Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

4 files changed, 384 insertions, 0 deletions

diff --git a/tools/testing/selftests/move_mount_set_group/.gitignore b/tools/testing/selftests/move_mount_set_group/.gitignore
new file mode 100644
index 000000000..f5e339268
--- /dev/null
+++ b/tools/testing/selftests/move_mount_set_group/.gitignore
@@ -0,0 +1 @@
+move_mount_set_group_test
diff --git a/tools/testing/selftests/move_mount_set_group/Makefile b/tools/testing/selftests/move_mount_set_group/Makefile
new file mode 100644
index 000000000..94235846b
--- /dev/null
+++ b/tools/testing/selftests/move_mount_set_group/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for mount selftests.
+CFLAGS = -g $(KHDR_INCLUDES) -Wall -O2
+
+TEST_GEN_FILES += move_mount_set_group_test
+
+include ../lib.mk
diff --git a/tools/testing/selftests/move_mount_set_group/config b/tools/testing/selftests/move_mount_set_group/config
new file mode 100644
index 000000000..416bd53ce
--- /dev/null
+++ b/tools/testing/selftests/move_mount_set_group/config
@@ -0,0 +1 @@
+CONFIG_USER_NS=y
diff --git a/tools/testing/selftests/move_mount_set_group/move_mount_set_group_test.c b/tools/testing/selftests/move_mount_set_group/move_mount_set_group_test.c
new file mode 100644
index 000000000..50ed5d475
--- /dev/null
+++ b/tools/testing/selftests/move_mount_set_group/move_mount_set_group_test.c
@@ -0,0 +1,375 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <sys/syscall.h>
+
+#include "../kselftest_harness.h"
+
+#ifndef CLONE_NEWNS
+#define CLONE_NEWNS 0x00020000
+#endif
+
+#ifndef CLONE_NEWUSER
+#define CLONE_NEWUSER 0x10000000
+#endif
+
+#ifndef MS_SHARED
+#define MS_SHARED (1 << 20)
+#endif
+
+#ifndef MS_PRIVATE
+#define MS_PRIVATE (1<<18)
+#endif
+
+#ifndef MOVE_MOUNT_SET_GROUP
+#define MOVE_MOUNT_SET_GROUP 0x00000100
+#endif
+
+#ifndef MOVE_MOUNT_F_EMPTY_PATH
+#define MOVE_MOUNT_F_EMPTY_PATH 0x00000004
+#endif
+
+#ifndef MOVE_MOUNT_T_EMPTY_PATH
+#define MOVE_MOUNT_T_EMPTY_PATH 0x00000040
+#endif
+
+static ssize_t write_nointr(int fd, const void *buf, size_t count)
+{
+	ssize_t ret;
+
+	do {
+		ret = write(fd, buf, count);
+	} while (ret < 0 && errno == EINTR);
+
+	return ret;
+}
+
+static int write_file(const char *path, const void *buf, size_t count)
+{
+	int fd;
+	ssize_t ret;
+
+	fd = open(path, O_WRONLY | O_CLOEXEC | O_NOCTTY | O_NOFOLLOW);
+	if (fd < 0)
+		return -1;
+
+	ret = write_nointr(fd, buf, count);
+	close(fd);
+	if (ret < 0 || (size_t)ret != count)
+		return -1;
+
+	return 0;
+}
+
+static int create_and_enter_userns(void)
+{
+	uid_t uid;
+	gid_t gid;
+	char map[100];
+
+	uid = getuid();
+	gid = getgid();
+
+	if (unshare(CLONE_NEWUSER))
+		return -1;
+
+	if (write_file("/proc/self/setgroups", "deny", sizeof("deny") - 1) &&
+	    errno != ENOENT)
