From: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx> This is an adaptation of https://www.kernel.org/doc/html/v5.13/userspace-api/landlock.html Signed-off-by: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210730144116.332091-3-mic@xxxxxxxxxxx --- Changes since v2: * Fix syscall signature (attr pointer). * Add an EXAMPLES section referring to landlock(7). * Change list order in the SEE ALSO section. * Fix .IR and .BR use as explained by Alejandro Colomar. Changes since v1: * Replace all ".I" with ".IR", except when used for titles. * Append punctuation to ".IR" and ".BR" when it makes sense (requested by Alejandro Colomar). * Cut lines according to the semantic newline rules (requested by Alejandro Colomar). * Remove roman style from ".TP" section titles (requested by Alejandro Colomar). * Add comma after "i.e." and "e.g.". * Add a "CONFORMING TO" section. * Replace "(2)" with "()" for the described syscall name. --- man2/landlock_create_ruleset.2 | 139 +++++++++++++++++++++++++++++++++ 1 file changed, 139 insertions(+) create mode 100644 man2/landlock_create_ruleset.2 diff --git a/man2/landlock_create_ruleset.2 b/man2/landlock_create_ruleset.2 new file mode 100644 index 000000000000..e1ca4bcf8c86 --- /dev/null +++ b/man2/landlock_create_ruleset.2 @@ -0,0 +1,139 @@ +.\" Copyright © 2017-2020 Mickaël Salaün <mic@xxxxxxxxxxx> +.\" Copyright © 2019-2020 ANSSI +.\" Copyright © 2021 Microsoft Corporation +.\" +.\" %%%LICENSE_START(VERBATIM) +.\" Permission is granted to make and distribute verbatim copies of this +.\" manual provided the copyright notice and this permission notice are +.\" preserved on all copies. +.\" +.\" Permission is granted to copy and distribute modified versions of this +.\" manual under the conditions for verbatim copying, provided that the +.\" entire resulting derived work is distributed under the terms of a +.\" permission notice identical to this one. +.\" +.\" Since the Linux kernel and libraries are constantly changing, this +.\" manual page may be incorrect or out-of-date. The author(s) assume no +.\" responsibility for errors or omissions, or for damages resulting from +.\" the use of the information contained herein. The author(s) may not +.\" have taken the same level of care in the production of this manual, +.\" which is licensed free of charge, as they might when working +.\" professionally. +.\" +.\" Formatted or processed versions of this manual, if unaccompanied by +.\" the source, must acknowledge the copyright and authors of this work. +.\" %%%LICENSE_END +.\" +.TH LANDLOCK_CREATE_RULESET 2 2021-06-27 Linux "Linux Programmer's Manual" +.SH NAME +landlock_create_ruleset \- create a new Landlock ruleset +.SH SYNOPSIS +.nf +.BR "#include <linux/landlock.h>" " /* Definition of " LANDLOCK_* " constants */" +.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" +.PP +.BI "int syscall(SYS_landlock_create_ruleset, +.BI " const struct landlock_ruleset_attr *" attr , +.BI " size_t " size " , __u32 " flags ); +.SH DESCRIPTION +A Landlock ruleset identifies a set of rules (i.e., actions on objects). +This +.BR landlock_create_ruleset () +system call enables creating a new file descriptor identifying a ruleset. +This file descriptor can then be used by +.BR landlock_add_rule (2) +and +.BR landlock_restrict_self (2). +See +.BR landlock (7) +for a global overview. +.PP +.I attr +specifies the properties of the new ruleset. +It points to the following structure: +.IP +.in +4n +.EX +struct landlock_ruleset_attr { + __u64 handled_access_fs; +}; +.EE +.in +.IP +.I handled_access_fs +is a bitmask of actions that is handled by this ruleset and should then be +forbidden if no rule explicitly allow them +(see +.B Filesystem actions +in +.BR landlock (7)). +This enables simply restricting ambient rights +(e.g., global filesystem access) and is needed for compatibility reasons. +.PP +.I size +must be specified as +.I sizeof(struct landlock_ruleset_attr) +for compatibility reasons. +.PP +.I flags +must be 0 if +.I attr +is used. +Otherwise, +.I flags +can be set to: +.TP +.B LANDLOCK_CREATE_RULESET_VERSION +If +.I attr +is NULL and +.I size +is 0, then the returned value is the highest supported Landlock ABI version +(starting at 1). +This version can be used for a best-effort security approach, +which is encouraged when user space is not pinned to a specific kernel +version. +All features documented in these man pages are available with the version +1. +.SH RETURN VALUE +On success, +.BR landlock_create_ruleset () +returns a new Landlock ruleset file descriptor, or a Landlock ABI version +according to +.IR flags . +.SH ERRORS +.BR landlock_create_ruleset () +can failed for the following reasons: +.TP +.B EOPNOTSUPP +Landlock is supported by the kernel but disabled at boot time. +.TP +.B EINVAL +Unknown +.IR flags , +or unknown access, or too small +.IR size . +.TP +.B E2BIG +.I size +is too big. +.TP +.B EFAULT +.I attr +was not a valid address. +.TP +.B ENOMSG +Empty accesses (i.e., +.I attr->handled_access_fs +is 0). +.SH VERSIONS +Landlock was added in Linux 5.13. +.SH CONFORMING TO +This system call is Linux-specific. +.SH EXAMPLES +See +.BR landlock (7). +.SH SEE ALSO +.BR landlock_add_rule (2), +.BR landlock_restrict_self (2), +.BR landlock (7) -- 2.32.0
