linux-zen-desktop/tools/testing/selftests/landlock/fs_test.c

4427 lines
122 KiB
C
Raw Blame History

This file contains invisible Unicode characters!

This file contains invisible Unicode characters that may be processed differently from what appears below. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to reveal hidden characters.

// SPDX-License-Identifier: GPL-2.0
/*
* Landlock tests - Filesystem
*
* Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
* Copyright © 2020 ANSSI
* Copyright © 2020-2022 Microsoft Corporation
*/
#define _GNU_SOURCE
#include <fcntl.h>
#include <linux/landlock.h>
#include <sched.h>
#include <stdio.h>
#include <string.h>
#include <sys/capability.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/sendfile.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <unistd.h>
#include "common.h"
#ifndef renameat2
int renameat2(int olddirfd, const char *oldpath, int newdirfd,
const char *newpath, unsigned int flags)
{
return syscall(__NR_renameat2, olddirfd, oldpath, newdirfd, newpath,
flags);
}
#endif
#ifndef RENAME_EXCHANGE
#define RENAME_EXCHANGE (1 << 1)
#endif
#define TMP_DIR "tmp"
#define BINARY_PATH "./true"
/* Paths (sibling number and depth) */
static const char dir_s1d1[] = TMP_DIR "/s1d1";
static const char file1_s1d1[] = TMP_DIR "/s1d1/f1";
static const char file2_s1d1[] = TMP_DIR "/s1d1/f2";
static const char dir_s1d2[] = TMP_DIR "/s1d1/s1d2";
static const char file1_s1d2[] = TMP_DIR "/s1d1/s1d2/f1";
static const char file2_s1d2[] = TMP_DIR "/s1d1/s1d2/f2";
static const char dir_s1d3[] = TMP_DIR "/s1d1/s1d2/s1d3";
static const char file1_s1d3[] = TMP_DIR "/s1d1/s1d2/s1d3/f1";
static const char file2_s1d3[] = TMP_DIR "/s1d1/s1d2/s1d3/f2";
static const char dir_s2d1[] = TMP_DIR "/s2d1";
static const char file1_s2d1[] = TMP_DIR "/s2d1/f1";
static const char dir_s2d2[] = TMP_DIR "/s2d1/s2d2";
static const char file1_s2d2[] = TMP_DIR "/s2d1/s2d2/f1";
static const char dir_s2d3[] = TMP_DIR "/s2d1/s2d2/s2d3";
static const char file1_s2d3[] = TMP_DIR "/s2d1/s2d2/s2d3/f1";
static const char file2_s2d3[] = TMP_DIR "/s2d1/s2d2/s2d3/f2";
static const char dir_s3d1[] = TMP_DIR "/s3d1";
static const char file1_s3d1[] = TMP_DIR "/s3d1/f1";
/* dir_s3d2 is a mount point. */
static const char dir_s3d2[] = TMP_DIR "/s3d1/s3d2";
static const char dir_s3d3[] = TMP_DIR "/s3d1/s3d2/s3d3";
/*
* layout1 hierarchy:
*
* tmp
* ├── s1d1
* │   ├── f1
* │   ├── f2
* │   └── s1d2
* │   ├── f1
* │   ├── f2
* │   └── s1d3
* │   ├── f1
* │   └── f2
* ├── s2d1
* │   ├── f1
* │   └── s2d2
* │   ├── f1
* │   └── s2d3
* │   ├── f1
* │   └── f2
* └── s3d1
*    ├── f1
* └── s3d2
* └── s3d3
*/
static bool fgrep(FILE *const inf, const char *const str)
{
char line[32];
const int slen = strlen(str);
while (!feof(inf)) {
if (!fgets(line, sizeof(line), inf))
break;
if (strncmp(line, str, slen))
continue;
return true;
}
return false;
}
static bool supports_overlayfs(void)
{
bool res;
FILE *const inf = fopen("/proc/filesystems", "r");
/*
* Consider that the filesystem is supported if we cannot get the
* supported ones.
*/
if (!inf)
return true;
res = fgrep(inf, "nodev\toverlay\n");
fclose(inf);
return res;
}
static void mkdir_parents(struct __test_metadata *const _metadata,
const char *const path)
{
char *walker;
const char *parent;
int i, err;
ASSERT_NE(path[0], '\0');
walker = strdup(path);
ASSERT_NE(NULL, walker);
parent = walker;
for (i = 1; walker[i]; i++) {
if (walker[i] != '/')
continue;
walker[i] = '\0';
err = mkdir(parent, 0700);
ASSERT_FALSE(err && errno != EEXIST)
{
TH_LOG("Failed to create directory \"%s\": %s", parent,
strerror(errno));
}
walker[i] = '/';
}
free(walker);
}
static void create_directory(struct __test_metadata *const _metadata,
const char *const path)
{
mkdir_parents(_metadata, path);
ASSERT_EQ(0, mkdir(path, 0700))
{
TH_LOG("Failed to create directory \"%s\": %s", path,
strerror(errno));
}
}
static void create_file(struct __test_metadata *const _metadata,
const char *const path)
{
mkdir_parents(_metadata, path);
ASSERT_EQ(0, mknod(path, S_IFREG | 0700, 0))
{
TH_LOG("Failed to create file \"%s\": %s", path,
strerror(errno));
}
}
static int remove_path(const char *const path)
{
char *walker;
int i, ret, err = 0;
walker = strdup(path);
if (!walker) {
err = ENOMEM;
goto out;
}
if (unlink(path) && rmdir(path)) {
if (errno != ENOENT && errno != ENOTDIR)
err = errno;
goto out;
}
for (i = strlen(walker); i > 0; i--) {
if (walker[i] != '/')
continue;
walker[i] = '\0';
ret = rmdir(walker);
if (ret) {
if (errno != ENOTEMPTY && errno != EBUSY)
err = errno;
goto out;
}
if (strcmp(walker, TMP_DIR) == 0)
goto out;
}
out:
free(walker);
return err;
}
static void prepare_layout(struct __test_metadata *const _metadata)
{
disable_caps(_metadata);
umask(0077);
create_directory(_metadata, TMP_DIR);
/*
* Do not pollute the rest of the system: creates a private mount point
* for tests relying on pivot_root(2) and move_mount(2).
*/
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, unshare(CLONE_NEWNS));
ASSERT_EQ(0, mount("tmp", TMP_DIR, "tmpfs", 0, "size=4m,mode=700"));
ASSERT_EQ(0, mount(NULL, TMP_DIR, NULL, MS_PRIVATE | MS_REC, NULL));
clear_cap(_metadata, CAP_SYS_ADMIN);
}
static void cleanup_layout(struct __test_metadata *const _metadata)
{
set_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, umount(TMP_DIR));
clear_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, remove_path(TMP_DIR));
}
static void create_layout1(struct __test_metadata *const _metadata)
{
create_file(_metadata, file1_s1d1);
create_file(_metadata, file1_s1d2);
create_file(_metadata, file1_s1d3);
create_file(_metadata, file2_s1d1);
create_file(_metadata, file2_s1d2);
create_file(_metadata, file2_s1d3);
create_file(_metadata, file1_s2d1);
create_file(_metadata, file1_s2d2);
create_file(_metadata, file1_s2d3);
create_file(_metadata, file2_s2d3);
create_file(_metadata, file1_s3d1);
create_directory(_metadata, dir_s3d2);
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, mount("tmp", dir_s3d2, "tmpfs", 0, "size=4m,mode=700"));
clear_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, mkdir(dir_s3d3, 0700));
}
static void remove_layout1(struct __test_metadata *const _metadata)
{
EXPECT_EQ(0, remove_path(file2_s1d3));
EXPECT_EQ(0, remove_path(file2_s1d2));
EXPECT_EQ(0, remove_path(file2_s1d1));
EXPECT_EQ(0, remove_path(file1_s1d3));
EXPECT_EQ(0, remove_path(file1_s1d2));
EXPECT_EQ(0, remove_path(file1_s1d1));
EXPECT_EQ(0, remove_path(file2_s2d3));
EXPECT_EQ(0, remove_path(file1_s2d3));
EXPECT_EQ(0, remove_path(file1_s2d2));
EXPECT_EQ(0, remove_path(file1_s2d1));
EXPECT_EQ(0, remove_path(file1_s3d1));
EXPECT_EQ(0, remove_path(dir_s3d3));
set_cap(_metadata, CAP_SYS_ADMIN);
umount(dir_s3d2);
clear_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, remove_path(dir_s3d2));
}
/* clang-format off */
FIXTURE(layout1) {};
/* clang-format on */
FIXTURE_SETUP(layout1)
{
prepare_layout(_metadata);
create_layout1(_metadata);
}
FIXTURE_TEARDOWN(layout1)
{
remove_layout1(_metadata);
cleanup_layout(_metadata);
}
/*
* This helper enables to use the ASSERT_* macros and print the line number
* pointing to the test caller.
*/
static int test_open_rel(const int dirfd, const char *const path,
const int flags)
{
int fd;
/* Works with file and directories. */
fd = openat(dirfd, path, flags | O_CLOEXEC);
if (fd < 0)
return errno;
/*
* Mixing error codes from close(2) and open(2) should not lead to any
* (access type) confusion for this test.
*/
if (close(fd) != 0)
return errno;
return 0;
}
static int test_open(const char *const path, const int flags)
{
return test_open_rel(AT_FDCWD, path, flags);
}
TEST_F_FORK(layout1, no_restriction)
{
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(file2_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(file2_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s2d1, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s2d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s2d2, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s2d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s2d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s2d3, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d3, O_RDONLY));
}
TEST_F_FORK(layout1, inval)
{
struct landlock_path_beneath_attr path_beneath = {
.allowed_access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
.parent_fd = -1,
};
struct landlock_ruleset_attr ruleset_attr = {
.handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
};
int ruleset_fd;
path_beneath.parent_fd =
open(dir_s1d2, O_PATH | O_DIRECTORY | O_CLOEXEC);
ASSERT_LE(0, path_beneath.parent_fd);
ruleset_fd = open(dir_s1d1, O_PATH | O_DIRECTORY | O_CLOEXEC);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
/* Returns EBADF because ruleset_fd is not a landlock-ruleset FD. */
ASSERT_EQ(EBADF, errno);
ASSERT_EQ(0, close(ruleset_fd));
ruleset_fd = open(dir_s1d1, O_DIRECTORY | O_CLOEXEC);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
/* Returns EBADFD because ruleset_fd is not a valid ruleset. */
ASSERT_EQ(EBADFD, errno);
ASSERT_EQ(0, close(ruleset_fd));
/* Gets a real ruleset. */
ruleset_fd =
landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(0, close(path_beneath.parent_fd));
/* Tests without O_PATH. */
path_beneath.parent_fd = open(dir_s1d2, O_DIRECTORY | O_CLOEXEC);
ASSERT_LE(0, path_beneath.parent_fd);
ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(0, close(path_beneath.parent_fd));
/* Tests with a ruleset FD. */
path_beneath.parent_fd = ruleset_fd;
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(EBADFD, errno);
/* Checks unhandled allowed_access. */
path_beneath.parent_fd =
open(dir_s1d2, O_PATH | O_DIRECTORY | O_CLOEXEC);
ASSERT_LE(0, path_beneath.parent_fd);
/* Test with legitimate values. */
path_beneath.allowed_access |= LANDLOCK_ACCESS_FS_EXECUTE;
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(EINVAL, errno);
path_beneath.allowed_access &= ~LANDLOCK_ACCESS_FS_EXECUTE;
/* Tests with denied-by-default access right. */
path_beneath.allowed_access |= LANDLOCK_ACCESS_FS_REFER;
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(EINVAL, errno);
path_beneath.allowed_access &= ~LANDLOCK_ACCESS_FS_REFER;
/* Test with unknown (64-bits) value. */
path_beneath.allowed_access |= (1ULL << 60);
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(EINVAL, errno);
path_beneath.allowed_access &= ~(1ULL << 60);
/* Test with no access. */
path_beneath.allowed_access = 0;
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(ENOMSG, errno);
path_beneath.allowed_access &= ~(1ULL << 60);
ASSERT_EQ(0, close(path_beneath.parent_fd));
/* Enforces the ruleset. */
ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
ASSERT_EQ(0, landlock_restrict_self(ruleset_fd, 0));
ASSERT_EQ(0, close(ruleset_fd));
}
/* clang-format off */
#define ACCESS_FILE ( \
LANDLOCK_ACCESS_FS_EXECUTE | \
LANDLOCK_ACCESS_FS_WRITE_FILE | \
LANDLOCK_ACCESS_FS_READ_FILE | \
LANDLOCK_ACCESS_FS_TRUNCATE)
#define ACCESS_LAST LANDLOCK_ACCESS_FS_TRUNCATE
#define ACCESS_ALL ( \
ACCESS_FILE | \
LANDLOCK_ACCESS_FS_READ_DIR | \
LANDLOCK_ACCESS_FS_REMOVE_DIR | \
LANDLOCK_ACCESS_FS_REMOVE_FILE | \
LANDLOCK_ACCESS_FS_MAKE_CHAR | \
LANDLOCK_ACCESS_FS_MAKE_DIR | \
LANDLOCK_ACCESS_FS_MAKE_REG | \
LANDLOCK_ACCESS_FS_MAKE_SOCK | \
LANDLOCK_ACCESS_FS_MAKE_FIFO | \
LANDLOCK_ACCESS_FS_MAKE_BLOCK | \
LANDLOCK_ACCESS_FS_MAKE_SYM | \
LANDLOCK_ACCESS_FS_REFER)
/* clang-format on */
TEST_F_FORK(layout1, file_and_dir_access_rights)
{
__u64 access;
int err;
struct landlock_path_beneath_attr path_beneath_file = {},
path_beneath_dir = {};
struct landlock_ruleset_attr ruleset_attr = {
.handled_access_fs = ACCESS_ALL,
};
const int ruleset_fd =
landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
/* Tests access rights for files. */
path_beneath_file.parent_fd = open(file1_s1d2, O_PATH | O_CLOEXEC);
ASSERT_LE(0, path_beneath_file.parent_fd);
/* Tests access rights for directories. */
path_beneath_dir.parent_fd =
open(dir_s1d2, O_PATH | O_DIRECTORY | O_CLOEXEC);
ASSERT_LE(0, path_beneath_dir.parent_fd);
for (access = 1; access <= ACCESS_LAST; access <<= 1) {
path_beneath_dir.allowed_access = access;
ASSERT_EQ(0, landlock_add_rule(ruleset_fd,
LANDLOCK_RULE_PATH_BENEATH,
&path_beneath_dir, 0));
path_beneath_file.allowed_access = access;
err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath_file, 0);
if (access & ACCESS_FILE) {
ASSERT_EQ(0, err);
} else {
ASSERT_EQ(-1, err);
ASSERT_EQ(EINVAL, errno);
}
}
ASSERT_EQ(0, close(path_beneath_file.parent_fd));
ASSERT_EQ(0, close(path_beneath_dir.parent_fd));
ASSERT_EQ(0, close(ruleset_fd));
}
TEST_F_FORK(layout1, unknown_access_rights)
{
__u64 access_mask;
for (access_mask = 1ULL << 63; access_mask != ACCESS_LAST;
access_mask >>= 1) {
struct landlock_ruleset_attr ruleset_attr = {
.handled_access_fs = access_mask,
};
ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr,
sizeof(ruleset_attr), 0));
ASSERT_EQ(EINVAL, errno);
}
}
static void add_path_beneath(struct __test_metadata *const _metadata,
const int ruleset_fd, const __u64 allowed_access,
const char *const path)
{
struct landlock_path_beneath_attr path_beneath = {
.allowed_access = allowed_access,
};
path_beneath.parent_fd = open(path, O_PATH | O_CLOEXEC);
ASSERT_LE(0, path_beneath.parent_fd)
{
TH_LOG("Failed to open directory \"%s\": %s", path,
strerror(errno));
}
ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0))
{
TH_LOG("Failed to update the ruleset with \"%s\": %s", path,
strerror(errno));
}
ASSERT_EQ(0, close(path_beneath.parent_fd));
}
struct rule {
const char *path;
__u64 access;
};
/* clang-format off */
#define ACCESS_RO ( \
LANDLOCK_ACCESS_FS_READ_FILE | \
LANDLOCK_ACCESS_FS_READ_DIR)
#define ACCESS_RW ( \
ACCESS_RO | \
LANDLOCK_ACCESS_FS_WRITE_FILE)
/* clang-format on */
static int create_ruleset(struct __test_metadata *const _metadata,
const __u64 handled_access_fs,
const struct rule rules[])
{
int ruleset_fd, i;
struct landlock_ruleset_attr ruleset_attr = {
.handled_access_fs = handled_access_fs,
};
ASSERT_NE(NULL, rules)
{
TH_LOG("No rule list");
}
ASSERT_NE(NULL, rules[0].path)
{
TH_LOG("Empty rule list");
}
ruleset_fd =
landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd)
{
TH_LOG("Failed to create a ruleset: %s", strerror(errno));
}
for (i = 0; rules[i].path; i++) {
add_path_beneath(_metadata, ruleset_fd, rules[i].access,
rules[i].path);
}
return ruleset_fd;
}
static void enforce_ruleset(struct __test_metadata *const _metadata,
const int ruleset_fd)
{
ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
ASSERT_EQ(0, landlock_restrict_self(ruleset_fd, 0))
{
TH_LOG("Failed to enforce ruleset: %s", strerror(errno));
}
}
TEST_F_FORK(layout1, proc_nsfs)
{
const struct rule rules[] = {
{
.path = "/dev/null",
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
struct landlock_path_beneath_attr path_beneath;
const int ruleset_fd = create_ruleset(
_metadata, rules[0].access | LANDLOCK_ACCESS_FS_READ_DIR,
rules);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, test_open("/proc/self/ns/mnt", O_RDONLY));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(EACCES, test_open("/", O_RDONLY));
ASSERT_EQ(EACCES, test_open("/dev", O_RDONLY));
ASSERT_EQ(0, test_open("/dev/null", O_RDONLY));
ASSERT_EQ(EACCES, test_open("/dev/full", O_RDONLY));
ASSERT_EQ(EACCES, test_open("/proc", O_RDONLY));
ASSERT_EQ(EACCES, test_open("/proc/self", O_RDONLY));
ASSERT_EQ(EACCES, test_open("/proc/self/ns", O_RDONLY));
/*
* Because nsfs is an internal filesystem, /proc/self/ns/mnt is a
* disconnected path. Such path cannot be identified and must then be
* allowed.
