LSM: add SafeSetID module that gates setid calls
SafeSetID gates the setid family of syscalls to restrict UID/GID
transitions from a given UID/GID to only those approved by a
system-wide whitelist. These restrictions also prohibit the given
UIDs/GIDs from obtaining auxiliary privileges associated with
CAP_SET{U/G}ID, such as allowing a user to set up user namespace UID
mappings. For now, only gating the set*uid family of syscalls is
supported, with support for set*gid coming in a future patch set.
Signed-off-by: Micah Morton <mortonm@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
This commit is contained in:
Micah Morton
James Morris
Родитель
40852275a9
Коммит
aeca4e2ca6
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@ -0,0 +1,107 @@
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=========
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SafeSetID
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=========
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SafeSetID is an LSM module that gates the setid family of syscalls to restrict
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UID/GID transitions from a given UID/GID to only those approved by a
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system-wide whitelist. These restrictions also prohibit the given UIDs/GIDs
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from obtaining auxiliary privileges associated with CAP_SET{U/G}ID, such as
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allowing a user to set up user namespace UID mappings.
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Background
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==========
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In absence of file capabilities, processes spawned on a Linux system that need
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to switch to a different user must be spawned with CAP_SETUID privileges.
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CAP_SETUID is granted to programs running as root or those running as a non-root
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user that have been explicitly given the CAP_SETUID runtime capability. It is
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often preferable to use Linux runtime capabilities rather than file
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capabilities, since using file capabilities to run a program with elevated
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privileges opens up possible security holes since any user with access to the
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file can exec() that program to gain the elevated privileges.
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While it is possible to implement a tree of processes by giving full
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CAP_SET{U/G}ID capabilities, this is often at odds with the goals of running a
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tree of processes under non-root user(s) in the first place. Specifically,
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since CAP_SETUID allows changing to any user on the system, including the root
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user, it is an overpowered capability for what is needed in this scenario,
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especially since programs often only call setuid() to drop privileges to a
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lesser-privileged user -- not elevate privileges. Unfortunately, there is no
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generally feasible way in Linux to restrict the potential UIDs that a user can
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switch to through setuid() beyond allowing a switch to any user on the system.
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This SafeSetID LSM seeks to provide a solution for restricting setid
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capabilities in such a way.
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The main use case for this LSM is to allow a non-root program to transition to
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other untrusted uids without full blown CAP_SETUID capabilities. The non-root
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program would still need CAP_SETUID to do any kind of transition, but the
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additional restrictions imposed by this LSM would mean it is a "safer" version
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of CAP_SETUID since the non-root program cannot take advantage of CAP_SETUID to
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do any unapproved actions (e.g. setuid to uid 0 or create/enter new user
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namespace). The higher level goal is to allow for uid-based sandboxing of system
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services without having to give out CAP_SETUID all over the place just so that
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non-root programs can drop to even-lesser-privileged uids. This is especially
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relevant when one non-root daemon on the system should be allowed to spawn other
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processes as different uids, but its undesirable to give the daemon a
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basically-root-equivalent CAP_SETUID.
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Other Approaches Considered
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===========================
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Solve this problem in userspace
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-------------------------------
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For candidate applications that would like to have restricted setid capabilities
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as implemented in this LSM, an alternative option would be to simply take away
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setid capabilities from the application completely and refactor the process
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spawning semantics in the application (e.g. by using a privileged helper program
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to do process spawning and UID/GID transitions). Unfortunately, there are a
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number of semantics around process spawning that would be affected by this, such
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as fork() calls where the program doesn???t immediately call exec() after the
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fork(), parent processes specifying custom environment variables or command line
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args for spawned child processes, or inheritance of file handles across a
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fork()/exec(). Because of this, as solution that uses a privileged helper in
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userspace would likely be less appealing to incorporate into existing projects
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that rely on certain process-spawning semantics in Linux.
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Use user namespaces
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-------------------
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Another possible approach would be to run a given process tree in its own user
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namespace and give programs in the tree setid capabilities. In this way,
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programs in the tree could change to any desired UID/GID in the context of their
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own user namespace, and only approved UIDs/GIDs could be mapped back to the
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initial system user namespace, affectively preventing privilege escalation.
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Unfortunately, it is not generally feasible to use user namespaces in isolation,
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without pairing them with other namespace types, which is not always an option.
