[LTP] [PATCH v5] syscalls/mount_setattr01: Add basic functional test

Chen Hanxiao
2022-04-28T10:47:06Z

The mount_setattr() system call changes the mount properties of
a mount or an entire mount tree. Here we check whether the mount
attributes are set correctly.

Signed-off-by: Dai Shili <daisl.fnst@fujitsu.com>
Signed-off-by: Chen Hanxiao <chenhx.fnst@fujitsu.com>
---
v5:
1. remove numbers from doc
2. modify cleanup labels
v4:
1) add AC_CHECK_TYPES for mount_attr
2) fix cleanup issues
v3:
1) fix doc issue
2) fix bugs according to Petr's comments
v2:
1) fix bugs according to Cyril's comments
2) just set and test mount attributes, remove attr_clr section.

configure.ac | 7 +
include/lapi/fsmount.h | 47 +++++++
runtest/syscalls | 2 +
.../kernel/syscalls/mount_setattr/.gitignore | 1 +
.../kernel/syscalls/mount_setattr/Makefile | 6 +
.../syscalls/mount_setattr/mount_setattr01.c | 132 ++++++++++++++++++
6 files changed, 195 insertions(+)
create mode 100644 testcases/kernel/syscalls/mount_setattr/.gitignore
create mode 100644 testcases/kernel/syscalls/mount_setattr/Makefile
create mode 100644 testcases/kernel/syscalls/mount_setattr/mount_setattr01.c

diff --git a/configure.ac b/configure.ac
index 81cba98c2..816ebf820 100644
--- a/configure.ac
+++ b/configure.ac
@@ -220,6 +220,13 @@ AC_CHECK_TYPES([struct __kernel_old_timeval, struct __kernel_old_timespec, struc
struct __kernel_old_itimerspec, struct __kernel_itimerspec],,,[#include <sys/socket.h>])

AC_CHECK_TYPES([struct futex_waitv],,,[#include <linux/futex.h>])
+AC_CHECK_TYPES([struct mount_attr],,,[
+#ifdef HAVE_LINUX_MOUNT_H
+# include <linux/mount.h>
+#else
+# include <sys/mount.h>
+#endif
+])

# Tools knobs

diff --git a/include/lapi/fsmount.h b/include/lapi/fsmount.h
index 377af85ec..abf059486 100644
--- a/include/lapi/fsmount.h
+++ b/include/lapi/fsmount.h
@@ -16,6 +16,44 @@
#include "lapi/fcntl.h"
#include "lapi/syscalls.h"

+/*
+ * Mount attributes.
+ */
+#ifndef MOUNT_ATTR_RDONLY
+# define MOUNT_ATTR_RDONLY 0x00000001 /* Mount read-only */
+#endif
+#ifndef MOUNT_ATTR_NOSUID
+# define MOUNT_ATTR_NOSUID 0x00000002 /* Ignore suid and sgid bits */
+#endif
+#ifndef MOUNT_ATTR_NODEV
+# define MOUNT_ATTR_NODEV 0x00000004 /* Disallow access to device special files */
+#endif
+#ifndef MOUNT_ATTR_NOEXEC
+# define MOUNT_ATTR_NOEXEC 0x00000008 /* Disallow program execution */
+#endif
+#ifndef MOUNT_ATTR_NODIRATIME
+# define MOUNT_ATTR_NODIRATIME 0x00000080 /* Do not update directory access times */
+#endif
+#ifndef MOUNT_ATTR_NOSYMFOLLOW
+# define MOUNT_ATTR_NOSYMFOLLOW 0x00200000 /* Do not follow symlinks */
+#endif
+
+#ifndef ST_NOSYMFOLLOW
+# define ST_NOSYMFOLLOW 0x2000 /* do not follow symlinks */
+#endif
+
+#ifndef HAVE_STRUCT_MOUNT_ATTR
+/*
+ * mount_setattr()
+ */
+struct mount_attr {
+ uint64_t attr_set;
+ uint64_t attr_clr;
+ uint64_t propagation;
+ uint64_t userns_fd;
+};
+#endif
+
#ifndef HAVE_FSOPEN
static inline int fsopen(const char *fsname, unsigned int flags)
{
@@ -62,6 +100,15 @@ static inline int open_tree(int dirfd, const char *pathname, unsigned int flags)
}
#endif /* HAVE_OPEN_TREE */

+#ifndef HAVE_MOUNT_SETATTR
+static inline int mount_setattr(int dirfd, const char *from_pathname, unsigned int flags,
+ struct mount_attr *attr, size_t size)
+{
+ return tst_syscall(__NR_mount_setattr, dirfd, from_pathname, flags,
+ attr, size);
+}
+#endif /* HAVE_MOUNT_SETATTR */
+
/*
* New headers added in kernel after 5.2 release, create them for old userspace.
*/
diff --git a/runtest/syscalls b/runtest/syscalls
index 24d0f955d..3b26d19e6 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -803,6 +803,8 @@ mount04 mount04
mount05 mount05
mount06 mount06

