit (127);
    }
  else if (pid < (pid_t) 0)
    /* The fork failed.  */
    status = -1;
  else
    /* Parent side.  */
    {
      /* Note the system() is a cancellation point.  But since we call
	 waitpid() which itself is a cancellation point we do not
	 have to do anything here.  */
      if (TEMP_FAILURE_RETRY (__waitpid (pid, &status, 0)) != pid)
	status = -1;
    }

#ifdef CLEANUP_HANDLER
  CLEANUP_RESET;
#endif

  save = errno;
  DO_LOCK ();
  if ((SUB_REF () == 0
       && (__sigaction (SIGINT, &intr, (struct sigaction *) NULL)
	   | __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL)) != 0)
      || __sigprocmask (SIG_SETMASK, &omask, (sigset_t *) NULL) != 0)
    {
#ifndef _LIBC
      /* glibc cannot be used on systems without waitpid.  */
      if (errno == ENOSYS)
	__set_errno (save);
      else
#endif
	status = -1;
    }
  DO_UNLOCK ();

  return status;
}
示例#2
0
int kernel_execve(const char *filename, char *const argv[], char *const envp[])
{
	return __execve(filename, argv, envp, current);
}
示例#3
0
文件: execv.c 项目: AubrCool/glibc
/* Execute PATH with arguments ARGV and environment from `environ'.  */
int
execv (const char *path, char *const argv[])
{
  return __execve (path, argv, __environ);
}
示例#4
0
文件: hooks.c 项目: krichter722/gfarm
int
_private_execve(const char *filename, char *const argv [], char *const envp[])
{
	_gfs_hook_debug_v(fputs("Hooking execve\n", stderr));
	return (__execve(filename, argv, envp));
}
示例#5
0
文件: spawni.c 项目: siddhesh/glibc
/* Spawn a new process executing PATH with the attributes describes in *ATTRP.
   Before running the process perform the actions described in FILE-ACTIONS. */
int
__spawni (pid_t *pid, const char *file,
	  const posix_spawn_file_actions_t *file_actions,
	  const posix_spawnattr_t *attrp, char *const argv[],
	  char *const envp[], int xflags)
{
  pid_t new_pid;
  char *path, *p, *name;
  size_t len;
  size_t pathlen;

  /* Do this once.  */
  short int flags = attrp == NULL ? 0 : attrp->__flags;

  /* Generate the new process.  */
  if ((flags & POSIX_SPAWN_USEVFORK) != 0
      /* If no major work is done, allow using vfork.  Note that we
	 might perform the path searching.  But this would be done by
	 a call to execvp(), too, and such a call must be OK according
	 to POSIX.  */
      || ((flags & (POSIX_SPAWN_SETSIGMASK | POSIX_SPAWN_SETSIGDEF
		    | POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER
		    | POSIX_SPAWN_SETPGROUP | POSIX_SPAWN_RESETIDS)) == 0
	  && file_actions == NULL))
    new_pid = __vfork ();
  else
    new_pid = __fork ();

  if (new_pid != 0)
    {
      if (new_pid < 0)
	return errno;

      /* The call was successful.  Store the PID if necessary.  */
      if (pid != NULL)
	*pid = new_pid;

      return 0;
    }

  /* Set signal mask.  */
  if ((flags & POSIX_SPAWN_SETSIGMASK) != 0
      && __sigprocmask (SIG_SETMASK, &attrp->__ss, NULL) != 0)
    _exit (SPAWN_ERROR);

  /* Set signal default action.  */
  if ((flags & POSIX_SPAWN_SETSIGDEF) != 0)
    {
      /* We have to iterate over all signals.  This could possibly be
	 done better but it requires system specific solutions since
	 the sigset_t data type can be very different on different
	 architectures.  */
      int sig;
      struct sigaction sa;

      memset (&sa, '\0', sizeof (sa));
      sa.sa_handler = SIG_DFL;

      for (sig = 1; sig <= _NSIG; ++sig)
	if (__sigismember (&attrp->__sd, sig) != 0
	    && __sigaction (sig, &sa, NULL) != 0)
	  _exit (SPAWN_ERROR);

    }

#ifdef _POSIX_PRIORITY_SCHEDULING
  /* Set the scheduling algorithm and parameters.  */
  if ((flags & (POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER))
      == POSIX_SPAWN_SETSCHEDPARAM)
    {
      if (__sched_setparam (0, &attrp->__sp) == -1)
	_exit (SPAWN_ERROR);
    }
  else if ((flags & POSIX_SPAWN_SETSCHEDULER) != 0)
    {
      if (__sched_setscheduler (0, attrp->__policy, &attrp->__sp) == -1)
	_exit (SPAWN_ERROR);
    }
#endif