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Linux checks for capabilities based off of the user namespace that ???owns??? some
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entity. For example, Linux has the notion that network namespaces are owned by
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the user namespace in which they were created. A consequence of this is that
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capability checks for access to a given network namespace are done by checking
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whether a task has the given capability in the context of the user namespace
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that owns the network namespace -- not necessarily the user namespace under
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which the given task runs. Therefore spawning a process in a new user namespace
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effectively prevents it from accessing the network namespace owned by the
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initial namespace. This is a deal-breaker for any application that expects to
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retain the CAP_NET_ADMIN capability for the purpose of adjusting network
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configurations. Using user namespaces in isolation causes problems regarding
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other system interactions, including use of pid namespaces and device creation.
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Use an existing LSM
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-------------------
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None of the other in-tree LSMs have the capability to gate setid transitions, or
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even employ the security_task_fix_setuid hook at all. SELinux says of that hook:
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"Since setuid only affects the current process, and since the SELinux controls
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are not based on the Linux identity attributes, SELinux does not need to control
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this operation."
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Directions for use
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==================
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This LSM hooks the setid syscalls to make sure transitions are allowed if an
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applicable restriction policy is in place. Policies are configured through
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securityfs by writing to the safesetid/add_whitelist_policy and
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safesetid/flush_whitelist_policies files at the location where securityfs is
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mounted. The format for adding a policy is '<UID>:<UID>', using literal
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numbers, such as '123:456'. To flush the policies, any write to the file is
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sufficient. Again, configuring a policy for a UID will prevent that UID from
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obtaining auxiliary setid privileges, such as allowing a user to set up user
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namespace UID mappings.
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@ -46,3 +46,4 @@ subdirectories.
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Smack
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tomoyo
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Yama
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SafeSetID
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@ -236,12 +236,13 @@ source "security/tomoyo/Kconfig"
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source "security/apparmor/Kconfig"
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source "security/loadpin/Kconfig"
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source "security/yama/Kconfig"
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source "security/safesetid/Kconfig"
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source "security/integrity/Kconfig"
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config LSM
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string "Ordered list of enabled LSMs"
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default "yama,loadpin,integrity,selinux,smack,tomoyo,apparmor"
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default "yama,loadpin,safesetid,integrity,selinux,smack,tomoyo,apparmor"
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help
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A comma-separated list of LSMs, in initialization order.
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Any LSMs left off this list will be ignored. This can be
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@ -10,6 +10,7 @@ subdir-$(CONFIG_SECURITY_TOMOYO) += tomoyo
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subdir-$(CONFIG_SECURITY_APPARMOR) += apparmor
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subdir-$(CONFIG_SECURITY_YAMA) += yama
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subdir-$(CONFIG_SECURITY_LOADPIN) += loadpin
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subdir-$(CONFIG_SECURITY_SAFESETID) += safesetid
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# always enable default capabilities
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obj-y += commoncap.o
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@ -25,6 +26,7 @@ obj-$(CONFIG_SECURITY_TOMOYO) += tomoyo/
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obj-$(CONFIG_SECURITY_APPARMOR) += apparmor/
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obj-$(CONFIG_SECURITY_YAMA) += yama/
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obj-$(CONFIG_SECURITY_LOADPIN) += loadpin/
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obj-$(CONFIG_SECURITY_SAFESETID) += safesetid/
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obj-$(CONFIG_CGROUP_DEVICE) += device_cgroup.o
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# Object integrity file lists
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@ -0,0 +1,12 @@
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config SECURITY_SAFESETID
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bool "Gate setid transitions to limit CAP_SET{U/G}ID capabilities"
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default n
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help
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SafeSetID is an LSM module that gates the setid family of syscalls to
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restrict UID/GID transitions from a given UID/GID to only those
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approved by a system-wide whitelist. These restrictions also prohibit
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the given UIDs/GIDs from obtaining auxiliary privileges associated
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with CAP_SET{U/G}ID, such as allowing a user to set up user namespace
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UID mappings.
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If you are unsure how to answer this question, answer N.
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@ -0,0 +1,7 @@
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# SPDX-License-Identifier: GPL-2.0
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#
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# Makefile for the safesetid LSM.
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#
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obj-$(CONFIG_SECURITY_SAFESETID) := safesetid.o
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safesetid-y := lsm.o securityfs.o
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@ -0,0 +1,277 @@
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// SPDX-License-Identifier: GPL-2.0
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/*
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* SafeSetID Linux Security Module
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*
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* Author: Micah Morton <mortonm@chromium.org>
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*
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* Copyright (C) 2018 The Chromium OS Authors.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2, as
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* published by the Free Software Foundation.
