[PATCH v26 00/12] Landlock LSM

@@ -9827,6 +9827,16 @@ F:	net/core/sock_map.c
 F:	net/ipv4/tcp_bpf.c
 F:	net/ipv4/udp_bpf.c
 
+LANDLOCK SECURITY MODULE
+M:	Mickaël Salaün <mic@digikod.net>
+L:	linux-security-module@vger.kernel.org
+S:	Supported
+W:	https://landlock.io
+T:	git https://github.com/landlock-lsm/linux.git
+F:	security/landlock/
+K:	landlock
+K:	LANDLOCK
+
 LANTIQ / INTEL Ethernet drivers
 M:	Hauke Mehrtens <hauke@hauke-m.de>
 L:	netdev@vger.kernel.org

@@ -238,6 +238,7 @@ source "security/loadpin/Kconfig"
 source "security/yama/Kconfig"
 source "security/safesetid/Kconfig"
 source "security/lockdown/Kconfig"
+source "security/landlock/Kconfig"
 
 source "security/integrity/Kconfig"
 

@@ -13,6 +13,7 @@ subdir-$(CONFIG_SECURITY_LOADPIN)	+= loadpin
 subdir-$(CONFIG_SECURITY_SAFESETID)    += safesetid
 subdir-$(CONFIG_SECURITY_LOCKDOWN_LSM)	+= lockdown
 subdir-$(CONFIG_BPF_LSM)		+= bpf
+subdir-$(CONFIG_SECURITY_LANDLOCK)		+= landlock
 
 # always enable default capabilities
 obj-y					+= commoncap.o

@@ -32,6 +33,7 @@ obj-$(CONFIG_SECURITY_SAFESETID)       += safesetid/
 obj-$(CONFIG_SECURITY_LOCKDOWN_LSM)	+= lockdown/
 obj-$(CONFIG_CGROUPS)			+= device_cgroup.o
 obj-$(CONFIG_BPF_LSM)			+= bpf/
+obj-$(CONFIG_SECURITY_LANDLOCK)	+= landlock/
 
 # Object integrity file lists
 subdir-$(CONFIG_INTEGRITY)		+= integrity

@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config SECURITY_LANDLOCK
+	bool "Landlock support"
+	depends on SECURITY
+	select SECURITY_PATH
+	help
+	  Landlock is a safe sandboxing mechanism which enables processes to
+	  restrict themselves (and their future children) by gradually
+	  enforcing tailored access control policies.  A security policy is a
+	  set of access rights (e.g. open a file in read-only, make a
+	  directory, etc.) tied to a file hierarchy.  Such policy can be configured
+	  and enforced by any processes for themselves thanks to dedicated system
+	  calls: landlock_create_ruleset(), landlock_add_rule(), and
+	  landlock_enforce_ruleset_current().
+
+	  See Documentation/userspace-api/landlock.rst for further information.
+
+	  If you are unsure how to answer this question, answer N.  Otherwise, you
+	  should also prepend "landlock," to the content of CONFIG_LSM to enable
+	  Landlock at boot time.

@@ -0,0 +1,3 @@
+obj-$(CONFIG_SECURITY_LANDLOCK) := landlock.o
+
+landlock-y := object.o

@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Landlock LSM - Object management
+ *
+ * Copyright © 2016-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2018-2020 ANSSI
+ */
+
+#include <linux/bug.h>
+#include <linux/compiler_types.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/rcupdate.h>
+#include <linux/refcount.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "object.h"
+
+struct landlock_object *landlock_create_object(
+		const struct landlock_object_underops *const underops,
+		void *const underobj)
+{
+	struct landlock_object *new_object;
+
+	if (WARN_ON_ONCE(!underops || !underobj))
+		return ERR_PTR(-ENOENT);
+	new_object = kzalloc(sizeof(*new_object), GFP_KERNEL_ACCOUNT);
+	if (!new_object)
+		return ERR_PTR(-ENOMEM);
+	refcount_set(&new_object->usage, 1);
+	spin_lock_init(&new_object->lock);
+	new_object->underops = underops;
+	new_object->underobj = underobj;
+	return new_object;
+}
+
+/*
+ * The caller must own the object (i.e. thanks to object->usage) to safely put
+ * it.
+ */
+void landlock_put_object(struct landlock_object *const object)
+{
+	/*
+	 * The call to @object->underops->release(object) might sleep, e.g.
+	 * because of iput().
+	 */
+	might_sleep();
+	if (!object)
+		return;
+
+	/*
+	 * If the @object's refcount cannot drop to zero, we can just decrement
+	 * the refcount without holding a lock. Otherwise, the decrement must
+	 * happen under @object->lock for synchronization with things like
+	 * get_inode_object().
+	 */
+	if (refcount_dec_and_lock(&object->usage, &object->lock)) {
+		__acquire(&object->lock);
+		/*
+		 * With @object->lock initially held, remove the reference from
+		 * @object->underobj to @object (if it still exists).
+		 */
+		object->underops->release(object);
+		kfree_rcu(object, rcu_free);
+	}
+}

