7342 lines
184 KiB
C
7342 lines
184 KiB
C
/*
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* NSA Security-Enhanced Linux (SELinux) security module
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*
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* This file contains the SELinux hook function implementations.
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*
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* Authors: Stephen Smalley, <sds@tycho.nsa.gov>
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* Chris Vance, <cvance@nai.com>
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* Wayne Salamon, <wsalamon@nai.com>
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* James Morris <jmorris@redhat.com>
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*
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* Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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* Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
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* Eric Paris <eparis@redhat.com>
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* Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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* <dgoeddel@trustedcs.com>
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* Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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* Paul Moore <paul@paul-moore.com>
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* Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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* Yuichi Nakamura <ynakam@hitachisoft.jp>
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* Copyright (C) 2016 Mellanox Technologies
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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,
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* as published by the Free Software Foundation.
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*/
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#include <linux/init.h>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
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#include <linux/sched/signal.h>
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#include <linux/sched/task.h>
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#include <linux/lsm_hooks.h>
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#include <linux/xattr.h>
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#include <linux/capability.h>
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#include <linux/unistd.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/slab.h>
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#include <linux/pagemap.h>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
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#include <linux/spinlock.h>
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#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
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#include <linux/mount.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/netfilter_ipv6.h>
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#include <linux/tty.h>
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#include <net/icmp.h>
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#include <net/ip.h> /* for local_port_range[] */
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#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
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#include <net/inet_connection_sock.h>
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#include <net/net_namespace.h>
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#include <net/netlabel.h>
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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#include <linux/atomic.h>
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#include <linux/bitops.h>
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#include <linux/interrupt.h>
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#include <linux/netdevice.h> /* for network interface checks */
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#include <net/netlink.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/sctp.h>
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#include <net/sctp/structs.h>
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#include <linux/quota.h>
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#include <linux/un.h> /* for Unix socket types */
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#include <net/af_unix.h> /* for Unix socket types */
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#include <linux/parser.h>
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#include <linux/nfs_mount.h>
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#include <net/ipv6.h>
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#include <linux/hugetlb.h>
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#include <linux/personality.h>
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#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include <linux/export.h>
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#include <linux/msg.h>
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#include <linux/shm.h>
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#include <linux/bpf.h>
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#include "avc.h"
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#include "objsec.h"
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#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "ibpkey.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#include "avc_ss.h"
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struct selinux_state selinux_state;
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/* SECMARK reference count */
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static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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static int selinux_enforcing_boot;
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static int __init enforcing_setup(char *str)
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{
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unsigned long enforcing;
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if (!kstrtoul(str, 0, &enforcing))
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selinux_enforcing_boot = enforcing ? 1 : 0;
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return 1;
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}
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__setup("enforcing=", enforcing_setup);
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#else
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#define selinux_enforcing_boot 1
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#endif
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#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
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int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
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static int __init selinux_enabled_setup(char *str)
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{
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unsigned long enabled;
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if (!kstrtoul(str, 0, &enabled))
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selinux_enabled = enabled ? 1 : 0;
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return 1;
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}
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__setup("selinux=", selinux_enabled_setup);
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#else
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int selinux_enabled = 1;
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#endif
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static unsigned int selinux_checkreqprot_boot =
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CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
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static int __init checkreqprot_setup(char *str)
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{
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unsigned long checkreqprot;
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if (!kstrtoul(str, 0, &checkreqprot))
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selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
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return 1;
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}
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__setup("checkreqprot=", checkreqprot_setup);
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static struct kmem_cache *sel_inode_cache;
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static struct kmem_cache *file_security_cache;
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/**
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* selinux_secmark_enabled - Check to see if SECMARK is currently enabled
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*
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* Description:
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* This function checks the SECMARK reference counter to see if any SECMARK
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* targets are currently configured, if the reference counter is greater than
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* zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
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* enabled, false (0) if SECMARK is disabled. If the always_check_network
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* policy capability is enabled, SECMARK is always considered enabled.
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*
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*/
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static int selinux_secmark_enabled(void)
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{
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return (selinux_policycap_alwaysnetwork() ||
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atomic_read(&selinux_secmark_refcount));
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}
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/**
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* selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
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*
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* Description:
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* This function checks if NetLabel or labeled IPSEC is enabled. Returns true
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* (1) if any are enabled or false (0) if neither are enabled. If the
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* always_check_network policy capability is enabled, peer labeling
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* is always considered enabled.
