From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-bc0e.mail.infomaniak.ch (smtp-bc0e.mail.infomaniak.ch [45.157.188.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C1722EBB8C for ; Thu, 23 Apr 2026 13:51:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.157.188.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776952303; cv=none; b=SHH0pPKVFflnoTXu6CPm+VxrKjlTXXcCcoGkfnwy6jK058yRQScd3sYoZHPqRFj3NUKOXgyraGZK+f7acXxVMoR6FejYBOWjZqvirgEXao+9qpEafn1PXAORcG0OYk2sWCcsnAHHF3RexQgPw7iCiLQfmDKvW3wQrHzpUhPoFIo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776952303; c=relaxed/simple; bh=Nx8vgo2Lltv8IcAMFyw70WeOqVo1vutN4YIGZ3ssa0c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ajmJ6Xi+vH8IFTqfBqENy1f2+U2W95vRSfDn+orom0DG/aXDBZlE0GLYRwTYgL0TnN9q7Y6yxhprZO/3zI24i4FgN1oZEGQooBTDwp+iKCMmBFKoyittEEwzDoEgFKKjIaXuSUz9yKsbJVcJqdpzPrfXKRveaOSj0p9XwwyW4bE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=digikod.net; spf=pass smtp.mailfrom=digikod.net; dkim=pass (1024-bit key) header.d=digikod.net header.i=@digikod.net header.b=C+Ojn9n5; arc=none smtp.client-ip=45.157.188.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=digikod.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=digikod.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=digikod.net header.i=@digikod.net header.b="C+Ojn9n5" Received: from smtp-3-0001.mail.infomaniak.ch (smtp-3-0001.mail.infomaniak.ch [10.4.36.108]) by smtp-3-3000.mail.infomaniak.ch (Postfix) with ESMTPS id 4g1cvV28fvz7B0; Thu, 23 Apr 2026 15:51:34 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=digikod.net; s=20191114; t=1776952294; bh=1VlQY6hUujaQa04QtuuAKMaQ47V5EZuWHUs9YoaKa4k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=C+Ojn9n5dFHGQAg8y//KY9TqhMK/NDTf1ave9jO7aFnzlIzNNXGc46S8aTNB2b5Tl C7RXENCCtpHh/6sRASanpmFI3m4ncpQ4id62rh9+ezaBMCx6Cv4c4S4ZoAY+zwkIWq sONEmO6IGnfunef/salxz+DN7op0Ce9gae7ooe18= Received: from unknown by smtp-3-0001.mail.infomaniak.ch (Postfix) with ESMTPA id 4g1cvT3fkszsw2; Thu, 23 Apr 2026 15:51:33 +0200 (CEST) Date: Thu, 23 Apr 2026 15:51:32 +0200 From: =?utf-8?Q?Micka=C3=ABl_Sala=C3=BCn?= To: Justin Suess Cc: Christian Brauner , =?utf-8?Q?G=C3=BCnther?= Noack , Paul Moore , "Serge E . Hallyn" , Lennart Poettering , Mikhail Ivanov , Nicolas Bouchinet , Shervin Oloumi , Tingmao Wang , kernel-team@cloudflare.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: Re: [RFC PATCH v1 11/11] landlock: Add documentation for capability and namespace restrictions Message-ID: <20260423.xai2Pe3theiw@digikod.net> References: <20260312100444.2609563-1-mic@digikod.net> <20260312100444.2609563-12-mic@digikod.net> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Infomaniak-Routing: alpha On Thu, Mar 12, 2026 at 10:48:42AM -0400, Justin Suess wrote: > On Thu, Mar 12, 2026 at 11:04:44AM +0100, Mickaël Salaün wrote: > > Document the two new Landlock permission categories in the userspace > > API guide, admin guide, and kernel security documentation. > > > > The userspace API guide adds sections on capability restriction > > (LANDLOCK_PERM_CAPABILITY_USE with LANDLOCK_RULE_CAPABILITY), namespace > > restriction (LANDLOCK_PERM_NAMESPACE_ENTER with LANDLOCK_RULE_NAMESPACE > > covering creation via unshare/clone and entry via setns), and the > > backward-compatible degradation pattern for ABI < 9. A table documents > > the per-namespace-type capability requirements for both creation and > > entry. > > > > The admin guide adds the new perm.namespace_enter and > > perm.capability_use audit blocker names with their object identification > > fields (namespace_type, namespace_inum, capability). > > > > The kernel security documentation adds a "Ruleset restriction models" > > section defining the three models (handled_access_*, handled_perm, > > scoped), their coverage and compatibility properties, and the criteria > > for choosing between them for future features. It also documents > > composability with user namespaces and adds kernel-doc references for > > the new capability and