@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Landlock LSM - Object management
+ *
+ * Copyright © 2016-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2018-2020 ANSSI
+ */
+
+#ifndef _SECURITY_LANDLOCK_OBJECT_H
+#define _SECURITY_LANDLOCK_OBJECT_H
+
+#include <linux/compiler_types.h>
+#include <linux/refcount.h>
+#include <linux/spinlock.h>
+
+struct landlock_object;
+
+/**
+ * struct landlock_object_underops - Operations on an underlying object
+ */
+struct landlock_object_underops {
+	/**
+	 * @release: Releases the underlying object (e.g. iput() for an inode).
+	 */
+	void (*release)(struct landlock_object *const object)
+		__releases(object->lock);
+};
+
+/**
+ * struct landlock_object - Security blob tied to a kernel object
+ *
+ * The goal of this structure is to enable to tie a set of ephemeral access
+ * rights (pertaining to different domains) to a kernel object (e.g an inode)
+ * in a safe way.  This imply to handle concurrent use and modification.
+ *
+ * The lifetime of a &struct landlock_object depends of the rules referring to
+ * it.
+ */
+struct landlock_object {
+	/**
+	 * @usage: This counter is used to tie an object to the rules matching
+	 * it or to keep it alive while adding a new rule.  If this counter
+	 * reaches zero, this struct must not be modified, but this counter can
+	 * still be read from within an RCU read-side critical section.  When
+	 * adding a new rule to an object with a usage counter of zero, we must
+	 * wait until the pointer to this object is set to NULL (or recycled).
+	 */
+	refcount_t usage;
+	/**
+	 * @lock: Guards against concurrent modifications.  This lock must be
+	 * held from the time @usage drops to zero until any weak references
+	 * from @underobj to this object have been cleaned up.
+	 *
+	 * Lock ordering: inode->i_lock nests inside this.
+	 */
+	spinlock_t lock;
+	/**
+	 * @underobj: Used when cleaning up an object and to mark an object as
+	 * tied to its underlying kernel structure.  This pointer is protected
+	 * by @lock.  Cf. landlock_release_inodes() and release_inode().
+	 */
+	void *underobj;
+	union {
+		/**
+		 * @rcu_free: Enables lockless use of @usage, @lock and
+		 * @underobj from within an RCU read-side critical section.
+		 * @rcu_free and @underops are only used by
+		 * landlock_put_object().
+		 */
+		struct rcu_head rcu_free;
+		/**
+		 * @underops: Enables landlock_put_object() to release the
+		 * underlying object (e.g. inode).
+		 */
+		const struct landlock_object_underops *underops;
+	};
+};
+
+struct landlock_object *landlock_create_object(
+		const struct landlock_object_underops *const underops,
+		void *const underobj);
+
+void landlock_put_object(struct landlock_object *const object);
+
+static inline void landlock_get_object(struct landlock_object *const object)
+{
+	if (object)
+		refcount_inc(&object->usage);
+}
+
+#endif /* _SECURITY_LANDLOCK_OBJECT_H */

@@ -1,4 +1,4 @@
 obj-$(CONFIG_SECURITY_LANDLOCK) := landlock.o
 
 landlock-y := setup.o object.o ruleset.o \
-	cred.o
+	cred.o ptrace.o

@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Landlock LSM - Ptrace hooks
+ *
+ * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2019-2020 ANSSI
+ */
+
+#include <asm/current.h>
+#include <linux/cred.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/lsm_hooks.h>
+#include <linux/rcupdate.h>
+#include <linux/sched.h>
+
+#include "common.h"
+#include "cred.h"
+#include "ptrace.h"
+#include "ruleset.h"
+#include "setup.h"
+
+/**
+ * domain_scope_le - Checks domain ordering for scoped ptrace
+ *
+ * @parent: Parent domain.
+ * @child: Potential child of @parent.
+ *
+ * Checks if the @parent domain is less or equal to (i.e. an ancestor, which
+ * means a subset of) the @child domain.
+ */
+static bool domain_scope_le(const struct landlock_ruleset *const parent,
+		const struct landlock_ruleset *const child)
+{
+	const struct landlock_hierarchy *walker;
+
+	if (!parent)
+		return true;
+	if (!child)
+		return false;
+	for (walker = child->hierarchy; walker; walker = walker->parent) {
+		if (walker == parent->hierarchy)
+			/* @parent is in the scoped hierarchy of @child. */
+			return true;
+	}
+	/* There is no relationship between @parent and @child. */
+	return false;
+}
+
+static bool task_is_scoped(const struct task_struct *const parent,
+		const struct task_struct *const child)
+{
+	bool is_scoped;
+	const struct landlock_ruleset *dom_parent, *dom_child;
+
+	rcu_read_lock();
+	dom_parent = landlock_get_task_domain(parent);
+	dom_child = landlock_get_task_domain(child);
+	is_scoped = domain_scope_le(dom_parent, dom_child);
+	rcu_read_unlock();
+	return is_scoped;
+}
+
+static int task_ptrace(const struct task_struct *const parent,
+		const struct task_struct *const child)
+{
+	/* Quick return for non-landlocked tasks. */
+	if (!landlocked(parent))
+		return 0;
+	if (task_is_scoped(parent, child))
+		return 0;
+	return -EPERM;
+}
+
+/**
+ * hook_ptrace_access_check - Determines whether the current process may access
+ *			      another
+ *
+ * @child: Process to be accessed.
+ * @mode: Mode of attachment.
+ *
+ * If the current task has Landlock rules, then the child must have at least
+ * the same rules.  Else denied.
+ *
+ * Determines whether a process may access another, returning 0 if permission
+ * granted, -errno if denied.
+ */
+static int hook_ptrace_access_check(struct task_struct *const child,
+		const unsigned int mode)
+{
+	return task_ptrace(current, child);
+}
+
+/**
+ * hook_ptrace_traceme - Determines whether another process may trace the
+ *			 current one
+ *
+ * @parent: Task proposed to be the tracer.
+ *
+ * If the parent has Landlock rules, then the current task must have the same
+ * or more rules.  Else denied.
+ *
+ * Determines whether the nominated task is permitted to trace the current
+ * process, returning 0 if permission is granted, -errno if denied.
+ */
+static int hook_ptrace_traceme(struct task_struct *const parent)
+{
+	return task_ptrace(parent, current);
+}
+
+static struct security_hook_list landlock_hooks[] __lsm_ro_after_init = {
+	LSM_HOOK_INIT(ptrace_access_check, hook_ptrace_access_check),
+	LSM_HOOK_INIT(ptrace_traceme, hook_ptrace_traceme),
+};
+
+__init void landlock_add_ptrace_hooks(void)
+{
+	security_add_hooks(landlock_hooks, ARRAY_SIZE(landlock_hooks),
+			LANDLOCK_NAME);
+}