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*
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*/
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static int selinux_peerlbl_enabled(void)
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{
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return (selinux_policycap_alwaysnetwork() ||
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netlbl_enabled() || selinux_xfrm_enabled());
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}
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static int selinux_netcache_avc_callback(u32 event)
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{
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if (event == AVC_CALLBACK_RESET) {
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sel_netif_flush();
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sel_netnode_flush();
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sel_netport_flush();
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synchronize_net();
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}
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return 0;
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}
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static int selinux_lsm_notifier_avc_callback(u32 event)
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{
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if (event == AVC_CALLBACK_RESET) {
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sel_ib_pkey_flush();
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call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
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}
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return 0;
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}
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/*
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* initialise the security for the init task
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*/
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static void cred_init_security(void)
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{
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struct cred *cred = (struct cred *) current->real_cred;
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struct task_security_struct *tsec;
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tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
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if (!tsec)
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panic("SELinux: Failed to initialize initial task.\n");
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tsec->osid = tsec->sid = SECINITSID_KERNEL;
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cred->security = tsec;
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}
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/*
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* get the security ID of a set of credentials
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*/
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static inline u32 cred_sid(const struct cred *cred)
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{
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const struct task_security_struct *tsec;
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tsec = cred->security;
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return tsec->sid;
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}
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/*
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* get the objective security ID of a task
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*/
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static inline u32 task_sid(const struct task_struct *task)
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{
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u32 sid;
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rcu_read_lock();
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sid = cred_sid(__task_cred(task));
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rcu_read_unlock();
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return sid;
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}
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/* Allocate and free functions for each kind of security blob. */
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static int inode_alloc_security(struct inode *inode)
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{
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struct inode_security_struct *isec;
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u32 sid = current_sid();
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isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
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if (!isec)
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return -ENOMEM;
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spin_lock_init(&isec->lock);
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INIT_LIST_HEAD(&isec->list);
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isec->inode = inode;
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isec->sid = SECINITSID_UNLABELED;
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isec->sclass = SECCLASS_FILE;
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isec->task_sid = sid;
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isec->initialized = LABEL_INVALID;
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inode->i_security = isec;
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return 0;
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}
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static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
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/*
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* Try reloading inode security labels that have been marked as invalid. The
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* @may_sleep parameter indicates when sleeping and thus reloading labels is
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* allowed; when set to false, returns -ECHILD when the label is
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* invalid. The @dentry parameter should be set to a dentry of the inode.
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*/
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static int __inode_security_revalidate(struct inode *inode,
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struct dentry *dentry,
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bool may_sleep)
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{
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struct inode_security_struct *isec = inode->i_security;
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might_sleep_if(may_sleep);
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if (selinux_state.initialized &&
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isec->initialized != LABEL_INITIALIZED) {
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if (!may_sleep)
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return -ECHILD;
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/*
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* Try reloading the inode security label. This will fail if
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* @opt_dentry is NULL and no dentry for this inode can be
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* found; in that case, continue using the old label.
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*/
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inode_doinit_with_dentry(inode, dentry);
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}
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return 0;
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}
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static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
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{
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return inode->i_security;
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}
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static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
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{
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int error;
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error = __inode_security_revalidate(inode, NULL, !rcu);
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if (error)
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return ERR_PTR(error);
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return inode->i_security;
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}
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/*
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* Get the security label of an inode.
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*/
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static struct inode_security_struct *inode_security(struct inode *inode)
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{
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__inode_security_revalidate(inode, NULL, true);
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return inode->i_security;
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}
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static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
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{
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struct inode *inode = d_backing_inode(dentry);
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return inode->i_security;
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}
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/*
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* Get the security label of a dentry's backing inode.
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*/
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static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
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{
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struct inode *inode = d_backing_inode(dentry);
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__inode_security_revalidate(inode, dentry, true);
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return inode->i_security;
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}
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static void inode_free_rcu(struct rcu_head *head)
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{
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struct inode_security_struct *isec;
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isec = container_of(head, struct inode_security_struct, rcu);
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kmem_cache_free(sel_inode_cache, isec);
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}
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static void inode_free_security(struct inode *inode)
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{
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struct inode_security_struct *isec = inode->i_security;
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struct superblock_security_struct *sbsec = inode->i_sb->s_security;
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/*
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* As not all inode security structures are in a list, we check for
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* empty list outside of the lock to make sure that we won't waste
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* time taking a lock doing nothing.
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*
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* The list_del_init() function can be safely called more than once.
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* It should not be possible for this function to be called with
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* concurrent list_add(), but for better safety against future changes
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* in the code, we use list_empty_careful() here.
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*/
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if (!list_empty_careful(&isec->list)) {
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spin_lock(&sbsec->isec_lock);
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list_del_init(&isec->list);
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spin_unlock(&sbsec->isec_lock);
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}
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/*
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* The inode may still be referenced in a path walk and
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* a call to selinux_inode_permission() can be made
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* after inode_free_security() is called. Ideally, the VFS
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* wouldn't do this, but fixing that is a much harder
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* job. For now, simply free the i_security via RCU, and
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* leave the current inode->i_security pointer intact.
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* The inode will be freed after the RCU grace period too.