namespace headers. > > > > Cc: Christian Brauner > > Cc: Günther Noack > > Cc: Paul Moore > > Cc: Serge E. Hallyn > > Signed-off-by: Mickaël Salaün > > --- > > Documentation/admin-guide/LSM/landlock.rst | 19 ++- > > Documentation/security/landlock.rst | 80 ++++++++++- > > Documentation/userspace-api/landlock.rst | 156 ++++++++++++++++++++- > > 3 files changed, 245 insertions(+), 10 deletions(-) > > > > diff --git a/Documentation/admin-guide/LSM/landlock.rst b/Documentation/admin-guide/LSM/landlock.rst > > index 9923874e2156..99c6a599ce9e 100644 > > --- a/Documentation/admin-guide/LSM/landlock.rst > > +++ b/Documentation/admin-guide/LSM/landlock.rst > > @@ -6,7 +6,7 @@ Landlock: system-wide management > > ================================ > > > > :Author: Mickaël Salaün > > -:Date: January 2026 > > +:Date: March 2026 > > > > Landlock can leverage the audit framework to log events. > > > > @@ -59,14 +59,25 @@ AUDIT_LANDLOCK_ACCESS > > - scope.abstract_unix_socket - Abstract UNIX socket connection denied > > - scope.signal - Signal sending denied > > > > + **perm.*** - Permission restrictions (ABI 9+): > > + - perm.namespace_enter - Namespace entry was denied (creation via > > + :manpage:`unshare(2)` / :manpage:`clone(2)` or joining via > > + :manpage:`setns(2)`); > > + ``namespace_type`` indicates the type (hex CLONE_NEW* bitmask), > > + ``namespace_inum`` identifies the target namespace for > > + :manpage:`setns(2)` operations > > + - perm.capability_use - Capability use was denied; > > + ``capability`` indicates the capability number > > + > > Multiple blockers can appear in a single event (comma-separated) when > > multiple access rights are missing. For example, creating a regular file > > in a directory that lacks both ``make_reg`` and ``refer`` rights would show > > ``blockers=fs.make_reg,fs.refer``. > > > > - The object identification fields (path, dev, ino for filesystem; opid, > > - ocomm for signals) depend on the type of access being blocked and provide > > - context about what resource was involved in the denial. > > + The object identification fields depend on the type of access being blocked: > > + ``path``, ``dev``, ``ino`` for filesystem; ``opid``, ``ocomm`` for signals; > > + ``namespace_type`` and ``namespace_inum`` for namespace operations; > > + ``capability`` for capability use. > > > > > > AUDIT_LANDLOCK_DOMAIN > > diff --git a/Documentation/security/landlock.rst b/Documentation/security/landlock.rst > > index 3e4d4d04cfae..cd3d640ca5c9 100644 > > --- a/Documentation/security/landlock.rst > > +++ b/Documentation/security/landlock.rst > > @@ -7,7 +7,7 @@ Landlock LSM: kernel documentation > > ================================== > > > > :Author: Mickaël Salaün > > -:Date: September 2025 > > +:Date: March 2026 > > > > Landlock's goal is to create scoped access-control (i.e. sandboxing). To > > harden a whole system, this feature should be available to any process, > > @@ -89,6 +89,72 @@ this is required to keep access controls consistent over the whole system, and > > this avoids unattended bypasses through file descriptor passing (i.e. confused > > deputy attack). > > > > +Composability with user namespaces > > +---------------------------------- > > + > > +Landlock domain-based scoping and the kernel's user namespace-based capability > > +scoping enforce isolation over independent hierarchies. Landlock checks domain > > +ancestry; the kernel's ``ns_capable()`` checks user namespace ancestry. These > > +hierarchies are orthogonal: Landlock enforcement is deterministic with respect > > +to its own configuration, regardless of namespace or capability state, and vice > > +versa. This orthogonality is a design invariant that must hold for all new > > +scoped features. > The last sentence on orthogonality may better belong under the restriction > model section for scoped access rights. I assume that future scopes must > also be deterministic with respect to landlock's configuration as well, > not just user namespaces. Correct > > + > > +Ruleset