*/
ASSERT_EQ(0, test_open("/proc/self/ns/mnt", O_RDONLY));
/*
* Checks that it is not possible to add nsfs-like filesystem
* references to a ruleset.
*/
path_beneath.allowed_access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
path_beneath.parent_fd = open("/proc/self/ns/mnt", O_PATH | O_CLOEXEC);
ASSERT_LE(0, path_beneath.parent_fd);
ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
&path_beneath, 0));
ASSERT_EQ(EBADFD, errno);
ASSERT_EQ(0, close(path_beneath.parent_fd));
}
TEST_F_FORK(layout1, unpriv)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = ACCESS_RO,
},
{},
};
int ruleset_fd;
drop_caps(_metadata);
ruleset_fd = create_ruleset(_metadata, ACCESS_RO, rules);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(-1, landlock_restrict_self(ruleset_fd, 0));
ASSERT_EQ(EPERM, errno);
/* enforce_ruleset() calls prctl(no_new_privs). */
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
}
TEST_F_FORK(layout1, effective_access)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = ACCESS_RO,
},
{
.path = file1_s2d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
char buf;
int reg_fd;
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Tests on a directory (with or without O_PATH). */
ASSERT_EQ(EACCES, test_open("/", O_RDONLY));
ASSERT_EQ(0, test_open("/", O_RDONLY | O_PATH));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY | O_PATH));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d1, O_RDONLY | O_PATH));
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
/* Tests on a file (with or without O_PATH). */
ASSERT_EQ(EACCES, test_open(dir_s2d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s2d2, O_RDONLY | O_PATH));
ASSERT_EQ(0, test_open(file1_s2d2, O_RDONLY));
/* Checks effective read and write actions. */
reg_fd = open(file1_s2d2, O_RDWR | O_CLOEXEC);
ASSERT_LE(0, reg_fd);
ASSERT_EQ(1, write(reg_fd, ".", 1));
ASSERT_LE(0, lseek(reg_fd, 0, SEEK_SET));
ASSERT_EQ(1, read(reg_fd, &buf, 1));
ASSERT_EQ('.', buf);
ASSERT_EQ(0, close(reg_fd));
/* Just in case, double-checks effective actions. */
reg_fd = open(file1_s2d2, O_RDONLY | O_CLOEXEC);
ASSERT_LE(0, reg_fd);
ASSERT_EQ(-1, write(reg_fd, &buf, 1));
ASSERT_EQ(EBADF, errno);
ASSERT_EQ(0, close(reg_fd));
}
TEST_F_FORK(layout1, unhandled_access)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = ACCESS_RO,
},
{},
};
/* Here, we only handle read accesses, not write accesses. */
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RO, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/*
* Because the policy does not handle LANDLOCK_ACCESS_FS_WRITE_FILE,
* opening for write-only should be allowed, but not read-write.
*/
ASSERT_EQ(0, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDWR));
ASSERT_EQ(0, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDWR));
}
TEST_F_FORK(layout1, ruleset_overlap)
{
const struct rule rules[] = {
/* These rules should be ORed among them. */
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_READ_DIR,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks s1d1 hierarchy. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Checks s1d2 hierarchy. */
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDWR));
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* Checks s1d3 hierarchy. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_WRONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_RDWR));
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
}
TEST_F_FORK(layout1, layer_rule_unions)
{
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
/* dir_s1d3 should allow READ_FILE and WRITE_FILE (O_RDWR). */
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
const struct rule layer2[] = {
/* Doesn't change anything from layer1. */
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
const struct rule layer3[] = {
/* Only allows write (but not read) to dir_s1d3. */
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks s1d1 hierarchy with layer1. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Checks s1d2 hierarchy with layer1. */
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Checks s1d3 hierarchy with layer1. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_WRONLY));
/* dir_s1d3 should allow READ_FILE and WRITE_FILE (O_RDWR). */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Doesn't change anything from layer1. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer2);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks s1d1 hierarchy with layer2. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Checks s1d2 hierarchy with layer2. */
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Checks s1d3 hierarchy with layer2. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_WRONLY));
/* dir_s1d3 should allow READ_FILE and WRITE_FILE (O_RDWR). */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Only allows write (but not read) to dir_s1d3. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer3);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks s1d1 hierarchy with layer3. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Checks s1d2 hierarchy with layer3. */
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Checks s1d3 hierarchy with layer3. */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_WRONLY));
/* dir_s1d3 should now deny READ_FILE and WRITE_FILE (O_RDWR). */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_RDWR));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
}
TEST_F_FORK(layout1, non_overlapping_accesses)
{
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{},
};
const struct rule layer2[] = {
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_REMOVE_FILE,
},
{},
};
int ruleset_fd;
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(0, unlink(file1_s1d2));
ruleset_fd =
create_ruleset(_metadata, LANDLOCK_ACCESS_FS_MAKE_REG, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(-1, mknod(file1_s1d1, S_IFREG | 0700, 0));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, mknod(file1_s1d2, S_IFREG | 0700, 0));
ASSERT_EQ(0, unlink(file1_s1d2));
ruleset_fd = create_ruleset(_metadata, LANDLOCK_ACCESS_FS_REMOVE_FILE,
layer2);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Unchanged accesses for file creation. */
ASSERT_EQ(-1, mknod(file1_s1d1, S_IFREG | 0700, 0));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, mknod(file1_s1d2, S_IFREG | 0700, 0));
/* Checks file removing. */
ASSERT_EQ(-1, unlink(file1_s1d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, unlink(file1_s1d3));
}
TEST_F_FORK(layout1, interleaved_masked_accesses)
{
/*
* Checks overly restrictive rules:
* layer 1: allows R s1d1/s1d2/s1d3/file1
* layer 2: allows RW s1d1/s1d2/s1d3
* allows W s1d1/s1d2
* denies R s1d1/s1d2
* layer 3: allows R s1d1
* layer 4: allows R s1d1/s1d2
* denies W s1d1/s1d2
* layer 5: allows R s1d1/s1d2
* layer 6: allows X ----
* layer 7: allows W s1d1/s1d2
* denies R s1d1/s1d2
*/
const struct rule layer1_read[] = {
/* Allows read access to file1_s1d3 with the first layer. */
{
.path = file1_s1d3,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{},
};
/* First rule with write restrictions. */
const struct rule layer2_read_write[] = {
/* Start by granting read-write access via its parent directory... */
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
/* ...but also denies read access via its grandparent directory. */
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
const struct rule layer3_read[] = {
/* Allows read access via its great-grandparent directory. */
{
.path = dir_s1d1,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{},
};
const struct rule layer4_read_write[] = {
/*
* Try to confuse the deny access by denying write (but not
* read) access via its grandparent directory.
*/
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{},
};
const struct rule layer5_read[] = {
/*
* Try to override layer2's deny read access by explicitly
* allowing read access via file1_s1d3's grandparent.
*/
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{},
};
const struct rule layer6_execute[] = {
/*
* Restricts an unrelated file hierarchy with a new access
* (non-overlapping) type.
*/
{
.path = dir_s2d1,
.access = LANDLOCK_ACCESS_FS_EXECUTE,
},
{},
};
const struct rule layer7_read_write[] = {
/*
* Finally, denies read access to file1_s1d3 via its
* grandparent.
*/
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
int ruleset_fd;
ruleset_fd = create_ruleset(_metadata, LANDLOCK_ACCESS_FS_READ_FILE,
layer1_read);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks that read access is granted for file1_s1d3 with layer 1. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDWR));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file2_s1d3, O_WRONLY));
ruleset_fd = create_ruleset(_metadata,
LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
layer2_read_write);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks that previous access rights are unchanged with layer 2. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDWR));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file2_s1d3, O_WRONLY));
ruleset_fd = create_ruleset(_metadata, LANDLOCK_ACCESS_FS_READ_FILE,
layer3_read);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks that previous access rights are unchanged with layer 3. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDWR));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file2_s1d3, O_WRONLY));
/* This time, denies write access for the file hierarchy. */
ruleset_fd = create_ruleset(_metadata,
LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
layer4_read_write);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/*
* Checks that the only change with layer 4 is that write access is
* denied.
*/
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_WRONLY));
ruleset_fd = create_ruleset(_metadata, LANDLOCK_ACCESS_FS_READ_FILE,
layer5_read);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks that previous access rights are unchanged with layer 5. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_RDONLY));
ruleset_fd = create_ruleset(_metadata, LANDLOCK_ACCESS_FS_EXECUTE,
layer6_execute);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks that previous access rights are unchanged with layer 6. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_RDONLY));
ruleset_fd = create_ruleset(_metadata,
LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
layer7_read_write);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks read access is now denied with layer 7. */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(file2_s1d3, O_RDONLY));
}
TEST_F_FORK(layout1, inherit_subset)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_READ_DIR,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* Write access is forbidden. */
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
/* Readdir access is allowed. */
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* Write access is forbidden. */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
/* Readdir access is allowed. */
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
/*
* Tests shared rule extension: the following rules should not grant
* any new access, only remove some. Once enforced, these rules are
* ANDed with the previous ones.
*/
add_path_beneath(_metadata, ruleset_fd, LANDLOCK_ACCESS_FS_WRITE_FILE,
dir_s1d2);
/*
* According to ruleset_fd, dir_s1d2 should now have the
* LANDLOCK_ACCESS_FS_READ_FILE and LANDLOCK_ACCESS_FS_WRITE_FILE
* access rights (even if this directory is opened a second time).
* However, when enforcing this updated ruleset, the ruleset tied to
* the current process (i.e. its domain) will still only have the
* dir_s1d2 with LANDLOCK_ACCESS_FS_READ_FILE and
* LANDLOCK_ACCESS_FS_READ_DIR accesses, but
* LANDLOCK_ACCESS_FS_WRITE_FILE must not be allowed because it would
* be a privilege escalation.
*/
enforce_ruleset(_metadata, ruleset_fd);
/* Same tests and results as above. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* It is still forbidden to write in file1_s1d2. */
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
/* Readdir access is still allowed. */
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* It is still forbidden to write in file1_s1d3. */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
/* Readdir access is still allowed. */
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
/*
* Try to get more privileges by adding new access rights to the parent
* directory: dir_s1d1.