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*/
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call_rcu(&isec->rcu, inode_free_rcu);
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}
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static int file_alloc_security(struct file *file)
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{
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struct file_security_struct *fsec;
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u32 sid = current_sid();
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fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
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if (!fsec)
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return -ENOMEM;
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fsec->sid = sid;
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fsec->fown_sid = sid;
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file->f_security = fsec;
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return 0;
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}
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static void file_free_security(struct file *file)
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{
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struct file_security_struct *fsec = file->f_security;
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file->f_security = NULL;
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kmem_cache_free(file_security_cache, fsec);
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}
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static int superblock_alloc_security(struct super_block *sb)
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{
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struct superblock_security_struct *sbsec;
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sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
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if (!sbsec)
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return -ENOMEM;
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mutex_init(&sbsec->lock);
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INIT_LIST_HEAD(&sbsec->isec_head);
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spin_lock_init(&sbsec->isec_lock);
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sbsec->sb = sb;
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sbsec->sid = SECINITSID_UNLABELED;
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sbsec->def_sid = SECINITSID_FILE;
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sbsec->mntpoint_sid = SECINITSID_UNLABELED;
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sb->s_security = sbsec;
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return 0;
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}
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static void superblock_free_security(struct super_block *sb)
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{
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struct superblock_security_struct *sbsec = sb->s_security;
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sb->s_security = NULL;
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kfree(sbsec);
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}
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static inline int inode_doinit(struct inode *inode)
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{
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return inode_doinit_with_dentry(inode, NULL);
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}
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enum {
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Opt_error = -1,
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Opt_context = 1,
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Opt_fscontext = 2,
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Opt_defcontext = 3,
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Opt_rootcontext = 4,
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Opt_labelsupport = 5,
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Opt_nextmntopt = 6,
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};
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#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
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|
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static const match_table_t tokens = {
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{Opt_context, CONTEXT_STR "%s"},
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{Opt_fscontext, FSCONTEXT_STR "%s"},
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{Opt_defcontext, DEFCONTEXT_STR "%s"},
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{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
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{Opt_labelsupport, LABELSUPP_STR},
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{Opt_error, NULL},
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};
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|
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#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
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|
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static int may_context_mount_sb_relabel(u32 sid,
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struct superblock_security_struct *sbsec,
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const struct cred *cred)
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{
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const struct task_security_struct *tsec = cred->security;
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int rc;
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rc = avc_has_perm(&selinux_state,
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tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
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FILESYSTEM__RELABELFROM, NULL);
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if (rc)
|
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return rc;
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rc = avc_has_perm(&selinux_state,
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tsec->sid, sid, SECCLASS_FILESYSTEM,
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FILESYSTEM__RELABELTO, NULL);
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return rc;
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}
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|
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static int may_context_mount_inode_relabel(u32 sid,
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struct superblock_security_struct *sbsec,
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const struct cred *cred)
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{
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const struct task_security_struct *tsec = cred->security;
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int rc;
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rc = avc_has_perm(&selinux_state,
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tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
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FILESYSTEM__RELABELFROM, NULL);
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if (rc)
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return rc;
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rc = avc_has_perm(&selinux_state,
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sid, sbsec->sid, SECCLASS_FILESYSTEM,
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FILESYSTEM__ASSOCIATE, NULL);
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return rc;
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}
|
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|
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static int selinux_is_sblabel_mnt(struct super_block *sb)
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{
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struct superblock_security_struct *sbsec = sb->s_security;
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return sbsec->behavior == SECURITY_FS_USE_XATTR ||
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sbsec->behavior == SECURITY_FS_USE_TRANS ||
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sbsec->behavior == SECURITY_FS_USE_TASK ||
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sbsec->behavior == SECURITY_FS_USE_NATIVE ||
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/* Special handling. Genfs but also in-core setxattr handler */
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!strcmp(sb->s_type->name, "sysfs") ||
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!strcmp(sb->s_type->name, "pstore") ||
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!strcmp(sb->s_type->name, "debugfs") ||
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|
!strcmp(sb->s_type->name, "tracefs") ||
|
|
!strcmp(sb->s_type->name, "rootfs") ||
|
|
(selinux_policycap_cgroupseclabel() &&
|
|
(!strcmp(sb->s_type->name, "cgroup") ||
|
|
!strcmp(sb->s_type->name, "cgroup2")));
|
|
}
|
|
|
|
static int sb_finish_set_opts(struct super_block *sb)
|
|
{
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
struct dentry *root = sb->s_root;
|
|
struct inode *root_inode = d_backing_inode(root);
|
|
int rc = 0;
|
|
|
|
if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
|
|
/* Make sure that the xattr handler exists and that no
|
|
error other than -ENODATA is returned by getxattr on
|
|
the root directory. -ENODATA is ok, as this may be
|
|
the first boot of the SELinux kernel before we have
|
|
assigned xattr values to the filesystem. */
|
|
if (!(root_inode->i_opflags & IOP_XATTR)) {
|
|
pr_warn("SELinux: (dev %s, type %s) has no "
|
|
"xattr support\n", sb->s_id, sb->s_type->name);
|
|
rc = -EOPNOTSUPP;
|
|
goto out;
|
|
}
|
|
|
|
rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
|
|
if (rc < 0 && rc != -ENODATA) {
|
|
if (rc == -EOPNOTSUPP)
|
|
pr_warn("SELinux: (dev %s, type "
|
|
"%s) has no security xattr handler\n",
|
|
sb->s_id, sb->s_type->name);
|
|
else
|
|
pr_warn("SELinux: (dev %s, type "
|
|
"%s) getxattr errno %d\n", sb->s_id,
|
|
sb->s_type->name, -rc);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
sbsec->flags |= SE_SBINITIALIZED;
|
|
|
|
/*
|
|
* Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
|
|
* leave the flag untouched because sb_clone_mnt_opts might be handing
|
|
* us a superblock that needs the flag to be cleared.
