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-rw-r--r--tools/testing/selftests/landlock/.gitignore2
-rw-r--r--tools/testing/selftests/landlock/Makefile23
-rw-r--r--tools/testing/selftests/landlock/base_test.c329
-rw-r--r--tools/testing/selftests/landlock/common.h258
-rw-r--r--tools/testing/selftests/landlock/config10
-rw-r--r--tools/testing/selftests/landlock/config.um1
-rw-r--r--tools/testing/selftests/landlock/fs_test.c4765
-rw-r--r--tools/testing/selftests/landlock/ptrace_test.c438
-rw-r--r--tools/testing/selftests/landlock/true.c5
9 files changed, 5831 insertions, 0 deletions
diff --git a/tools/testing/selftests/landlock/.gitignore b/tools/testing/selftests/landlock/.gitignore
new file mode 100644
index 0000000000..470203a7cd
--- /dev/null
+++ b/tools/testing/selftests/landlock/.gitignore
@@ -0,0 +1,2 @@
+/*_test
+/true
diff --git a/tools/testing/selftests/landlock/Makefile b/tools/testing/selftests/landlock/Makefile
new file mode 100644
index 0000000000..348e2dbdb4
--- /dev/null
+++ b/tools/testing/selftests/landlock/Makefile
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# First run: make -C ../../../.. headers_install
+
+CFLAGS += -Wall -O2 $(KHDR_INCLUDES)
+
+LOCAL_HDRS += common.h
+
+src_test := $(wildcard *_test.c)
+
+TEST_GEN_PROGS := $(src_test:.c=)
+
+TEST_GEN_PROGS_EXTENDED := true
+
+# Short targets:
+$(TEST_GEN_PROGS): LDLIBS += -lcap
+$(TEST_GEN_PROGS_EXTENDED): LDFLAGS += -static
+
+include ../lib.mk
+
+# Targets with $(OUTPUT)/ prefix:
+$(TEST_GEN_PROGS): LDLIBS += -lcap
+$(TEST_GEN_PROGS_EXTENDED): LDFLAGS += -static
diff --git a/tools/testing/selftests/landlock/base_test.c b/tools/testing/selftests/landlock/base_test.c
new file mode 100644
index 0000000000..792c3f0a59
--- /dev/null
+++ b/tools/testing/selftests/landlock/base_test.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Landlock tests - Common user space base
+ *
+ * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2019-2020 ANSSI
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/landlock.h>
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include "common.h"
+
+#ifndef O_PATH
+#define O_PATH 010000000
+#endif
+
+TEST(inconsistent_attr)
+{
+ const long page_size = sysconf(_SC_PAGESIZE);
+ char *const buf = malloc(page_size + 1);
+ struct landlock_ruleset_attr *const ruleset_attr = (void *)buf;
+
+ ASSERT_NE(NULL, buf);
+
+ /* Checks copy_from_user(). */
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, 0, 0));
+ /* The size if less than sizeof(struct landlock_attr_enforce). */
+ ASSERT_EQ(EINVAL, errno);
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, 1, 0));
+ ASSERT_EQ(EINVAL, errno);
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, 7, 0));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(NULL, 1, 0));
+ /* The size if less than sizeof(struct landlock_attr_enforce). */
+ ASSERT_EQ(EFAULT, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(
+ NULL, sizeof(struct landlock_ruleset_attr), 0));
+ ASSERT_EQ(EFAULT, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size + 1, 0));
+ ASSERT_EQ(E2BIG, errno);
+
+ /* Checks minimal valid attribute size. */
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, 8, 0));
+ ASSERT_EQ(ENOMSG, errno);
+ ASSERT_EQ(-1, landlock_create_ruleset(
+ ruleset_attr,
+ sizeof(struct landlock_ruleset_attr), 0));
+ ASSERT_EQ(ENOMSG, errno);
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size, 0));
+ ASSERT_EQ(ENOMSG, errno);
+
+ /* Checks non-zero value. */
+ buf[page_size - 2] = '.';
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size, 0));
+ ASSERT_EQ(E2BIG, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(ruleset_attr, page_size + 1, 0));
+ ASSERT_EQ(E2BIG, errno);
+
+ free(buf);
+}
+
+TEST(abi_version)
+{
+ const struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE,
+ };
+ ASSERT_EQ(3, landlock_create_ruleset(NULL, 0,
+ LANDLOCK_CREATE_RULESET_VERSION));
+
+ ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 0,
+ LANDLOCK_CREATE_RULESET_VERSION));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(NULL, sizeof(ruleset_attr),
+ LANDLOCK_CREATE_RULESET_VERSION));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(-1,
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr),
+ LANDLOCK_CREATE_RULESET_VERSION));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(NULL, 0,
+ LANDLOCK_CREATE_RULESET_VERSION |
+ 1 << 31));
+ ASSERT_EQ(EINVAL, errno);
+}
+
+/* Tests ordering of syscall argument checks. */
+TEST(create_ruleset_checks_ordering)
+{
+ const int last_flag = LANDLOCK_CREATE_RULESET_VERSION;
+ const int invalid_flag = last_flag << 1;
+ int ruleset_fd;
+ const struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE,
+ };
+
+ /* Checks priority for invalid flags. */
+ ASSERT_EQ(-1, landlock_create_ruleset(NULL, 0, invalid_flag));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 0, invalid_flag));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(-1, landlock_create_ruleset(NULL, sizeof(ruleset_attr),
+ invalid_flag));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(-1,
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr),
+ invalid_flag));
+ ASSERT_EQ(EINVAL, errno);
+
+ /* Checks too big ruleset_attr size. */
+ ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, -1, 0));
+ ASSERT_EQ(E2BIG, errno);
+
+ /* Checks too small ruleset_attr size. */
+ ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 0, 0));
+ ASSERT_EQ(EINVAL, errno);
+ ASSERT_EQ(-1, landlock_create_ruleset(&ruleset_attr, 1, 0));
+ ASSERT_EQ(EINVAL, errno);
+
+ /* Checks valid call. */
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+}
+
+/* Tests ordering of syscall argument checks. */
+TEST(add_rule_checks_ordering)
+{
+ const struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE,
+ };
+ struct landlock_path_beneath_attr path_beneath_attr = {
+ .allowed_access = LANDLOCK_ACCESS_FS_EXECUTE,
+ .parent_fd = -1,
+ };
+ const int ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Checks invalid flags. */
+ ASSERT_EQ(-1, landlock_add_rule(-1, 0, NULL, 1));
+ ASSERT_EQ(EINVAL, errno);
+
+ /* Checks invalid ruleset FD. */