*/
add_path_beneath(_metadata, ruleset_fd, ACCESS_RW, dir_s1d1);
enforce_ruleset(_metadata, ruleset_fd);
/* Same tests and results as above. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* It is still forbidden to write in file1_s1d2. */
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
/* Readdir access is still allowed. */
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* It is still forbidden to write in file1_s1d3. */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
/* Readdir access is still allowed. */
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
/*
* Now, dir_s1d3 get a new rule tied to it, only allowing
* LANDLOCK_ACCESS_FS_WRITE_FILE. The (kernel internal) difference is
* that there was no rule tied to it before.
*/
add_path_beneath(_metadata, ruleset_fd, LANDLOCK_ACCESS_FS_WRITE_FILE,
dir_s1d3);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/*
* Same tests and results as above, except for open(dir_s1d3) which is
* now denied because the new rule mask the rule previously inherited
* from dir_s1d2.
*/
/* Same tests and results as above. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
/* It is still forbidden to write in file1_s1d2. */
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
/* Readdir access is still allowed. */
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* It is still forbidden to write in file1_s1d3. */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
/*
* Readdir of dir_s1d3 is still allowed because of the OR policy inside
* the same layer.
*/
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
}
TEST_F_FORK(layout1, inherit_superset)
{
const struct rule rules[] = {
{
.path = dir_s1d3,
.access = ACCESS_RO,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
/* Readdir access is denied for dir_s1d2. */
ASSERT_EQ(EACCES, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* Readdir access is allowed for dir_s1d3. */
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
/* File access is allowed for file1_s1d3. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
/* Now dir_s1d2, parent of dir_s1d3, gets a new rule tied to it. */
add_path_beneath(_metadata, ruleset_fd,
LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_READ_DIR,
dir_s1d2);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Readdir access is still denied for dir_s1d2. */
ASSERT_EQ(EACCES, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* Readdir access is still allowed for dir_s1d3. */
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
/* File access is still allowed for file1_s1d3. */
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
}
TEST_F_FORK(layout1, max_layers)
{
int i, err;
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = ACCESS_RO,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
for (i = 0; i < 16; i++)
enforce_ruleset(_metadata, ruleset_fd);
for (i = 0; i < 2; i++) {
err = landlock_restrict_self(ruleset_fd, 0);
ASSERT_EQ(-1, err);
ASSERT_EQ(E2BIG, errno);
}
ASSERT_EQ(0, close(ruleset_fd));
}
TEST_F_FORK(layout1, empty_or_same_ruleset)
{
struct landlock_ruleset_attr ruleset_attr = {};
int ruleset_fd;
/* Tests empty handled_access_fs. */
ruleset_fd =
landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(-1, ruleset_fd);
ASSERT_EQ(ENOMSG, errno);
/* Enforces policy which deny read access to all files. */
ruleset_attr.handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE;
ruleset_fd =
landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY));
/* Nests a policy which deny read access to all directories. */
ruleset_attr.handled_access_fs = LANDLOCK_ACCESS_FS_READ_DIR;
ruleset_fd =
landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY));
/* Enforces a second time with the same ruleset. */
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
}
TEST_F_FORK(layout1, rule_on_mountpoint)
{
const struct rule rules[] = {
{
.path = dir_s1d1,
.access = ACCESS_RO,
},
{
/* dir_s3d2 is a mount point. */
.path = dir_s3d2,
.access = ACCESS_RO,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(dir_s2d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(dir_s3d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d3, O_RDONLY));
}
TEST_F_FORK(layout1, rule_over_mountpoint)
{
const struct rule rules[] = {
{
.path = dir_s1d1,
.access = ACCESS_RO,
},
{
/* dir_s3d2 is a mount point. */
.path = dir_s3d1,
.access = ACCESS_RO,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(dir_s2d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d3, O_RDONLY));
}
/*
* This test verifies that we can apply a landlock rule on the root directory
* (which might require special handling).
*/
TEST_F_FORK(layout1, rule_over_root_allow_then_deny)
{
struct rule rules[] = {
{
.path = "/",
.access = ACCESS_RO,
},
{},
};
int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks allowed access. */
ASSERT_EQ(0, test_open("/", O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY));
rules[0].access = LANDLOCK_ACCESS_FS_READ_FILE;
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks denied access (on a directory). */
ASSERT_EQ(EACCES, test_open("/", O_RDONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY));
}
TEST_F_FORK(layout1, rule_over_root_deny)
{
const struct rule rules[] = {
{
.path = "/",
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks denied access (on a directory). */
ASSERT_EQ(EACCES, test_open("/", O_RDONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY));
}
TEST_F_FORK(layout1, rule_inside_mount_ns)
{
const struct rule rules[] = {
{
.path = "s3d3",
.access = ACCESS_RO,
},
{},
};
int ruleset_fd;
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, syscall(__NR_pivot_root, dir_s3d2, dir_s3d3))
{
TH_LOG("Failed to pivot root: %s", strerror(errno));
};
ASSERT_EQ(0, chdir("/"));
clear_cap(_metadata, CAP_SYS_ADMIN);
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, test_open("s3d3", O_RDONLY));
ASSERT_EQ(EACCES, test_open("/", O_RDONLY));
}
TEST_F_FORK(layout1, mount_and_pivot)
{
const struct rule rules[] = {
{
.path = dir_s3d2,
.access = ACCESS_RO,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(-1, mount(NULL, dir_s3d2, NULL, MS_RDONLY, NULL));
ASSERT_EQ(EPERM, errno);
ASSERT_EQ(-1, syscall(__NR_pivot_root, dir_s3d2, dir_s3d3));
ASSERT_EQ(EPERM, errno);
clear_cap(_metadata, CAP_SYS_ADMIN);
}
TEST_F_FORK(layout1, move_mount)
{
const struct rule rules[] = {
{
.path = dir_s3d2,
.access = ACCESS_RO,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, syscall(__NR_move_mount, AT_FDCWD, dir_s3d2, AT_FDCWD,
dir_s1d2, 0))
{
TH_LOG("Failed to move mount: %s", strerror(errno));
}
ASSERT_EQ(0, syscall(__NR_move_mount, AT_FDCWD, dir_s1d2, AT_FDCWD,
dir_s3d2, 0));
clear_cap(_metadata, CAP_SYS_ADMIN);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(-1, syscall(__NR_move_mount, AT_FDCWD, dir_s3d2, AT_FDCWD,
dir_s1d2, 0));
ASSERT_EQ(EPERM, errno);
clear_cap(_metadata, CAP_SYS_ADMIN);
}
TEST_F_FORK(layout1, release_inodes)
{
const struct rule rules[] = {
{
.path = dir_s1d1,
.access = ACCESS_RO,
},
{
.path = dir_s3d2,
.access = ACCESS_RO,
},
{
.path = dir_s3d3,
.access = ACCESS_RO,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
ASSERT_LE(0, ruleset_fd);
/* Unmount a file hierarchy while it is being used by a ruleset. */
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, umount(dir_s3d2));
clear_cap(_metadata, CAP_SYS_ADMIN);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(dir_s3d2, O_RDONLY));
/* This dir_s3d3 would not be allowed and does not exist anyway. */
ASSERT_EQ(ENOENT, test_open(dir_s3d3, O_RDONLY));
}
enum relative_access {
REL_OPEN,
REL_CHDIR,
REL_CHROOT_ONLY,
REL_CHROOT_CHDIR,
};
static void test_relative_path(struct __test_metadata *const _metadata,
const enum relative_access rel)
{
/*
* Common layer to check that chroot doesn't ignore it (i.e. a chroot
* is not a disconnected root directory).
*/
const struct rule layer1_base[] = {
{
.path = TMP_DIR,
.access = ACCESS_RO,
},
{},
};
const struct rule layer2_subs[] = {
{
.path = dir_s1d2,
.access = ACCESS_RO,
},
{
.path = dir_s2d2,
.access = ACCESS_RO,
},
{},
};
int dirfd, ruleset_fd;
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer1_base);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer2_subs);
ASSERT_LE(0, ruleset_fd);
switch (rel) {
case REL_OPEN:
case REL_CHDIR:
break;
case REL_CHROOT_ONLY:
ASSERT_EQ(0, chdir(dir_s2d2));
break;
case REL_CHROOT_CHDIR:
ASSERT_EQ(0, chdir(dir_s1d2));
break;
default:
ASSERT_TRUE(false);
return;
}
set_cap(_metadata, CAP_SYS_CHROOT);
enforce_ruleset(_metadata, ruleset_fd);
switch (rel) {
case REL_OPEN:
dirfd = open(dir_s1d2, O_DIRECTORY);
ASSERT_LE(0, dirfd);
break;
case REL_CHDIR:
ASSERT_EQ(0, chdir(dir_s1d2));
dirfd = AT_FDCWD;
break;
case REL_CHROOT_ONLY:
/* Do chroot into dir_s1d2 (relative to dir_s2d2). */
ASSERT_EQ(0, chroot("../../s1d1/s1d2"))
{
TH_LOG("Failed to chroot: %s", strerror(errno));
}
dirfd = AT_FDCWD;
break;
case REL_CHROOT_CHDIR:
/* Do chroot into dir_s1d2. */
ASSERT_EQ(0, chroot("."))
{
TH_LOG("Failed to chroot: %s", strerror(errno));
}
dirfd = AT_FDCWD;
break;
}
ASSERT_EQ((rel == REL_CHROOT_CHDIR) ? 0 : EACCES,
test_open_rel(dirfd, "..", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, ".", O_RDONLY));
if (rel == REL_CHROOT_ONLY) {
/* The current directory is dir_s2d2. */
ASSERT_EQ(0, test_open_rel(dirfd, "./s2d3", O_RDONLY));
} else {
/* The current directory is dir_s1d2. */
ASSERT_EQ(0, test_open_rel(dirfd, "./s1d3", O_RDONLY));
}
if (rel == REL_CHROOT_ONLY || rel == REL_CHROOT_CHDIR) {
/* Checks the root dir_s1d2. */
ASSERT_EQ(0, test_open_rel(dirfd, "/..", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, "/", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, "/f1", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, "/s1d3", O_RDONLY));
}
if (rel != REL_CHROOT_CHDIR) {
ASSERT_EQ(EACCES, test_open_rel(dirfd, "../../s1d1", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, "../../s1d1/s1d2", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, "../../s1d1/s1d2/s1d3",
O_RDONLY));
ASSERT_EQ(EACCES, test_open_rel(dirfd, "../../s2d1", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, "../../s2d1/s2d2", O_RDONLY));
ASSERT_EQ(0, test_open_rel(dirfd, "../../s2d1/s2d2/s2d3",
O_RDONLY));
}
if (rel == REL_OPEN)
ASSERT_EQ(0, close(dirfd));
ASSERT_EQ(0, close(ruleset_fd));
}
TEST_F_FORK(layout1, relative_open)
{
test_relative_path(_metadata, REL_OPEN);
}
TEST_F_FORK(layout1, relative_chdir)
{
test_relative_path(_metadata, REL_CHDIR);
}
TEST_F_FORK(layout1, relative_chroot_only)
{
test_relative_path(_metadata, REL_CHROOT_ONLY);
}
TEST_F_FORK(layout1, relative_chroot_chdir)
{
test_relative_path(_metadata, REL_CHROOT_CHDIR);
}
static void copy_binary(struct __test_metadata *const _metadata,
const char *const dst_path)
{
int dst_fd, src_fd;
struct stat statbuf;
dst_fd = open(dst_path, O_WRONLY | O_TRUNC | O_CLOEXEC);
ASSERT_LE(0, dst_fd)
{
TH_LOG("Failed to open \"%s\": %s", dst_path, strerror(errno));
}
src_fd = open(BINARY_PATH, O_RDONLY | O_CLOEXEC);
ASSERT_LE(0, src_fd)
{
TH_LOG("Failed to open \"" BINARY_PATH "\": %s",
strerror(errno));
}
ASSERT_EQ(0, fstat(src_fd, &statbuf));
ASSERT_EQ(statbuf.st_size,
sendfile(dst_fd, src_fd, 0, statbuf.st_size));
ASSERT_EQ(0, close(src_fd));
ASSERT_EQ(0, close(dst_fd));
}
static void test_execute(struct __test_metadata *const _metadata, const int err,
const char *const path)
{
int status;
char *const argv[] = { (char *)path, NULL };
const pid_t child = fork();
ASSERT_LE(0, child);
if (child == 0) {
ASSERT_EQ(err ? -1 : 0, execve(path, argv, NULL))
{
TH_LOG("Failed to execute \"%s\": %s", path,
strerror(errno));
};
ASSERT_EQ(err, errno);
_exit(_metadata->passed ? 2 : 1);
return;
}
ASSERT_EQ(child, waitpid(child, &status, 0));
ASSERT_EQ(1, WIFEXITED(status));
ASSERT_EQ(err ? 2 : 0, WEXITSTATUS(status))
{
TH_LOG("Unexpected return code for \"%s\": %s", path,
strerror(errno));
};
}
TEST_F_FORK(layout1, execute)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_EXECUTE,
},
{},
};
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
copy_binary(_metadata, file1_s1d1);
copy_binary(_metadata, file1_s1d2);
copy_binary(_metadata, file1_s1d3);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d1, O_RDONLY));
test_execute(_metadata, EACCES, file1_s1d1);
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
test_execute(_metadata, 0, file1_s1d2);
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
test_execute(_metadata, 0, file1_s1d3);
}
TEST_F_FORK(layout1, link)
{
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{},
};
const struct rule layer2[] = {
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_REMOVE_FILE,
},
{},
};
int ruleset_fd = create_ruleset(_metadata, layer1[0].access, layer1);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlink(file1_s1d3));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(-1, link(file2_s1d1, file1_s1d1));
ASSERT_EQ(EACCES, errno);
/* Denies linking because of reparenting. */
ASSERT_EQ(-1, link(file1_s2d1, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, link(file2_s1d2, file1_s1d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, link(file2_s1d3, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(0, link(file2_s1d2, file1_s1d2));
ASSERT_EQ(0, link(file2_s1d3, file1_s1d3));
/* Prepares for next unlinks. */
ASSERT_EQ(0, unlink(file2_s1d2));
ASSERT_EQ(0, unlink(file2_s1d3));
ruleset_fd = create_ruleset(_metadata, layer2[0].access, layer2);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks that linkind doesn't require the ability to delete a file. */
ASSERT_EQ(0, link(file1_s1d2, file2_s1d2));
ASSERT_EQ(0, link(file1_s1d3, file2_s1d3));
}
static int test_rename(const char *const oldpath, const char *const newpath)
{
if (rename(oldpath, newpath))
return errno;
return 0;
}
static int test_exchange(const char *const oldpath, const char *const newpath)
{
if (renameat2(AT_FDCWD, oldpath, AT_FDCWD, newpath, RENAME_EXCHANGE))
return errno;
return 0;
}
TEST_F_FORK(layout1, rename_file)
{
const struct rule rules[] = {
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_REMOVE_FILE,
},
{
.path = dir_s2d2,
.access = LANDLOCK_ACCESS_FS_REMOVE_FILE,
},
{},
};
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, unlink(file1_s1d2));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/*
* Tries to replace a file, from a directory that allows file removal,
* but to a different directory (which also allows file removal).