|
|
*/
|
|
if (selinux_is_sblabel_mnt(sb))
|
|
sbsec->flags |= SBLABEL_MNT;
|
|
else
|
|
sbsec->flags &= ~SBLABEL_MNT;
|
|
|
|
/* Initialize the root inode. */
|
|
rc = inode_doinit_with_dentry(root_inode, root);
|
|
|
|
/* Initialize any other inodes associated with the superblock, e.g.
|
|
inodes created prior to initial policy load or inodes created
|
|
during get_sb by a pseudo filesystem that directly
|
|
populates itself. */
|
|
spin_lock(&sbsec->isec_lock);
|
|
next_inode:
|
|
if (!list_empty(&sbsec->isec_head)) {
|
|
struct inode_security_struct *isec =
|
|
list_entry(sbsec->isec_head.next,
|
|
struct inode_security_struct, list);
|
|
struct inode *inode = isec->inode;
|
|
list_del_init(&isec->list);
|
|
spin_unlock(&sbsec->isec_lock);
|
|
inode = igrab(inode);
|
|
if (inode) {
|
|
if (!IS_PRIVATE(inode))
|
|
inode_doinit(inode);
|
|
iput(inode);
|
|
}
|
|
spin_lock(&sbsec->isec_lock);
|
|
goto next_inode;
|
|
}
|
|
spin_unlock(&sbsec->isec_lock);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* This function should allow an FS to ask what it's mount security
|
|
* options were so it can use those later for submounts, displaying
|
|
* mount options, or whatever.
|
|
*/
|
|
static int selinux_get_mnt_opts(const struct super_block *sb,
|
|
struct security_mnt_opts *opts)
|
|
{
|
|
int rc = 0, i;
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
char *context = NULL;
|
|
u32 len;
|
|
char tmp;
|
|
|
|
security_init_mnt_opts(opts);
|
|
|
|
if (!(sbsec->flags & SE_SBINITIALIZED))
|
|
return -EINVAL;
|
|
|
|
if (!selinux_state.initialized)
|
|
return -EINVAL;
|
|
|
|
/* make sure we always check enough bits to cover the mask */
|
|
BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
|
|
|
|
tmp = sbsec->flags & SE_MNTMASK;
|
|
/* count the number of mount options for this sb */
|
|
for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
|
|
if (tmp & 0x01)
|
|
opts->num_mnt_opts++;
|
|
tmp >>= 1;
|
|
}
|
|
/* Check if the Label support flag is set */
|
|
if (sbsec->flags & SBLABEL_MNT)
|
|
opts->num_mnt_opts++;
|
|
|
|
opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
|
|
if (!opts->mnt_opts) {
|
|
rc = -ENOMEM;
|
|
goto out_free;
|
|
}
|
|
|
|
opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
|
|
if (!opts->mnt_opts_flags) {
|
|
rc = -ENOMEM;
|
|
goto out_free;
|
|
}
|
|
|
|
i = 0;
|
|
if (sbsec->flags & FSCONTEXT_MNT) {
|
|
rc = security_sid_to_context(&selinux_state, sbsec->sid,
|
|
&context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & CONTEXT_MNT) {
|
|
rc = security_sid_to_context(&selinux_state,
|
|
sbsec->mntpoint_sid,
|
|
&context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = CONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & DEFCONTEXT_MNT) {
|
|
rc = security_sid_to_context(&selinux_state, sbsec->def_sid,
|
|
&context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & ROOTCONTEXT_MNT) {
|
|
struct dentry *root = sbsec->sb->s_root;
|
|
struct inode_security_struct *isec = backing_inode_security(root);
|
|
|
|
rc = security_sid_to_context(&selinux_state, isec->sid,
|
|
&context, &len);
|
|
if (rc)
|
|
goto out_free;
|
|
opts->mnt_opts[i] = context;
|
|
opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
|
|
}
|
|
if (sbsec->flags & SBLABEL_MNT) {
|
|
opts->mnt_opts[i] = NULL;
|
|
opts->mnt_opts_flags[i++] = SBLABEL_MNT;
|
|
}
|
|
|
|
BUG_ON(i != opts->num_mnt_opts);
|
|
|
|
return 0;
|
|
|
|
out_free:
|
|
security_free_mnt_opts(opts);
|
|
return rc;
|
|
}
|
|
|
|
static int bad_option(struct superblock_security_struct *sbsec, char flag,
|
|
u32 old_sid, u32 new_sid)
|
|
{
|
|
char mnt_flags = sbsec->flags & SE_MNTMASK;
|
|
|
|
/* check if the old mount command had the same options */
|
|
if (sbsec->flags & SE_SBINITIALIZED)
|
|
if (!(sbsec->flags & flag) ||
|
|
(old_sid != new_sid))
|
|
return 1;
|
|
|
|
/* check if we were passed the same options twice,
|
|
* aka someone passed context=a,context=b
|
|
*/
|
|
if (!(sbsec->flags & SE_SBINITIALIZED))
|
|
if (mnt_flags & flag)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Allow filesystems with binary mount data to explicitly set mount point
|
|
* labeling information.