+ ASSERT_EQ(-1, landlock_add_rule(-1, 0, NULL, 0));
+ ASSERT_EQ(EBADF, errno);
+
+ /* Checks invalid rule type. */
+ ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, 0, NULL, 0));
+ ASSERT_EQ(EINVAL, errno);
+
+ /* Checks invalid rule attr. */
+ ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ NULL, 0));
+ ASSERT_EQ(EFAULT, errno);
+
+ /* Checks invalid path_beneath.parent_fd. */
+ ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &path_beneath_attr, 0));
+ ASSERT_EQ(EBADF, errno);
+
+ /* Checks valid call. */
+ path_beneath_attr.parent_fd =
+ open("/tmp", O_PATH | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
+ ASSERT_LE(0, path_beneath_attr.parent_fd);
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &path_beneath_attr, 0));
+ ASSERT_EQ(0, close(path_beneath_attr.parent_fd));
+ ASSERT_EQ(0, close(ruleset_fd));
+}
+
+/* Tests ordering of syscall argument and permission checks. */
+TEST(restrict_self_checks_ordering)
+{
+ const struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE,
+ };
+ struct landlock_path_beneath_attr path_beneath_attr = {
+ .allowed_access = LANDLOCK_ACCESS_FS_EXECUTE,
+ .parent_fd = -1,
+ };
+ const int ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+
+ ASSERT_LE(0, ruleset_fd);
+ path_beneath_attr.parent_fd =
+ open("/tmp", O_PATH | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
+ ASSERT_LE(0, path_beneath_attr.parent_fd);
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &path_beneath_attr, 0));
+ ASSERT_EQ(0, close(path_beneath_attr.parent_fd));
+
+ /* Checks unprivileged enforcement without no_new_privs. */
+ drop_caps(_metadata);
+ ASSERT_EQ(-1, landlock_restrict_self(-1, -1));
+ ASSERT_EQ(EPERM, errno);
+ ASSERT_EQ(-1, landlock_restrict_self(-1, 0));
+ ASSERT_EQ(EPERM, errno);
+ ASSERT_EQ(-1, landlock_restrict_self(ruleset_fd, 0));
+ ASSERT_EQ(EPERM, errno);
+
+ ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
+
+ /* Checks invalid flags. */
+ ASSERT_EQ(-1, landlock_restrict_self(-1, -1));
+ ASSERT_EQ(EINVAL, errno);
+
+ /* Checks invalid ruleset FD. */
+ ASSERT_EQ(-1, landlock_restrict_self(-1, 0));
+ ASSERT_EQ(EBADF, errno);
+
+ /* Checks valid call. */
+ ASSERT_EQ(0, landlock_restrict_self(ruleset_fd, 0));
+ ASSERT_EQ(0, close(ruleset_fd));
+}
+
+TEST(ruleset_fd_io)
+{
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE,
+ };
+ int ruleset_fd;
+ char buf;
+
+ drop_caps(_metadata);
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ ASSERT_EQ(-1, write(ruleset_fd, ".", 1));
+ ASSERT_EQ(EINVAL, errno);
+ ASSERT_EQ(-1, read(ruleset_fd, &buf, 1));
+ ASSERT_EQ(EINVAL, errno);
+
+ ASSERT_EQ(0, close(ruleset_fd));
+}
+
+/* Tests enforcement of a ruleset FD transferred through a UNIX socket. */
+TEST(ruleset_fd_transfer)
+{
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_READ_DIR,
+ };
+ struct landlock_path_beneath_attr path_beneath_attr = {
+ .allowed_access = LANDLOCK_ACCESS_FS_READ_DIR,
+ };
+ int ruleset_fd_tx, dir_fd;
+ int socket_fds[2];
+ pid_t child;
+ int status;
+
+ drop_caps(_metadata);
+
+ /* Creates a test ruleset with a simple rule. */
+ ruleset_fd_tx =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd_tx);
+ path_beneath_attr.parent_fd =
+ open("/tmp", O_PATH | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
+ ASSERT_LE(0, path_beneath_attr.parent_fd);
+ ASSERT_EQ(0,
+ landlock_add_rule(ruleset_fd_tx, LANDLOCK_RULE_PATH_BENEATH,
+ &path_beneath_attr, 0));
+ ASSERT_EQ(0, close(path_beneath_attr.parent_fd));
+
+ /* Sends the ruleset FD over a socketpair and then close it. */
+ ASSERT_EQ(0, socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0,
+ socket_fds));
+ ASSERT_EQ(0, send_fd(socket_fds[0], ruleset_fd_tx));
+ ASSERT_EQ(0, close(socket_fds[0]));
+ ASSERT_EQ(0, close(ruleset_fd_tx));
+
+ child = fork();
+ ASSERT_LE(0, child);
+ if (child == 0) {
+ const int ruleset_fd_rx = recv_fd(socket_fds[1]);
+
+ ASSERT_LE(0, ruleset_fd_rx);
+ ASSERT_EQ(0, close(socket_fds[1]));
+
+ /* Enforces the received ruleset on the child. */
+ ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
+ ASSERT_EQ(0, landlock_restrict_self(ruleset_fd_rx, 0));
+ ASSERT_EQ(0, close(ruleset_fd_rx));
+
+ /* Checks that the ruleset enforcement. */
+ ASSERT_EQ(-1, open("/", O_RDONLY | O_DIRECTORY | O_CLOEXEC));
+ ASSERT_EQ(EACCES, errno);
+ dir_fd = open("/tmp", O_RDONLY | O_DIRECTORY | O_CLOEXEC);
+ ASSERT_LE(0, dir_fd);
+ ASSERT_EQ(0, close(dir_fd));
+ _exit(_metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
+ return;
+ }
+
+ ASSERT_EQ(0, close(socket_fds[1]));
+
+ /* Checks that the parent is unrestricted. */
+ dir_fd = open("/", O_RDONLY | O_DIRECTORY | O_CLOEXEC);
+ ASSERT_LE(0, dir_fd);
+ ASSERT_EQ(0, close(dir_fd));
+ dir_fd = open("/tmp", O_RDONLY | O_DIRECTORY | O_CLOEXEC);
+ ASSERT_LE(0, dir_fd);
+ ASSERT_EQ(0, close(dir_fd));
+
+ ASSERT_EQ(child, waitpid(child, &status, 0));
+ ASSERT_EQ(1, WIFEXITED(status));
+ ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status));
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/landlock/common.h b/tools/testing/selftests/landlock/common.h
new file mode 100644
index 0000000000..d7987ae8d7
--- /dev/null
+++ b/tools/testing/selftests/landlock/common.h
@@ -0,0 +1,258 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Landlock test helpers
+ *
+ * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2019-2020 ANSSI
+ * Copyright © 2021 Microsoft Corporation
+ */
+
+#include <errno.h>
+#include <linux/landlock.h>
+#include <sys/capability.h>
+#include <sys/socket.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "../kselftest_harness.h"
+
+#ifndef __maybe_unused
+#define __maybe_unused __attribute__((__unused__))
+#endif
+
+/*
+ * TEST_F_FORK() is useful when a test drop privileges but the corresponding
+ * FIXTURE_TEARDOWN() requires them (e.g. to remove files from a directory
+ * where write actions are denied). For convenience, FIXTURE_TEARDOWN() is
+ * also called when the test failed, but not when FIXTURE_SETUP() failed. For
+ * this to be possible, we must not call abort() but instead exit smoothly
+ * (hence the step print).