*/
ASSERT_EQ(-1, rename(file1_s2d3, file1_s1d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d3, AT_FDCWD, file1_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d3, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
/*
* Tries to replace a file, from a directory that denies file removal,
* to a different directory (which allows file removal).
*/
ASSERT_EQ(-1, rename(file1_s2d1, file1_s1d3));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d1, AT_FDCWD, file1_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s2d2, AT_FDCWD, file1_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
/* Exchanges files and directories that partially allow removal. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s2d2, AT_FDCWD, file1_s2d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Checks that file1_s2d1 cannot be removed (instead of ENOTDIR). */
ASSERT_EQ(-1, rename(dir_s2d2, file1_s2d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d1, AT_FDCWD, dir_s2d2,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Checks that file1_s1d1 cannot be removed (instead of EISDIR). */
ASSERT_EQ(-1, rename(file1_s1d1, dir_s1d2));
ASSERT_EQ(EACCES, errno);
/* Renames files with different parents. */
ASSERT_EQ(-1, rename(file1_s2d2, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(0, unlink(file1_s1d3));
ASSERT_EQ(-1, rename(file1_s2d1, file1_s1d3));
ASSERT_EQ(EACCES, errno);
/* Exchanges and renames files with same parent. */
ASSERT_EQ(0, renameat2(AT_FDCWD, file2_s2d3, AT_FDCWD, file1_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(0, rename(file2_s2d3, file1_s2d3));
/* Exchanges files and directories with same parent, twice. */
ASSERT_EQ(0, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(0, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_s2d3,
RENAME_EXCHANGE));
}
TEST_F_FORK(layout1, rename_dir)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_REMOVE_DIR,
},
{
.path = dir_s2d1,
.access = LANDLOCK_ACCESS_FS_REMOVE_DIR,
},
{},
};
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
/* Empties dir_s1d3 to allow renaming. */
ASSERT_EQ(0, unlink(file1_s1d3));
ASSERT_EQ(0, unlink(file2_s1d3));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Exchanges and renames directory to a different parent. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s2d3, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(dir_s2d3, dir_s1d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
/*
* Exchanges directory to the same parent, which doesn't allow
* directory removal.
*/
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s1d1, AT_FDCWD, dir_s2d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Checks that dir_s1d2 cannot be removed (instead of ENOTDIR). */
ASSERT_EQ(-1, rename(dir_s1d2, file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s1d1, AT_FDCWD, dir_s1d2,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Checks that dir_s1d2 cannot be removed (instead of EISDIR). */
ASSERT_EQ(-1, rename(file1_s1d1, dir_s1d2));
ASSERT_EQ(EACCES, errno);
/*
* Exchanges and renames directory to the same parent, which allows
* directory removal.
*/
ASSERT_EQ(0, renameat2(AT_FDCWD, dir_s1d3, AT_FDCWD, file1_s1d2,
RENAME_EXCHANGE));
ASSERT_EQ(0, unlink(dir_s1d3));
ASSERT_EQ(0, mkdir(dir_s1d3, 0700));
ASSERT_EQ(0, rename(file1_s1d2, dir_s1d3));
ASSERT_EQ(0, rmdir(dir_s1d3));
}
TEST_F_FORK(layout1, reparent_refer)
{
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = dir_s2d2,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{},
};
int ruleset_fd =
create_ruleset(_metadata, LANDLOCK_ACCESS_FS_REFER, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(-1, rename(dir_s1d2, dir_s2d1));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(dir_s1d2, dir_s2d2));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(dir_s1d2, dir_s2d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(dir_s1d3, dir_s2d1));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(dir_s1d3, dir_s2d2));
ASSERT_EQ(EXDEV, errno);
/*
* Moving should only be allowed when the source and the destination
* parent directory have REFER.
*/
ASSERT_EQ(-1, rename(dir_s1d3, dir_s2d3));
ASSERT_EQ(ENOTEMPTY, errno);
ASSERT_EQ(0, unlink(file1_s2d3));
ASSERT_EQ(0, unlink(file2_s2d3));
ASSERT_EQ(0, rename(dir_s1d3, dir_s2d3));
}
/* Checks renames beneath dir_s1d1. */
static void refer_denied_by_default(struct __test_metadata *const _metadata,
const struct rule layer1[],
const int layer1_err,
const struct rule layer2[])
{
int ruleset_fd;
ASSERT_EQ(0, unlink(file1_s1d2));
ruleset_fd = create_ruleset(_metadata, layer1[0].access, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/*
* If the first layer handles LANDLOCK_ACCESS_FS_REFER (according to
* layer1_err), then it allows some different-parent renames and links.
*/
ASSERT_EQ(layer1_err, test_rename(file1_s1d1, file1_s1d2));
if (layer1_err == 0)
ASSERT_EQ(layer1_err, test_rename(file1_s1d2, file1_s1d1));
ASSERT_EQ(layer1_err, test_exchange(file2_s1d1, file2_s1d2));
ASSERT_EQ(layer1_err, test_exchange(file2_s1d2, file2_s1d1));
ruleset_fd = create_ruleset(_metadata, layer2[0].access, layer2);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/*
* Now, either the first or the second layer does not handle
* LANDLOCK_ACCESS_FS_REFER, which means that any different-parent
* renames and links are denied, thus making the layer handling
* LANDLOCK_ACCESS_FS_REFER null and void.
*/
ASSERT_EQ(EXDEV, test_rename(file1_s1d1, file1_s1d2));
ASSERT_EQ(EXDEV, test_exchange(file2_s1d1, file2_s1d2));
ASSERT_EQ(EXDEV, test_exchange(file2_s1d2, file2_s1d1));
}
const struct rule layer_dir_s1d1_refer[] = {
{
.path = dir_s1d1,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{},
};
const struct rule layer_dir_s1d1_execute[] = {
{
/* Matches a parent directory. */
.path = dir_s1d1,
.access = LANDLOCK_ACCESS_FS_EXECUTE,
},
{},
};
const struct rule layer_dir_s2d1_execute[] = {
{
/* Does not match a parent directory. */
.path = dir_s2d1,
.access = LANDLOCK_ACCESS_FS_EXECUTE,
},
{},
};
/*
* Tests precedence over renames: denied by default for different parent
* directories, *with* a rule matching a parent directory, but not directly
* denying access (with MAKE_REG nor REMOVE).
*/
TEST_F_FORK(layout1, refer_denied_by_default1)
{
refer_denied_by_default(_metadata, layer_dir_s1d1_refer, 0,
layer_dir_s1d1_execute);
}
/*
* Same test but this time turning around the ABI version order: the first
* layer does not handle LANDLOCK_ACCESS_FS_REFER.
*/
TEST_F_FORK(layout1, refer_denied_by_default2)
{
refer_denied_by_default(_metadata, layer_dir_s1d1_execute, EXDEV,
layer_dir_s1d1_refer);
}
/*
* Tests precedence over renames: denied by default for different parent
* directories, *without* a rule matching a parent directory, but not directly
* denying access (with MAKE_REG nor REMOVE).
*/
TEST_F_FORK(layout1, refer_denied_by_default3)
{
refer_denied_by_default(_metadata, layer_dir_s1d1_refer, 0,
layer_dir_s2d1_execute);
}
/*
* Same test but this time turning around the ABI version order: the first
* layer does not handle LANDLOCK_ACCESS_FS_REFER.
*/
TEST_F_FORK(layout1, refer_denied_by_default4)
{
refer_denied_by_default(_metadata, layer_dir_s2d1_execute, EXDEV,
layer_dir_s1d1_refer);
}
TEST_F_FORK(layout1, reparent_link)
{
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = dir_s2d2,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = dir_s2d3,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{},
};
const int ruleset_fd = create_ruleset(
_metadata,
LANDLOCK_ACCESS_FS_MAKE_REG | LANDLOCK_ACCESS_FS_REFER, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlink(file1_s1d3));
/* Denies linking because of missing MAKE_REG. */
ASSERT_EQ(-1, link(file2_s1d1, file1_s1d1));
ASSERT_EQ(EACCES, errno);
/* Denies linking because of missing source and destination REFER. */
ASSERT_EQ(-1, link(file1_s2d1, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
/* Denies linking because of missing source REFER. */
ASSERT_EQ(-1, link(file1_s2d1, file1_s1d3));
ASSERT_EQ(EXDEV, errno);
/* Denies linking because of missing MAKE_REG. */
ASSERT_EQ(-1, link(file1_s2d2, file1_s1d1));
ASSERT_EQ(EACCES, errno);
/* Denies linking because of missing destination REFER. */
ASSERT_EQ(-1, link(file1_s2d2, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
/* Allows linking because of REFER and MAKE_REG. */
ASSERT_EQ(0, link(file1_s2d2, file1_s1d3));
ASSERT_EQ(0, unlink(file1_s2d2));
/* Reverse linking denied because of missing MAKE_REG. */
ASSERT_EQ(-1, link(file1_s1d3, file1_s2d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, unlink(file1_s2d3));
/* Checks reverse linking. */
ASSERT_EQ(0, link(file1_s1d3, file1_s2d3));
ASSERT_EQ(0, unlink(file1_s1d3));
/*
* This is OK for a file link, but it should not be allowed for a
* directory rename (because of the superset of access rights.
*/
ASSERT_EQ(0, link(file1_s2d3, file1_s1d3));
ASSERT_EQ(0, unlink(file1_s1d3));
ASSERT_EQ(-1, link(file2_s1d2, file1_s1d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, link(file2_s1d3, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(0, link(file2_s1d2, file1_s1d2));
ASSERT_EQ(0, link(file2_s1d3, file1_s1d3));
}
TEST_F_FORK(layout1, reparent_rename)
{
/* Same rules as for reparent_link. */
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = dir_s2d2,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = dir_s2d3,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{},
};
const int ruleset_fd = create_ruleset(
_metadata,
LANDLOCK_ACCESS_FS_MAKE_REG | LANDLOCK_ACCESS_FS_REFER, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlink(file1_s1d3));
/* Denies renaming because of missing MAKE_REG. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, file2_s1d1, AT_FDCWD, file1_s1d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s1d1, AT_FDCWD, file2_s1d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(-1, rename(file2_s1d1, file1_s1d1));
ASSERT_EQ(EACCES, errno);
/* Even denies same file exchange. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, file2_s1d1, AT_FDCWD, file2_s1d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Denies renaming because of missing source and destination REFER. */
ASSERT_EQ(-1, rename(file1_s2d1, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
/*
* Denies renaming because of missing MAKE_REG, source and destination
* REFER.
*/
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d1, AT_FDCWD, file2_s1d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file2_s1d1, AT_FDCWD, file1_s2d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Denies renaming because of missing source REFER. */
ASSERT_EQ(-1, rename(file1_s2d1, file1_s1d3));
ASSERT_EQ(EXDEV, errno);
/* Denies renaming because of missing MAKE_REG. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d1, AT_FDCWD, file2_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Denies renaming because of missing MAKE_REG. */
ASSERT_EQ(-1, rename(file1_s2d2, file1_s1d1));
ASSERT_EQ(EACCES, errno);
/* Denies renaming because of missing destination REFER*/
ASSERT_EQ(-1, rename(file1_s2d2, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
/* Denies exchange because of one missing MAKE_REG. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, file2_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Allows renaming because of REFER and MAKE_REG. */
ASSERT_EQ(0, rename(file1_s2d2, file1_s1d3));
/* Reverse renaming denied because of missing MAKE_REG. */
ASSERT_EQ(-1, rename(file1_s1d3, file1_s2d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, unlink(file1_s2d3));
ASSERT_EQ(0, rename(file1_s1d3, file1_s2d3));
/* Tests reverse renaming. */
ASSERT_EQ(0, rename(file1_s2d3, file1_s1d3));
ASSERT_EQ(0, renameat2(AT_FDCWD, file2_s2d3, AT_FDCWD, file1_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(0, rename(file1_s1d3, file1_s2d3));
/*
* This is OK for a file rename, but it should not be allowed for a
* directory rename (because of the superset of access rights).
*/
ASSERT_EQ(0, rename(file1_s2d3, file1_s1d3));
ASSERT_EQ(0, rename(file1_s1d3, file1_s2d3));
/*
* Tests superset restrictions applied to directories. Not only the
* dir_s2d3's parent (dir_s2d2) should be taken into account but also
* access rights tied to dir_s2d3. dir_s2d2 is missing one access right
* compared to dir_s1d3/file1_s1d3 (MAKE_REG) but it is provided
* directly by the moved dir_s2d3.
*/
ASSERT_EQ(0, rename(dir_s2d3, file1_s1d3));
ASSERT_EQ(0, rename(file1_s1d3, dir_s2d3));
/*
* The first rename is allowed but not the exchange because dir_s1d3's
* parent (dir_s1d2) doesn't have REFER.