@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Landlock LSM - Ptrace hooks
+ *
+ * Copyright © 2017-2019 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2019 ANSSI
+ */
+
+#ifndef _SECURITY_LANDLOCK_PTRACE_H
+#define _SECURITY_LANDLOCK_PTRACE_H
+
+__init void landlock_add_ptrace_hooks(void);
+
+#endif /* _SECURITY_LANDLOCK_PTRACE_H */

@@ -11,6 +11,7 @@
 
 #include "common.h"
 #include "cred.h"
+#include "ptrace.h"
 #include "setup.h"
 
 struct lsm_blob_sizes landlock_blob_sizes __lsm_ro_after_init = {

@@ -20,6 +21,7 @@ struct lsm_blob_sizes landlock_blob_sizes __lsm_ro_after_init = {
 static int __init landlock_init(void)
 {
 	landlock_add_cred_hooks();
+	landlock_add_ptrace_hooks();
 	pr_info("Up and running.\n");
 	return 0;
 }

@@ -454,6 +454,7 @@ void generic_shutdown_super(struct super_block *sb)
 		evict_inodes(sb);
 		/* only nonzero refcount inodes can have marks */
 		fsnotify_sb_delete(sb);
+		security_sb_delete(sb);
 
 		if (sb->s_dio_done_wq) {
 			destroy_workqueue(sb->s_dio_done_wq);

@@ -59,6 +59,7 @@ LSM_HOOK(int, 0, fs_context_dup, struct fs_context *fc,
 LSM_HOOK(int, -ENOPARAM, fs_context_parse_param, struct fs_context *fc,
 	 struct fs_parameter *param)
 LSM_HOOK(int, 0, sb_alloc_security, struct super_block *sb)
+LSM_HOOK(void, LSM_RET_VOID, sb_delete, struct super_block *sb)
 LSM_HOOK(void, LSM_RET_VOID, sb_free_security, struct super_block *sb)
 LSM_HOOK(void, LSM_RET_VOID, sb_free_mnt_opts, void *mnt_opts)
 LSM_HOOK(int, 0, sb_eat_lsm_opts, char *orig, void **mnt_opts)

@@ -108,6 +108,8 @@
  *	allocated.
  *	@sb contains the super_block structure to be modified.
  *	Return 0 if operation was successful.
+ * @sb_delete:
+ *	Release objects tied to a superblock (e.g. inodes).
  * @sb_free_security:
  *	Deallocate and clear the sb->s_security field.
  *	@sb contains the super_block structure to be modified.

@@ -287,6 +287,7 @@ void security_bprm_committed_creds(struct linux_binprm *bprm);
 int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc);
 int security_fs_context_parse_param(struct fs_context *fc, struct fs_parameter *param);
 int security_sb_alloc(struct super_block *sb);
+void security_sb_delete(struct super_block *sb);
 void security_sb_free(struct super_block *sb);
 void security_free_mnt_opts(void **mnt_opts);
 int security_sb_eat_lsm_opts(char *options, void **mnt_opts);

@@ -619,6 +620,9 @@ static inline int security_sb_alloc(struct super_block *sb)
 	return 0;
 }
 
+static inline void security_sb_delete(struct super_block *sb)
+{ }
+
 static inline void security_sb_free(struct super_block *sb)
 { }
 

@@ -899,6 +899,11 @@ int security_sb_alloc(struct super_block *sb)
 	return rc;
 }
 
+void security_sb_delete(struct super_block *sb)
+{
+	call_void_hook(sb_delete, sb);
+}
+
 void security_sb_free(struct super_block *sb)
 {
 	call_void_hook(sb_free_security, sb);

@@ -26,6 +26,7 @@ TARGETS += ir
 TARGETS += kcmp
 TARGETS += kexec
 TARGETS += kvm
+TARGETS += landlock
 TARGETS += lib
 TARGETS += livepatch
 TARGETS += lkdtm

@@ -0,0 +1,2 @@
+/*_test
+/true

@@ -0,0 +1,24 @@
+# SPDX-License-Identifier: GPL-2.0
+
+CFLAGS += -Wall -O2
+
+src_test := $(wildcard *_test.c)
+
+TEST_GEN_PROGS := $(src_test:.c=)
+
+TEST_GEN_PROGS_EXTENDED := true
+
+KSFT_KHDR_INSTALL := 1
+OVERRIDE_TARGETS := 1
+include ../lib.mk
+
+khdr_dir = $(top_srcdir)/usr/include
+
+$(khdr_dir)/linux/landlock.h: khdr
+	@:
+
+$(OUTPUT)/true: true.c
+	$(LINK.c) $< $(LDLIBS) -o $@ -static
+
+$(OUTPUT)/%_test: %_test.c $(khdr_dir)/linux/landlock.h ../kselftest_harness.h common.h
+	$(LINK.c) $< $(LDLIBS) -o $@ -lcap -I$(khdr_dir)