+ */
+/* clang-format off */
+#define TEST_F_FORK(fixture_name, test_name) \
+ static void fixture_name##_##test_name##_child( \
+ struct __test_metadata *_metadata, \
+ FIXTURE_DATA(fixture_name) *self, \
+ const FIXTURE_VARIANT(fixture_name) *variant); \
+ TEST_F(fixture_name, test_name) \
+ { \
+ int status; \
+ const pid_t child = fork(); \
+ if (child < 0) \
+ abort(); \
+ if (child == 0) { \
+ _metadata->no_print = 1; \
+ fixture_name##_##test_name##_child(_metadata, self, variant); \
+ if (_metadata->skip) \
+ _exit(255); \
+ if (_metadata->passed) \
+ _exit(0); \
+ _exit(_metadata->step); \
+ } \
+ if (child != waitpid(child, &status, 0)) \
+ abort(); \
+ if (WIFSIGNALED(status) || !WIFEXITED(status)) { \
+ _metadata->passed = 0; \
+ _metadata->step = 1; \
+ return; \
+ } \
+ switch (WEXITSTATUS(status)) { \
+ case 0: \
+ _metadata->passed = 1; \
+ break; \
+ case 255: \
+ _metadata->passed = 1; \
+ _metadata->skip = 1; \
+ break; \
+ default: \
+ _metadata->passed = 0; \
+ _metadata->step = WEXITSTATUS(status); \
+ break; \
+ } \
+ } \
+ static void fixture_name##_##test_name##_child( \
+ struct __test_metadata __attribute__((unused)) *_metadata, \
+ FIXTURE_DATA(fixture_name) __attribute__((unused)) *self, \
+ const FIXTURE_VARIANT(fixture_name) \
+ __attribute__((unused)) *variant)
+/* clang-format on */
+
+#ifndef landlock_create_ruleset
+static inline int
+landlock_create_ruleset(const struct landlock_ruleset_attr *const attr,
+ const size_t size, const __u32 flags)
+{
+ return syscall(__NR_landlock_create_ruleset, attr, size, flags);
+}
+#endif
+
+#ifndef landlock_add_rule
+static inline int landlock_add_rule(const int ruleset_fd,
+ const enum landlock_rule_type rule_type,
+ const void *const rule_attr,
+ const __u32 flags)
+{
+ return syscall(__NR_landlock_add_rule, ruleset_fd, rule_type, rule_attr,
+ flags);
+}
+#endif
+
+#ifndef landlock_restrict_self
+static inline int landlock_restrict_self(const int ruleset_fd,
+ const __u32 flags)
+{
+ return syscall(__NR_landlock_restrict_self, ruleset_fd, flags);
+}
+#endif
+
+static void _init_caps(struct __test_metadata *const _metadata, bool drop_all)
+{
+ cap_t cap_p;
+ /* Only these three capabilities are useful for the tests. */
+ const cap_value_t caps[] = {
+ CAP_DAC_OVERRIDE,
+ CAP_MKNOD,
+ CAP_SYS_ADMIN,
+ CAP_SYS_CHROOT,
+ };
+
+ cap_p = cap_get_proc();
+ EXPECT_NE(NULL, cap_p)
+ {
+ TH_LOG("Failed to cap_get_proc: %s", strerror(errno));
+ }
+ EXPECT_NE(-1, cap_clear(cap_p))
+ {
+ TH_LOG("Failed to cap_clear: %s", strerror(errno));
+ }
+ if (!drop_all) {
+ EXPECT_NE(-1, cap_set_flag(cap_p, CAP_PERMITTED,
+ ARRAY_SIZE(caps), caps, CAP_SET))
+ {
+ TH_LOG("Failed to cap_set_flag: %s", strerror(errno));
+ }
+ }
+ EXPECT_NE(-1, cap_set_proc(cap_p))
+ {
+ TH_LOG("Failed to cap_set_proc: %s", strerror(errno));
+ }
+ EXPECT_NE(-1, cap_free(cap_p))
+ {
+ TH_LOG("Failed to cap_free: %s", strerror(errno));
+ }
+}
+
+/* We cannot put such helpers in a library because of kselftest_harness.h . */
+static void __maybe_unused disable_caps(struct __test_metadata *const _metadata)
+{
+ _init_caps(_metadata, false);
+}
+
+static void __maybe_unused drop_caps(struct __test_metadata *const _metadata)
+{
+ _init_caps(_metadata, true);
+}
+
+static void _effective_cap(struct __test_metadata *const _metadata,
+ const cap_value_t caps, const cap_flag_value_t value)
+{
+ cap_t cap_p;
+
+ cap_p = cap_get_proc();
+ EXPECT_NE(NULL, cap_p)
+ {
+ TH_LOG("Failed to cap_get_proc: %s", strerror(errno));
+ }
+ EXPECT_NE(-1, cap_set_flag(cap_p, CAP_EFFECTIVE, 1, &caps, value))
+ {
+ TH_LOG("Failed to cap_set_flag: %s", strerror(errno));
+ }
+ EXPECT_NE(-1, cap_set_proc(cap_p))
+ {
+ TH_LOG("Failed to cap_set_proc: %s", strerror(errno));
+ }
+ EXPECT_NE(-1, cap_free(cap_p))
+ {
+ TH_LOG("Failed to cap_free: %s", strerror(errno));
+ }
+}
+
+static void __maybe_unused set_cap(struct __test_metadata *const _metadata,
+ const cap_value_t caps)
+{
+ _effective_cap(_metadata, caps, CAP_SET);
+}
+
+static void __maybe_unused clear_cap(struct __test_metadata *const _metadata,
+ const cap_value_t caps)
+{
+ _effective_cap(_metadata, caps, CAP_CLEAR);
+}
+
+/* Receives an FD from a UNIX socket. Returns the received FD, or -errno. */
+static int __maybe_unused recv_fd(int usock)