*/
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d3, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s1d3, AT_FDCWD, file1_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(file1_s2d3, dir_s1d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(file2_s1d2, file1_s1d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(file2_s1d3, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
/* Renaming in the same directory is always allowed. */
ASSERT_EQ(0, rename(file2_s1d2, file1_s1d2));
ASSERT_EQ(0, rename(file2_s1d3, file1_s1d3));
ASSERT_EQ(0, unlink(file1_s1d2));
/* Denies because of missing source MAKE_REG and destination REFER. */
ASSERT_EQ(-1, rename(dir_s2d3, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(0, unlink(file1_s1d3));
/* Denies because of missing source MAKE_REG and REFER. */
ASSERT_EQ(-1, rename(dir_s2d2, file1_s1d3));
ASSERT_EQ(EXDEV, errno);
}
static void
reparent_exdev_layers_enforce1(struct __test_metadata *const _metadata)
{
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
/* Interesting for the layer2 tests. */
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{
.path = dir_s2d2,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = dir_s2d3,
.access = LANDLOCK_ACCESS_FS_MAKE_REG,
},
{},
};
const int ruleset_fd = create_ruleset(
_metadata,
LANDLOCK_ACCESS_FS_MAKE_REG | LANDLOCK_ACCESS_FS_REFER, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
}
static void
reparent_exdev_layers_enforce2(struct __test_metadata *const _metadata)
{
const struct rule layer2[] = {
{
.path = dir_s2d3,
.access = LANDLOCK_ACCESS_FS_MAKE_DIR,
},
{},
};
/*
* Same checks as before but with a second layer and a new MAKE_DIR
* rule (and no explicit handling of REFER).
*/
const int ruleset_fd =
create_ruleset(_metadata, LANDLOCK_ACCESS_FS_MAKE_DIR, layer2);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
}
TEST_F_FORK(layout1, reparent_exdev_layers_rename1)
{
ASSERT_EQ(0, unlink(file1_s2d2));
ASSERT_EQ(0, unlink(file1_s2d3));
reparent_exdev_layers_enforce1(_metadata);
/*
* Moving the dir_s1d3 directory below dir_s2d2 is allowed by Landlock
* because it doesn't inherit new access rights.
*/
ASSERT_EQ(0, rename(dir_s1d3, file1_s2d2));
ASSERT_EQ(0, rename(file1_s2d2, dir_s1d3));
/*
* Moving the dir_s1d3 directory below dir_s2d3 is allowed, even if it
* gets a new inherited access rights (MAKE_REG), because MAKE_REG is
* already allowed for dir_s1d3.
*/
ASSERT_EQ(0, rename(dir_s1d3, file1_s2d3));
ASSERT_EQ(0, rename(file1_s2d3, dir_s1d3));
/*
* However, moving the file1_s1d3 file below dir_s2d3 is allowed
* because it cannot inherit MAKE_REG right (which is dedicated to
* directories).
*/
ASSERT_EQ(0, rename(file1_s1d3, file1_s2d3));
reparent_exdev_layers_enforce2(_metadata);
/*
* Moving the dir_s1d3 directory below dir_s2d2 is now denied because
* MAKE_DIR is not tied to dir_s2d2.
*/
ASSERT_EQ(-1, rename(dir_s1d3, file1_s2d2));
ASSERT_EQ(EACCES, errno);
/*
* Moving the dir_s1d3 directory below dir_s2d3 is forbidden because it
* would grants MAKE_REG and MAKE_DIR rights to it.
*/
ASSERT_EQ(-1, rename(dir_s1d3, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
/*
* Moving the file2_s1d3 file below dir_s2d3 is denied because the
* second layer does not handle REFER, which is always denied by
* default.
*/
ASSERT_EQ(-1, rename(file2_s1d3, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
}
TEST_F_FORK(layout1, reparent_exdev_layers_rename2)
{
reparent_exdev_layers_enforce1(_metadata);
/* Checks EACCES predominance over EXDEV. */
ASSERT_EQ(-1, rename(file1_s1d1, file1_s2d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rename(file1_s1d2, file1_s2d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rename(file1_s1d1, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
/* Modify layout! */
ASSERT_EQ(0, rename(file1_s1d2, file1_s2d3));
/* Without REFER source. */
ASSERT_EQ(-1, rename(dir_s1d1, file1_s2d2));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, rename(dir_s1d2, file1_s2d2));
ASSERT_EQ(EXDEV, errno);
reparent_exdev_layers_enforce2(_metadata);
/* Checks EACCES predominance over EXDEV. */
ASSERT_EQ(-1, rename(file1_s1d1, file1_s2d2));
ASSERT_EQ(EACCES, errno);
/* Checks with actual file2_s1d2. */
ASSERT_EQ(-1, rename(file2_s1d2, file1_s2d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rename(file1_s1d1, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
/*
* Modifying the layout is now denied because the second layer does not
* handle REFER, which is always denied by default.
*/
ASSERT_EQ(-1, rename(file2_s1d2, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
/* Without REFER source, EACCES wins over EXDEV. */
ASSERT_EQ(-1, rename(dir_s1d1, file1_s2d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rename(dir_s1d2, file1_s2d2));
ASSERT_EQ(EACCES, errno);
}
TEST_F_FORK(layout1, reparent_exdev_layers_exchange1)
{
const char *const dir_file1_s1d2 = file1_s1d2, *const dir_file2_s2d3 =
file2_s2d3;
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, mkdir(file1_s1d2, 0700));
ASSERT_EQ(0, unlink(file2_s2d3));
ASSERT_EQ(0, mkdir(file2_s2d3, 0700));
reparent_exdev_layers_enforce1(_metadata);
/* Error predominance with file exchange: returns EXDEV and EACCES. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s1d1, AT_FDCWD, file1_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d3, AT_FDCWD, file1_s1d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/*
* Checks with directories which creation could be allowed, but denied
* because of access rights that would be inherited.
*/
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file1_s1d2, AT_FDCWD,
dir_file2_s2d3, RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file2_s2d3, AT_FDCWD,
dir_file1_s1d2, RENAME_EXCHANGE));
ASSERT_EQ(EXDEV, errno);
/* Checks with same access rights. */
ASSERT_EQ(0, renameat2(AT_FDCWD, dir_s1d3, AT_FDCWD, dir_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(0, renameat2(AT_FDCWD, dir_s2d3, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
/* Checks with different (child-only) access rights. */
ASSERT_EQ(0, renameat2(AT_FDCWD, dir_s2d3, AT_FDCWD, dir_file1_s1d2,
RENAME_EXCHANGE));
ASSERT_EQ(0, renameat2(AT_FDCWD, dir_file1_s1d2, AT_FDCWD, dir_s2d3,
RENAME_EXCHANGE));
/*
* Checks that exchange between file and directory are consistent.
*
* Moving a file (file1_s2d2) to a directory which only grants more
* directory-related access rights is allowed, and at the same time
* moving a directory (dir_file2_s2d3) to another directory which
* grants less access rights is allowed too.
*
* See layout1.reparent_exdev_layers_exchange3 for inverted arguments.
*/
ASSERT_EQ(0, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_file2_s2d3,
RENAME_EXCHANGE));
/*
* However, moving back the directory is denied because it would get
* more access rights than the current state and because file creation
* is forbidden (in dir_s2d2).
*/
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file2_s2d3, AT_FDCWD, file1_s2d2,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_file2_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
reparent_exdev_layers_enforce2(_metadata);
/* Error predominance with file exchange: returns EXDEV and EACCES. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s1d1, AT_FDCWD, file1_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d3, AT_FDCWD, file1_s1d1,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Checks with directories which creation is now denied. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file1_s1d2, AT_FDCWD,
dir_file2_s2d3, RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file2_s2d3, AT_FDCWD,
dir_file1_s1d2, RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Checks with different (child-only) access rights. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s1d3, AT_FDCWD, dir_s2d3,
RENAME_EXCHANGE));
/* Denied because of MAKE_DIR. */
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s2d3, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Checks with different (child-only) access rights. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_s2d3, AT_FDCWD, dir_file1_s1d2,
RENAME_EXCHANGE));
/* Denied because of MAKE_DIR. */
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file1_s1d2, AT_FDCWD, dir_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* See layout1.reparent_exdev_layers_exchange2 for complement. */
}
TEST_F_FORK(layout1, reparent_exdev_layers_exchange2)
{
const char *const dir_file2_s2d3 = file2_s2d3;
ASSERT_EQ(0, unlink(file2_s2d3));
ASSERT_EQ(0, mkdir(file2_s2d3, 0700));
reparent_exdev_layers_enforce1(_metadata);
reparent_exdev_layers_enforce2(_metadata);
/* Checks that exchange between file and directory are consistent. */
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_file2_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file2_s2d3, AT_FDCWD, file1_s2d2,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
}
TEST_F_FORK(layout1, reparent_exdev_layers_exchange3)
{
const char *const dir_file2_s2d3 = file2_s2d3;
ASSERT_EQ(0, unlink(file2_s2d3));
ASSERT_EQ(0, mkdir(file2_s2d3, 0700));
reparent_exdev_layers_enforce1(_metadata);
/*
* Checks that exchange between file and directory are consistent,
* including with inverted arguments (see
* layout1.reparent_exdev_layers_exchange1).
*/
ASSERT_EQ(0, renameat2(AT_FDCWD, dir_file2_s2d3, AT_FDCWD, file1_s2d2,
RENAME_EXCHANGE));
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_file2_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, dir_file2_s2d3, AT_FDCWD, file1_s2d2,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
}
TEST_F_FORK(layout1, reparent_remove)
{
const struct rule layer1[] = {
{
.path = dir_s1d1,
.access = LANDLOCK_ACCESS_FS_REFER |
LANDLOCK_ACCESS_FS_REMOVE_DIR,
},
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_REMOVE_FILE,
},
{
.path = dir_s2d1,
.access = LANDLOCK_ACCESS_FS_REFER |
LANDLOCK_ACCESS_FS_REMOVE_FILE,
},
{},
};
const int ruleset_fd = create_ruleset(
_metadata,
LANDLOCK_ACCESS_FS_REFER | LANDLOCK_ACCESS_FS_REMOVE_DIR |
LANDLOCK_ACCESS_FS_REMOVE_FILE,
layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Access denied because of wrong/swapped remove file/dir. */
ASSERT_EQ(-1, rename(file1_s1d1, dir_s2d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rename(dir_s2d2, file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s1d1, AT_FDCWD, dir_s2d2,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s1d1, AT_FDCWD, dir_s2d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
/* Access allowed thanks to the matching rights. */
ASSERT_EQ(-1, rename(file1_s2d1, dir_s1d2));
ASSERT_EQ(EISDIR, errno);
ASSERT_EQ(-1, rename(dir_s1d2, file1_s2d1));
ASSERT_EQ(ENOTDIR, errno);
ASSERT_EQ(-1, rename(dir_s1d3, file1_s2d1));
ASSERT_EQ(ENOTDIR, errno);
ASSERT_EQ(0, unlink(file1_s2d1));
ASSERT_EQ(0, unlink(file1_s1d3));
ASSERT_EQ(0, unlink(file2_s1d3));
ASSERT_EQ(0, rename(dir_s1d3, file1_s2d1));
/* Effectively removes a file and a directory by exchanging them. */
ASSERT_EQ(0, mkdir(dir_s1d3, 0700));
ASSERT_EQ(0, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(-1, renameat2(AT_FDCWD, file1_s2d2, AT_FDCWD, dir_s1d3,
RENAME_EXCHANGE));
ASSERT_EQ(EACCES, errno);
}
TEST_F_FORK(layout1, reparent_dom_superset)
{
const struct rule layer1[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = file1_s1d2,
.access = LANDLOCK_ACCESS_FS_EXECUTE,
},
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_MAKE_SOCK |
LANDLOCK_ACCESS_FS_EXECUTE,
},
{
.path = dir_s2d2,
.access = LANDLOCK_ACCESS_FS_REFER |
LANDLOCK_ACCESS_FS_EXECUTE |
LANDLOCK_ACCESS_FS_MAKE_SOCK,
},
{
.path = dir_s2d3,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_MAKE_FIFO,
},
{},
};
int ruleset_fd = create_ruleset(_metadata,
LANDLOCK_ACCESS_FS_REFER |
LANDLOCK_ACCESS_FS_EXECUTE |
LANDLOCK_ACCESS_FS_MAKE_SOCK |
LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_MAKE_FIFO,
layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(-1, rename(file1_s1d2, file1_s2d1));
ASSERT_EQ(EXDEV, errno);
/*
* Moving file1_s1d2 beneath dir_s2d3 would grant it the READ_FILE
* access right.
*/
ASSERT_EQ(-1, rename(file1_s1d2, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
/*
* Moving file1_s1d2 should be allowed even if dir_s2d2 grants a
* superset of access rights compared to dir_s1d2, because file1_s1d2
* already has these access rights anyway.
*/
ASSERT_EQ(0, rename(file1_s1d2, file1_s2d2));
ASSERT_EQ(0, rename(file1_s2d2, file1_s1d2));
ASSERT_EQ(-1, rename(dir_s1d3, file1_s2d1));
ASSERT_EQ(EXDEV, errno);
/*
* Moving dir_s1d3 beneath dir_s2d3 would grant it the MAKE_FIFO access
* right.
*/
ASSERT_EQ(-1, rename(dir_s1d3, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
/*
* Moving dir_s1d3 should be allowed even if dir_s2d2 grants a superset
* of access rights compared to dir_s1d2, because dir_s1d3 already has
* these access rights anyway.
*/
ASSERT_EQ(0, rename(dir_s1d3, file1_s2d2));
ASSERT_EQ(0, rename(file1_s2d2, dir_s1d3));
/*
* Moving file1_s2d3 beneath dir_s1d2 is allowed, but moving it back
* will be denied because the new inherited access rights from dir_s1d2
* will be less than the destination (original) dir_s2d3. This is a
* sinkhole scenario where we cannot move back files or directories.
*/
ASSERT_EQ(0, rename(file1_s2d3, file2_s1d2));
ASSERT_EQ(-1, rename(file2_s1d2, file1_s2d3));
ASSERT_EQ(EXDEV, errno);
ASSERT_EQ(0, unlink(file2_s1d2));
ASSERT_EQ(0, unlink(file2_s2d3));
/*
* Checks similar directory one-way move: dir_s2d3 loses EXECUTE and
* MAKE_SOCK which were inherited from dir_s1d3.