+		return -1;
+
+	snprintf(map, sizeof(map), "0 %d 1", uid);
+	if (write_file("/proc/self/uid_map", map, strlen(map)))
+		return -1;
+
+
+	snprintf(map, sizeof(map), "0 %d 1", gid);
+	if (write_file("/proc/self/gid_map", map, strlen(map)))
+		return -1;
+
+	if (setgid(0))
+		return -1;
+
+	if (setuid(0))
+		return -1;
+
+	return 0;
+}
+
+static int prepare_unpriv_mountns(void)
+{
+	if (create_and_enter_userns())
+		return -1;
+
+	if (unshare(CLONE_NEWNS))
+		return -1;
+
+	if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0))
+		return -1;
+
+	return 0;
+}
+
+static char *get_field(char *src, int nfields)
+{
+	int i;
+	char *p = src;
+
+	for (i = 0; i < nfields; i++) {
+		while (*p && *p != ' ' && *p != '\t')
+			p++;
+
+		if (!*p)
+			break;
+
+		p++;
+	}
+
+	return p;
+}
+
+static void null_endofword(char *word)
+{
+	while (*word && *word != ' ' && *word != '\t')
+		word++;
+	*word = '\0';
+}
+
+static bool is_shared_mount(const char *path)
+{
+	size_t len = 0;
+	char *line = NULL;
+	FILE *f = NULL;
+
+	f = fopen("/proc/self/mountinfo", "re");
+	if (!f)
+		return false;
+
+	while (getline(&line, &len, f) != -1) {
+		char *opts, *target;
+
+		target = get_field(line, 4);
+		if (!target)
+			continue;
+
+		opts = get_field(target, 2);
+		if (!opts)
+			continue;
+
+		null_endofword(target);
+
+		if (strcmp(target, path) != 0)
+			continue;
+
+		null_endofword(opts);
+		if (strstr(opts, "shared:"))
+			return true;
+	}
+
+	free(line);
+	fclose(f);
+
+	return false;
+}
+
+/* Attempt to de-conflict with the selftests tree. */
+#ifndef SKIP
+#define SKIP(s, ...)	XFAIL(s, ##__VA_ARGS__)
+#endif
+
+#define SET_GROUP_FROM	"/tmp/move_mount_set_group_supported_from"
+#define SET_GROUP_TO	"/tmp/move_mount_set_group_supported_to"
+
+static bool move_mount_set_group_supported(void)
+{
+	int ret;
+
+	if (mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV,
+		  "size=100000,mode=700"))
+		return -1;
+
+	if (mount(NULL, "/tmp", NULL, MS_PRIVATE, 0))
+		return -1;
+
+	if (mkdir(SET_GROUP_FROM, 0777))
+		return -1;
+
+	if (mkdir(SET_GROUP_TO, 0777))
+		return -1;
+
+	if (mount("testing", SET_GROUP_FROM, "tmpfs", MS_NOATIME | MS_NODEV,
+		  "size=100000,mode=700"))
+		return -1;
+
+	if (mount(SET_GROUP_FROM, SET_GROUP_TO, NULL, MS_BIND, NULL))
+		return -1;
+
+	if (mount(NULL, SET_GROUP_FROM, NULL, MS_SHARED, 0))
+		return -1;
+
+	ret = syscall(SYS_move_mount, AT_FDCWD, SET_GROUP_FROM,
+		      AT_FDCWD, SET_GROUP_TO, MOVE_MOUNT_SET_GROUP);
+	umount2("/tmp", MNT_DETACH);
+
+	return ret >= 0;
+}
+
+FIXTURE(move_mount_set_group) {
+};
+
+#define SET_GROUP_A "/tmp/A"
+
+FIXTURE_SETUP(move_mount_set_group)
+{
+	bool ret;
+
+	ASSERT_EQ(prepare_unpriv_mountns(), 0);
+
+	ret = move_mount_set_group_supported();
+	ASSERT_GE(ret, 0);
+	if (!ret)