+{
+ int fd_rx;
+ union {
+ /* Aligned ancillary data buffer. */
+ char buf[CMSG_SPACE(sizeof(fd_rx))];
+ struct cmsghdr _align;
+ } cmsg_rx = {};
+ char data = '\0';
+ struct iovec io = {
+ .iov_base = &data,
+ .iov_len = sizeof(data),
+ };
+ struct msghdr msg = {
+ .msg_iov = &io,
+ .msg_iovlen = 1,
+ .msg_control = &cmsg_rx.buf,
+ .msg_controllen = sizeof(cmsg_rx.buf),
+ };
+ struct cmsghdr *cmsg;
+ int res;
+
+ res = recvmsg(usock, &msg, MSG_CMSG_CLOEXEC);
+ if (res < 0)
+ return -errno;
+
+ cmsg = CMSG_FIRSTHDR(&msg);
+ if (cmsg->cmsg_len != CMSG_LEN(sizeof(fd_rx)))
+ return -EIO;
+
+ memcpy(&fd_rx, CMSG_DATA(cmsg), sizeof(fd_rx));
+ return fd_rx;
+}
+
+/* Sends an FD on a UNIX socket. Returns 0 on success or -errno. */
+static int __maybe_unused send_fd(int usock, int fd_tx)
+{
+ union {
+ /* Aligned ancillary data buffer. */
+ char buf[CMSG_SPACE(sizeof(fd_tx))];
+ struct cmsghdr _align;
+ } cmsg_tx = {};
+ char data_tx = '.';
+ struct iovec io = {
+ .iov_base = &data_tx,
+ .iov_len = sizeof(data_tx),
+ };
+ struct msghdr msg = {
+ .msg_iov = &io,
+ .msg_iovlen = 1,
+ .msg_control = &cmsg_tx.buf,
+ .msg_controllen = sizeof(cmsg_tx.buf),
+ };
+ struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
+
+ cmsg->cmsg_len = CMSG_LEN(sizeof(fd_tx));
+ cmsg->cmsg_level = SOL_SOCKET;
+ cmsg->cmsg_type = SCM_RIGHTS;
+ memcpy(CMSG_DATA(cmsg), &fd_tx, sizeof(fd_tx));
+
+ if (sendmsg(usock, &msg, 0) < 0)
+ return -errno;
+ return 0;
+}
diff --git a/tools/testing/selftests/landlock/config b/tools/testing/selftests/landlock/config
new file mode 100644
index 0000000000..3dc9e438ea
--- /dev/null
+++ b/tools/testing/selftests/landlock/config
@@ -0,0 +1,10 @@
+CONFIG_CGROUPS=y
+CONFIG_CGROUP_SCHED=y
+CONFIG_OVERLAY_FS=y
+CONFIG_PROC_FS=y
+CONFIG_SECURITY=y
+CONFIG_SECURITY_LANDLOCK=y
+CONFIG_SHMEM=y
+CONFIG_SYSFS=y
+CONFIG_TMPFS=y
+CONFIG_TMPFS_XATTR=y
diff --git a/tools/testing/selftests/landlock/config.um b/tools/testing/selftests/landlock/config.um
new file mode 100644
index 0000000000..40937c0395
--- /dev/null
+++ b/tools/testing/selftests/landlock/config.um
@@ -0,0 +1 @@
+CONFIG_HOSTFS=y
diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
new file mode 100644
index 0000000000..251594306d
--- /dev/null
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -0,0 +1,4765 @@
+// 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 <linux/magic.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 <sys/vfs.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_filesystem(const char *const filesystem)
+{
+ char str[32];
+ int len;
+ bool res = true;
+ FILE *const inf = fopen("/proc/filesystems", "r");
+
+ /*
+ * Consider that the filesystem is supported if we cannot get the
+ * supported ones.
+ */
+ if (!inf)
+ return true;
+
+ /* filesystem can be null for bind mounts. */
+ if (!filesystem)
+ goto out;
+
+ len = snprintf(str, sizeof(str), "nodev\t%s\n", filesystem);
+ if (len >= sizeof(str))
+ /* Ignores too-long filesystem names. */
+ goto out;
+
+ res = fgrep(inf, str);
+
+out:
+ fclose(inf);
+ return res;
+}
+
+static bool cwd_matches_fs(unsigned int fs_magic)
+{
+ struct statfs statfs_buf;
+
+ if (!fs_magic)
+ return true;
+
+ if (statfs(".", &statfs_buf))
+ return true;
+
+ return statfs_buf.f_type == fs_magic;
+}
+
+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;
+}
+
+struct mnt_opt {
+ const char *const source;
+ const char *const type;
+ const unsigned long flags;
+ const char *const data;
+};
+
+const struct mnt_opt mnt_tmp = {
+ .type = "tmpfs",
+ .data = "size=4m,mode=700",
+};
+
+static int mount_opt(const struct mnt_opt *const mnt, const char *const target)
+{
+ return mount(mnt->source ?: mnt->type, target, mnt->type, mnt->flags,
+ mnt->data);
+}
+
+static void prepare_layout_opt(struct __test_metadata *const _metadata,
+ const struct mnt_opt *const mnt)
+{
+ 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 | CLONE_NEWCGROUP));
+ ASSERT_EQ(0, mount_opt(mnt, TMP_DIR))
+ {
+ TH_LOG("Failed to mount the %s filesystem: %s", mnt->type,
+ strerror(errno));
+ /*
+ * FIXTURE_TEARDOWN() is not called when FIXTURE_SETUP()
+ * failed, so we need to explicitly do a minimal cleanup to
+ * avoid cascading errors with other tests that don't depend on
+ * the same filesystem.