restriction models > > +-------------------------- > +1 > > This section is very helpful for aligning new features with a particular > model. Thanks > > > + > > +Landlock provides three restriction models, each with different coverage > > +and compatibility properties. > Maybe add: > > Each restriction model below corresponds to one or more fields of > ``struct landlock_ruleset_attr``. Ok > > > + > > +Access rights (``handled_access_*``) > > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > + > > +Access rights control **enumerated operations on kernel objects** > > +identified by a rule key (a file hierarchy or a network port). Each > > +``handled_access_*`` field declares a set of access rights that the > > +ruleset restricts. Multiple access rights share a single rule type. > > +Operations for which no access right exists yet remain uncontrolled; > > +new rights are added incrementally across ABI versions. > > + > > +Permissions (``handled_perm``) > > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > + > > +Permissions control **broad operations enforced at single kernel > > +chokepoints**, achieving complete deny-by-default coverage. Each > > +``LANDLOCK_PERM_*`` flag maps to its own rule type. When a ruleset > > +handles a permission, all instances of that operation are denied unless > > +explicitly allowed by a rule. New kernel values (new ``CAP_*`` > > +capabilities, new ``CLONE_NEW*`` namespace types) are automatically > > +denied without any Landlock update. > > + > > +Each permission flag names a single gateway operation whose control > > +transitively covers an open-ended set of downstream operations: for > > +example, exercising a capability enables privileged operations across > > +many subsystems; entering a namespace enables gaining capabilities in a > > +new context. > > + > > +Permission rules identify what to allow using constants defined by other > > +kernel subsystems (``CAP_*``, ``CLONE_NEW*``). Unknown values are > > +silently ignored because deny-by-default ensures they are denied anyway. > > +In contrast, unknown ``LANDLOCK_PERM_*`` flags in ``handled_perm`` are > > +rejected (``-EINVAL``), since Landlock owns that namespace. > > + > > +Scopes (``scoped``) > > +~~~~~~~~~~~~~~~~~~~~ > > + > > +Scopes restrict **cross-domain interactions** categorically, without > > +rules. Setting a scope flag (e.g. ``LANDLOCK_SCOPE_SIGNAL``) denies the > > +operation to targets outside the Landlock domain or its children. Like > > +permissions, scopes provide complete coverage of the controlled > > +operation. > > + > > +When adding new Landlock features, new operations on existing rule types > > +extend the corresponding ``handled_access_*`` field (e.g. a new > > +filesystem operation extends ``handled_access_fs``). A new object > > +category with multiple fine-grained operations would use a new > > +``handled_access_*`` field. New rule types that control a single > > +chokepoint operation use ``handled_perm``. > > + > > Tests > > ===== > > > > @@ -110,6 +176,18 @@ Filesystem > > .. kernel-doc:: security/landlock/fs.h > > :identifiers: > > > > +Namespace > > +--------- > > + > > +.. kernel-doc:: security/landlock/ns.h > > + :identifiers: > > + > > +Capability > > +---------- > > + > > +.. kernel-doc:: security/landlock/cap.h > > + :identifiers: > > + > > Process credential > > ------------------ > > > > diff --git a/Documentation/userspace-api/landlock.rst b/Documentation/userspace-api/landlock.rst > > index 13134bccdd39..238d30a18162 100644 > > --- a/Documentation/userspace-api/landlock.rst > > +++ b/Documentation/userspace-api/landlock.rst > > @@ -8,7 +8,7 @@ Landlock: unprivileged access control > > ===================================== > > > > :Author: Mickaël Salaün > > -:Date: January 2026 > > +:Date: March 2026 > > > > The goal of Landlock is to enable restriction of ambient rights (e.g. global > > filesystem or network access) for a set of processes. Because Landlock > > @@ -33,7 +33,7 @@ A Landlock rule describes