*/
ASSERT_EQ(0, rename(dir_s2d3, file2_s1d2));
ASSERT_EQ(-1, rename(file2_s1d2, dir_s2d3));
ASSERT_EQ(EXDEV, errno);
}
TEST_F_FORK(layout1, remove_dir)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_REMOVE_DIR,
},
{},
};
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlink(file1_s1d3));
ASSERT_EQ(0, unlink(file2_s1d3));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(0, rmdir(dir_s1d3));
ASSERT_EQ(0, mkdir(dir_s1d3, 0700));
ASSERT_EQ(0, unlinkat(AT_FDCWD, dir_s1d3, AT_REMOVEDIR));
/* dir_s1d2 itself cannot be removed. */
ASSERT_EQ(-1, rmdir(dir_s1d2));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, unlinkat(AT_FDCWD, dir_s1d2, AT_REMOVEDIR));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rmdir(dir_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, unlinkat(AT_FDCWD, dir_s1d1, AT_REMOVEDIR));
ASSERT_EQ(EACCES, errno);
}
TEST_F_FORK(layout1, remove_file)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_REMOVE_FILE,
},
{},
};
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(-1, unlink(file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, unlinkat(AT_FDCWD, file1_s1d1, 0));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlinkat(AT_FDCWD, file1_s1d3, 0));
}
static void test_make_file(struct __test_metadata *const _metadata,
const __u64 access, const mode_t mode,
const dev_t dev)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = access,
},
{},
};
const int ruleset_fd = create_ruleset(_metadata, access, rules);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(0, unlink(file2_s1d1));
ASSERT_EQ(0, mknod(file2_s1d1, mode | 0400, dev))
{
TH_LOG("Failed to make file \"%s\": %s", file2_s1d1,
strerror(errno));
};
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlink(file2_s1d2));
ASSERT_EQ(0, unlink(file1_s1d3));
ASSERT_EQ(0, unlink(file2_s1d3));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(-1, mknod(file1_s1d1, mode | 0400, dev));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, link(file2_s1d1, file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rename(file2_s1d1, file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, mknod(file1_s1d2, mode | 0400, dev))
{
TH_LOG("Failed to make file \"%s\": %s", file1_s1d2,
strerror(errno));
};
ASSERT_EQ(0, link(file1_s1d2, file2_s1d2));
ASSERT_EQ(0, unlink(file2_s1d2));
ASSERT_EQ(0, rename(file1_s1d2, file2_s1d2));
ASSERT_EQ(0, mknod(file1_s1d3, mode | 0400, dev));
ASSERT_EQ(0, link(file1_s1d3, file2_s1d3));
ASSERT_EQ(0, unlink(file2_s1d3));
ASSERT_EQ(0, rename(file1_s1d3, file2_s1d3));
}
TEST_F_FORK(layout1, make_char)
{
/* Creates a /dev/null device. */
set_cap(_metadata, CAP_MKNOD);
test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_CHAR, S_IFCHR,
makedev(1, 3));
}
TEST_F_FORK(layout1, make_block)
{
/* Creates a /dev/loop0 device. */
set_cap(_metadata, CAP_MKNOD);
test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_BLOCK, S_IFBLK,
makedev(7, 0));
}
TEST_F_FORK(layout1, make_reg_1)
{
test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_REG, S_IFREG, 0);
}
TEST_F_FORK(layout1, make_reg_2)
{
test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_REG, 0, 0);
}
TEST_F_FORK(layout1, make_sock)
{
test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_SOCK, S_IFSOCK, 0);
}
TEST_F_FORK(layout1, make_fifo)
{
test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_FIFO, S_IFIFO, 0);
}
TEST_F_FORK(layout1, make_sym)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_MAKE_SYM,
},
{},
};
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(0, unlink(file2_s1d1));
ASSERT_EQ(0, symlink("none", file2_s1d1));
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlink(file2_s1d2));
ASSERT_EQ(0, unlink(file1_s1d3));
ASSERT_EQ(0, unlink(file2_s1d3));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(-1, symlink("none", file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, link(file2_s1d1, file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(-1, rename(file2_s1d1, file1_s1d1));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, symlink("none", file1_s1d2));
ASSERT_EQ(0, link(file1_s1d2, file2_s1d2));
ASSERT_EQ(0, unlink(file2_s1d2));
ASSERT_EQ(0, rename(file1_s1d2, file2_s1d2));
ASSERT_EQ(0, symlink("none", file1_s1d3));
ASSERT_EQ(0, link(file1_s1d3, file2_s1d3));
ASSERT_EQ(0, unlink(file2_s1d3));
ASSERT_EQ(0, rename(file1_s1d3, file2_s1d3));
}
TEST_F_FORK(layout1, make_dir)
{
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_MAKE_DIR,
},
{},
};
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
ASSERT_EQ(0, unlink(file1_s1d1));
ASSERT_EQ(0, unlink(file1_s1d2));
ASSERT_EQ(0, unlink(file1_s1d3));
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Uses file_* as directory names. */
ASSERT_EQ(-1, mkdir(file1_s1d1, 0700));
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, mkdir(file1_s1d2, 0700));
ASSERT_EQ(0, mkdir(file1_s1d3, 0700));
}
static int open_proc_fd(struct __test_metadata *const _metadata, const int fd,
const int open_flags)
{
static const char path_template[] = "/proc/self/fd/%d";
char procfd_path[sizeof(path_template) + 10];
const int procfd_path_size =
snprintf(procfd_path, sizeof(procfd_path), path_template, fd);
ASSERT_LT(procfd_path_size, sizeof(procfd_path));
return open(procfd_path, open_flags);
}
TEST_F_FORK(layout1, proc_unlinked_file)
{
const struct rule rules[] = {
{
.path = file1_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{},
};
int reg_fd, proc_fd;
const int ruleset_fd = create_ruleset(
_metadata,
LANDLOCK_ACCESS_FS_READ_FILE | LANDLOCK_ACCESS_FS_WRITE_FILE,
rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_RDWR));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
reg_fd = open(file1_s1d2, O_RDONLY | O_CLOEXEC);
ASSERT_LE(0, reg_fd);
ASSERT_EQ(0, unlink(file1_s1d2));
proc_fd = open_proc_fd(_metadata, reg_fd, O_RDONLY | O_CLOEXEC);
ASSERT_LE(0, proc_fd);
ASSERT_EQ(0, close(proc_fd));
proc_fd = open_proc_fd(_metadata, reg_fd, O_RDWR | O_CLOEXEC);
ASSERT_EQ(-1, proc_fd)
{
TH_LOG("Successfully opened /proc/self/fd/%d: %s", reg_fd,
strerror(errno));
}
ASSERT_EQ(EACCES, errno);
ASSERT_EQ(0, close(reg_fd));
}
TEST_F_FORK(layout1, proc_pipe)
{
int proc_fd;
int pipe_fds[2];
char buf = '\0';
const struct rule rules[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
/* Limits read and write access to files tied to the filesystem. */
const int ruleset_fd =
create_ruleset(_metadata, rules[0].access, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks enforcement for normal files. */
ASSERT_EQ(0, test_open(file1_s1d2, O_RDWR));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDWR));
/* Checks access to pipes through FD. */
ASSERT_EQ(0, pipe2(pipe_fds, O_CLOEXEC));
ASSERT_EQ(1, write(pipe_fds[1], ".", 1))
{
TH_LOG("Failed to write in pipe: %s", strerror(errno));
}
ASSERT_EQ(1, read(pipe_fds[0], &buf, 1));
ASSERT_EQ('.', buf);
/* Checks write access to pipe through /proc/self/fd . */
proc_fd = open_proc_fd(_metadata, pipe_fds[1], O_WRONLY | O_CLOEXEC);
ASSERT_LE(0, proc_fd);
ASSERT_EQ(1, write(proc_fd, ".", 1))
{
TH_LOG("Failed to write through /proc/self/fd/%d: %s",
pipe_fds[1], strerror(errno));
}
ASSERT_EQ(0, close(proc_fd));
/* Checks read access to pipe through /proc/self/fd . */
proc_fd = open_proc_fd(_metadata, pipe_fds[0], O_RDONLY | O_CLOEXEC);
ASSERT_LE(0, proc_fd);
buf = '\0';
ASSERT_EQ(1, read(proc_fd, &buf, 1))
{
TH_LOG("Failed to read through /proc/self/fd/%d: %s",
pipe_fds[1], strerror(errno));
}
ASSERT_EQ(0, close(proc_fd));
ASSERT_EQ(0, close(pipe_fds[0]));
ASSERT_EQ(0, close(pipe_fds[1]));
}
/* Invokes truncate(2) and returns its errno or 0. */
static int test_truncate(const char *const path)
{
if (truncate(path, 10) < 0)
return errno;
return 0;
}
/*
* Invokes creat(2) and returns its errno or 0.
* Closes the opened file descriptor on success.
*/
static int test_creat(const char *const path)
{
int fd = creat(path, 0600);
if (fd < 0)
return errno;
/*
* Mixing error codes from close(2) and creat(2) should not lead to any
* (access type) confusion for this test.
*/
if (close(fd) < 0)
return errno;
return 0;
}
/*
* Exercises file truncation when it's not restricted,
* as it was the case before LANDLOCK_ACCESS_FS_TRUNCATE existed.
*/
TEST_F_FORK(layout1, truncate_unhandled)
{
const char *const file_r = file1_s1d1;
const char *const file_w = file2_s1d1;
const char *const file_none = file1_s1d2;
const struct rule rules[] = {
{
.path = file_r,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = file_w,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
/* Implicitly: No rights for file_none. */
{},
};
const __u64 handled = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE;
int ruleset_fd;
/* Enable Landlock. */
ruleset_fd = create_ruleset(_metadata, handled, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/*
* Checks read right: truncate and open with O_TRUNC work, unless the
* file is attempted to be opened for writing.
*/
EXPECT_EQ(0, test_truncate(file_r));
EXPECT_EQ(0, test_open(file_r, O_RDONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_open(file_r, O_WRONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_creat(file_r));
/*
* Checks write right: truncate and open with O_TRUNC work, unless the
* file is attempted to be opened for reading.
*/
EXPECT_EQ(0, test_truncate(file_w));
EXPECT_EQ(EACCES, test_open(file_w, O_RDONLY | O_TRUNC));
EXPECT_EQ(0, test_open(file_w, O_WRONLY | O_TRUNC));
EXPECT_EQ(0, test_creat(file_w));
/*
* Checks "no rights" case: truncate works but all open attempts fail,
* including creat.
*/
EXPECT_EQ(0, test_truncate(file_none));
EXPECT_EQ(EACCES, test_open(file_none, O_RDONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_open(file_none, O_WRONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_creat(file_none));
}
TEST_F_FORK(layout1, truncate)
{
const char *const file_rwt = file1_s1d1;
const char *const file_rw = file2_s1d1;
const char *const file_rt = file1_s1d2;
const char *const file_t = file2_s1d2;
const char *const file_none = file1_s1d3;
const char *const dir_t = dir_s2d1;
const char *const file_in_dir_t = file1_s2d1;
const char *const dir_w = dir_s3d1;
const char *const file_in_dir_w = file1_s3d1;
const struct rule rules[] = {
{
.path = file_rwt,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE |
LANDLOCK_ACCESS_FS_TRUNCATE,
},
{
.path = file_rw,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{
.path = file_rt,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_TRUNCATE,
},
{
.path = file_t,
.access = LANDLOCK_ACCESS_FS_TRUNCATE,
},
/* Implicitly: No access rights for file_none. */
{
.path = dir_t,
.access = LANDLOCK_ACCESS_FS_TRUNCATE,
},
{
.path = dir_w,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
const __u64 handled = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE |
LANDLOCK_ACCESS_FS_TRUNCATE;
int ruleset_fd;
/* Enable Landlock. */
ruleset_fd = create_ruleset(_metadata, handled, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks read, write and truncate rights: truncation works. */
EXPECT_EQ(0, test_truncate(file_rwt));
EXPECT_EQ(0, test_open(file_rwt, O_RDONLY | O_TRUNC));
EXPECT_EQ(0, test_open(file_rwt, O_WRONLY | O_TRUNC));
/* Checks read and write rights: no truncate variant works. */
EXPECT_EQ(EACCES, test_truncate(file_rw));
EXPECT_EQ(EACCES, test_open(file_rw, O_RDONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_open(file_rw, O_WRONLY | O_TRUNC));
/*
* Checks read and truncate rights: truncation works.
*
* Note: Files can get truncated using open() even with O_RDONLY.
*/
EXPECT_EQ(0, test_truncate(file_rt));
EXPECT_EQ(0, test_open(file_rt, O_RDONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_open(file_rt, O_WRONLY | O_TRUNC));
/* Checks truncate right: truncate works, but can't open file. */
EXPECT_EQ(0, test_truncate(file_t));
EXPECT_EQ(EACCES, test_open(file_t, O_RDONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_open(file_t, O_WRONLY | O_TRUNC));
/* Checks "no rights" case: No form of truncation works. */
EXPECT_EQ(EACCES, test_truncate(file_none));
EXPECT_EQ(EACCES, test_open(file_none, O_RDONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_open(file_none, O_WRONLY | O_TRUNC));
/*
* Checks truncate right on directory: truncate works on contained
* files.
*/
EXPECT_EQ(0, test_truncate(file_in_dir_t));
EXPECT_EQ(EACCES, test_open(file_in_dir_t, O_RDONLY | O_TRUNC));
EXPECT_EQ(EACCES, test_open(file_in_dir_t, O_WRONLY | O_TRUNC));
/*
* Checks creat in dir_w: This requires the truncate right when
* overwriting an existing file, but does not require it when the file
* is new.
*/
EXPECT_EQ(EACCES, test_creat(file_in_dir_w));
ASSERT_EQ(0, unlink(file_in_dir_w));
EXPECT_EQ(0, test_creat(file_in_dir_w));
}
/* Invokes ftruncate(2) and returns its errno or 0. */
static int test_ftruncate(int fd)
{
if (ftruncate(fd, 10) < 0)
return errno;
return 0;
}
TEST_F_FORK(layout1, ftruncate)
{
/*
* This test opens a new file descriptor at different stages of
* Landlock restriction:
*
* without restriction: ftruncate works
* something else but truncate restricted: ftruncate works
* truncate restricted and permitted: ftruncate works
* truncate restricted and not permitted: ftruncate fails
*
* Whether this works or not is expected to depend on the time when the
* FD was opened, not to depend on the time when ftruncate() was
* called.