+ */
+ remove_path(TMP_DIR);
+ }
+ ASSERT_EQ(0, mount(NULL, TMP_DIR, NULL, MS_PRIVATE | MS_REC, NULL));
+ clear_cap(_metadata, CAP_SYS_ADMIN);
+}
+
+static void prepare_layout(struct __test_metadata *const _metadata)
+{
+ prepare_layout_opt(_metadata, &mnt_tmp);
+}
+
+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));
+}
+
+/* clang-format off */
+FIXTURE(layout0) {};
+/* clang-format on */
+
+FIXTURE_SETUP(layout0)
+{
+ prepare_layout(_metadata);
+}
+
+FIXTURE_TEARDOWN(layout0)
+{
+ cleanup_layout(_metadata);
+}
+
+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_opt(&mnt_tmp, dir_s3d2));
+ 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(dir_s1d3));
+
+ 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(dir_s2d2));
+
+ 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(layout0, 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(layout0, 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(layout0, unpriv)
+{
+ const struct rule rules[] = {
+ {
+ .path = TMP_DIR,
+ .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(layout0, max_layers)
+{
+ int i, err;
+ const struct rule rules[] = {
+ {
+ .path = TMP_DIR,
+ .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
+ */
+
+FIXTURE(layout2_overlay)
+{
+ bool skip_test;
+};
+
+FIXTURE_SETUP(layout2_overlay)
+{
+ if (!supports_filesystem("overlay")) {
+ self->skip_test = true;
+ SKIP(return, "overlayfs is not supported (setup)");
+ }
+
+ 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_opt(&mnt_tmp, LOWER_BASE));
+ 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_opt(&mnt_tmp, UPPER_BASE));
+ 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 (self->skip_test)
+ SKIP(return, "overlayfs is not supported (teardown)");
+
+ 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 (self->skip_test)
+ SKIP(return, "overlayfs is not supported (test)");
+
+ 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 (self->skip_test)
+ SKIP(return, "overlayfs is not supported (test)");
+
+ /* 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));
+ }
+}
+
+FIXTURE(layout3_fs)
+{
+ bool has_created_dir;
+ bool has_created_file;
+ char *dir_path;
+ bool skip_test;
+};
+
+FIXTURE_VARIANT(layout3_fs)
+{
+ const struct mnt_opt mnt;
+ const char *const file_path;
+ unsigned int cwd_fs_magic;
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(layout3_fs, tmpfs) {
+ /* clang-format on */
+ .mnt = mnt_tmp,
+ .file_path = file1_s1d1,
+};
+
+FIXTURE_VARIANT_ADD(layout3_fs, ramfs) {
+ .mnt = {
+ .type = "ramfs",
+ .data = "mode=700",
+ },
+ .file_path = TMP_DIR "/dir/file",
+};
+
+FIXTURE_VARIANT_ADD(layout3_fs, cgroup2) {
+ .mnt = {
+ .type = "cgroup2",
+ },
+ .file_path = TMP_DIR "/test/cgroup.procs",
+};
+
+FIXTURE_VARIANT_ADD(layout3_fs, proc) {
+ .mnt = {
+ .type = "proc",
+ },
+ .file_path = TMP_DIR "/self/status",
+};
+
+FIXTURE_VARIANT_ADD(layout3_fs, sysfs) {
+ .mnt = {
+ .type = "sysfs",
+ },
+ .file_path = TMP_DIR "/kernel/notes",
+};
+
+FIXTURE_VARIANT_ADD(layout3_fs, hostfs) {
+ .mnt = {
+ .source = TMP_DIR,
+ .flags = MS_BIND,
+ },
+ .file_path = TMP_DIR "/dir/file",
+ .cwd_fs_magic = HOSTFS_SUPER_MAGIC,
+};
+
+FIXTURE_SETUP(layout3_fs)
+{
+ struct stat statbuf;
+ const char *slash;
+ size_t dir_len;
+
+ if (!supports_filesystem(variant->mnt.type) ||
+ !cwd_matches_fs(variant->cwd_fs_magic)) {
+ self->skip_test = true;
+ SKIP(return, "this filesystem is not supported (setup)");
+ }
+
+ slash = strrchr(variant->file_path, '/');
+ ASSERT_NE(slash, NULL);
+ dir_len = (size_t)slash - (size_t)variant->file_path;
+ ASSERT_LT(0, dir_len);
+ self->dir_path = malloc(dir_len + 1);
+ self->dir_path[dir_len] = '\0';
+ strncpy(self->dir_path, variant->file_path, dir_len);
+
+ prepare_layout_opt(_metadata, &variant->mnt);
+
+ /* Creates directory when required. */
+ if (stat(self->dir_path, &statbuf)) {
+ set_cap(_metadata, CAP_DAC_OVERRIDE);
+ EXPECT_EQ(0, mkdir(self->dir_path, 0700))
+ {
+ TH_LOG("Failed to create directory \"%s\": %s",
+ self->dir_path, strerror(errno));
+ free(self->dir_path);
+ self->dir_path = NULL;
+ }
+ self->has_created_dir = true;
+ clear_cap(_metadata, CAP_DAC_OVERRIDE);
+ }
+
+ /* Creates file when required. */
+ if (stat(variant->file_path, &statbuf)) {
+ int fd;
+
+ set_cap(_metadata, CAP_DAC_OVERRIDE);
+ fd = creat(variant->file_path, 0600);
+ EXPECT_LE(0, fd)
+ {
+ TH_LOG("Failed to create file \"%s\": %s",
+ variant->file_path, strerror(errno));
+ }
+ EXPECT_EQ(0, close(fd));
+ self->has_created_file = true;
+ clear_cap(_metadata, CAP_DAC_OVERRIDE);
+ }
+}
+
+FIXTURE_TEARDOWN(layout3_fs)
+{
+ if (self->skip_test)
+ SKIP(return, "this filesystem is not supported (teardown)");
+
+ if (self->has_created_file) {
+ set_cap(_metadata, CAP_DAC_OVERRIDE);
+ /*
+ * Don't check for error because the file might already
+ * have been removed (cf. release_inode test).