@@ -0,0 +1,219 @@
+// 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(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);
+
+	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(empty_path_beneath_attr) {
+	const struct landlock_ruleset_attr ruleset_attr = {
+		.handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE,
+	};
+	const int ruleset_fd = landlock_create_ruleset(&ruleset_attr,
+			sizeof(ruleset_attr), 0);
+
+	ASSERT_LE(0, ruleset_fd);
+
+	/* Similar to struct landlock_path_beneath_attr.parent_fd = 0 */
+	ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+				NULL, 0));
+	ASSERT_EQ(EFAULT, errno);
+	ASSERT_EQ(0, close(ruleset_fd));
+}
+
+TEST(inval_fd_enforce) {
+	ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
+
+	ASSERT_EQ(-1, landlock_enforce_ruleset_current(-1, 0));
+	ASSERT_EQ(EBADF, errno);
+}
+
+TEST(unpriv_enforce_without_no_new_privs) {
+	int err;
+
+	disable_caps(_metadata);
+	err = landlock_enforce_ruleset_current(-1, 0);
+	ASSERT_EQ(EPERM, errno);
+	ASSERT_EQ(err, -1);
+}
+
+TEST(ruleset_fd_io)
+{
+	struct landlock_ruleset_attr ruleset_attr = {
+		.handled_access_fs = LANDLOCK_ACCESS_FS_READ_FILE,
+	};
+	int ruleset_fd;
+	char buf;
+
+	disable_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 transfered 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;
+	union {
+		/* Aligned ancillary data buffer. */
+		char buf[CMSG_SPACE(sizeof(ruleset_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;
+	int socket_fds[2];
+	pid_t child;
+	int status;
+
+	disable_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));
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	ASSERT_NE(NULL, cmsg);
+	cmsg->cmsg_len = CMSG_LEN(sizeof(ruleset_fd_tx));
+	cmsg->cmsg_level = SOL_SOCKET;
+	cmsg->cmsg_type = SCM_RIGHTS;
+	memcpy(CMSG_DATA(cmsg), &ruleset_fd_tx, sizeof(ruleset_fd_tx));
+
+	/* 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(sizeof(data_tx), sendmsg(socket_fds[0], &msg, 0));
+	ASSERT_EQ(0, close(socket_fds[0]));
+	ASSERT_EQ(0, close(ruleset_fd_tx));
+
+	child = fork();
+	ASSERT_LE(0, child);
+	if (child == 0) {
+		int ruleset_fd_rx;
+
+		*(char *)msg.msg_iov->iov_base = '\0';
+		ASSERT_EQ(sizeof(data_tx), recvmsg(socket_fds[1], &msg, MSG_CMSG_CLOEXEC));
+		ASSERT_EQ('.', *(char *)msg.msg_iov->iov_base);
+		ASSERT_EQ(0, close(socket_fds[1]));
+		cmsg = CMSG_FIRSTHDR(&msg);
+		ASSERT_EQ(cmsg->cmsg_len, CMSG_LEN(sizeof(ruleset_fd_tx)));
+		memcpy(&ruleset_fd_rx, CMSG_DATA(cmsg), sizeof(ruleset_fd_tx));
+
+		/* Enforces the received ruleset on the child. */
+		ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
+		ASSERT_EQ(0, landlock_enforce_ruleset_current(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

@@ -0,0 +1,110 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Landlock test helpers
+ *
+ * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2019-2020 ANSSI
+ */
+
+#include <errno.h>
+#include <linux/landlock.h>
+#include <sys/capability.h>
+#include <sys/syscall.h>
+
+#include "../kselftest_harness.h"
+
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#endif
+
+#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_enforce_ruleset_current
+static inline int landlock_enforce_ruleset_current(const int ruleset_fd,
+		const __u32 flags)
+{
+	return syscall(__NR_landlock_enforce_ruleset_current, ruleset_fd,
+			flags);
+}
+#endif
+
+static void disable_caps(struct __test_metadata *const _metadata)
+{
+	cap_t cap_p;
+	/* Only these three capabilities are useful for the tests. */
+	const cap_value_t caps[] = {
+		CAP_MKNOD,
+		CAP_SYS_ADMIN,
+		CAP_SYS_CHROOT,
+	};
+
+	cap_p = cap_get_proc();
+	ASSERT_NE(NULL, cap_p) {
+		TH_LOG("Failed to cap_get_proc: %s", strerror(errno));
+	}
+	ASSERT_NE(-1, cap_clear(cap_p)) {
+		TH_LOG("Failed to cap_clear: %s", strerror(errno));
+	}
+	ASSERT_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));
+	}
+	ASSERT_NE(-1, cap_set_proc(cap_p)) {
+		TH_LOG("Failed to cap_set_proc: %s", strerror(errno));
+	}
+	ASSERT_NE(-1, cap_free(cap_p)) {
+		TH_LOG("Failed to cap_free: %s", strerror(errno));
+	}
+}
+
+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();
+	ASSERT_NE(NULL, cap_p) {
+		TH_LOG("Failed to cap_get_proc: %s", strerror(errno));
+	}
+	ASSERT_NE(-1, cap_set_flag(cap_p, CAP_EFFECTIVE, 1, &caps, value)) {
+		TH_LOG("Failed to cap_set_flag: %s", strerror(errno));
+	}
+	ASSERT_NE(-1, cap_set_proc(cap_p)) {
+		TH_LOG("Failed to cap_set_proc: %s", strerror(errno));
+	}
+	ASSERT_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 . */
+__attribute__((__unused__))
+static void set_cap(struct __test_metadata *const _metadata,
+		const cap_value_t caps)
+{
+	effective_cap(_metadata, caps, CAP_SET);
+}
+
+__attribute__((__unused__))
+static void clear_cap(struct __test_metadata *const _metadata,
+		const cap_value_t caps)
+{
+	effective_cap(_metadata, caps, CAP_CLEAR);
+}