*/
const char *const path = file1_s1d1;
const __u64 handled1 = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE;
const struct rule layer1[] = {
{
.path = path,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
const __u64 handled2 = LANDLOCK_ACCESS_FS_TRUNCATE;
const struct rule layer2[] = {
{
.path = path,
.access = LANDLOCK_ACCESS_FS_TRUNCATE,
},
{},
};
const __u64 handled3 = LANDLOCK_ACCESS_FS_TRUNCATE |
LANDLOCK_ACCESS_FS_WRITE_FILE;
const struct rule layer3[] = {
{
.path = path,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
int fd_layer0, fd_layer1, fd_layer2, fd_layer3, ruleset_fd;
fd_layer0 = open(path, O_WRONLY);
EXPECT_EQ(0, test_ftruncate(fd_layer0));
ruleset_fd = create_ruleset(_metadata, handled1, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
fd_layer1 = open(path, O_WRONLY);
EXPECT_EQ(0, test_ftruncate(fd_layer0));
EXPECT_EQ(0, test_ftruncate(fd_layer1));
ruleset_fd = create_ruleset(_metadata, handled2, layer2);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
fd_layer2 = open(path, O_WRONLY);
EXPECT_EQ(0, test_ftruncate(fd_layer0));
EXPECT_EQ(0, test_ftruncate(fd_layer1));
EXPECT_EQ(0, test_ftruncate(fd_layer2));
ruleset_fd = create_ruleset(_metadata, handled3, layer3);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
fd_layer3 = open(path, O_WRONLY);
EXPECT_EQ(0, test_ftruncate(fd_layer0));
EXPECT_EQ(0, test_ftruncate(fd_layer1));
EXPECT_EQ(0, test_ftruncate(fd_layer2));
EXPECT_EQ(EACCES, test_ftruncate(fd_layer3));
ASSERT_EQ(0, close(fd_layer0));
ASSERT_EQ(0, close(fd_layer1));
ASSERT_EQ(0, close(fd_layer2));
ASSERT_EQ(0, close(fd_layer3));
}
/* clang-format off */
FIXTURE(ftruncate) {};
/* clang-format on */
FIXTURE_SETUP(ftruncate)
{
prepare_layout(_metadata);
create_file(_metadata, file1_s1d1);
}
FIXTURE_TEARDOWN(ftruncate)
{
EXPECT_EQ(0, remove_path(file1_s1d1));
cleanup_layout(_metadata);
}
FIXTURE_VARIANT(ftruncate)
{
const __u64 handled;
const __u64 permitted;
const int expected_open_result;
const int expected_ftruncate_result;
};
/* clang-format off */
FIXTURE_VARIANT_ADD(ftruncate, w_w) {
/* clang-format on */
.handled = LANDLOCK_ACCESS_FS_WRITE_FILE,
.permitted = LANDLOCK_ACCESS_FS_WRITE_FILE,
.expected_open_result = 0,
.expected_ftruncate_result = 0,
};
/* clang-format off */
FIXTURE_VARIANT_ADD(ftruncate, t_t) {
/* clang-format on */
.handled = LANDLOCK_ACCESS_FS_TRUNCATE,
.permitted = LANDLOCK_ACCESS_FS_TRUNCATE,
.expected_open_result = 0,
.expected_ftruncate_result = 0,
};
/* clang-format off */
FIXTURE_VARIANT_ADD(ftruncate, wt_w) {
/* clang-format on */
.handled = LANDLOCK_ACCESS_FS_WRITE_FILE | LANDLOCK_ACCESS_FS_TRUNCATE,
.permitted = LANDLOCK_ACCESS_FS_WRITE_FILE,
.expected_open_result = 0,
.expected_ftruncate_result = EACCES,
};
/* clang-format off */
FIXTURE_VARIANT_ADD(ftruncate, wt_wt) {
/* clang-format on */
.handled = LANDLOCK_ACCESS_FS_WRITE_FILE | LANDLOCK_ACCESS_FS_TRUNCATE,
.permitted = LANDLOCK_ACCESS_FS_WRITE_FILE |
LANDLOCK_ACCESS_FS_TRUNCATE,
.expected_open_result = 0,
.expected_ftruncate_result = 0,
};
/* clang-format off */
FIXTURE_VARIANT_ADD(ftruncate, wt_t) {
/* clang-format on */
.handled = LANDLOCK_ACCESS_FS_WRITE_FILE | LANDLOCK_ACCESS_FS_TRUNCATE,
.permitted = LANDLOCK_ACCESS_FS_TRUNCATE,
.expected_open_result = EACCES,
};
TEST_F_FORK(ftruncate, open_and_ftruncate)
{
const char *const path = file1_s1d1;
const struct rule rules[] = {
{
.path = path,
.access = variant->permitted,
},
{},
};
int fd, ruleset_fd;
/* Enable Landlock. */
ruleset_fd = create_ruleset(_metadata, variant->handled, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
fd = open(path, O_WRONLY);
EXPECT_EQ(variant->expected_open_result, (fd < 0 ? errno : 0));
if (fd >= 0) {
EXPECT_EQ(variant->expected_ftruncate_result,
test_ftruncate(fd));
ASSERT_EQ(0, close(fd));
}
}
TEST_F_FORK(ftruncate, open_and_ftruncate_in_different_processes)
{
int child, fd, status;
int socket_fds[2];
ASSERT_EQ(0, socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0,
socket_fds));
child = fork();
ASSERT_LE(0, child);
if (child == 0) {
/*
* Enables Landlock in the child process, open a file descriptor
* where truncation is forbidden and send it to the
* non-landlocked parent process.
*/
const char *const path = file1_s1d1;
const struct rule rules[] = {
{
.path = path,
.access = variant->permitted,
},
{},
};
int fd, ruleset_fd;
ruleset_fd = create_ruleset(_metadata, variant->handled, rules);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
fd = open(path, O_WRONLY);
ASSERT_EQ(variant->expected_open_result, (fd < 0 ? errno : 0));
if (fd >= 0) {
ASSERT_EQ(0, send_fd(socket_fds[0], fd));
ASSERT_EQ(0, close(fd));
}
ASSERT_EQ(0, close(socket_fds[0]));
_exit(_metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
return;
}
if (variant->expected_open_result == 0) {
fd = recv_fd(socket_fds[1]);
ASSERT_LE(0, fd);
EXPECT_EQ(variant->expected_ftruncate_result,
test_ftruncate(fd));
ASSERT_EQ(0, close(fd));
}
ASSERT_EQ(child, waitpid(child, &status, 0));
ASSERT_EQ(1, WIFEXITED(status));
ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status));
ASSERT_EQ(0, close(socket_fds[0]));
ASSERT_EQ(0, close(socket_fds[1]));
}
TEST(memfd_ftruncate)
{
int fd;
fd = memfd_create("name", MFD_CLOEXEC);
ASSERT_LE(0, fd);
/*
* Checks that ftruncate is permitted on file descriptors that are
* created in ways other than open(2).
*/
EXPECT_EQ(0, test_ftruncate(fd));
ASSERT_EQ(0, close(fd));
}
/* clang-format off */
FIXTURE(layout1_bind) {};
/* clang-format on */
FIXTURE_SETUP(layout1_bind)
{
prepare_layout(_metadata);
create_layout1(_metadata);
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, mount(dir_s1d2, dir_s2d2, NULL, MS_BIND, NULL));
clear_cap(_metadata, CAP_SYS_ADMIN);
}
FIXTURE_TEARDOWN(layout1_bind)
{
set_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, umount(dir_s2d2));
clear_cap(_metadata, CAP_SYS_ADMIN);
remove_layout1(_metadata);
cleanup_layout(_metadata);
}
static const char bind_dir_s1d3[] = TMP_DIR "/s2d1/s2d2/s1d3";
static const char bind_file1_s1d3[] = TMP_DIR "/s2d1/s2d2/s1d3/f1";
/*
* layout1_bind hierarchy:
*
* tmp
* ├── s1d1
* │   ├── f1
* │   ├── f2
* │   └── s1d2
* │   ├── f1
* │   ├── f2
* │   └── s1d3
* │   ├── f1
* │   └── f2
* ├── s2d1
* │   ├── f1
* │   └── s2d2
* │   ├── f1
* │   ├── f2
* │   └── s1d3
* │   ├── f1
* │   └── f2
* └── s3d1
* └── s3d2
* └── s3d3
*/
TEST_F_FORK(layout1_bind, no_restriction)
{
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s2d1, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s2d1, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s2d2, O_RDONLY));
ASSERT_EQ(0, test_open(file1_s2d2, O_RDONLY));
ASSERT_EQ(ENOENT, test_open(dir_s2d3, O_RDONLY));
ASSERT_EQ(ENOENT, test_open(file1_s2d3, O_RDONLY));
ASSERT_EQ(0, test_open(bind_dir_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(bind_file1_s1d3, O_RDONLY));
ASSERT_EQ(0, test_open(dir_s3d1, O_RDONLY));
}
TEST_F_FORK(layout1_bind, same_content_same_file)
{
/*
* Sets access right on parent directories of both source and
* destination mount points.
*/
const struct rule layer1_parent[] = {
{
.path = dir_s1d1,
.access = ACCESS_RO,
},
{
.path = dir_s2d1,
.access = ACCESS_RW,
},
{},
};
/*
* Sets access rights on the same bind-mounted directories. The result
* should be ACCESS_RW for both directories, but not both hierarchies
* because of the first layer.
*/
const struct rule layer2_mount_point[] = {
{
.path = dir_s1d2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = dir_s2d2,
.access = ACCESS_RW,
},
{},
};
/* Only allow read-access to the s1d3 hierarchies. */
const struct rule layer3_source[] = {
{
.path = dir_s1d3,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{},
};
/* Removes all access rights. */
const struct rule layer4_destination[] = {
{
.path = bind_file1_s1d3,
.access = LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
int ruleset_fd;
/* Sets rules for the parent directories. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer1_parent);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks source hierarchy. */
ASSERT_EQ(0, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(0, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* Checks destination hierarchy. */
ASSERT_EQ(0, test_open(file1_s2d1, O_RDWR));
ASSERT_EQ(0, test_open(dir_s2d1, O_RDONLY | O_DIRECTORY));
ASSERT_EQ(0, test_open(file1_s2d2, O_RDWR));
ASSERT_EQ(0, test_open(dir_s2d2, O_RDONLY | O_DIRECTORY));
/* Sets rules for the mount points. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer2_mount_point);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks source hierarchy. */
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
/* Checks destination hierarchy. */
ASSERT_EQ(EACCES, test_open(file1_s2d1, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s2d1, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s2d1, O_RDONLY | O_DIRECTORY));
ASSERT_EQ(0, test_open(file1_s2d2, O_RDWR));
ASSERT_EQ(0, test_open(dir_s2d2, O_RDONLY | O_DIRECTORY));
ASSERT_EQ(0, test_open(bind_dir_s1d3, O_RDONLY | O_DIRECTORY));
/* Sets a (shared) rule only on the source. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer3_source);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks source hierarchy. */
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
/* Checks destination hierarchy. */
ASSERT_EQ(EACCES, test_open(file1_s2d2, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s2d2, O_WRONLY));
ASSERT_EQ(EACCES, test_open(dir_s2d2, O_RDONLY | O_DIRECTORY));
ASSERT_EQ(0, test_open(bind_file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(bind_file1_s1d3, O_WRONLY));
ASSERT_EQ(EACCES, test_open(bind_dir_s1d3, O_RDONLY | O_DIRECTORY));
/* Sets a (shared) rule only on the destination. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer4_destination);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks source hierarchy. */
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
/* Checks destination hierarchy. */
ASSERT_EQ(EACCES, test_open(bind_file1_s1d3, O_RDONLY));
ASSERT_EQ(EACCES, test_open(bind_file1_s1d3, O_WRONLY));
}
TEST_F_FORK(layout1_bind, reparent_cross_mount)
{
const struct rule layer1[] = {
{
/* dir_s2d1 is beneath the dir_s2d2 mount point. */
.path = dir_s2d1,
.access = LANDLOCK_ACCESS_FS_REFER,
},
{
.path = bind_dir_s1d3,
.access = LANDLOCK_ACCESS_FS_EXECUTE,
},
{},
};
int ruleset_fd = create_ruleset(
_metadata,
LANDLOCK_ACCESS_FS_REFER | LANDLOCK_ACCESS_FS_EXECUTE, layer1);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks basic denied move. */
ASSERT_EQ(-1, rename(file1_s1d1, file1_s1d2));
ASSERT_EQ(EXDEV, errno);
/* Checks real cross-mount move (Landlock is not involved). */
ASSERT_EQ(-1, rename(file1_s2d1, file1_s2d2));
ASSERT_EQ(EXDEV, errno);
/* Checks move that will give more accesses. */
ASSERT_EQ(-1, rename(file1_s2d2, bind_file1_s1d3));
ASSERT_EQ(EXDEV, errno);
/* Checks legitimate downgrade move. */
ASSERT_EQ(0, rename(bind_file1_s1d3, file1_s2d2));
}
#define LOWER_BASE TMP_DIR "/lower"
#define LOWER_DATA LOWER_BASE "/data"
static const char lower_fl1[] = LOWER_DATA "/fl1";
static const char lower_dl1[] = LOWER_DATA "/dl1";
static const char lower_dl1_fl2[] = LOWER_DATA "/dl1/fl2";
static const char lower_fo1[] = LOWER_DATA "/fo1";
static const char lower_do1[] = LOWER_DATA "/do1";
static const char lower_do1_fo2[] = LOWER_DATA "/do1/fo2";
static const char lower_do1_fl3[] = LOWER_DATA "/do1/fl3";
static const char (*lower_base_files[])[] = {
&lower_fl1,
&lower_fo1,
NULL,
};
static const char (*lower_base_directories[])[] = {
&lower_dl1,
&lower_do1,
NULL,
};
static const char (*lower_sub_files[])[] = {
&lower_dl1_fl2,
&lower_do1_fo2,
&lower_do1_fl3,
NULL,
};
#define UPPER_BASE TMP_DIR "/upper"
#define UPPER_DATA UPPER_BASE "/data"
#define UPPER_WORK UPPER_BASE "/work"
static const char upper_fu1[] = UPPER_DATA "/fu1";
static const char upper_du1[] = UPPER_DATA "/du1";
static const char upper_du1_fu2[] = UPPER_DATA "/du1/fu2";
static const char upper_fo1[] = UPPER_DATA "/fo1";
static const char upper_do1[] = UPPER_DATA "/do1";
static const char upper_do1_fo2[] = UPPER_DATA "/do1/fo2";
static const char upper_do1_fu3[] = UPPER_DATA "/do1/fu3";
static const char (*upper_base_files[])[] = {
&upper_fu1,
&upper_fo1,
NULL,
};
static const char (*upper_base_directories[])[] = {
&upper_du1,