+ */
+ unlink(variant->file_path);
+ clear_cap(_metadata, CAP_DAC_OVERRIDE);
+ }
+
+ if (self->has_created_dir) {
+ set_cap(_metadata, CAP_DAC_OVERRIDE);
+ /*
+ * Don't check for error because the directory might already
+ * have been removed (cf. release_inode test).
+ */
+ rmdir(self->dir_path);
+ clear_cap(_metadata, CAP_DAC_OVERRIDE);
+ }
+ free(self->dir_path);
+ self->dir_path = NULL;
+
+ cleanup_layout(_metadata);
+}
+
+static void layer3_fs_tag_inode(struct __test_metadata *const _metadata,
+ FIXTURE_DATA(layout3_fs) * self,
+ const FIXTURE_VARIANT(layout3_fs) * variant,
+ const char *const rule_path)
+{
+ const struct rule layer1_allow_read_file[] = {
+ {
+ .path = rule_path,
+ .access = LANDLOCK_ACCESS_FS_READ_FILE,
+ },
+ {},
+ };
+ const struct landlock_ruleset_attr layer2_deny_everything_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE,
+ };
+ const char *const dev_null_path = "/dev/null";
+ int ruleset_fd;
+
+ if (self->skip_test)
+ SKIP(return, "this filesystem is not supported (test)");
+
+ /* Checks without Landlock. */
+ EXPECT_EQ(0, test_open(dev_null_path, O_RDONLY | O_CLOEXEC));
+ EXPECT_EQ(0, test_open(variant->file_path, O_RDONLY | O_CLOEXEC));
+
+ ruleset_fd = create_ruleset(_metadata, LANDLOCK_ACCESS_FS_READ_FILE,
+ layer1_allow_read_file);
+ EXPECT_LE(0, ruleset_fd);
+ enforce_ruleset(_metadata, ruleset_fd);
+ EXPECT_EQ(0, close(ruleset_fd));
+
+ EXPECT_EQ(EACCES, test_open(dev_null_path, O_RDONLY | O_CLOEXEC));
+ EXPECT_EQ(0, test_open(variant->file_path, O_RDONLY | O_CLOEXEC));
+
+ /* Forbids directory reading. */
+ ruleset_fd =
+ landlock_create_ruleset(&layer2_deny_everything_attr,
+ sizeof(layer2_deny_everything_attr), 0);
+ EXPECT_LE(0, ruleset_fd);
+ enforce_ruleset(_metadata, ruleset_fd);
+ EXPECT_EQ(0, close(ruleset_fd));
+
+ /* Checks with Landlock and forbidden access. */
+ EXPECT_EQ(EACCES, test_open(dev_null_path, O_RDONLY | O_CLOEXEC));
+ EXPECT_EQ(EACCES, test_open(variant->file_path, O_RDONLY | O_CLOEXEC));
+}
+
+/* Matrix of tests to check file hierarchy evaluation. */
+
+TEST_F_FORK(layout3_fs, tag_inode_dir_parent)
+{
+ /* The current directory must not be the root for this test. */
+ layer3_fs_tag_inode(_metadata, self, variant, ".");
+}
+
+TEST_F_FORK(layout3_fs, tag_inode_dir_mnt)
+{
+ layer3_fs_tag_inode(_metadata, self, variant, TMP_DIR);
+}
+
+TEST_F_FORK(layout3_fs, tag_inode_dir_child)
+{
+ layer3_fs_tag_inode(_metadata, self, variant, self->dir_path);
+}
+
+TEST_F_FORK(layout3_fs, tag_inode_file)
+{
+ layer3_fs_tag_inode(_metadata, self, variant, variant->file_path);
+}
+
+/* Light version of layout1.release_inodes */
+TEST_F_FORK(layout3_fs, release_inodes)
+{
+ const struct rule layer1[] = {
+ {
+ .path = TMP_DIR,
+ .access = LANDLOCK_ACCESS_FS_READ_DIR,
+ },
+ {},
+ };
+ int ruleset_fd;
+
+ if (self->skip_test)
+ SKIP(return, "this filesystem is not supported (test)");
+
+ /* Clean up for the teardown to not fail. */
+ if (self->has_created_file)
+ EXPECT_EQ(0, remove_path(variant->file_path));
+
+ if (self->has_created_dir)
+ /* Don't check for error because of cgroup specificities. */
+ remove_path(self->dir_path);
+
+ ruleset_fd =
+ create_ruleset(_metadata, LANDLOCK_ACCESS_FS_READ_DIR, layer1);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Unmount the filesystem while it is being used by a ruleset. */
+ set_cap(_metadata, CAP_SYS_ADMIN);
+ ASSERT_EQ(0, umount(TMP_DIR));
+ clear_cap(_metadata, CAP_SYS_ADMIN);
+
+ /* Replaces with a new mount point to simplify FIXTURE_TEARDOWN. */
+ set_cap(_metadata, CAP_SYS_ADMIN);
+ ASSERT_EQ(0, mount_opt(&mnt_tmp, TMP_DIR));
+ clear_cap(_metadata, CAP_SYS_ADMIN);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /* Checks that access to the new mount point is denied. */
+ ASSERT_EQ(EACCES, test_open(TMP_DIR, O_RDONLY));
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/landlock/ptrace_test.c b/tools/testing/selftests/landlock/ptrace_test.c
new file mode 100644
index 0000000000..55e7871631
--- /dev/null
+++ b/tools/testing/selftests/landlock/ptrace_test.c
@@ -0,0 +1,438 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Landlock tests - Ptrace
+ *
+ * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2019-2020 ANSSI
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/landlock.h>
+#include <signal.h>
+#include <sys/prctl.h>
+#include <sys/ptrace.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "common.h"
+
+/* Copied from security/yama/yama_lsm.c */
+#define YAMA_SCOPE_DISABLED 0
+#define YAMA_SCOPE_RELATIONAL 1
+#define YAMA_SCOPE_CAPABILITY 2
+#define YAMA_SCOPE_NO_ATTACH 3
+
+static void create_domain(struct __test_metadata *const _metadata)
+{
+ int ruleset_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = LANDLOCK_ACCESS_FS_MAKE_BLOCK,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ EXPECT_LE(0, ruleset_fd)
+ {
+ TH_LOG("Failed to create a ruleset: %s", strerror(errno));
+ }
+ EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
+ EXPECT_EQ(0, landlock_restrict_self(ruleset_fd, 0));
+ EXPECT_EQ(0, close(ruleset_fd));
+}
+
+static int test_ptrace_read(const pid_t pid)
+{
+ static const char path_template[] = "/proc/%d/environ";
+ char procenv_path[sizeof(path_template) + 10];
+ int procenv_path_size, fd;
+
+ procenv_path_size = snprintf(procenv_path, sizeof(procenv_path),
+ path_template, pid);
+ if (procenv_path_size >= sizeof(procenv_path))
+ return E2BIG;
+
+ fd = open(procenv_path, O_RDONLY | 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 get_yama_ptrace_scope(void)
+{
+ int ret;
+ char buf[2] = {};
+ const int fd = open("/proc/sys/kernel/yama/ptrace_scope", O_RDONLY);
+
+ if (fd < 0)
+ return 0;
+
+ if (read(fd, buf, 1) < 0) {
+ close(fd);
+ return -1;
+ }
+
+ ret = atoi(buf);
+ close(fd);
+ return ret;
+}
+
+/* clang-format off */
+FIXTURE(hierarchy) {};
+/* clang-format on */
+
+FIXTURE_VARIANT(hierarchy)
+{
+ const bool domain_both;
+ const bool domain_parent;
+ const bool domain_child;
+};
+
+/*
+ * Test multiple tracing combinations between a parent process P1 and a child
+ * process P2.