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*
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*/
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#define pr_fmt(fmt) "SafeSetID: " fmt
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#include <asm/syscall.h>
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#include <linux/hashtable.h>
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#include <linux/lsm_hooks.h>
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#include <linux/module.h>
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#include <linux/ptrace.h>
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#include <linux/sched/task_stack.h>
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#include <linux/security.h>
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/* Flag indicating whether initialization completed */
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int safesetid_initialized;
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#define NUM_BITS 8 /* 128 buckets in hash table */
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static DEFINE_HASHTABLE(safesetid_whitelist_hashtable, NUM_BITS);
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/*
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* Hash table entry to store safesetid policy signifying that 'parent' user
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* can setid to 'child' user.
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*/
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struct entry {
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struct hlist_node next;
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struct hlist_node dlist; /* for deletion cleanup */
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uint64_t parent_kuid;
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uint64_t child_kuid;
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};
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static DEFINE_SPINLOCK(safesetid_whitelist_hashtable_spinlock);
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static bool check_setuid_policy_hashtable_key(kuid_t parent)
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{
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struct entry *entry;
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rcu_read_lock();
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hash_for_each_possible_rcu(safesetid_whitelist_hashtable,
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entry, next, __kuid_val(parent)) {
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if (entry->parent_kuid == __kuid_val(parent)) {
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rcu_read_unlock();
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return true;
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}
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}
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rcu_read_unlock();
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return false;
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}
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static bool check_setuid_policy_hashtable_key_value(kuid_t parent,
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kuid_t child)
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{
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struct entry *entry;
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rcu_read_lock();
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hash_for_each_possible_rcu(safesetid_whitelist_hashtable,
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entry, next, __kuid_val(parent)) {
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if (entry->parent_kuid == __kuid_val(parent) &&
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entry->child_kuid == __kuid_val(child)) {
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rcu_read_unlock();
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return true;
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}
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}
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rcu_read_unlock();
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return false;
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}
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static int safesetid_security_capable(const struct cred *cred,
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struct user_namespace *ns,
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int cap,
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unsigned int opts)
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{
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if (cap == CAP_SETUID &&
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check_setuid_policy_hashtable_key(cred->uid)) {
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if (!(opts & CAP_OPT_INSETID)) {
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/*
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* Deny if we're not in a set*uid() syscall to avoid
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* giving powers gated by CAP_SETUID that are related
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* to functionality other than calling set*uid() (e.g.
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* allowing user to set up userns uid mappings).
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*/
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pr_warn("Operation requires CAP_SETUID, which is not available to UID %u for operations besides approved set*uid transitions",
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__kuid_val(cred->uid));
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return -1;
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}
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}
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return 0;
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}
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static int check_uid_transition(kuid_t parent, kuid_t child)
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{
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if (check_setuid_policy_hashtable_key_value(parent, child))
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return 0;
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pr_warn("UID transition (%d -> %d) blocked",
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__kuid_val(parent),
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__kuid_val(child));
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/*
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* Kill this process to avoid potential security vulnerabilities
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* that could arise from a missing whitelist entry preventing a
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* privileged process from dropping to a lesser-privileged one.
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*/
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force_sig(SIGKILL, current);
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return -EACCES;
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}
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/*
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* Check whether there is either an exception for user under old cred struct to
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* set*uid to user under new cred struct, or the UID transition is allowed (by
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* Linux set*uid rules) even without CAP_SETUID.
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*/
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static int safesetid_task_fix_setuid(struct cred *new,
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const struct cred *old,
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int flags)
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{
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/* Do nothing if there are no setuid restrictions for this UID. */
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if (!check_setuid_policy_hashtable_key(old->uid))
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return 0;
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switch (flags) {
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case LSM_SETID_RE:
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/*
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* Users for which setuid restrictions exist can only set the
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* real UID to the real UID or the effective UID, unless an
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* explicit whitelist policy allows the transition.
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*/
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if (!uid_eq(old->uid, new->uid) &&
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!uid_eq(old->euid, new->uid)) {
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return check_uid_transition(old->uid, new->uid);
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}
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/*
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* Users for which setuid restrictions exist can only set the
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* effective UID to the real UID, the effective UID, or the
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* saved set-UID, unless an explicit whitelist policy allows
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* the transition.