an action on an object which the process intends to > > perform. A set of rules is aggregated in a ruleset, which can then restrict > > the thread enforcing it, and its future children. > > > > -The two existing types of rules are: > > +The existing types of rules are: > > > > Filesystem rules > > For these rules, the object is a file hierarchy, > > @@ -44,6 +44,14 @@ Network rules (since ABI v4) > > For these rules, the object is a TCP port, > > and the related actions are defined with `network access rights`. > > > > +Capability rules (since ABI v9) > > + For these rules, the object is a set of Linux capabilities, > > + and the related actions are defined with `permission flags`. > > + > > +Namespace rules (since ABI v9) > > + For these rules, the object is a set of namespace types, > > + and the related actions are defined with `permission flags`. > > + > > Defining and enforcing a security policy > > ---------------------------------------- > > > > @@ -84,6 +92,9 @@ to be explicit about the denied-by-default access rights. > > .scoped = > > LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET | > > LANDLOCK_SCOPE_SIGNAL, > > + .handled_perm = > > + LANDLOCK_PERM_CAPABILITY_USE | > > + LANDLOCK_PERM_NAMESPACE_ENTER, > > }; > > > > Because we may not know which kernel version an application will be executed > > @@ -127,6 +138,12 @@ version, and only use the available subset of access rights: > > /* Removes LANDLOCK_SCOPE_* for ABI < 6 */ > > ruleset_attr.scoped &= ~(LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET | > > LANDLOCK_SCOPE_SIGNAL); > > + __attribute__((fallthrough)); > > + case 6: > > + case 7: > > + case 8: > > + /* Removes permission support for ABI < 9 */ > > + ruleset_attr.handled_perm = 0; > > } > > > > This enables the creation of an inclusive ruleset that will contain our rules. > > @@ -191,6 +208,42 @@ number for a specific action: HTTPS connections. > > err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT, > > &net_port, 0); > > > > +For capability access-control, we can add rules that allow specific > > +capabilities. For instance, to allow ``CAP_SYS_CHROOT`` (so the sandboxed > > +process can call :manpage:`chroot(2)` inside a user namespace): > > + > > +.. code-block:: c > > + > > + struct landlock_capability_attr cap_attr = { > > + .allowed_perm = LANDLOCK_PERM_CAPABILITY_USE, > > + .capabilities = (1ULL << CAP_SYS_CHROOT), > > + }; > > + > > + err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_CAPABILITY, > > + &cap_attr, 0); > > + > > +For namespace access-control, we can add rules that allow entering specific > > +namespace types (creating them via :manpage:`unshare(2)` / :manpage:`clone(2)` > > +or joining them via :manpage:`setns(2)`). For instance, to allow creating user > > +namespaces (which grants all capabilities inside the new namespace): > > + > > +.. code-block:: c > > + > > + struct landlock_namespace_attr ns_attr = { > > + .allowed_perm = LANDLOCK_PERM_NAMESPACE_ENTER, > > + .namespace_types = CLONE_NEWUSER, > > + }; > > + > > + err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NAMESPACE, > > + &ns_attr, 0); > > + > > +Together, these two rules allow an unprivileged process to create a user > > +namespace and call :manpage:`chroot(2)` inside it, while denying all other > > +capabilities and namespace types. User namespace creation is the one operation > > +that does not require ``CAP_SYS_ADMIN``, so no capability rule is needed for it. > > +See `Capability and namespace restrictions`_ for details on capability > > +requirements. > > + > > When passing a non-zero ``flags`` argument to ``landlock_restrict_self()``, a > > similar backwards compatibility check is needed for the restrict flags > > (see sys_landlock_restrict_self() documentation for available flags): > > @@ -354,10 +407,87 @@ The operations which can be scoped are: > > A :manpage:`sendto(2)` on a socket which was previously connected will not > > be restricted. This works for both datagram and stream sockets. > > > > -IPC