The new mount API was added on Linux 5.2 with six new syscalls:
fsopen, fsconfig, fsmount, move_mount, fspick, and open_tree.
The new test is far from extensive and only check for error path
and minimal funcionality to see if arguments are issued correctly.
Checked on x86_64-linux-gnu.
---
sysdeps/unix/sysv/linux/Makefile | 1 +
sysdeps/unix/sysv/linux/tst-mount.c | 95 +++++++++++++++++++++++++++++
2 files changed, 96 insertions(+)
create mode 100644 sysdeps/unix/sysv/linux/tst-mount.c
@@ -129,6 +129,7 @@ tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \
tst-epoll \
tst-pidfd \
tst-process_mrelease \
+ tst-mount \
# tests
# process_madvise requires CAP_SYS_ADMIN.
new file mode 100644
@@ -0,0 +1,95 @@
+/* Basic tests for the new Linux API added on Linux 5.2.
+ Copyright (C) 2022 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 <errno.h>
+#include <support/check.h>
+#include <support/xunistd.h>
+#include <support/namespace.h>
+#include <sys/wait.h>
+#include <sys/mount.h>
+
+static void
+subprocess (void)
+{
+ int r = fsopen ("it_should_be_not_a_valid_mount", 0);
+ TEST_VERIFY_EXIT (r == -1);
+ if (errno == ENOSYS)
+ FAIL_UNSUPPORTED ("kernel does not support new mount API, skipping test");
+ TEST_COMPARE (errno, ENODEV);
+
+ int fd = fsopen ("tmpfs", FSOPEN_CLOEXEC);
+ TEST_VERIFY (fd != -1);
+
+ TEST_COMPARE (fsconfig (-1, FSCONFIG_SET_STRING, "size", "2048", 0), -1);
+ TEST_COMPARE (errno, EINVAL);
+
+ {
+ int r = fsconfig (fd, FSCONFIG_SET_STRING, "size", "2048", 0);
+ TEST_VERIFY (r != -1);
+ r = fsconfig (fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0);
+ TEST_VERIFY (r != -1);
+ }
+
+ TEST_COMPARE (fsmount (-1, FSMOUNT_CLOEXEC, MOUNT_ATTR_NODEV), -1);
+ TEST_COMPARE (errno, EBADF);
+
+ int mfd = fsmount (fd, FSMOUNT_CLOEXEC, MOUNT_ATTR_NODEV);
+ TEST_VERIFY (mfd != -1);
+
+ TEST_COMPARE (move_mount (-1, "", AT_FDCWD, "/tmp", 0), -1);
+ TEST_COMPARE (errno, ENOENT);
+ {
+ int r = move_mount (mfd, "", AT_FDCWD, "/tmp", MOVE_MOUNT_F_EMPTY_PATH);
+ TEST_VERIFY (r != -1);
+ }
+
+ TEST_COMPARE (fspick (AT_FDCWD, "", 0), -1);
+ TEST_COMPARE (errno, ENOENT);
+ {
+ int pfd = fspick (AT_FDCWD, "/tmp", FSPICK_CLOEXEC);
+ TEST_VERIFY (pfd != -1);
+ }
+
+ TEST_COMPARE (open_tree (AT_FDCWD, "", 0), -1);
+ TEST_COMPARE (errno, ENOENT);
+ {
+ int fd_tree = open_tree (AT_FDCWD, "/tmp",
+ OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+ TEST_VERIFY (fd_tree != -1);
+ }
+
+ _exit (0);
+}
+
+static int
+do_test (void)
+{
+ support_become_root ();
+
+ pid_t pid = xfork ();
+ if (pid == 0)
+ subprocess ();
+
+ int status;
+ xwaitpid (pid, &status, 0);
+ TEST_VERIFY (WIFEXITED (status));
+
+ return 0;
+}
+
+#include <support/test-driver.c>