|
|
*/
|
|
static int selinux_set_mnt_opts(struct super_block *sb,
|
|
struct security_mnt_opts *opts,
|
|
unsigned long kern_flags,
|
|
unsigned long *set_kern_flags)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int rc = 0, i;
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
const char *name = sb->s_type->name;
|
|
struct dentry *root = sbsec->sb->s_root;
|
|
struct inode_security_struct *root_isec;
|
|
u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
|
|
u32 defcontext_sid = 0;
|
|
char **mount_options = opts->mnt_opts;
|
|
int *flags = opts->mnt_opts_flags;
|
|
int num_opts = opts->num_mnt_opts;
|
|
|
|
mutex_lock(&sbsec->lock);
|
|
|
|
if (!selinux_state.initialized) {
|
|
if (!num_opts) {
|
|
/* Defer initialization until selinux_complete_init,
|
|
after the initial policy is loaded and the security
|
|
server is ready to handle calls. */
|
|
goto out;
|
|
}
|
|
rc = -EINVAL;
|
|
pr_warn("SELinux: Unable to set superblock options "
|
|
"before the security server is initialized\n");
|
|
goto out;
|
|
}
|
|
if (kern_flags && !set_kern_flags) {
|
|
/* Specifying internal flags without providing a place to
|
|
* place the results is not allowed */
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Binary mount data FS will come through this function twice. Once
|
|
* from an explicit call and once from the generic calls from the vfs.
|
|
* Since the generic VFS calls will not contain any security mount data
|
|
* we need to skip the double mount verification.
|
|
*
|
|
* This does open a hole in which we will not notice if the first
|
|
* mount using this sb set explict options and a second mount using
|
|
* this sb does not set any security options. (The first options
|
|
* will be used for both mounts)
|
|
*/
|
|
if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
|
|
&& (num_opts == 0))
|
|
goto out;
|
|
|
|
root_isec = backing_inode_security_novalidate(root);
|
|
|
|
/*
|
|
* parse the mount options, check if they are valid sids.
|
|
* also check if someone is trying to mount the same sb more
|
|
* than once with different security options.
|
|
*/
|
|
for (i = 0; i < num_opts; i++) {
|
|
u32 sid;
|
|
|
|
if (flags[i] == SBLABEL_MNT)
|
|
continue;
|
|
rc = security_context_str_to_sid(&selinux_state,
|
|
mount_options[i], &sid,
|
|
GFP_KERNEL);
|
|
if (rc) {
|
|
pr_warn("SELinux: security_context_str_to_sid"
|
|
"(%s) failed for (dev %s, type %s) errno=%d\n",
|
|
mount_options[i], sb->s_id, name, rc);
|
|
goto out;
|
|
}
|
|
switch (flags[i]) {
|
|
case FSCONTEXT_MNT:
|
|
fscontext_sid = sid;
|
|
|
|
if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
|
|
fscontext_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= FSCONTEXT_MNT;
|
|
break;
|
|
case CONTEXT_MNT:
|
|
context_sid = sid;
|
|
|
|
if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
|
|
context_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= CONTEXT_MNT;
|
|
break;
|
|
case ROOTCONTEXT_MNT:
|
|
rootcontext_sid = sid;
|
|
|
|
if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
|
|
rootcontext_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= ROOTCONTEXT_MNT;
|
|
|
|
break;
|
|
case DEFCONTEXT_MNT:
|
|
defcontext_sid = sid;
|
|
|
|
if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
|
|
defcontext_sid))
|
|
goto out_double_mount;
|
|
|
|
sbsec->flags |= DEFCONTEXT_MNT;
|
|
|
|
break;
|
|
default:
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (sbsec->flags & SE_SBINITIALIZED) {
|
|
/* previously mounted with options, but not on this attempt? */
|
|
if ((sbsec->flags & SE_MNTMASK) && !num_opts)
|
|
goto out_double_mount;
|
|
rc = 0;
|
|
goto out;
|
|
}
|
|
|
|
if (strcmp(sb->s_type->name, "proc") == 0)
|
|
sbsec->flags |= SE_SBPROC | SE_SBGENFS;
|
|
|
|
if (!strcmp(sb->s_type->name, "debugfs") ||
|
|
!strcmp(sb->s_type->name, "tracefs") ||
|
|
!strcmp(sb->s_type->name, "sysfs") ||
|
|
!strcmp(sb->s_type->name, "pstore") ||
|
|
!strcmp(sb->s_type->name, "cgroup") ||
|
|
!strcmp(sb->s_type->name, "cgroup2"))
|
|
sbsec->flags |= SE_SBGENFS;
|
|
|
|
if (!sbsec->behavior) {
|
|
/*
|
|
* Determine the labeling behavior to use for this
|
|
* filesystem type.
|
|
*/
|
|
rc = security_fs_use(&selinux_state, sb);
|
|
if (rc) {
|
|
pr_warn("%s: security_fs_use(%s) returned %d\n",
|
|
__func__, sb->s_type->name, rc);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If this is a user namespace mount and the filesystem type is not
|
|
* explicitly whitelisted, then no contexts are allowed on the command
|
|
* line and security labels must be ignored.