scoping does not support exceptions via :manpage:`landlock_add_rule(2)`. > > +Scoping does not support exceptions via :manpage:`landlock_add_rule(2)`. > > If an operation is scoped within a domain, no rules can be added to allow access > > to resources or processes outside of the scope. > > > > +Capability and namespace restrictions > > +------------------------------------- > > + > > +See Documentation/security/landlock.rst for the design rationale behind > > +the permission model (``handled_perm``) and how it differs from access > > +rights (``handled_access_*``) and scopes (``scoped``). > > +When a process creates a user namespace, the kernel grants all capabilities > > +within that namespace. While these capabilities cannot directly bypass Landlock > > +restrictions (Landlock enforces access controls independently of capability > > +checks), they open kernel code paths that are normally unreachable to > > +unprivileged users and may contain exploitable bugs. > > + > > +Landlock provides two complementary permissions to address this. > > +``LANDLOCK_PERM_CAPABILITY_USE`` restricts which capabilities a process can use, > > +even when it holds them. ``LANDLOCK_PERM_NAMESPACE_ENTER`` restricts which > > +namespace types a process can create (via :manpage:`unshare(2)` or > > +:manpage:`clone(2)`) or join (via :manpage:`setns(2)`). After creating a user > > +namespace, the granted capabilities are scoped to namespaces owned by that user > > +namespace or its descendants; to exercise a capability such as > > +``CAP_NET_ADMIN``, the process must create a namespace of the corresponding type > > +(e.g., a network namespace). Configuring both permissions together provides > > +full coverage: ``LANDLOCK_PERM_CAPABILITY_USE`` restricts which capabilities are > > +available, while ``LANDLOCK_PERM_NAMESPACE_ENTER`` restricts the namespaces in > > +which they can be used. > Maybe add a section on the what this does versus PR_SET_NO_NEW_PRIVS. Hmm, what do you mean? What would be the link with this part? > > The difference might be obvious to people familiar with namespaces and > capabilities, but not to many users less familiar with the subject. > > I could see users using the LANDLOCK_PERM_* flags erroneously > assuming that LANDLOCK_PERM_CAPABILITY_USE is required to restrict gaining of > new capabilities through execve(), (ie through setuid) when in fact this is > already restricted if nnp is set. What would be the issue if no rule allow capabilities? The most handled_* or scoped bits are set, the better. > > Some clarification on this would be helpful here or where > PR_SET_NO_NEW_PRIVS is discussed in the Landlock docs. Ok, I'll try to add something about NNP. > > + > > +When a Landlock domain handles ``LANDLOCK_PERM_CAPABILITY_USE``, all Linux > > +:manpage:`capabilities(7)` are denied by default unless a rule explicitly allows > Nit: > > all Linux :manpage:`capabilities(7)` > > might be better as > > the exercise of all Linux :manpage:`capabilities(7)` Indeed > > Since as pointed out before we do not restrict their precense, but their > exercise. > > +them. This is purely restrictive: Landlock can only deny capabilities that the > > +traditional capability mechanism would have allowed, never grant additional ones. > > +Rules are added with ``LANDLOCK_RULE_CAPABILITY`` using a > > +&struct landlock_capability_attr. Each rule specifies a set of ``CAP_*`` values > > +(as a bitmask) to allow. Capabilities above ``CAP_LAST_CAP`` are silently > > +accepted but have no effect since the kernel never checks them; this means new > > +capabilities introduced by future kernels are automatically denied. > > + > > +When a Landlock domain handles ``LANDLOCK_PERM_NAMESPACE_ENTER``, namespace > > +creation and entry are denied by default unless a rule explicitly allows them. > > +Rules are added with ``LANDLOCK_RULE_NAMESPACE`` using a > > +&struct landlock_namespace_attr. Each rule specifies a set of ``CLONE_NEW*`` > > +flags to allow. > > + > > +In