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*/
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if (!uid_eq(old->uid, new->euid) &&
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!uid_eq(old->euid, new->euid) &&
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!uid_eq(old->suid, new->euid)) {
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return check_uid_transition(old->euid, new->euid);
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}
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break;
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case LSM_SETID_ID:
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/*
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* Users for which setuid restrictions exist cannot change the
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* real UID or saved set-UID unless an explicit whitelist
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* policy allows the transition.
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*/
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if (!uid_eq(old->uid, new->uid))
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return check_uid_transition(old->uid, new->uid);
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if (!uid_eq(old->suid, new->suid))
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return check_uid_transition(old->suid, new->suid);
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break;
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case LSM_SETID_RES:
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/*
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* Users for which setuid restrictions exist cannot change the
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* real UID, effective UID, or saved set-UID to anything but
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* one of: the current real UID, the current effective UID or
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* the current saved set-user-ID unless an explicit whitelist
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* policy allows the transition.
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*/
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if (!uid_eq(new->uid, old->uid) &&
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!uid_eq(new->uid, old->euid) &&
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!uid_eq(new->uid, old->suid)) {
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return check_uid_transition(old->uid, new->uid);
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}
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if (!uid_eq(new->euid, old->uid) &&
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!uid_eq(new->euid, old->euid) &&
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!uid_eq(new->euid, old->suid)) {
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return check_uid_transition(old->euid, new->euid);
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}
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if (!uid_eq(new->suid, old->uid) &&
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!uid_eq(new->suid, old->euid) &&
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!uid_eq(new->suid, old->suid)) {
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return check_uid_transition(old->suid, new->suid);
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}
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break;
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case LSM_SETID_FS:
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/*
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* Users for which setuid restrictions exist cannot change the
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* filesystem UID to anything but one of: the current real UID,
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* the current effective UID or the current saved set-UID
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* unless an explicit whitelist policy allows the transition.
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*/
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if (!uid_eq(new->fsuid, old->uid) &&
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!uid_eq(new->fsuid, old->euid) &&
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!uid_eq(new->fsuid, old->suid) &&
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!uid_eq(new->fsuid, old->fsuid)) {
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return check_uid_transition(old->fsuid, new->fsuid);
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}
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break;
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default:
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pr_warn("Unknown setid state %d\n", flags);
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force_sig(SIGKILL, current);
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return -EINVAL;
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}
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return 0;
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}
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int add_safesetid_whitelist_entry(kuid_t parent, kuid_t child)
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{
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struct entry *new;
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/* Return if entry already exists */
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if (check_setuid_policy_hashtable_key_value(parent, child))
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return 0;
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new = kzalloc(sizeof(struct entry), GFP_KERNEL);
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if (!new)
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return -ENOMEM;
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new->parent_kuid = __kuid_val(parent);
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new->child_kuid = __kuid_val(child);
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spin_lock(&safesetid_whitelist_hashtable_spinlock);
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hash_add_rcu(safesetid_whitelist_hashtable,
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&new->next,
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__kuid_val(parent));
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spin_unlock(&safesetid_whitelist_hashtable_spinlock);
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return 0;
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}
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void flush_safesetid_whitelist_entries(void)
|
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{
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struct entry *entry;
|
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struct hlist_node *hlist_node;
|
||||
unsigned int bkt_loop_cursor;
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HLIST_HEAD(free_list);
|
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/*
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* Could probably use hash_for_each_rcu here instead, but this should
|
||||
* be fine as well.
|
||||
*/
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spin_lock(&safesetid_whitelist_hashtable_spinlock);
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hash_for_each_safe(safesetid_whitelist_hashtable, bkt_loop_cursor,
|
||||
hlist_node, entry, next) {
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hash_del_rcu(&entry->next);
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hlist_add_head(&entry->dlist, &free_list);
|
||||
}
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||||
spin_unlock(&safesetid_whitelist_hashtable_spinlock);
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synchronize_rcu();
|
||||
hlist_for_each_entry_safe(entry, hlist_node, &free_list, dlist) {
|
||||
hlist_del(&entry->dlist);
|
||||
kfree(entry);
|
||||
}
|
||||
}
|
||||
|
||||
static struct security_hook_list safesetid_security_hooks[] = {
|
||||
LSM_HOOK_INIT(task_fix_setuid, safesetid_task_fix_setuid),
|
||||
LSM_HOOK_INIT(capable, safesetid_security_capable)
|
||||
};
|
||||
|
||||
static int __init safesetid_security_init(void)
|
||||
{
|
||||
security_add_hooks(safesetid_security_hooks,
|
||||
ARRAY_SIZE(safesetid_security_hooks), "safesetid");
|
||||
|
||||
/* Report that SafeSetID successfully initialized */
|
||||
safesetid_initialized = 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
DEFINE_LSM(safesetid_security_init) = {
|
||||
.init = safesetid_security_init,
|
||||
};
|
||||
|
|
@ -0,0 +1,33 @@
|
|||
/* SPDX-License-Identifier: GPL-2.0 */
|
||||
/*
|
||||
* SafeSetID Linux Security Module
|
||||
*
|
||||
* Author: Micah Morton <mortonm@chromium.org>
|
||||
*
|
||||
* Copyright (C) 2018 The Chromium OS Authors.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2, as
|
||||
* published by the Free Software Foundation.