@@ -0,0 +1,5 @@
+CONFIG_SECURITY_LANDLOCK=y
+CONFIG_SECURITY_PATH=y
+CONFIG_SECURITY=y
+CONFIG_SHMEM=y
+CONFIG_TMPFS=y

@@ -0,0 +1,1799 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Landlock tests - Filesystem
+ *
+ * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
+ * Copyright © 2020 ANSSI
+ * Copyright © 2020 Microsoft Corporation
+ */
+
+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <linux/landlock.h>
+#include <sched.h>
+#include <string.h>
+#include <sys/capability.h>
+#include <sys/mount.h>
+#include <sys/prctl.h>
+#include <sys/sendfile.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <unistd.h>
+
+#include "common.h"
+
+#define TMP_DIR "tmp/"
+#define FILE_1 "file1"
+#define FILE_2 "file2"
+#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/" FILE_1;
+static const char file2_s1d1[] = TMP_DIR "s1d1/" FILE_2;
+static const char dir_s1d2[] = TMP_DIR "s1d1/s1d2";
+static const char file1_s1d2[] = TMP_DIR "s1d1/s1d2/" FILE_1;
+static const char file2_s1d2[] = TMP_DIR "s1d1/s1d2/" FILE_2;
+static const char dir_s1d3[] = TMP_DIR "s1d1/s1d2/s1d3";
+static const char file1_s1d3[] = TMP_DIR "s1d1/s1d2/s1d3/" FILE_1;
+static const char file2_s1d3[] = TMP_DIR "s1d1/s1d2/s1d3/" FILE_2;
+
+static const char dir_s2d1[] = TMP_DIR "s2d1";
+static const char file1_s2d1[] = TMP_DIR "s2d1/" FILE_1;
+static const char dir_s2d2[] = TMP_DIR "s2d1/s2d2";
+static const char file1_s2d2[] = TMP_DIR "s2d1/s2d2/" FILE_1;
+static const char dir_s2d3[] = TMP_DIR "s2d1/s2d2/s2d3";
+static const char file1_s2d3[] = TMP_DIR "s2d1/s2d2/s2d3/" FILE_1;
+static const char file2_s2d3[] = TMP_DIR "s2d1/s2d2/s2d3/" FILE_2;
+
+static const char dir_s3d1[] = TMP_DIR "s3d1";
+/* 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";
+
+static void create_dir_and_file(struct __test_metadata *const _metadata,
+		const char *const dir_path)
+{
+	int file_fd;
+	char *const file1_path = alloca(strlen(dir_path) + sizeof(FILE_1) + 2);
+	char *const file2_path = alloca(strlen(dir_path) + sizeof(FILE_2) + 2);
+
+	strcpy(file1_path, dir_path);
+	strcat(file1_path, "/");
+	strcat(file1_path, FILE_1);
+
+	strcpy(file2_path, dir_path);
+	strcat(file2_path, "/");
+	strcat(file2_path, FILE_2);
+
+	ASSERT_EQ(0, mkdir(dir_path, 0700)) {
+		TH_LOG("Failed to create directory \"%s\": %s", dir_path,
+				strerror(errno));
+	}
+	file_fd = open(file1_path, O_CREAT | O_EXCL | O_WRONLY | O_CLOEXEC,
+			0700);
+	ASSERT_LE(0, file_fd);
+	ASSERT_EQ(0, close(file_fd));
+
+	file_fd = open(file2_path, O_CREAT | O_EXCL | O_WRONLY | O_CLOEXEC,
+			0700);
+	ASSERT_LE(0, file_fd);
+	ASSERT_EQ(0, close(file_fd));
+}
+
+static void delete_dir_and_file(const char *const dir_path)
+{
+	char *const file1_path = alloca(strlen(dir_path) +
+			sizeof(FILE_1) + 2);
+	char *const file2_path = alloca(strlen(dir_path) +
+			sizeof(FILE_2) + 2);
+
+	strcpy(file1_path, dir_path);
+	strcat(file1_path, "/");
+	strcat(file1_path, FILE_1);
+
+	strcpy(file2_path, dir_path);
+	strcat(file2_path, "/");
+	strcat(file2_path, FILE_2);
+
+	unlink(file1_path);
+	unlink(file2_path);
+	/* file1_path may be a directory, cf. layout1/make_directory. */
+	rmdir(file1_path);
+	rmdir(dir_path);
+}
+
+static void cleanup_layout1(struct __test_metadata *const _metadata)
+{
+	delete_dir_and_file(dir_s1d3);
+	delete_dir_and_file(dir_s1d2);
+	delete_dir_and_file(dir_s1d1);
+
+	delete_dir_and_file(dir_s2d3);
+	delete_dir_and_file(dir_s2d2);
+	delete_dir_and_file(dir_s2d1);
+
+	delete_dir_and_file(dir_s3d3);
+	set_cap(_metadata, CAP_SYS_ADMIN);
+	umount(dir_s3d2);
+	clear_cap(_metadata, CAP_SYS_ADMIN);
+	delete_dir_and_file(dir_s3d2);
+	delete_dir_and_file(dir_s3d1);
+
+	delete_dir_and_file(TMP_DIR);
+}
+
+FIXTURE(layout1) {
+};
+
+FIXTURE_SETUP(layout1)
+{
+	disable_caps(_metadata);
+	cleanup_layout1(_metadata);
+
+	/* Do not pollute the rest of the system. */
+	set_cap(_metadata, CAP_SYS_ADMIN);
+	ASSERT_EQ(0, unshare(CLONE_NEWNS));
+	clear_cap(_metadata, CAP_SYS_ADMIN);
+	umask(0077);
+	create_dir_and_file(_metadata, TMP_DIR);
+
+	create_dir_and_file(_metadata, dir_s1d1);
+	create_dir_and_file(_metadata, dir_s1d2);
+	create_dir_and_file(_metadata, dir_s1d3);
+
+	create_dir_and_file(_metadata, dir_s2d1);
+	create_dir_and_file(_metadata, dir_s2d2);
+	create_dir_and_file(_metadata, dir_s2d3);
+
+	create_dir_and_file(_metadata, dir_s3d1);
+	create_dir_and_file(_metadata, dir_s3d2);
+	set_cap(_metadata, CAP_SYS_ADMIN);
+	ASSERT_EQ(0, mount("tmp", dir_s3d2, "tmpfs", 0, "size=4m,mode=700"));
+	clear_cap(_metadata, CAP_SYS_ADMIN);
+	create_dir_and_file(_metadata, dir_s3d3);
+}
+
+FIXTURE_TEARDOWN(layout1)
+{
+	/*
+	 * cleanup_layout1() would be denied here, use TEST(cleanup) instead.
+	 */
+}
+
+/*
+ * 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;
+	if (close(fd) == 0)
+		return 0;
+	/*
+	 * Mixing error codes from close(2) and open(2) should not lead to any
+	 * (access type) confusion for this test.