+ *
+ * Yama's scoped ptrace is presumed disabled. If enabled, this optional
+ * restriction is enforced in addition to any Landlock check, which means that
+ * all P2 requests to trace P1 would be denied.
+ */
+
+/*
+ * No domain
+ *
+ * P1-. P1 -> P2 : allow
+ * \ P2 -> P1 : allow
+ * 'P2
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, allow_without_domain) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = false,
+ .domain_child = false,
+};
+
+/*
+ * Child domain
+ *
+ * P1--. P1 -> P2 : allow
+ * \ P2 -> P1 : deny
+ * .'-----.
+ * | P2 |
+ * '------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, allow_with_one_domain) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = false,
+ .domain_child = true,
+};
+
+/*
+ * Parent domain
+ * .------.
+ * | P1 --. P1 -> P2 : deny
+ * '------' \ P2 -> P1 : allow
+ * '
+ * P2
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, deny_with_parent_domain) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = true,
+ .domain_child = false,
+};
+
+/*
+ * Parent + child domain (siblings)
+ * .------.
+ * | P1 ---. P1 -> P2 : deny
+ * '------' \ P2 -> P1 : deny
+ * .---'--.
+ * | P2 |
+ * '------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, deny_with_sibling_domain) {
+ /* clang-format on */
+ .domain_both = false,
+ .domain_parent = true,
+ .domain_child = true,
+};
+
+/*
+ * Same domain (inherited)
+ * .-------------.
+ * | P1----. | P1 -> P2 : allow
+ * | \ | P2 -> P1 : allow
+ * | ' |
+ * | P2 |
+ * '-------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, allow_sibling_domain) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = false,
+ .domain_child = false,
+};
+
+/*
+ * Inherited + child domain
+ * .-----------------.
+ * | P1----. | P1 -> P2 : allow
+ * | \ | P2 -> P1 : deny
+ * | .-'----. |
+ * | | P2 | |
+ * | '------' |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, allow_with_nested_domain) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = false,
+ .domain_child = true,
+};
+
+/*
+ * Inherited + parent domain
+ * .-----------------.
+ * |.------. | P1 -> P2 : deny
+ * || P1 ----. | P2 -> P1 : allow
+ * |'------' \ |
+ * | ' |
+ * | P2 |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, deny_with_nested_and_parent_domain) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = true,
+ .domain_child = false,
+};
+
+/*
+ * Inherited + parent and child domain (siblings)
+ * .-----------------.
+ * | .------. | P1 -> P2 : deny
+ * | | P1 . | P2 -> P1 : deny
+ * | '------'\ |
+ * | \ |
+ * | .--'---. |
+ * | | P2 | |
+ * | '------' |
+ * '-----------------'
+ */
+/* clang-format off */
+FIXTURE_VARIANT_ADD(hierarchy, deny_with_forked_domain) {
+ /* clang-format on */
+ .domain_both = true,
+ .domain_parent = true,
+ .domain_child = true,
+};
+
+FIXTURE_SETUP(hierarchy)
+{
+}
+
+FIXTURE_TEARDOWN(hierarchy)
+{
+}
+
+/* Test PTRACE_TRACEME and PTRACE_ATTACH for parent and child. */
+TEST_F(hierarchy, trace)
+{
+ pid_t child, parent;
+ int status, err_proc_read;
+ int pipe_child[2], pipe_parent[2];
+ int yama_ptrace_scope;
+ char buf_parent;
+ long ret;
+ bool can_read_child, can_trace_child, can_read_parent, can_trace_parent;
+
+ yama_ptrace_scope = get_yama_ptrace_scope();
+ ASSERT_LE(0, yama_ptrace_scope);
+
+ if (yama_ptrace_scope > YAMA_SCOPE_DISABLED)
+ TH_LOG("Incomplete tests due to Yama restrictions (scope %d)",
+ yama_ptrace_scope);
+
+ /*
+ * can_read_child is true if a parent process can read its child
+ * process, which is only the case when the parent process is not
+ * isolated from the child with a dedicated Landlock domain.
+ */
+ can_read_child = !variant->domain_parent;
+
+ /*
+ * can_trace_child is true if a parent process can trace its child
+ * process. This depends on two conditions:
+ * - The parent process is not isolated from the child with a dedicated
+ * Landlock domain.
+ * - Yama allows tracing children (up to YAMA_SCOPE_RELATIONAL).
