[CRIU] [PATCH 9/9] zdtm: add a test to check non-root shared bind-mounts

[Andrey Vagin]

Here is an example from a fedora container:
65 64 252:0 /vz/private/1 / rw,relatime shared:29 - ext4 /dev/mapper/centos_pcs-root rw,data=ordered
77 65 252:0 /vz/private/1/var/tmp/systemd-httpd.service-XLnJPNc/tmp /var/tmp rw,relatime shared:41 - ext4 /dev/mapper/centos_pcs-root rw,data=ordered

We can see non-root shared mount, which is mounted to the root
mount from the same shared group. The test emulates this situation.

Signed-off-by: Andrey Vagin <avagin at openvz.org>
---
 test/zdtm.sh                            |   3 +
 test/zdtm/live/static/Makefile          |   1 +
 test/zdtm/live/static/mntns_root_bind.c | 106 ++++++++++++++++++++++++++++++++
 3 files changed, 110 insertions(+)
 create mode 100644 test/zdtm/live/static/mntns_root_bind.c

diff --git a/test/zdtm.sh b/test/zdtm.sh
index 9a2c188..e910621 100755
--- a/test/zdtm.sh
+++ b/test/zdtm.sh
@@ -181,6 +181,7 @@ static/cgroup01
 static/cgroup02
 ns/static/clean_mntns
 static/remap_dead_pid
+ns/static/mntns_root_bind
 "
 
 TEST_CR_KERNEL="
@@ -232,6 +233,7 @@ deleted_dev
 mntns_open
 mntns_link_remap
 mntns_link_ghost
+mntns_root_bind
 sockets00
 "
 
@@ -509,6 +511,7 @@ run_test()
 	echo "Execute $test"
 
 	start_test $tdir $tname || return 1
+	read
 
 	if [ $START_ONLY -eq 1 ]; then
 		echo "Test is started"
diff --git a/test/zdtm/live/static/Makefile b/test/zdtm/live/static/Makefile
index e9cac39..00104dd 100644
--- a/test/zdtm/live/static/Makefile
+++ b/test/zdtm/live/static/Makefile
@@ -175,6 +175,7 @@ TST_DIR		=				\
 		mntns_open			\
 		mntns_link_remap		\
 		mntns_link_ghost		\
+		mntns_root_bind			\
 
 TST_DIR_FILE	=				\
 		chroot				\
diff --git a/test/zdtm/live/static/mntns_root_bind.c b/test/zdtm/live/static/mntns_root_bind.c
new file mode 100644
index 0000000..2ab5837
--- /dev/null
+++ b/test/zdtm/live/static/mntns_root_bind.c
@@ -0,0 +1,106 @@
+#define _GNU_SOURCE
+#include <stdbool.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdio.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sched.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <limits.h>
+
+#include "zdtmtst.h"
+
+#ifndef CLONE_NEWNS
+#define CLONE_NEWNS     0x00020000
+#endif
+
+const char *test_doc	= "Check that mnt_id is repsected";
+const char *test_author	= "Pavel Emelianov <xemul at parallels.com>";
+
+char *dirname;
+TEST_OPTION(dirname, string, "directory name", 1);
+
+
+int main(int argc, char **argv)
+{
+	char path[PATH_MAX], bpath[PATH_MAX], spath[PATH_MAX];
+	pid_t pid;
+	int status;
+	task_waiter_t t;
+
+	test_init(argc, argv);
+
+	task_waiter_init(&t);
+
+	mount(NULL, "/", NULL, MS_SHARED, NULL);
+
+	snprintf(path, sizeof(path), "%s/test", dirname);
+	snprintf(bpath, sizeof(bpath), "%s/test.bind", dirname);
+	snprintf(spath, sizeof(spath), "%s/test/sub", dirname);
+	if (mkdir(dirname, 0700) ||
+	    mkdir(path, 0700) ||
+	    mkdir(spath, 0700) ||
+	    mkdir(bpath, 0700)) {
+		err("mkdir");
+		return 1;
+	}
+
+	pid = fork();
+	if (pid < 0) {
+		err("fork");
+		return 1;
+	}
+	if (pid == 0) {
+		unshare(CLONE_NEWNS);
+		if (mount(path, bpath, NULL, MS_BIND, NULL)) {
+			err("mount");
+			return 1;
+		}
+
+		task_waiter_complete(&t, 1);
+		task_waiter_wait4(&t, 2);
+
+
+		if (umount(bpath)) {
+			fail("umount");
+			return 1;
+		}
+
+		return 0;
+	}
+
+	task_waiter_wait4(&t, 1);
+
+	if (mount("test", spath, "tmpfs", 0, NULL)) {
+		err("mount");
+		return 1;
+	}
+
+
+	test_daemon();
+	test_waitsig();
+
+	if (umount(spath)) {
+		fail("umount");
+		return 1;
+	}
+	task_waiter_complete(&t, 2);
+
+	if (waitpid(pid, &status, 0) != pid) {
+		err("waitpid %d", pid);
+		return 1;
+	}
+
+	if (status) {
+		err("%d/%d/%d/%d", WIFEXITED(status), WEXITSTATUS(status), WIFSIGNALED(status), WTERMSIG(status));
+		return 1;
+	}
+
+	pass();
+
+	return 0;
+}
-- 
1.9.3