practice, unprivileged processes first create a user namespace (which requires > > +no capability and grants all capabilities within it), then use those capabilities > > +to create other namespace types. All non-user namespace types require > > +``CAP_SYS_ADMIN`` for both creation and :manpage:`setns(2)` entry; mount > > +namespace entry additionally requires ``CAP_SYS_CHROOT``. For > > +:manpage:`setns(2)`, capabilities are checked relative to the target namespace, > > +so a process in an ancestor user namespace naturally satisfies them; this > > +includes joining user namespaces, which requires ``CAP_SYS_ADMIN``. When > > +``LANDLOCK_PERM_CAPABILITY_USE`` is also handled, each of these capabilities > > +must be explicitly allowed by a rule. > > + > > +When combining ``CLONE_NEWUSER`` with other ``CLONE_NEW*`` flags in a single > > +:manpage:`unshare(2)` call, the ``CAP_SYS_ADMIN`` check targets the newly > > +created user namespace, which is handled by ``LANDLOCK_PERM_NAMESPACE_ENTER`` > > +independently from ``LANDLOCK_PERM_CAPABILITY_USE``. Performing the user > > +namespace creation and the additional namespace creation in two separate > > +:manpage:`unshare(2)` calls requires a rule allowing ``CAP_SYS_ADMIN`` if the > > +domain also handles ``LANDLOCK_PERM_CAPABILITY_USE``. > > + > > +More generally, Landlock domains and user namespaces form independent > > +hierarchies: Landlock domains restrict what actions are allowed (each stacked > > +layer narrows the permitted set), while user namespaces restrict where > > +capabilities take effect (only within the process's own namespace and its > > +descendants). Landlock access controls are fully determined by the domain > > +configuration, regardless of the process's position in the user namespace > > +hierarchy. When creating child user namespaces, it is recommended to also > > +create a dedicated Landlock domain with restrictions relevant to each namespace > > +context. > > + > > +Note that ``LANDLOCK_PERM_CAPABILITY_USE`` restricts the *use* of capabilities, > > +not their presence in the process's credential. Capability sets can change > > +after a domain is enforced through user namespace entry, :manpage:`execve(2)` of > > +binaries with file capabilities, or :manpage:`capset(2)`. In all cases, > > +:manpage:`capget(2)` will report the credential's capability sets, but any > > +denied capability will fail with ``EPERM`` when exercised. > > + > > Truncating files > > ---------------- > > > > @@ -515,7 +645,7 @@ Access rights > > ------------- > > > > .. kernel-doc:: include/uapi/linux/landlock.h > > - :identifiers: fs_access net_access scope > > + :identifiers: fs_access net_access scope perm > > > > Creating a new ruleset > > ---------------------- > > @@ -534,7 +664,8 @@ Extending a ruleset > > > > .. kernel-doc:: include/uapi/linux/landlock.h > > :identifiers: landlock_rule_type landlock_path_beneath_attr > > - landlock_net_port_attr > > + landlock_net_port_attr landlock_capability_attr > > + landlock_namespace_attr > > > > Enforcing a ruleset > > ------------------- > > @@ -685,6 +816,21 @@ enforce Landlock rulesets across all threads of the calling process > > using the ``LANDLOCK_RESTRICT_SELF_TSYNC`` flag passed to > > sys_landlock_restrict_self(). > > > > +Capability restriction (ABI < 9) > > +-------------------------------- > > + > > +Starting with the Landlock ABI version 9, it is possible to restrict > > +:manpage:`capabilities(7)` with the new ``LANDLOCK_PERM_CAPABILITY_USE`` > > +permission flag and ``LANDLOCK_RULE_CAPABILITY`` rule type. > > + > > +Namespace restriction (ABI < 9) > > +------------------------------- > > + > > +Starting with the Landlock ABI version 9, it is possible to restrict > > +namespace creation (:manpage:`unshare(2)`, :manpage:`clone(2)`) and entry > > +(:manpage:`setns(2)`) with the new ``LANDLOCK_PERM_NAMESPACE_ENTER`` permission > > +flag and ``LANDLOCK_RULE_NAMESPACE`` rule type. > > + > > .. _kernel_support: > > > > Kernel support > > -- > > 2.53.0 > > >