+		SKIP(return, "move_mount(MOVE_MOUNT_SET_GROUP) is not supported");
+
+	umount2("/tmp", MNT_DETACH);
+
+	ASSERT_EQ(mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir(SET_GROUP_A, 0777), 0);
+
+	ASSERT_EQ(mount("testing", SET_GROUP_A, "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+}
+
+FIXTURE_TEARDOWN(move_mount_set_group)
+{
+	bool ret;
+
+	ret = move_mount_set_group_supported();
+	ASSERT_GE(ret, 0);
+	if (!ret)
+		SKIP(return, "move_mount(MOVE_MOUNT_SET_GROUP) is not supported");
+
+	umount2("/tmp", MNT_DETACH);
+}
+
+#define __STACK_SIZE (8 * 1024 * 1024)
+static pid_t do_clone(int (*fn)(void *), void *arg, int flags)
+{
+	void *stack;
+
+	stack = malloc(__STACK_SIZE);
+	if (!stack)
+		return -ENOMEM;
+
+#ifdef __ia64__
+	return __clone2(fn, stack, __STACK_SIZE, flags | SIGCHLD, arg, NULL);
+#else
+	return clone(fn, stack + __STACK_SIZE, flags | SIGCHLD, arg, NULL);
+#endif
+}
+
+static int wait_for_pid(pid_t pid)
+{
+	int status, ret;
+
+again:
+	ret = waitpid(pid, &status, 0);
+	if (ret == -1) {
+		if (errno == EINTR)
+			goto again;
+
+		return -1;
+	}
+
+	if (!WIFEXITED(status))
+		return -1;
+
+	return WEXITSTATUS(status);
+}
+
+struct child_args {
+	int unsfd;
+	int mntnsfd;
+	bool shared;
+	int mntfd;
+};
+
+static int get_nestedns_mount_cb(void *data)
+{
+	struct child_args *ca = (struct child_args *)data;
+	int ret;
+
+	ret = prepare_unpriv_mountns();
+	if (ret)
+		return 1;
+
+	if (ca->shared) {
+		ret = mount(NULL, SET_GROUP_A, NULL, MS_SHARED, 0);
+		if (ret)
+			return 1;
+	}
+
+	ret = open("/proc/self/ns/user", O_RDONLY);
+	if (ret < 0)
+		return 1;
+	ca->unsfd = ret;
+
+	ret = open("/proc/self/ns/mnt", O_RDONLY);
+	if (ret < 0)
+		return 1;
+	ca->mntnsfd = ret;
+
+	ret = open(SET_GROUP_A, O_RDONLY);
+	if (ret < 0)
+		return 1;
+	ca->mntfd = ret;
+
+	return 0;
+}
+
+TEST_F(move_mount_set_group, complex_sharing_copying)
+{
+	struct child_args ca_from = {
+		.shared = true,
+	};
+	struct child_args ca_to = {
+		.shared = false,
+	};
+	pid_t pid;
+	bool ret;
+
+	ret = move_mount_set_group_supported();
+	ASSERT_GE(ret, 0);
+	if (!ret)
+		SKIP(return, "move_mount(MOVE_MOUNT_SET_GROUP) is not supported");
+
+	pid = do_clone(get_nestedns_mount_cb, (void *)&ca_from, CLONE_VFORK |
+		       CLONE_VM | CLONE_FILES); ASSERT_GT(pid, 0);
+	ASSERT_EQ(wait_for_pid(pid), 0);
+
+	pid = do_clone(get_nestedns_mount_cb, (void *)&ca_to, CLONE_VFORK |
+		       CLONE_VM | CLONE_FILES); ASSERT_GT(pid, 0);
+	ASSERT_EQ(wait_for_pid(pid), 0);
+
+	ASSERT_EQ(syscall(SYS_move_mount, ca_from.mntfd, "",
+			  ca_to.mntfd, "", MOVE_MOUNT_SET_GROUP
+			  | MOVE_MOUNT_F_EMPTY_PATH | MOVE_MOUNT_T_EMPTY_PATH),
+		  0);
+
+	ASSERT_EQ(setns(ca_to.mntnsfd, CLONE_NEWNS), 0);
+	ASSERT_EQ(is_shared_mount(SET_GROUP_A), 1);
+}
+
+TEST_HARNESS_MAIN