+mount_setattr01 mount_setattr01
+
move_mount01 move_mount01
move_mount02 move_mount02

diff --git a/testcases/kernel/syscalls/mount_setattr/.gitignore b/testcases/kernel/syscalls/mount_setattr/.gitignore
new file mode 100644
index 000000000..52a77b9ca
--- /dev/null
+++ b/testcases/kernel/syscalls/mount_setattr/.gitignore
@@ -0,0 +1 @@
+/mount_setattr01
diff --git a/testcases/kernel/syscalls/mount_setattr/Makefile b/testcases/kernel/syscalls/mount_setattr/Makefile
new file mode 100644
index 000000000..5ea7d67db
--- /dev/null
+++ b/testcases/kernel/syscalls/mount_setattr/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+top_srcdir ?= ../../../..
+
+include $(top_srcdir)/include/mk/testcases.mk
+include $(top_srcdir)/include/mk/generic_leaf_target.mk
diff --git a/testcases/kernel/syscalls/mount_setattr/mount_setattr01.c b/testcases/kernel/syscalls/mount_setattr/mount_setattr01.c
new file mode 100644
index 000000000..ef26bcbf2
--- /dev/null
+++ b/testcases/kernel/syscalls/mount_setattr/mount_setattr01.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022 FUJITSU LIMITED. All rights reserved.
+ * Author: Dai Shili <daisl.fnst@fujitsu.com>
+ * Author: Chen Hanxiao <chenhx.fnst@fujitsu.com>
+ */
+
+/*\
+ * [Description]
+ *
+ * Basic mount_setattr() test.
+ * Test whether the basic mount attributes are set correctly.
+ *
+ * Verify some MOUNT_SETATTR(2) attributes:
+ *
+ * - MOUNT_ATTR_RDONLY - makes the mount read-only
+ * - MOUNT_ATTR_NOSUID - causes the mount not to honor the
+ * set-user-ID and set-group-ID mode bits and file capabilities
+ * when executing programs.
+ * - MOUNT_ATTR_NODEV - prevents access to devices on this mount
+ * - MOUNT_ATTR_NOEXEC - prevents executing programs on this mount
+ * - MOUNT_ATTR_NOSYMFOLLOW - prevents following symbolic links
+ * on this mount
+ * - MOUNT_ATTR_NODIRATIME - prevents updating access time for
+ * directories on this mount
+ *
+ * The functionality was added in v5.12.
+ */
+
+#define _GNU_SOURCE
+
+#include <sys/statvfs.h>
+#include "tst_test.h"
+#include "lapi/fsmount.h"
+#include "lapi/stat.h"
+
+#define MNTPOINT "mntpoint"
+#define OT_MNTPOINT "ot_mntpoint"
+#define TCASE_ENTRY(attrs, exp_attrs) \
+ { \
+ .name = #attrs, \
+ .mount_attrs = attrs, \
+ .expect_attrs = exp_attrs \
+ }
+
+static int mount_flag, otfd = -1;
+
+static struct tcase {
+ char *name;
+ unsigned int mount_attrs;
+ unsigned int expect_attrs;
+} tcases[] = {
+ TCASE_ENTRY(MOUNT_ATTR_RDONLY, ST_RDONLY),
+ TCASE_ENTRY(MOUNT_ATTR_NOSUID, ST_NOSUID),
+ TCASE_ENTRY(MOUNT_ATTR_NODEV, ST_NODEV),
+ TCASE_ENTRY(MOUNT_ATTR_NOEXEC, ST_NOEXEC),
+ TCASE_ENTRY(MOUNT_ATTR_NOSYMFOLLOW, ST_NOSYMFOLLOW),
+ TCASE_ENTRY(MOUNT_ATTR_NODIRATIME, ST_NODIRATIME),
+};
+
+static void cleanup(void)
+{
+ if (otfd > -1)
+ SAFE_CLOSE(otfd);
+ if (mount_flag)
+ SAFE_UMOUNT(OT_MNTPOINT);
+}
+
+static void setup(void)
+{
+ fsopen_supported_by_kernel();
+ struct stat st = {0};
+
+ if (stat(OT_MNTPOINT, &st) == -1)
+ SAFE_MKDIR(OT_MNTPOINT, 0777);
+}
+
+static void run(unsigned int n)
+{
+ struct tcase *tc = &tcases[n];
+ struct mount_attr attr = {
+ .attr_set = tc->mount_attrs,
+ };
+ struct statvfs buf;
+
+ TST_EXP_FD_SILENT(open_tree(AT_FDCWD, MNTPOINT, AT_EMPTY_PATH |
+ AT_SYMLINK_NOFOLLOW | OPEN_TREE_CLOEXEC | OPEN_TREE_CLONE));
+ if (!TST_PASS)
+ return;
+
+ otfd = (int)TST_RET;
+
+ TST_EXP_PASS_SILENT(mount_setattr(otfd, "", AT_EMPTY_PATH, &attr, sizeof(attr)),
+ "%s set", tc->name);
+ if (!TST_PASS)
+ goto out1;
+
+ TST_EXP_PASS_SILENT(move_mount(otfd, "", AT_FDCWD, OT_MNTPOINT, MOVE_MOUNT_F_EMPTY_PATH));
+ if (!TST_PASS)
+ goto out1;
+ mount_flag = 1;
+ SAFE_CLOSE(otfd);
+
+ TST_EXP_PASS_SILENT(statvfs(OT_MNTPOINT, &buf), "statvfs sucess");
+ if (!TST_PASS)
+ goto out2;
+
+ if (buf.f_flag & tc->expect_attrs)
+ tst_res(TPASS, "%s is actually set as expected", tc->name);
+ else
+ tst_res(TFAIL, "%s is not actually set as expected", tc->name);
+
+ goto out2;
+
+out1:
+ SAFE_CLOSE(otfd);
+out2:
+ mount_flag = 0;
+ SAFE_UMOUNT(OT_MNTPOINT);
+}
+
+static struct tst_test test = {
+ .tcnt = ARRAY_SIZE(tcases),
+ .test = run,
+ .setup = setup,
+ .cleanup = cleanup,
+ .needs_root = 1,
+ .mount_device = 1,
+ .mntpoint = MNTPOINT,
+ .all_filesystems = 1,
+ .skip_filesystems = (const char *const []){"fuse", NULL},
+};
--
2.35.1