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android-kvm / linux / 957bfa31f1d93ba7ea9fda2a401b0f3c79129d5e / . / tools / testing / selftests / landlock / fs_test.c
blob: b6c4be3faf7a9801774d660893065ed4701dd17f [file] [log] [blame]
// 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