zdtm: Check a private mount in a shared mount

Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

test/zdtm/static/Makefile

@@ -225,6 +225,7 @@ TST_DIR		=				\
 		mntns_shared_bind02		\
 		mntns_root_bind			\
 		mntns_root_bind02		\
+		mntns_shared_vs_private		\
 		mnt_ext_auto			\
 		mnt_ext_master			\
 		mntns_deleted			\

test/zdtm/static/mntns_shared_vs_private.c

@@ -0,0 +1,118 @@
+#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 a private mount in a shared mount";
+const char *test_author	= "Andrew Vagin <avagin@gmail.com>";
+
+char *dirname;
+TEST_OPTION(dirname, string, "directory name", 1);
+
+
+int main(int argc, char **argv)
+{
+	char path[PATH_MAX];
+	pid_t pid;
+	int status, i;
+	task_waiter_t t;
+
+	test_init(argc, argv);
+
+	task_waiter_init(&t);
+
+	snprintf(path, sizeof(path), "%s/fs", dirname);
+	if (mkdir(dirname, 0700)) {
+		pr_perror("mkdir");
+		return 1;
+	}
+
+	if (mount(NULL, "/", NULL, MS_SHARED, NULL)) {
+		pr_perror("mount");
+		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;
+	}
+
+	if (mkdir(path, 0700)) {
+		pr_perror("mkdir");
+		return 1;
+	}
+
+	if (mount("zdtm_fs", path, "tmpfs", 0, NULL)) {
+		pr_perror("mount");
+		return 1;
+	}
+
+	for (i = 0; i < 2; i++) {
+		pid = fork();
+		if (pid < 0) {
+			pr_perror("fork");
+			return 1;
+		}
+		if (pid == 0) {
+			unshare(CLONE_NEWNS);
+
+			task_waiter_complete(&t, 1);
+			task_waiter_wait4(&t, 2);
+
+			return 0;
+		}
+	}
+
+	for (i = 0; i < 2; i++)
+		task_waiter_wait4(&t, 1);
+
+	test_daemon();
+	test_waitsig();
+
+	if (umount(path)) {
+		pr_perror("Unable to umount %s\n", path);
+		return 1;
+	}
+	if (umount(dirname)) {
+		pr_perror("Unable to umount %s\n", dirname);
+		return 1;
+	}
+
+	for (i = 0; i < 2; i++) {
+		task_waiter_complete(&t, 2);
+
+		if (waitpid(-1, &status, 0) < 0) {
+			pr_perror("waitpid %d", pid);
+			return 1;
+		}
+
+		if (status) {
+			pr_perror("%d/%d/%d/%d", WIFEXITED(status), WEXITSTATUS(status), WIFSIGNALED(status), WTERMSIG(status));
+			return 1;
+		}
+	}
+
+	pass();
+
+	return 0;
+}

test/zdtm/static/mntns_shared_vs_private.desc

@@ -0,0 +1 @@
+{'flavor': 'ns uns', 'flags': 'suid', 'feature': 'mnt_id'}