+	 */
+	return errno;
+}
+
+static int test_open(const char *const path, const int flags)
+{
+	return test_open_rel(AT_FDCWD, path, flags);
+}
+
+TEST_F(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(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 contains O_PATH. */
+	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(-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));
+
+	/* 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;
+
+	/* 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(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+				&path_beneath, 0));
+	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_enforce_ruleset_current(ruleset_fd, 0));
+
+	ASSERT_EQ(0, close(ruleset_fd));
+}
+
+#define ACCESS_FILE ( \
+	LANDLOCK_ACCESS_FS_EXECUTE | \
+	LANDLOCK_ACCESS_FS_WRITE_FILE | \
+	LANDLOCK_ACCESS_FS_READ_FILE)
+
+#define ACCESS_LAST LANDLOCK_ACCESS_FS_MAKE_SYM
+
+#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 | \
+	ACCESS_LAST)
+
+TEST_F(layout1, file_access_rights)
+{
+	__u64 access;
+	int err;
+	struct landlock_path_beneath_attr path_beneath = {};
+	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.parent_fd = open(file1_s1d2, O_PATH | O_CLOEXEC);
+	ASSERT_LE(0, path_beneath.parent_fd);
+	for (access = 1; access <= ACCESS_LAST; access <<= 1) {
+		path_beneath.allowed_access = access;
+		err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+				&path_beneath, 0);
+		if ((access | ACCESS_FILE) == ACCESS_FILE) {
+			ASSERT_EQ(0, err);
+		} else {
+			ASSERT_EQ(-1, err);
+			ASSERT_EQ(EINVAL, errno);
+		}
+	}
+	ASSERT_EQ(0, close(path_beneath.parent_fd));
+}
+
+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;
+};
+
+#define ACCESS_RO ( \
+	LANDLOCK_ACCESS_FS_READ_FILE | \
+	LANDLOCK_ACCESS_FS_READ_DIR)
+
+#define ACCESS_RW ( \
+	ACCESS_RO | \
+	LANDLOCK_ACCESS_FS_WRITE_FILE)
+
+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_enforce_ruleset_current(ruleset_fd, 0)) {
+		TH_LOG("Failed to enforce ruleset: %s", strerror(errno));
+	}
+}
+
+TEST_F(layout1, proc_nsfs)
+{
+	const struct rule rules[] = {
+		{
+			.path = "/dev/null",
+			.access = LANDLOCK_ACCESS_FS_READ_FILE |
+				LANDLOCK_ACCESS_FS_WRITE_FILE,
+		},
+		{}
+	};
+	struct landlock_path_beneath_attr path_beneath;
+	const int ruleset_fd = create_ruleset(_metadata, rules[0].access |
+			LANDLOCK_ACCESS_FS_READ_DIR, rules);
+
+	ASSERT_LE(0, ruleset_fd);
+	ASSERT_EQ(0, test_open("/proc/self/ns/mnt", O_RDONLY));
+
+	enforce_ruleset(_metadata, ruleset_fd);
+
+	ASSERT_EQ(EACCES, test_open("/", O_RDONLY));
+	ASSERT_EQ(EACCES, test_open("/dev", O_RDONLY));
+	ASSERT_EQ(0, test_open("/dev/null", O_RDONLY));
+	ASSERT_EQ(EACCES, test_open("/dev/full", O_RDONLY));
+
+	ASSERT_EQ(EACCES, test_open("/proc", O_RDONLY));
+	ASSERT_EQ(EACCES, test_open("/proc/self", O_RDONLY));
+	ASSERT_EQ(EACCES, test_open("/proc/self/ns", O_RDONLY));
+	/*
+	 * Because nsfs is an internal filesystem, /proc/self/ns/mnt is a
+	 * disconnected path.  Such path cannot be identified and must then be
+	 * allowed.
+	 */
+	ASSERT_EQ(0, test_open("/proc/self/ns/mnt", O_RDONLY));
+
+	/*
+	 * Checks that it is not possible to add nsfs-like filesystem
+	 * references to a ruleset.
+	 */
+	path_beneath.allowed_access = LANDLOCK_ACCESS_FS_READ_FILE |
+		LANDLOCK_ACCESS_FS_WRITE_FILE,
+	path_beneath.parent_fd = open("/proc/self/ns/mnt", O_PATH | O_CLOEXEC);
+	ASSERT_LE(0, path_beneath.parent_fd);
+	ASSERT_EQ(-1, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+				&path_beneath, 0));
+	ASSERT_EQ(EBADFD, errno);
+	ASSERT_EQ(0, close(path_beneath.parent_fd));
+}
+
+static void drop_privileges(struct __test_metadata *const _metadata)
+{
+	cap_t caps;
+	const cap_value_t cap_val = CAP_SYS_ADMIN;
+
+	caps = cap_get_proc();
+	ASSERT_NE(NULL, caps);
+	ASSERT_EQ(0, cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_val,
+				CAP_CLEAR));
+	ASSERT_EQ(0, cap_set_proc(caps));
+	ASSERT_EQ(0, cap_free(caps));
+}
+
+TEST_F(layout1, unpriv) {
+	const struct rule rules[] = {
+		{
+			.path = dir_s1d2,
+			.access = ACCESS_RO,
+		},
+		{}
+	};
+	int ruleset_fd;
+
+	drop_privileges(_metadata);
+	ruleset_fd = create_ruleset(_metadata, ACCESS_RO, rules);
+	ASSERT_LE(0, ruleset_fd);
+	ASSERT_EQ(-1, landlock_enforce_ruleset_current(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(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. */
+	ASSERT_EQ(EACCES, test_open("/", O_RDONLY));
+	ASSERT_EQ(EACCES, test_open(dir_s1d1, O_RDONLY));
+	ASSERT_EQ(EACCES, 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));
+
+	/* Tests on a file. */
+	ASSERT_EQ(EACCES, test_open(dir_s2d2, O_RDONLY));
+	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(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(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(layout1, interleaved_masked_accesses)
+{
+	/*
+	 * Checks overly restrictive rules:
+	 * layer 1: allows R  s1d1/s1d2/s1d3/file1
+	 * layer 2: allows R  s1d1/s1d2/s1d3
+	 *          denies R  s1d1/s1d2
+	 * layer 3: allows R  s1d1
+	 * layer 4: denies  W s1d1/s1d2
+	 * layer 5: allows R  s1d1/s1d2
+	 * layer 6: denies R  s1d1/s1d2
+	 */
+	const struct rule layer1_read[] = {
+		/* Allows access to file1_s1d3 with the first layer. */
+		{
+			.path = file1_s1d3,
+			.access = LANDLOCK_ACCESS_FS_READ_FILE,
+		},
+		{}
+	};
+	const struct rule layer2_read[] = {
+		/* Start by granting access via its parent directory... */
+		{
+			.path = dir_s1d3,
+			.access = LANDLOCK_ACCESS_FS_READ_FILE,
+		},
+		/* ...but also denies access via its grandparent directory. */
+		{
+			.path = dir_s1d2,
+			.access = 0,
+		},
+		{}
+	};
+	const struct rule layer3_read[] = {
+		/* Allows access via its great-grandparent directory. */
+		{
+			.path = dir_s1d1,
+			.access = LANDLOCK_ACCESS_FS_READ_FILE,
+		},
+		{}
+	};
+	const struct rule layer4_write[] = {
+		/*
+		 * Try to confuse the deny access by denying write (but not
+		 * read) access via its grandparent directory.
+		 */
+		{
+			.path = dir_s1d2,
+			.access = 0,
+		},
+		{}
+	};
+	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_read[] = {
+		/*
+		 * Finally, denies read access to file1_s1d3 via its
+		 * grandparent.
+		 */
+		{
+			.path = dir_s1d2,
+			.access = 0,
+		},
+		{}
+	};
+	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 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,
+			layer2_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 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, creates a write-only rule. */
+	ruleset_fd = create_ruleset(_metadata, LANDLOCK_ACCESS_FS_WRITE_FILE,
+			layer4_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_READ_FILE,
+			layer6_read);
+	ASSERT_LE(0, ruleset_fd);
+	enforce_ruleset(_metadata, ruleset_fd);
+	ASSERT_EQ(0, close(ruleset_fd));
+
+	/* Checks read access is now denied with layer 6. */
+	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(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 now forbidden too. */
+	ASSERT_EQ(EACCES, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
+}
+
+TEST_F(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(layout1, max_layers)
+{
+	int i, err;
+	const struct rule rules[] = {
+		{
+			.path = dir_s1d2,
+			.access = ACCESS_RO,
+		},
+		{}
+	};
+	const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
+
+	ASSERT_LE(0, ruleset_fd);
+	for (i = 0; i < 64; i++)
+		enforce_ruleset(_metadata, ruleset_fd);
+
+	for (i = 0; i < 2; i++) {
+		err = landlock_enforce_ruleset_current(ruleset_fd, 0);
+		ASSERT_EQ(-1, err);
+		ASSERT_EQ(E2BIG, errno);
+	}
+	ASSERT_EQ(0, close(ruleset_fd));
+}
+
+TEST_F(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(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(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(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(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(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, mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL));
+	ASSERT_EQ(0, syscall(SYS_pivot_root, dir_s3d2, dir_s3d3)) {
+		TH_LOG("Failed to pivot_root into \"%s\": %s", dir_s3d2,
+				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(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);
+	set_cap(_metadata, CAP_SYS_ADMIN);
+	ASSERT_EQ(0, mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL));
+
+	enforce_ruleset(_metadata, ruleset_fd);
+	ASSERT_EQ(0, close(ruleset_fd));
+
+	ASSERT_EQ(-1, mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL));
+	ASSERT_EQ(EPERM, errno);
+	ASSERT_EQ(-1, syscall(SYS_pivot_root, dir_s3d2, dir_s3d3));
+	ASSERT_EQ(EPERM, errno);
+}
+
+TEST_F(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, mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL));
+	ASSERT_EQ(0, syscall(SYS_move_mount, AT_FDCWD, dir_s3d2, AT_FDCWD,
+				dir_s1d2, 0)) {
+		TH_LOG("Failed to move_mount: %s", strerror(errno));
+	}
+	ASSERT_EQ(0, syscall(SYS_move_mount, AT_FDCWD, dir_s1d2, AT_FDCWD,
+				dir_s3d2, 0));
+
+	enforce_ruleset(_metadata, ruleset_fd);
+	ASSERT_EQ(0, close(ruleset_fd));
+
+	ASSERT_EQ(-1, syscall(SYS_move_mount, AT_FDCWD, dir_s3d2, AT_FDCWD,
+				dir_s1d2, 0));
+	ASSERT_EQ(EPERM, errno);
+}
+
+TEST_F(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)
+{
+	const struct rule rules[] = {
+		{
+			.path = dir_s1d2,
+			.access = ACCESS_RO,
+		},
+		{
+			.path = dir_s2d2,
+			.access = ACCESS_RO,
+		},
+		{}
+	};
+	int dirfd;
+	const int ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
+
+	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_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(layout1, relative_open)
+{
+	test_relative_path(_metadata, REL_OPEN);
+}
+
+TEST_F(layout1, relative_chdir)
+{
+	test_relative_path(_metadata, REL_CHDIR);
+}
+
+TEST_F(layout1, relative_chroot_only)
