glibc/sysdeps/unix/sysv/linux/tst-ttyname-namespace.c

148 lines
4.2 KiB
C

/* Tests for ttyname/ttyname_r with namespaces.
Copyright (C) 2017-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, see <https://www.gnu.org/licenses/>. */
#include <sched.h>
#include <sys/prctl.h>
#include <sys/wait.h>
#include <support/namespace.h>
#include "tst-ttyname-common.c"
static int
do_in_chroot_2 (int (*cb)(const char *, int))
{
printf ("info: entering chroot 2\n");
int pid_pipe[2];
xpipe (pid_pipe);
int exit_pipe[2];
xpipe (exit_pipe);
/* Open the PTS that we'll be testing on. */
int master;
char *slavename;
VERIFY ((master = posix_openpt (O_RDWR|O_NOCTTY|O_NONBLOCK)) >= 0);
VERIFY ((slavename = ptsname (master)));
VERIFY (unlockpt (master) == 0);
if (strncmp (slavename, "/dev/pts/", 9) != 0)
FAIL_UNSUPPORTED ("slave pseudo-terminal is not under /dev/pts/: %s",
slavename);
adjust_file_limit (slavename);
/* wait until in a new mount ns to open the slave */
/* enable `wait`ing on grandchildren */
VERIFY (prctl (PR_SET_CHILD_SUBREAPER, 1) == 0);
pid_t pid = xfork (); /* outer child */
if (pid == 0)
{
xclose (master);
xclose (pid_pipe[0]);
xclose (exit_pipe[1]);
if (!support_enter_mount_namespace ())
FAIL_UNSUPPORTED ("could not enter new mount namespace");
int slave = xopen (slavename, O_RDWR, 0);
if (!doit (slave, "basic smoketest",
(struct result_r){.name=slavename, .ret=0, .err=0}))
_exit (1);
VERIFY (mount ("tmpfs", chrootdir, "tmpfs", 0, "mode=755") == 0);
VERIFY (chdir (chrootdir) == 0);
xmkdir ("proc", 0755);
xmkdir ("dev", 0755);
xmkdir ("dev/pts", 0755);
VERIFY (mount ("devpts", "dev/pts", "devpts",
MS_NOSUID|MS_NOEXEC,
"newinstance,ptmxmode=0666,mode=620") == 0);
VERIFY (symlink ("pts/ptmx", "dev/ptmx") == 0);
touch ("console", 0);
touch ("dev/console", 0);
VERIFY (mount (slavename, "console", NULL, MS_BIND, NULL) == 0);
xchroot (".");
if (unshare (CLONE_NEWNS | CLONE_NEWPID) < 0)
FAIL_UNSUPPORTED ("could not enter new PID namespace");
pid = xfork (); /* inner child */
if (pid == 0)
{
xclose (pid_pipe[1]);
/* wait until the outer child has exited */
char c;
VERIFY (read (exit_pipe[0], &c, 1) == 0);
xclose (exit_pipe[0]);
if (mount ("proc", "/proc", "proc",
MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL) != 0)
{
/* This happens if we're trying to create a nested container,
like if the build is running under podman, and we lack
priviledges. */
if (errno == EPERM)
_exit (EXIT_UNSUPPORTED);
else
_exit (EXIT_FAILURE);
}
char *linkname = xasprintf ("/proc/self/fd/%d", slave);
char *target = proc_fd_readlink (linkname);
VERIFY (strcmp (target, strrchr (slavename, '/')) == 0);
free (linkname);
_exit (cb (slavename, slave));
}
int status;
xwaitpid (pid, &status, 0);
_exit (WEXITSTATUS (status));
}
xclose (pid_pipe[1]);
xclose (exit_pipe[0]);
xclose (exit_pipe[1]);
/* wait for the outer child */
int status;
xwaitpid (pid, &status, 0);
VERIFY (WIFEXITED (status));
int ret = WEXITSTATUS (status);
if (ret != 0)
FAIL_UNSUPPORTED ("unable to mount /proc on inner child process");
xclose (pid_pipe[0]);
return 0;
}
static int
do_test (void)
{
support_become_root ();
do_in_chroot_2 (run_chroot_tests);
return 0;
}
#include <support/test-driver.c>