+ */
+ can_trace_child = can_read_child &&
+ yama_ptrace_scope <= YAMA_SCOPE_RELATIONAL;
+
+ /*
+ * can_read_parent is true if a child process can read its parent
+ * process, which is only the case when the child process is not
+ * isolated from the parent with a dedicated Landlock domain.
+ */
+ can_read_parent = !variant->domain_child;
+
+ /*
+ * can_trace_parent is true if a child process can trace its parent
+ * process. This depends on two conditions:
+ * - The child process is not isolated from the parent with a dedicated
+ * Landlock domain.
+ * - Yama is disabled (YAMA_SCOPE_DISABLED).
+ */
+ can_trace_parent = can_read_parent &&
+ yama_ptrace_scope <= YAMA_SCOPE_DISABLED;
+
+ /*
+ * Removes all effective and permitted capabilities to not interfere
+ * with cap_ptrace_access_check() in case of PTRACE_MODE_FSCREDS.
+ */
+ drop_caps(_metadata);
+
+ parent = getpid();
+ ASSERT_EQ(0, pipe2(pipe_child, O_CLOEXEC));
+ ASSERT_EQ(0, pipe2(pipe_parent, O_CLOEXEC));
+ if (variant->domain_both) {
+ create_domain(_metadata);
+ if (!_metadata->passed)
+ /* Aborts before forking. */
+ return;
+ }
+
+ child = fork();
+ ASSERT_LE(0, child);
+ if (child == 0) {
+ char buf_child;
+
+ ASSERT_EQ(0, close(pipe_parent[1]));
+ ASSERT_EQ(0, close(pipe_child[0]));
+ if (variant->domain_child)
+ create_domain(_metadata);
+
+ /* Waits for the parent to be in a domain, if any. */
+ ASSERT_EQ(1, read(pipe_parent[0], &buf_child, 1));
+
+ /* Tests PTRACE_MODE_READ on the parent. */
+ err_proc_read = test_ptrace_read(parent);
+ if (can_read_parent) {
+ EXPECT_EQ(0, err_proc_read);
+ } else {
+ EXPECT_EQ(EACCES, err_proc_read);
+ }
+
+ /* Tests PTRACE_ATTACH on the parent. */
+ ret = ptrace(PTRACE_ATTACH, parent, NULL, 0);
+ if (can_trace_parent) {
+ EXPECT_EQ(0, ret);
+ } else {
+ EXPECT_EQ(-1, ret);
+ EXPECT_EQ(EPERM, errno);
+ }
+ if (ret == 0) {
+ ASSERT_EQ(parent, waitpid(parent, &status, 0));
+ ASSERT_EQ(1, WIFSTOPPED(status));
+ ASSERT_EQ(0, ptrace(PTRACE_DETACH, parent, NULL, 0));
+ }
+
+ /* Tests child PTRACE_TRACEME. */
+ ret = ptrace(PTRACE_TRACEME);
+ if (can_trace_child) {
+ EXPECT_EQ(0, ret);
+ } else {
+ EXPECT_EQ(-1, ret);
+ EXPECT_EQ(EPERM, errno);
+ }
+
+ /*
+ * Signals that the PTRACE_ATTACH test is done and the
+ * PTRACE_TRACEME test is ongoing.
+ */
+ ASSERT_EQ(1, write(pipe_child[1], ".", 1));
+
+ if (can_trace_child) {
+ ASSERT_EQ(0, raise(SIGSTOP));
+ }
+
+ /* Waits for the parent PTRACE_ATTACH test. */
+ ASSERT_EQ(1, read(pipe_parent[0], &buf_child, 1));
+ _exit(_metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
+ return;
+ }
+
+ ASSERT_EQ(0, close(pipe_child[1]));
+ ASSERT_EQ(0, close(pipe_parent[0]));
+ if (variant->domain_parent)
+ create_domain(_metadata);
+
+ /* Signals that the parent is in a domain, if any. */
+ ASSERT_EQ(1, write(pipe_parent[1], ".", 1));
+
+ /*
+ * Waits for the child to test PTRACE_ATTACH on the parent and start
+ * testing PTRACE_TRACEME.
+ */
+ ASSERT_EQ(1, read(pipe_child[0], &buf_parent, 1));
+
+ /* Tests child PTRACE_TRACEME. */
+ if (can_trace_child) {
+ ASSERT_EQ(child, waitpid(child, &status, 0));
+ ASSERT_EQ(1, WIFSTOPPED(status));
+ ASSERT_EQ(0, ptrace(PTRACE_DETACH, child, NULL, 0));
+ } else {
+ /* The child should not be traced by the parent. */
+ EXPECT_EQ(-1, ptrace(PTRACE_DETACH, child, NULL, 0));
+ EXPECT_EQ(ESRCH, errno);
+ }
+
+ /* Tests PTRACE_MODE_READ on the child. */
+ err_proc_read = test_ptrace_read(child);
+ if (can_read_child) {
+ EXPECT_EQ(0, err_proc_read);
+ } else {
+ EXPECT_EQ(EACCES, err_proc_read);
+ }
+
+ /* Tests PTRACE_ATTACH on the child. */
+ ret = ptrace(PTRACE_ATTACH, child, NULL, 0);
+ if (can_trace_child) {
+ EXPECT_EQ(0, ret);
+ } else {
+ EXPECT_EQ(-1, ret);
+ EXPECT_EQ(EPERM, errno);
+ }
+
+ if (ret == 0) {
+ ASSERT_EQ(child, waitpid(child, &status, 0));
+ ASSERT_EQ(1, WIFSTOPPED(status));
+ ASSERT_EQ(0, ptrace(PTRACE_DETACH, child, NULL, 0));
+ }
+
+ /* Signals that the parent PTRACE_ATTACH test is done. */
+ ASSERT_EQ(1, write(pipe_parent[1], ".", 1));
+ ASSERT_EQ(child, waitpid(child, &status, 0));
+ if (WIFSIGNALED(status) || !WIFEXITED(status) ||
+ WEXITSTATUS(status) != EXIT_SUCCESS)
+ _metadata->passed = 0;
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/landlock/true.c b/tools/testing/selftests/landlock/true.c
new file mode 100644
index 0000000000..3f9ccbf527
--- /dev/null
+++ b/tools/testing/selftests/landlock/true.c
@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0
+int main(void)
+{
+ return 0;
+}