+{
+	test_relative_path(_metadata, REL_CHROOT_ONLY);
+}
+
+TEST_F(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 char *const path, const int ret)
+{
+	int status;
+	char *const argv[] = {(char *)path, NULL};
+	const pid_t child = fork();
+
+	ASSERT_LE(0, child);
+	if (child == 0) {
+		ASSERT_EQ(ret, execve(path, argv, NULL)) {
+			TH_LOG("Failed to execute \"%s\": %s", path,
+					strerror(errno));
+		};
+		ASSERT_EQ(EACCES, errno);
+		_exit(_metadata->passed ? 2 : 1);
+		return;
+	}
+	ASSERT_EQ(child, waitpid(child, &status, 0));
+	ASSERT_EQ(1, WIFEXITED(status));
+	ASSERT_EQ(ret ? 2 : 0, WEXITSTATUS(status)) {
+		TH_LOG("Unexpected return code for \"%s\": %s", path,
+				strerror(errno));
+	};
+}
+
+TEST_F(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));
+
+	test_execute(_metadata, file1_s1d1, -1);
+	test_execute(_metadata, file1_s1d2, 0);
+	test_execute(_metadata, file1_s1d3, 0);
+}
+
+TEST_F(layout1, link)
+{
+	const struct rule rules[] = {
+		{
+			.path = dir_s1d2,
+			.access = LANDLOCK_ACCESS_FS_MAKE_REG,
+		},
+		{}
+	};
+	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));
+
+	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(EACCES, errno);
+	ASSERT_EQ(-1, link(file2_s1d2, file1_s1d3));
+	ASSERT_EQ(EACCES, errno);
+
+	ASSERT_EQ(0, link(file2_s1d2, file1_s1d2)) {
+		TH_LOG("Failed to link file to \"%s\": %s", file2_s1d2,
+				strerror(errno));
+	};
+	ASSERT_EQ(0, link(file2_s1d3, file1_s1d3));
+}
+
+TEST_F(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_s1d1));
+	ASSERT_EQ(0, unlink(file1_s1d2));
+
+	enforce_ruleset(_metadata, ruleset_fd);
+	ASSERT_EQ(0, close(ruleset_fd));
+
+	/* Replaces file. */
+	ASSERT_EQ(-1, rename(file1_s2d3, file1_s1d3));
+	ASSERT_EQ(EACCES, errno);
+	ASSERT_EQ(-1, rename(file1_s2d1, file1_s1d3));
+	ASSERT_EQ(EACCES, errno);
+	/* Same parent. */
+	ASSERT_EQ(0, rename(file2_s2d3, file1_s2d3)) {
+		TH_LOG("Failed to rename file \"%s\": %s", file2_s2d3,
+				strerror(errno));
+	};
+
+	/* Renames files. */
+	ASSERT_EQ(-1, rename(file1_s2d2, file1_s1d2));
+	ASSERT_EQ(EACCES, errno);
+	ASSERT_EQ(0, unlink(file1_s1d3));
+	ASSERT_EQ(-1, rename(file1_s2d1, file1_s1d3));
+	ASSERT_EQ(EACCES, errno);
+	/* Same parent. */
+	ASSERT_EQ(0, rename(file2_s1d3, file1_s1d3));
+}
+
+TEST_F(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. */
+	ASSERT_EQ(0, unlink(file1_s1d3));
+	ASSERT_EQ(0, unlink(file2_s1d3));
+
+	enforce_ruleset(_metadata, ruleset_fd);
+	ASSERT_EQ(0, close(ruleset_fd));
+
+	/* Renames directory. */
+	ASSERT_EQ(-1, rename(dir_s2d3, dir_s1d3));
+	ASSERT_EQ(EACCES, errno);
+	ASSERT_EQ(0, unlink(file1_s1d2));
+	ASSERT_EQ(0, rename(dir_s1d3, file1_s1d2)) {
+		TH_LOG("Failed to rename directory \"%s\": %s", dir_s1d3,
+				strerror(errno));
+	};
+	ASSERT_EQ(0, rmdir(file1_s1d2));
+}
+
+TEST_F(layout1, rmdir)
+{
+	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));
+	/* dir_s1d2 itself cannot be removed. */
+	ASSERT_EQ(-1, rmdir(dir_s1d2));
+	ASSERT_EQ(EACCES, errno);
+	ASSERT_EQ(-1, rmdir(dir_s1d1));
+	ASSERT_EQ(EACCES, errno);
+}
+
+TEST_F(layout1, unlink)
+{
+	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(0, unlink(file1_s1d2)) {
+		TH_LOG("Failed to unlink file \"%s\": %s", file1_s1d2,
+				strerror(errno));
+	};
+	ASSERT_EQ(0, unlink(file1_s1d3));
+}
+
+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);
+
+	unlink(file1_s1d1);
+	unlink(file1_s1d2);
+	unlink(file1_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(0, mknod(file1_s1d2, mode | 0400, dev)) {
+		TH_LOG("Failed to make file \"%s\": %s",
+				file1_s1d2, strerror(errno));
+	};
+	ASSERT_EQ(0, mknod(file1_s1d3, mode | 0400, dev));
+}
+
+TEST_F(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(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(layout1, make_reg)
+{
+	test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_REG, S_IFREG, 0);
+	test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_REG, 0, 0);
+}
+
+TEST_F(layout1, make_sock)
+{
+	test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_SOCK, S_IFSOCK, 0);
+}
+
+TEST_F(layout1, make_fifo)
+{
+	test_make_file(_metadata, LANDLOCK_ACCESS_FS_MAKE_FIFO, S_IFIFO, 0);
+}
+
+TEST_F(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(file1_s1d2));
+	ASSERT_EQ(0, unlink(file1_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(0, symlink("none", file1_s1d2)) {
+		TH_LOG("Failed to make symlink \"%s\": %s",
+				file1_s1d2, strerror(errno));
+	};
+	ASSERT_EQ(0, symlink("none", file1_s1d3));
+}
+
+TEST_F(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)) {
+		TH_LOG("Failed to make directory \"%s\": %s",
+				file1_s1d2, strerror(errno));
+	};
+	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(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(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]));
+}
+
+TEST(cleanup)
+{
+	cleanup_layout1(_metadata);
+}
+
+TEST_HARNESS_MAIN