|
|
*/
|
|
if (sb->s_user_ns != &init_user_ns &&
|
|
strcmp(sb->s_type->name, "tmpfs") &&
|
|
strcmp(sb->s_type->name, "ramfs") &&
|
|
strcmp(sb->s_type->name, "devpts")) {
|
|
if (context_sid || fscontext_sid || rootcontext_sid ||
|
|
defcontext_sid) {
|
|
rc = -EACCES;
|
|
goto out;
|
|
}
|
|
if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
|
|
sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
|
|
rc = security_transition_sid(&selinux_state,
|
|
current_sid(),
|
|
current_sid(),
|
|
SECCLASS_FILE, NULL,
|
|
&sbsec->mntpoint_sid);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
goto out_set_opts;
|
|
}
|
|
|
|
/* sets the context of the superblock for the fs being mounted. */
|
|
if (fscontext_sid) {
|
|
rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
|
|
if (rc)
|
|
goto out;
|
|
|
|
sbsec->sid = fscontext_sid;
|
|
}
|
|
|
|
/*
|
|
* Switch to using mount point labeling behavior.
|
|
* sets the label used on all file below the mountpoint, and will set
|
|
* the superblock context if not already set.
|
|
*/
|
|
if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
|
|
sbsec->behavior = SECURITY_FS_USE_NATIVE;
|
|
*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
|
|
}
|
|
|
|
if (context_sid) {
|
|
if (!fscontext_sid) {
|
|
rc = may_context_mount_sb_relabel(context_sid, sbsec,
|
|
cred);
|
|
if (rc)
|
|
goto out;
|
|
sbsec->sid = context_sid;
|
|
} else {
|
|
rc = may_context_mount_inode_relabel(context_sid, sbsec,
|
|
cred);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
if (!rootcontext_sid)
|
|
rootcontext_sid = context_sid;
|
|
|
|
sbsec->mntpoint_sid = context_sid;
|
|
sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
|
|
}
|
|
|
|
if (rootcontext_sid) {
|
|
rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
|
|
cred);
|
|
if (rc)
|
|
goto out;
|
|
|
|
root_isec->sid = rootcontext_sid;
|
|
root_isec->initialized = LABEL_INITIALIZED;
|
|
}
|
|
|
|
if (defcontext_sid) {
|
|
if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
|
|
sbsec->behavior != SECURITY_FS_USE_NATIVE) {
|
|
rc = -EINVAL;
|
|
pr_warn("SELinux: defcontext option is "
|
|
"invalid for this filesystem type\n");
|
|
goto out;
|
|
}
|
|
|
|
if (defcontext_sid != sbsec->def_sid) {
|
|
rc = may_context_mount_inode_relabel(defcontext_sid,
|
|
sbsec, cred);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
sbsec->def_sid = defcontext_sid;
|
|
}
|
|
|
|
out_set_opts:
|
|
rc = sb_finish_set_opts(sb);
|
|
out:
|
|
mutex_unlock(&sbsec->lock);
|
|
return rc;
|
|
out_double_mount:
|
|
rc = -EINVAL;
|
|
pr_warn("SELinux: mount invalid. Same superblock, different "
|
|
"security settings for (dev %s, type %s)\n", sb->s_id, name);
|
|
goto out;
|
|
}
|
|
|
|
static int selinux_cmp_sb_context(const struct super_block *oldsb,
|
|
const struct super_block *newsb)
|
|
{
|
|
struct superblock_security_struct *old = oldsb->s_security;
|
|
struct superblock_security_struct *new = newsb->s_security;
|
|
char oldflags = old->flags & SE_MNTMASK;
|
|
char newflags = new->flags & SE_MNTMASK;
|
|
|
|
if (oldflags != newflags)
|
|
goto mismatch;
|
|
if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
|
|
goto mismatch;
|
|
if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
|
|
goto mismatch;
|
|
if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
|
|
goto mismatch;
|
|
if (oldflags & ROOTCONTEXT_MNT) {
|
|
struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
|
|
struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
|
|
if (oldroot->sid != newroot->sid)
|
|
goto mismatch;
|
|
}
|
|
return 0;
|
|
mismatch:
|
|
pr_warn("SELinux: mount invalid. Same superblock, "
|
|
"different security settings for (dev %s, "
|
|
"type %s)\n", newsb->s_id, newsb->s_type->name);
|
|
return -EBUSY;
|
|
}
|
|
|
|
static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
|
|
struct super_block *newsb,
|
|
unsigned long kern_flags,
|
|
unsigned long *set_kern_flags)
|
|
{
|
|
int rc = 0;
|
|
const struct superblock_security_struct *oldsbsec = oldsb->s_security;
|
|
struct superblock_security_struct *newsbsec = newsb->s_security;
|
|
|
|
int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
|
|
int set_context = (oldsbsec->flags & CONTEXT_MNT);
|
|
int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
|
|
|
|
/*
|
|
* if the parent was able to be mounted it clearly had no special lsm
|
|
* mount options. thus we can safely deal with this superblock later
|
|
*/
|
|
if (!selinux_state.initialized)
|
|
return 0;
|
|
|
|
/*
|
|
* Specifying internal flags without providing a place to
|
|
* place the results is not allowed.