|
||||
*
|
||||
*/
|
||||
#ifndef _SAFESETID_H
|
||||
#define _SAFESETID_H
|
||||
|
||||
#include <linux/types.h>
|
||||
|
||||
/* Flag indicating whether initialization completed */
|
||||
extern int safesetid_initialized;
|
||||
|
||||
/* Function type. */
|
||||
enum safesetid_whitelist_file_write_type {
|
||||
SAFESETID_WHITELIST_ADD, /* Add whitelist policy. */
|
||||
SAFESETID_WHITELIST_FLUSH, /* Flush whitelist policies. */
|
||||
};
|
||||
|
||||
/* Add entry to safesetid whitelist to allow 'parent' to setid to 'child'. */
|
||||
int add_safesetid_whitelist_entry(kuid_t parent, kuid_t child);
|
||||
|
||||
void flush_safesetid_whitelist_entries(void);
|
||||
|
||||
#endif /* _SAFESETID_H */
|
||||
|
|
@ -0,0 +1,193 @@
|
|||
// SPDX-License-Identifier: GPL-2.0
|
||||
/*
|
||||
* SafeSetID Linux Security Module
|
||||
*
|
||||
* Author: Micah Morton <mortonm@chromium.org>
|
||||
*
|
||||
* Copyright (C) 2018 The Chromium OS Authors.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License version 2, as
|
||||
* published by the Free Software Foundation.
|
||||
*
|
||||
*/
|
||||
#include <linux/security.h>
|
||||
#include <linux/cred.h>
|
||||
|
||||
#include "lsm.h"
|
||||
|
||||
static struct dentry *safesetid_policy_dir;
|
||||
|
||||
struct safesetid_file_entry {
|
||||
const char *name;
|
||||
enum safesetid_whitelist_file_write_type type;
|
||||
struct dentry *dentry;
|
||||
};
|
||||
|
||||
static struct safesetid_file_entry safesetid_files[] = {
|
||||
{.name = "add_whitelist_policy",
|
||||
.type = SAFESETID_WHITELIST_ADD},
|
||||
{.name = "flush_whitelist_policies",
|
||||
.type = SAFESETID_WHITELIST_FLUSH},
|
||||
};
|
||||
|
||||
/*
|
||||
* In the case the input buffer contains one or more invalid UIDs, the kuid_t
|
||||
* variables pointed to by 'parent' and 'child' will get updated but this
|
||||
* function will return an error.
|
||||
*/
|
||||
static int parse_safesetid_whitelist_policy(const char __user *buf,
|
||||
size_t len,
|
||||
kuid_t *parent,
|
||||
kuid_t *child)
|
||||
{
|
||||
char *kern_buf;
|
||||
char *parent_buf;
|
||||
char *child_buf;
|
||||
const char separator[] = ":";
|
||||
int ret;
|
||||
size_t first_substring_length;
|
||||
long parsed_parent;
|
||||
long parsed_child;
|
||||
|
||||
/* Duplicate string from user memory and NULL-terminate */
|
||||
kern_buf = memdup_user_nul(buf, len);
|
||||
if (IS_ERR(kern_buf))
|
||||
return PTR_ERR(kern_buf);
|
||||
|
||||
/*
|
||||
* Format of |buf| string should be <UID>:<UID>.
|
||||
* Find location of ":" in kern_buf (copied from |buf|).