&upper_do1,
NULL,
};
static const char (*upper_sub_files[])[] = {
&upper_du1_fu2,
&upper_do1_fo2,
&upper_do1_fu3,
NULL,
};
#define MERGE_BASE TMP_DIR "/merge"
#define MERGE_DATA MERGE_BASE "/data"
static const char merge_fl1[] = MERGE_DATA "/fl1";
static const char merge_dl1[] = MERGE_DATA "/dl1";
static const char merge_dl1_fl2[] = MERGE_DATA "/dl1/fl2";
static const char merge_fu1[] = MERGE_DATA "/fu1";
static const char merge_du1[] = MERGE_DATA "/du1";
static const char merge_du1_fu2[] = MERGE_DATA "/du1/fu2";
static const char merge_fo1[] = MERGE_DATA "/fo1";
static const char merge_do1[] = MERGE_DATA "/do1";
static const char merge_do1_fo2[] = MERGE_DATA "/do1/fo2";
static const char merge_do1_fl3[] = MERGE_DATA "/do1/fl3";
static const char merge_do1_fu3[] = MERGE_DATA "/do1/fu3";
static const char (*merge_base_files[])[] = {
&merge_fl1,
&merge_fu1,
&merge_fo1,
NULL,
};
static const char (*merge_base_directories[])[] = {
&merge_dl1,
&merge_du1,
&merge_do1,
NULL,
};
static const char (*merge_sub_files[])[] = {
&merge_dl1_fl2, &merge_du1_fu2, &merge_do1_fo2,
&merge_do1_fl3, &merge_do1_fu3, NULL,
};
/*
* layout2_overlay hierarchy:
*
* tmp
* ├── lower
* │   └── data
* │   ├── dl1
* │   │   └── fl2
* │   ├── do1
* │   │   ├── fl3
* │   │   └── fo2
* │   ├── fl1
* │   └── fo1
* ├── merge
* │   └── data
* │   ├── dl1
* │   │   └── fl2
* │   ├── do1
* │   │   ├── fl3
* │   │   ├── fo2
* │   │   └── fu3
* │   ├── du1
* │   │   └── fu2
* │   ├── fl1
* │   ├── fo1
* │   └── fu1
* └── upper
* ├── data
* │   ├── do1
* │   │   ├── fo2
* │   │   └── fu3
* │   ├── du1
* │   │   └── fu2
* │   ├── fo1
* │   └── fu1
* └── work
* └── work
*/
/* clang-format off */
FIXTURE(layout2_overlay) {};
/* clang-format on */
FIXTURE_SETUP(layout2_overlay)
{
if (!supports_overlayfs())
SKIP(return, "overlayfs is not supported");
prepare_layout(_metadata);
create_directory(_metadata, LOWER_BASE);
set_cap(_metadata, CAP_SYS_ADMIN);
/* Creates tmpfs mount points to get deterministic overlayfs. */
ASSERT_EQ(0, mount("tmp", LOWER_BASE, "tmpfs", 0, "size=4m,mode=700"));
clear_cap(_metadata, CAP_SYS_ADMIN);
create_file(_metadata, lower_fl1);
create_file(_metadata, lower_dl1_fl2);
create_file(_metadata, lower_fo1);
create_file(_metadata, lower_do1_fo2);
create_file(_metadata, lower_do1_fl3);
create_directory(_metadata, UPPER_BASE);
set_cap(_metadata, CAP_SYS_ADMIN);
ASSERT_EQ(0, mount("tmp", UPPER_BASE, "tmpfs", 0, "size=4m,mode=700"));
clear_cap(_metadata, CAP_SYS_ADMIN);
create_file(_metadata, upper_fu1);
create_file(_metadata, upper_du1_fu2);
create_file(_metadata, upper_fo1);
create_file(_metadata, upper_do1_fo2);
create_file(_metadata, upper_do1_fu3);
ASSERT_EQ(0, mkdir(UPPER_WORK, 0700));
create_directory(_metadata, MERGE_DATA);
set_cap(_metadata, CAP_SYS_ADMIN);
set_cap(_metadata, CAP_DAC_OVERRIDE);
ASSERT_EQ(0, mount("overlay", MERGE_DATA, "overlay", 0,
"lowerdir=" LOWER_DATA ",upperdir=" UPPER_DATA
",workdir=" UPPER_WORK));
clear_cap(_metadata, CAP_DAC_OVERRIDE);
clear_cap(_metadata, CAP_SYS_ADMIN);
}
FIXTURE_TEARDOWN(layout2_overlay)
{
if (!supports_overlayfs())
SKIP(return, "overlayfs is not supported");
EXPECT_EQ(0, remove_path(lower_do1_fl3));
EXPECT_EQ(0, remove_path(lower_dl1_fl2));
EXPECT_EQ(0, remove_path(lower_fl1));
EXPECT_EQ(0, remove_path(lower_do1_fo2));
EXPECT_EQ(0, remove_path(lower_fo1));
set_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, umount(LOWER_BASE));
clear_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, remove_path(LOWER_BASE));
EXPECT_EQ(0, remove_path(upper_do1_fu3));
EXPECT_EQ(0, remove_path(upper_du1_fu2));
EXPECT_EQ(0, remove_path(upper_fu1));
EXPECT_EQ(0, remove_path(upper_do1_fo2));
EXPECT_EQ(0, remove_path(upper_fo1));
EXPECT_EQ(0, remove_path(UPPER_WORK "/work"));
set_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, umount(UPPER_BASE));
clear_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, remove_path(UPPER_BASE));
set_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, umount(MERGE_DATA));
clear_cap(_metadata, CAP_SYS_ADMIN);
EXPECT_EQ(0, remove_path(MERGE_DATA));
cleanup_layout(_metadata);
}
TEST_F_FORK(layout2_overlay, no_restriction)
{
if (!supports_overlayfs())
SKIP(return, "overlayfs is not supported");
ASSERT_EQ(0, test_open(lower_fl1, O_RDONLY));
ASSERT_EQ(0, test_open(lower_dl1, O_RDONLY));
ASSERT_EQ(0, test_open(lower_dl1_fl2, O_RDONLY));
ASSERT_EQ(0, test_open(lower_fo1, O_RDONLY));
ASSERT_EQ(0, test_open(lower_do1, O_RDONLY));
ASSERT_EQ(0, test_open(lower_do1_fo2, O_RDONLY));
ASSERT_EQ(0, test_open(lower_do1_fl3, O_RDONLY));
ASSERT_EQ(0, test_open(upper_fu1, O_RDONLY));
ASSERT_EQ(0, test_open(upper_du1, O_RDONLY));
ASSERT_EQ(0, test_open(upper_du1_fu2, O_RDONLY));
ASSERT_EQ(0, test_open(upper_fo1, O_RDONLY));
ASSERT_EQ(0, test_open(upper_do1, O_RDONLY));
ASSERT_EQ(0, test_open(upper_do1_fo2, O_RDONLY));
ASSERT_EQ(0, test_open(upper_do1_fu3, O_RDONLY));
ASSERT_EQ(0, test_open(merge_fl1, O_RDONLY));
ASSERT_EQ(0, test_open(merge_dl1, O_RDONLY));
ASSERT_EQ(0, test_open(merge_dl1_fl2, O_RDONLY));
ASSERT_EQ(0, test_open(merge_fu1, O_RDONLY));
ASSERT_EQ(0, test_open(merge_du1, O_RDONLY));
ASSERT_EQ(0, test_open(merge_du1_fu2, O_RDONLY));
ASSERT_EQ(0, test_open(merge_fo1, O_RDONLY));
ASSERT_EQ(0, test_open(merge_do1, O_RDONLY));
ASSERT_EQ(0, test_open(merge_do1_fo2, O_RDONLY));
ASSERT_EQ(0, test_open(merge_do1_fl3, O_RDONLY));
ASSERT_EQ(0, test_open(merge_do1_fu3, O_RDONLY));
}
#define for_each_path(path_list, path_entry, i) \
for (i = 0, path_entry = *path_list[i]; path_list[i]; \
path_entry = *path_list[++i])
TEST_F_FORK(layout2_overlay, same_content_different_file)
{
/* Sets access right on parent directories of both layers. */
const struct rule layer1_base[] = {
{
.path = LOWER_BASE,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = UPPER_BASE,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = MERGE_BASE,
.access = ACCESS_RW,
},
{},
};
const struct rule layer2_data[] = {
{
.path = LOWER_DATA,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = UPPER_DATA,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = MERGE_DATA,
.access = ACCESS_RW,
},
{},
};
/* Sets access right on directories inside both layers. */
const struct rule layer3_subdirs[] = {
{
.path = lower_dl1,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = lower_do1,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = upper_du1,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = upper_do1,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = merge_dl1,
.access = ACCESS_RW,
},
{
.path = merge_du1,
.access = ACCESS_RW,
},
{
.path = merge_do1,
.access = ACCESS_RW,
},
{},
};
/* Tighten access rights to the files. */
const struct rule layer4_files[] = {
{
.path = lower_dl1_fl2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = lower_do1_fo2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = lower_do1_fl3,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = upper_du1_fu2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = upper_do1_fo2,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = upper_do1_fu3,
.access = LANDLOCK_ACCESS_FS_READ_FILE,
},
{
.path = merge_dl1_fl2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{
.path = merge_du1_fu2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{
.path = merge_do1_fo2,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{
.path = merge_do1_fl3,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{
.path = merge_do1_fu3,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
const struct rule layer5_merge_only[] = {
{
.path = MERGE_DATA,
.access = LANDLOCK_ACCESS_FS_READ_FILE |
LANDLOCK_ACCESS_FS_WRITE_FILE,
},
{},
};
int ruleset_fd;
size_t i;
const char *path_entry;
if (!supports_overlayfs())
SKIP(return, "overlayfs is not supported");
/* Sets rules on base directories (i.e. outside overlay scope). */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer1_base);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks lower layer. */
for_each_path(lower_base_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY));
ASSERT_EQ(EACCES, test_open(path_entry, O_WRONLY));
}
for_each_path(lower_base_directories, path_entry, i) {
ASSERT_EQ(EACCES,
test_open(path_entry, O_RDONLY | O_DIRECTORY));
}
for_each_path(lower_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY));
ASSERT_EQ(EACCES, test_open(path_entry, O_WRONLY));
}
/* Checks upper layer. */
for_each_path(upper_base_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY));
ASSERT_EQ(EACCES, test_open(path_entry, O_WRONLY));
}
for_each_path(upper_base_directories, path_entry, i) {
ASSERT_EQ(EACCES,
test_open(path_entry, O_RDONLY | O_DIRECTORY));
}
for_each_path(upper_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY));
ASSERT_EQ(EACCES, test_open(path_entry, O_WRONLY));
}
/*
* Checks that access rights are independent from the lower and upper
* layers: write access to upper files viewed through the merge point
* is still allowed, and write access to lower file viewed (and copied)
* through the merge point is still allowed.
*/
for_each_path(merge_base_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDWR));
}
for_each_path(merge_base_directories, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY | O_DIRECTORY));
}
for_each_path(merge_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDWR));
}
/* Sets rules on data directories (i.e. inside overlay scope). */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer2_data);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks merge. */
for_each_path(merge_base_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDWR));
}
for_each_path(merge_base_directories, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY | O_DIRECTORY));
}
for_each_path(merge_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDWR));
}
/* Same checks with tighter rules. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer3_subdirs);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks changes for lower layer. */
for_each_path(lower_base_files, path_entry, i) {
ASSERT_EQ(EACCES, test_open(path_entry, O_RDONLY));
}
/* Checks changes for upper layer. */
for_each_path(upper_base_files, path_entry, i) {
ASSERT_EQ(EACCES, test_open(path_entry, O_RDONLY));
}
/* Checks all merge accesses. */
for_each_path(merge_base_files, path_entry, i) {
ASSERT_EQ(EACCES, test_open(path_entry, O_RDWR));
}
for_each_path(merge_base_directories, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY | O_DIRECTORY));
}
for_each_path(merge_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDWR));
}
/* Sets rules directly on overlayed files. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer4_files);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks unchanged accesses on lower layer. */
for_each_path(lower_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY));
ASSERT_EQ(EACCES, test_open(path_entry, O_WRONLY));
}
/* Checks unchanged accesses on upper layer. */
for_each_path(upper_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDONLY));
ASSERT_EQ(EACCES, test_open(path_entry, O_WRONLY));
}
/* Checks all merge accesses. */
for_each_path(merge_base_files, path_entry, i) {
ASSERT_EQ(EACCES, test_open(path_entry, O_RDWR));
}
for_each_path(merge_base_directories, path_entry, i) {
ASSERT_EQ(EACCES,
test_open(path_entry, O_RDONLY | O_DIRECTORY));
}
for_each_path(merge_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDWR));
}
/* Only allowes access to the merge hierarchy. */
ruleset_fd = create_ruleset(_metadata, ACCESS_RW, layer5_merge_only);
ASSERT_LE(0, ruleset_fd);
enforce_ruleset(_metadata, ruleset_fd);
ASSERT_EQ(0, close(ruleset_fd));
/* Checks new accesses on lower layer. */
for_each_path(lower_sub_files, path_entry, i) {
ASSERT_EQ(EACCES, test_open(path_entry, O_RDONLY));
}
/* Checks new accesses on upper layer. */
for_each_path(upper_sub_files, path_entry, i) {
ASSERT_EQ(EACCES, test_open(path_entry, O_RDONLY));
}
/* Checks all merge accesses. */
for_each_path(merge_base_files, path_entry, i) {
ASSERT_EQ(EACCES, test_open(path_entry, O_RDWR));
}
for_each_path(merge_base_directories, path_entry, i) {
ASSERT_EQ(EACCES,
test_open(path_entry, O_RDONLY | O_DIRECTORY));
}
for_each_path(merge_sub_files, path_entry, i) {
ASSERT_EQ(0, test_open(path_entry, O_RDWR));
}
}
TEST_HARNESS_MAIN