|
|
*/
|
|
if (kern_flags && !set_kern_flags)
|
|
return -EINVAL;
|
|
|
|
/* how can we clone if the old one wasn't set up?? */
|
|
BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
|
|
|
|
/* if fs is reusing a sb, make sure that the contexts match */
|
|
if (newsbsec->flags & SE_SBINITIALIZED)
|
|
return selinux_cmp_sb_context(oldsb, newsb);
|
|
|
|
mutex_lock(&newsbsec->lock);
|
|
|
|
newsbsec->flags = oldsbsec->flags;
|
|
|
|
newsbsec->sid = oldsbsec->sid;
|
|
newsbsec->def_sid = oldsbsec->def_sid;
|
|
newsbsec->behavior = oldsbsec->behavior;
|
|
|
|
if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
|
|
!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
|
|
rc = security_fs_use(&selinux_state, newsb);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
|
|
newsbsec->behavior = SECURITY_FS_USE_NATIVE;
|
|
*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
|
|
}
|
|
|
|
if (set_context) {
|
|
u32 sid = oldsbsec->mntpoint_sid;
|
|
|
|
if (!set_fscontext)
|
|
newsbsec->sid = sid;
|
|
if (!set_rootcontext) {
|
|
struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
|
|
newisec->sid = sid;
|
|
}
|
|
newsbsec->mntpoint_sid = sid;
|
|
}
|
|
if (set_rootcontext) {
|
|
const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
|
|
struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
|
|
|
|
newisec->sid = oldisec->sid;
|
|
}
|
|
|
|
sb_finish_set_opts(newsb);
|
|
out:
|
|
mutex_unlock(&newsbsec->lock);
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_parse_opts_str(char *options,
|
|
struct security_mnt_opts *opts)
|
|
{
|
|
char *p;
|
|
char *context = NULL, *defcontext = NULL;
|
|
char *fscontext = NULL, *rootcontext = NULL;
|
|
int rc, num_mnt_opts = 0;
|
|
|
|
opts->num_mnt_opts = 0;
|
|
|
|
/* Standard string-based options. */
|
|
while ((p = strsep(&options, "|")) != NULL) {
|
|
int token;
|
|
substring_t args[MAX_OPT_ARGS];
|
|
|
|
if (!*p)
|
|
continue;
|
|
|
|
token = match_token(p, tokens, args);
|
|
|
|
switch (token) {
|
|
case Opt_context:
|
|
if (context || defcontext) {
|
|
rc = -EINVAL;
|
|
pr_warn(SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
context = match_strdup(&args[0]);
|
|
if (!context) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
|
|
case Opt_fscontext:
|
|
if (fscontext) {
|
|
rc = -EINVAL;
|
|
pr_warn(SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
fscontext = match_strdup(&args[0]);
|
|
if (!fscontext) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
|
|
case Opt_rootcontext:
|
|
if (rootcontext) {
|
|
rc = -EINVAL;
|
|
pr_warn(SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
rootcontext = match_strdup(&args[0]);
|
|
if (!rootcontext) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
|
|
case Opt_defcontext:
|
|
if (context || defcontext) {
|
|
rc = -EINVAL;
|
|
pr_warn(SEL_MOUNT_FAIL_MSG);
|
|
goto out_err;
|
|
}
|
|
defcontext = match_strdup(&args[0]);
|
|
if (!defcontext) {
|
|
rc = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
break;
|
|
case Opt_labelsupport:
|
|
break;
|
|
default:
|
|
rc = -EINVAL;
|
|
pr_warn("SELinux: unknown mount option\n");
|
|
goto out_err;
|
|
|
|
}
|
|
}
|
|
|
|
rc = -ENOMEM;
|
|
opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
|
|
if (!opts->mnt_opts)
|
|
goto out_err;
|
|
|
|
opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
|
|
GFP_KERNEL);
|
|
if (!opts->mnt_opts_flags)
|
|
goto out_err;
|
|
|
|
if (fscontext) {
|
|
opts->mnt_opts[num_mnt_opts] = fscontext;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
|
|
}
|
|
if (context) {
|
|
opts->mnt_opts[num_mnt_opts] = context;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
|
|
}
|
|
if (rootcontext) {
|
|
opts->mnt_opts[num_mnt_opts] = rootcontext;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
|
|
}
|
|
if (defcontext) {
|
|
opts->mnt_opts[num_mnt_opts] = defcontext;
|
|
opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
|
|
}
|
|
|
|
opts->num_mnt_opts = num_mnt_opts;
|
|
return 0;
|
|
|
|
out_err:
|
|
security_free_mnt_opts(opts);
