zdtm: check link-remap and ghost files from a few mntns (v2)

v2: change an author field in a test
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

test/zdtm.sh

@@ -175,6 +175,8 @@ static/cgroup00
 static/cgroup01
 ns/static/clean_mntns
 ns/static/mntns_open
+ns/static/mntns_link_remap
+ns/static/mntns_link_ghost
 "
 
 TEST_CR_KERNEL="
@@ -209,6 +211,8 @@ cgroup01
 clean_mntns
 deleted_dev
 mntns_open
+mntns_link_remap
+mntns_link_ghost
 "
 
 source $(readlink -f `dirname $0`/env.sh) || exit 1

test/zdtm/live/static/Makefile

@@ -165,6 +165,8 @@ TST_DIR		=				\
 		rmdir_open			\
 		cgroup01			\
 		mntns_open			\
+		mntns_link_remap		\
+		mntns_link_ghost		\
 
 TST_DIR_FILE	=				\
 		chroot				\
@@ -279,6 +281,7 @@ socket-tcpbuf-local: override CFLAGS += -D ZDTM_TCP_LOCAL
 socket_listen6: override CFLAGS += -D ZDTM_IPV6
 sigpending:		override LDLIBS += -lrt
 vdso01:			override LDLIBS += -lrt
+mntns_link_remap:	override CFLAGS += -DZDTM_LINK_REMAP
 
 $(LIB):	force
 	$(Q) $(MAKE) -C $(LIBDIR)