|
||||
*/
|
||||
first_substring_length = strcspn(kern_buf, separator);
|
||||
if (first_substring_length == 0 || first_substring_length == len) {
|
||||
ret = -EINVAL;
|
||||
goto free_kern;
|
||||
}
|
||||
|
||||
parent_buf = kmemdup_nul(kern_buf, first_substring_length, GFP_KERNEL);
|
||||
if (!parent_buf) {
|
||||
ret = -ENOMEM;
|
||||
goto free_kern;
|
||||
}
|
||||
|
||||
ret = kstrtol(parent_buf, 0, &parsed_parent);
|
||||
if (ret)
|
||||
goto free_both;
|
||||
|
||||
child_buf = kern_buf + first_substring_length + 1;
|
||||
ret = kstrtol(child_buf, 0, &parsed_child);
|
||||
if (ret)
|
||||
goto free_both;
|
||||
|
||||
*parent = make_kuid(current_user_ns(), parsed_parent);
|
||||
if (!uid_valid(*parent)) {
|
||||
ret = -EINVAL;
|
||||
goto free_both;
|
||||
}
|
||||
|
||||
*child = make_kuid(current_user_ns(), parsed_child);
|
||||
if (!uid_valid(*child)) {
|
||||
ret = -EINVAL;
|
||||
goto free_both;
|
||||
}
|
||||
|
||||
free_both:
|
||||
kfree(parent_buf);
|
||||
free_kern:
|
||||
kfree(kern_buf);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static ssize_t safesetid_file_write(struct file *file,
|
||||
const char __user *buf,
|
||||
size_t len,
|
||||
loff_t *ppos)
|
||||
{
|
||||
struct safesetid_file_entry *file_entry =
|
||||
file->f_inode->i_private;
|
||||
kuid_t parent;
|
||||
kuid_t child;
|
||||
int ret;
|
||||
|
||||
if (!ns_capable(current_user_ns(), CAP_MAC_ADMIN))
|
||||
return -EPERM;
|
||||
|
||||
if (*ppos != 0)
|
||||
return -EINVAL;
|
||||
|
||||
switch (file_entry->type) {
|
||||
case SAFESETID_WHITELIST_FLUSH:
|
||||
flush_safesetid_whitelist_entries();
|
||||
break;
|
||||
case SAFESETID_WHITELIST_ADD:
|
||||
ret = parse_safesetid_whitelist_policy(buf, len, &parent,
|
||||
&child);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = add_safesetid_whitelist_entry(parent, child);
|
||||
if (ret)
|
||||
return ret;
|
||||
break;
|
||||
default:
|
||||
pr_warn("Unknown securityfs file %d\n", file_entry->type);
|
||||
break;
|
||||
}
|
||||
|
||||
/* Return len on success so caller won't keep trying to write */
|
||||
return len;
|
||||
}
|
||||
|
||||
static const struct file_operations safesetid_file_fops = {
|
||||
.write = safesetid_file_write,
|
||||
};
|
||||
|
||||
static void safesetid_shutdown_securityfs(void)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < ARRAY_SIZE(safesetid_files); ++i) {
|
||||
struct safesetid_file_entry *entry =
|
||||
&safesetid_files[i];
|
||||
securityfs_remove(entry->dentry);
|
||||
entry->dentry = NULL;
|
||||
}
|
||||
|
||||
securityfs_remove(safesetid_policy_dir);
|
||||
safesetid_policy_dir = NULL;
|
||||
}
|
||||
|
||||
static int __init safesetid_init_securityfs(void)
|
||||
{
|
||||
int i;
|
||||
int ret;
|
||||
|
||||
if (!safesetid_initialized)
|
||||
return 0;
|
||||
|
||||
safesetid_policy_dir = securityfs_create_dir("safesetid", NULL);
|
||||
if (!safesetid_policy_dir) {
|
||||
ret = PTR_ERR(safesetid_policy_dir);
|
||||
goto error;
|
||||
}
|
||||
|
||||
for (i = 0; i < ARRAY_SIZE(safesetid_files); ++i) {
|
||||
struct safesetid_file_entry *entry =
|
||||
&safesetid_files[i];
|
||||
entry->dentry = securityfs_create_file(
|
||||
entry->name, 0200, safesetid_policy_dir,
|
||||
entry, &safesetid_file_fops);
|
||||
if (IS_ERR(entry->dentry)) {
|
||||
ret = PTR_ERR(entry->dentry);
|
||||
goto error;
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
error:
|
||||
safesetid_shutdown_securityfs();
|
||||
return ret;
|
||||
}
|
||||
fs_initcall(safesetid_init_securityfs);
|
||||
Загрузка…
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