zdtm: check children of shared slaves restore

495 494 0:62 / /zdtm/static/shared_slave_mount_children.test/share rw,relatime shared:235 - tmpfs share rw
496 494 0:62 / /zdtm/static/shared_slave_mount_children.test/slave1 rw,relatime shared:236 master:235 - tmpfs share rw
497 494 0:62 / /zdtm/static/shared_slave_mount_children.test/slave2 rw,relatime shared:236 master:235 - tmpfs share rw
498 496 0:63 / /zdtm/static/shared_slave_mount_children.test/slave1/child rw,relatime shared:237 - tmpfs child rw
499 497 0:63 / /zdtm/static/shared_slave_mount_children.test/slave2/child rw,relatime shared:237 - tmpfs child rw

Before the fix we had:

(00.167574)      1: Error (criu/mount.c:1769): mnt: A few mount points can't be mounted
(00.167577)      1: Error (criu/mount.c:1773): mnt: 498:496 / /tmp/.criu.mntns.o2Op5j/9-0000000000/zdtm/static/shared_slave_mount_children.test/slave1/child child
(00.167580)      1: Error (criu/mount.c:1773): mnt: 497:494 / /tmp/.criu.mntns.o2Op5j/9-0000000000/zdtm/static/shared_slave_mount_children.test/slave2 share
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>

test/zdtm/static/Makefile

@@ -337,6 +337,7 @@ TST_DIR		=				\
 		sk-unix-mntns			\
 		sk-unix01			\
 		unsupported_children_collision  \
+		shared_slave_mount_children	\
 
 TST_DIR_FILE	=				\
 		chroot				\

test/zdtm/static/shared_slave_mount_children.c

+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <limits.h>
+
+#include "zdtmtst.h"
+
+const char *test_doc	= "Check non-uniform shares restore fine";
+const char *test_author	= "Pavel Tikhomirov <ptikhomirov@virtuozzo.com>";
+
+char *dirname;
+TEST_OPTION(dirname, string, "directory name", 1);
+
+int main(int argc, char **argv)
+{
+	char share[PATH_MAX], slave1[PATH_MAX], slave2[PATH_MAX];
+	char child[PATH_MAX];
+
+	test_init(argc, argv);
+
+	if (mkdir(dirname, 0700)) {
+		pr_perror("mkdir");
+		return 1;
+	}
+
+	if (mount("zdtm_fs", dirname, "tmpfs", 0, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	if (mount(NULL, dirname, NULL, MS_PRIVATE, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	snprintf(share, sizeof(share), "%s/share", dirname);
+	if (mkdir(share, 0700)) {
+		pr_perror("mkdir");
+		return 1;
+	}
+
+	if (mount("share", share, "tmpfs", 0, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	if (mount(NULL, share, NULL, MS_SHARED, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	snprintf(slave1, sizeof(slave1), "%s/slave1", dirname);
+	if (mkdir(slave1, 0700)) {
+		pr_perror("mkdir");
+		return 1;
+	}
+
+	if (mount(share, slave1, NULL, MS_BIND, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	if (mount(NULL, slave1, NULL, MS_SLAVE, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	if (mount(NULL, slave1, NULL, MS_SHARED, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	snprintf(slave2, sizeof(slave2), "%s/slave2", dirname);
+	if (mkdir(slave2, 0700)) {
+		pr_perror("mkdir");
+		return 1;
+	}
+
+	if (mount(slave1, slave2, NULL, MS_BIND, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	snprintf(child, sizeof(child), "%s/slave1/child", dirname);
+	if (mkdir(child, 0700)) {
+		pr_perror("mkdir");
+		return 1;
+	}
+
+	if (mount("child", child, "tmpfs", 0, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	test_daemon();
+	test_waitsig();
+
+	if (umount(child)) {
+		pr_perror("Unable to umount %s", child);
+		return 1;
+	}
+
+	if (umount(slave2)) {
+		pr_perror("Unable to umount %s", slave2);
+		return 1;
+	}
+
+	if (umount(slave1)) {
+		pr_perror("Unable to umount %s", slave1);
+		return 1;
+	}
+
+	if (umount(share)) {
+		pr_perror("Unable to umount %s", share);
+		return 1;
+	}
+
+	if (umount(dirname)) {
+		pr_perror("Unable to umount %s", dirname);
+		return 1;
+	}
+
+	pass();
+
+	return 0;
+}

test/zdtm/static/shared_slave_mount_children.desc

+{'flavor': 'ns uns', 'flags': 'suid'}