test/zdtm/live/static/mntns_link_ghost.c

+mntns_link_remap.c
\ No newline at end of file

test/zdtm/live/static/mntns_link_remap.c

+#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 <sys/mount.h>
+
+#include "zdtmtst.h"
+
+#ifndef CLONE_NEWNS
+#define CLONE_NEWNS     0x00020000
+#endif
+
+const char *test_doc	= "Check ghost and link-remap files in a few mntns";
+const char *test_author	= "Andrew Vagin <avagin@parallels.com>";
+
+#define MPTS_FILE	"F"
+char *dirname;
+TEST_OPTION(dirname, string, "directory name", 1);
+
+#define NS_STACK_SIZE	4096
+/* All arguments should be above stack, because it grows down */
+struct ns_exec_args {
+	char stack[NS_STACK_SIZE];
+	char stack_ptr[0];
+	int fd;
+	int sync;
+};
+
+#define AWK_OK		13
+#define AWK_FAIL	42
+
+static int get_mntid(int fd)
+{
+	char str[256];
+	int mnt_id = -1;
+	FILE *f;
+
+	snprintf(str, sizeof(str), "/proc/self/fdinfo/%d", fd);
+	f = fopen(str, "r");
+	if (!f) {
+		err("Can't open %s to parse", str);
+		return -1;
+	}
+	while (fgets(str, sizeof(str), f)) {
+		if (sscanf(str, "mnt_id: %d", &mnt_id) == 1)
+			break;
+	}
+
+	fclose(f);
+	return mnt_id;
+}
+
+int ns_child(void *_arg)
+{
+	struct ns_exec_args *args = _arg;
+	int fd2;
+	int id1, id2;
+	struct stat st1, st2;
+	char lpath[PATH_MAX], fpath[PATH_MAX];
+
+	snprintf(fpath, sizeof(fpath), "%s/1", dirname);
+	if (umount(fpath)) {
+		err("umount");
+		return 1;
+	}
+
+	snprintf(lpath, sizeof(lpath), "%s/0/2", dirname);
+	snprintf(fpath, sizeof(fpath), "%s/2", dirname);
+
+	if (mkdir(fpath, 0600) < 0) {
+		fail("Can't make zdtm_sys");
+		return 1;
+	}
+
+	if (mount(lpath, fpath, NULL, MS_BIND, NULL)) {
+		err("mount");
+		return 1;
+	}
+
+	snprintf(fpath, sizeof(fpath), "%s/0", dirname);
+	if (umount(fpath)) {
+		err("umount");
+		return 1;
+	}
+
+	snprintf(fpath, sizeof(fpath), "%s/2/%s", dirname, MPTS_FILE);
+	fd2 = open(fpath, O_RDWR);
+	if (fd2 < 0) {
+		err("open");
+		return -1;
+	}
+	close(args->sync);
+	test_waitsig();
+
+	id1 = get_mntid(args->fd);
+	id2 = get_mntid(fd2);
+	if (id1 <0 || id2 < 0)
+		exit(1);
+
+	if (fstat(args->fd, &st1) || fstat(fd2, &st2)) {
+		err("stat");
+		exit(1);
+	}
+
+	test_msg("%d %d", id1, id2);
+
+#ifdef ZDTM_LINK_REMAP
+	if (st1.st_nlink != 1) {
+#else
+	if (st1.st_nlink != 0) {
+#endif
+		err("Wrong number of links: %d", st1.st_nlink);
+		exit(1);
+	}
+
+	if (id1 > 0 && id1 != id2 && st1.st_ino == st2.st_ino)
+		exit(AWK_OK);
+	else
+		exit(AWK_FAIL);
+}
+
+int main(int argc, char **argv)
+{
+	struct ns_exec_args args;
+	pid_t pid = -1;
+	char lpath[PATH_MAX], fpath[PATH_MAX];
+	char buf[256];
+	int p[2];
+
+	test_init(argc, argv);
+
+	if (mkdir(dirname, 0600) < 0) {
+		fail("Can't make zdtm_sys");
+		return 1;
+	}
+
+	if (mount("test", dirname, "tmpfs", 0, NULL)) {
+		err("mount");
+		return 1;
+	}
+
+	snprintf(fpath, sizeof(fpath), "%s/0", dirname);
+	if (mkdir(fpath, 0600) < 0) {
+		fail("Can't make zdtm_sys");
+		return 1;
+	}
+	if (mount("test", fpath, "tmpfs", 0, NULL)) {
+		err("mount");
+		return 1;
+	}
+
+	snprintf(lpath, sizeof(lpath), "%s/0/1", dirname);
+	if (mkdir(lpath, 0600) < 0) {
+		fail("Can't make zdtm_sys");
+		return 1;
+	}
+	snprintf(fpath, sizeof(fpath), "%s/1", dirname);
+	if (mkdir(fpath, 0600) < 0) {
+		fail("Can't make zdtm_sys");
+		return 1;
+	}
+	if (mount(lpath, fpath, NULL, MS_BIND, NULL)) {
+		err("mount");
+		return 1;
+	}
+	snprintf(lpath, sizeof(lpath), "%s/0/2", dirname);
+	if (mkdir(lpath, 0600) < 0) {
+		fail("Can't make zdtm_sys");
+		return 1;
+	}
+
+	if (pipe(p) == -1) {
+		err("pipe");
+		return 1;
+	}
+
+	if (getenv("ZDTM_NOSUBNS") == NULL) {
+		snprintf(fpath, sizeof(fpath), "%s/1/%s", dirname, MPTS_FILE);
+
+		args.fd = open(fpath, O_CREAT | O_RDWR, 0600);
+		if (args.fd < 0) {
+			fail("Can't open file");
+			return 1;
+		}
+		snprintf(fpath, sizeof(fpath), "%s/0/1/%s", dirname, MPTS_FILE);
+		snprintf(lpath, sizeof(fpath), "%s/0/2/%s", dirname, MPTS_FILE);
+		if (link(fpath, lpath) == -1) {
+			err("link");
+			return -1;
+		}
+#ifdef ZDTM_LINK_REMAP
+		snprintf(lpath, sizeof(fpath), "%s/0/%s", dirname, MPTS_FILE);
+		if (link(fpath, lpath) == -1) {
+			err("link");
+			return -1;
+		}
+#endif
+		args.sync = p[1];
+
+		pid = clone(ns_child, args.stack_ptr, CLONE_NEWNS | SIGCHLD, &args);
+		if (pid < 0) {
+			err("Unable to fork child");
+			return 1;
+		}
+
+		close(args.fd);
+	}
+
+	close(p[1]);
+	read(p[0], buf, sizeof(buf));
+
+	snprintf(fpath, sizeof(fpath), "%s/0/1/%s", dirname, MPTS_FILE);
+	if (unlink(fpath))
+		return 1;
+	snprintf(fpath, sizeof(fpath), "%s/0/2/%s", dirname, MPTS_FILE);
+	if (unlink(fpath))
+		return 1;
+
+	test_daemon();
+	test_waitsig();
+
+
+	if (pid > 0) {
+		kill(pid, SIGTERM);
+		int status = 1;
+		wait(&status);
+		if (WIFEXITED(status)) {
+			if (WEXITSTATUS(status) == AWK_OK)
+				pass();
+			else if (WEXITSTATUS(status) == AWK_FAIL)
+				fail("Mount ID not restored");
+			else
+				fail("Failed to check mount IDs (%d)", WEXITSTATUS(status));
+		} else
+			fail("Test died");
+	}
+
+	umount2(dirname, MNT_DETACH);
+	rmdir(dirname);
+	return 0;
+}

test/zdtm/live/static/mntns_link_remap.opts

+--link-remap