  /* Set the process group ID.  */
  if ((flags & POSIX_SPAWN_SETPGROUP) != 0
      && __setpgid (0, attrp->__pgrp) != 0)
    _exit (SPAWN_ERROR);

  /* Set the effective user and group IDs.  */
  if ((flags & POSIX_SPAWN_RESETIDS) != 0
      && (local_seteuid (__getuid ()) != 0
	  || local_setegid (__getgid ()) != 0))
    _exit (SPAWN_ERROR);

  /* Execute the file actions.  */
  if (file_actions != NULL)
    {
      int cnt;
      struct rlimit64 fdlimit;
      bool have_fdlimit = false;

      for (cnt = 0; cnt < file_actions->__used; ++cnt)
	{
	  struct __spawn_action *action = &file_actions->__actions[cnt];

	  switch (action->tag)
	    {
	    case spawn_do_close:
	      if (close_not_cancel (action->action.close_action.fd) != 0)
		{
		  if (! have_fdlimit)
		    {
		      __getrlimit64 (RLIMIT_NOFILE, &fdlimit);
		      have_fdlimit = true;
		    }

		  /* Only signal errors for file descriptors out of range.  */
		  if (action->action.close_action.fd < 0
		      || action->action.close_action.fd >= fdlimit.rlim_cur)
		    /* Signal the error.  */
		    _exit (SPAWN_ERROR);
		}
	      break;

	    case spawn_do_open:
	      {
		int new_fd = open_not_cancel (action->action.open_action.path,
					      action->action.open_action.oflag
					      | O_LARGEFILE,
					      action->action.open_action.mode);

		if (new_fd == -1)
		  /* The `open' call failed.  */
		  _exit (SPAWN_ERROR);

		/* Make sure the desired file descriptor is used.  */
		if (new_fd != action->action.open_action.fd)
		  {
		    if (__dup2 (new_fd, action->action.open_action.fd)
			!= action->action.open_action.fd)
		      /* The `dup2' call failed.  */
		      _exit (SPAWN_ERROR);

		    if (close_not_cancel (new_fd) != 0)
		      /* The `close' call failed.  */
		      _exit (SPAWN_ERROR);
		  }
	      }
	      break;

	    case spawn_do_dup2:
	      if (__dup2 (action->action.dup2_action.fd,
			  action->action.dup2_action.newfd)
		  != action->action.dup2_action.newfd)
		/* The `dup2' call failed.  */
		_exit (SPAWN_ERROR);
	      break;
	    }
	}
    }

  if ((xflags & SPAWN_XFLAGS_USE_PATH) == 0 || strchr (file, '/') != NULL)
    {
      /* The FILE parameter is actually a path.  */
      __execve (file, argv, envp);

      maybe_script_execute (file, argv, envp, xflags);

      /* Oh, oh.  `execve' returns.  This is bad.  */
      _exit (SPAWN_ERROR);
    }

  /* We have to search for FILE on the path.  */
  path = getenv ("PATH");
  if (path == NULL)
    {
      /* There is no `PATH' in the environment.
	 The default search path is the current directory
	 followed by the path `confstr' returns for `_CS_PATH'.  */
      len = confstr (_CS_PATH, (char *) NULL, 0);
      path = (char *) __alloca (1 + len);
      path[0] = ':';
      (void) confstr (_CS_PATH, path + 1, len);
    }

  len = strlen (file) + 1;
  pathlen = strlen (path);
  name = __alloca (pathlen + len + 1);
  /* Copy the file name at the top.  */
  name = (char *) memcpy (name + pathlen + 1, file, len);
  /* And add the slash.  */
  *--name = '/';

  p = path;
  do
    {
      char *startp;

      path = p;
      p = __strchrnul (path, ':');

      if (p == path)
	/* Two adjacent colons, or a colon at the beginning or the end
	   of `PATH' means to search the current directory.  */
	startp = name + 1;
      else
	startp = (char *) memcpy (name - (p - path), path, p - path);

      /* Try to execute this name.  If it works, execv will not return.  */
      __execve (startp, argv, envp);

      maybe_script_execute (startp, argv, envp, xflags);

      switch (errno)
	{
	case EACCES:
	case ENOENT:
	case ESTALE:
	case ENOTDIR:
	  /* Those errors indicate the file is missing or not executable
	     by us, in which case we want to just try the next path
	     directory.  */
	  break;

	default:
	  /* Some other error means we found an executable file, but
	     something went wrong executing it; return the error to our
	     caller.  */
	  _exit (SPAWN_ERROR);
	    }
    }
  while (*p++ != '\0');

  /* Return with an error.  */
  _exit (SPAWN_ERROR);
}