|
|
kfree(context);
|
|
kfree(defcontext);
|
|
kfree(fscontext);
|
|
kfree(rootcontext);
|
|
return rc;
|
|
}
|
|
/*
|
|
* string mount options parsing and call set the sbsec
|
|
*/
|
|
static int superblock_doinit(struct super_block *sb, void *data)
|
|
{
|
|
int rc = 0;
|
|
char *options = data;
|
|
struct security_mnt_opts opts;
|
|
|
|
security_init_mnt_opts(&opts);
|
|
|
|
if (!data)
|
|
goto out;
|
|
|
|
BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
|
|
|
|
rc = selinux_parse_opts_str(options, &opts);
|
|
if (rc)
|
|
goto out_err;
|
|
|
|
out:
|
|
rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
|
|
|
|
out_err:
|
|
security_free_mnt_opts(&opts);
|
|
return rc;
|
|
}
|
|
|
|
static void selinux_write_opts(struct seq_file *m,
|
|
struct security_mnt_opts *opts)
|
|
{
|
|
int i;
|
|
char *prefix;
|
|
|
|
for (i = 0; i < opts->num_mnt_opts; i++) {
|
|
char *has_comma;
|
|
|
|
if (opts->mnt_opts[i])
|
|
has_comma = strchr(opts->mnt_opts[i], ',');
|
|
else
|
|
has_comma = NULL;
|
|
|
|
switch (opts->mnt_opts_flags[i]) {
|
|
case CONTEXT_MNT:
|
|
prefix = CONTEXT_STR;
|
|
break;
|
|
case FSCONTEXT_MNT:
|
|
prefix = FSCONTEXT_STR;
|
|
break;
|
|
case ROOTCONTEXT_MNT:
|
|
prefix = ROOTCONTEXT_STR;
|
|
break;
|
|
case DEFCONTEXT_MNT:
|
|
prefix = DEFCONTEXT_STR;
|
|
break;
|
|
case SBLABEL_MNT:
|
|
seq_putc(m, ',');
|
|
seq_puts(m, LABELSUPP_STR);
|
|
continue;
|
|
default:
|
|
BUG();
|
|
return;
|
|
};
|
|
/* we need a comma before each option */
|
|
seq_putc(m, ',');
|
|
seq_puts(m, prefix);
|
|
if (has_comma)
|
|
seq_putc(m, '\"');
|
|
seq_escape(m, opts->mnt_opts[i], "\"\n\\");
|
|
if (has_comma)
|
|
seq_putc(m, '\"');
|
|
}
|
|
}
|
|
|
|
static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
|
|
{
|
|
struct security_mnt_opts opts;
|
|
int rc;
|
|
|
|
rc = selinux_get_mnt_opts(sb, &opts);
|
|
if (rc) {
|
|
/* before policy load we may get EINVAL, don't show anything */
|
|
if (rc == -EINVAL)
|
|
rc = 0;
|
|
return rc;
|
|
}
|
|
|
|
selinux_write_opts(m, &opts);
|
|
|
|
security_free_mnt_opts(&opts);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static inline u16 inode_mode_to_security_class(umode_t mode)
|
|
{
|
|
switch (mode & S_IFMT) {
|
|
case S_IFSOCK:
|
|
return SECCLASS_SOCK_FILE;
|
|
case S_IFLNK:
|
|
return SECCLASS_LNK_FILE;
|
|
case S_IFREG:
|
|
return SECCLASS_FILE;
|
|
case S_IFBLK:
|
|
return SECCLASS_BLK_FILE;
|
|
case S_IFDIR:
|
|
return SECCLASS_DIR;
|
|
case S_IFCHR:
|
|
return SECCLASS_CHR_FILE;
|
|
case S_IFIFO:
|
|
return SECCLASS_FIFO_FILE;
|
|
|
|
}
|
|
|
|
return SECCLASS_FILE;
|
|
}
|
|
|
|
static inline int default_protocol_stream(int protocol)
|
|
{
|
|
return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
|
|
}
|
|
|
|
static inline int default_protocol_dgram(int protocol)
|
|
{
|
|
return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
|
|
}
|
|
|
|
static inline u16 socket_type_to_security_class(int family, int type, int protocol)
|
|
{
|
|
int extsockclass = selinux_policycap_extsockclass();
|
|
|
|
switch (family) {
|
|
case PF_UNIX:
|
|
switch (type) {
|
|
case SOCK_STREAM:
|
|
case SOCK_SEQPACKET:
|
|
return SECCLASS_UNIX_STREAM_SOCKET;
|
|
case SOCK_DGRAM:
|
|
case SOCK_RAW:
|
|
return SECCLASS_UNIX_DGRAM_SOCKET;
|
|
}
|
|
break;
|
|
case PF_INET:
|
|
case PF_INET6:
|
|
switch (type) {
|
|
case SOCK_STREAM:
|
|
case SOCK_SEQPACKET:
|
|
if (default_protocol_stream(protocol))
|
|
return SECCLASS_TCP_SOCKET;
|
|
else if (extsockclass && protocol == IPPROTO_SCTP)
|
|
return SECCLASS_SCTP_SOCKET;
|
|
else
|
|
return SECCLASS_RAWIP_SOCKET;
|
|
case SOCK_DGRAM:
|
|
if (default_protocol_dgram(protocol))
|
|
return SECCLASS_UDP_SOCKET;
|
|
else if (extsockclass && (protocol == IPPROTO_ICMP ||
|
|
protocol == IPPROTO_ICMPV6))
|
|
return SECCLASS_ICMP_SOCKET;
|
|
else
|
|
return SECCLASS_RAWIP_SOCKET;
|
|
case SOCK_DCCP:
|
|
return SECCLASS_DCCP_SOCKET;
|
|
default:
|
|
return SECCLASS_RAWIP_SOCKET;
|
|
}
|
|
break;
|
|
case PF_NETLINK:
|
|
switch (protocol) {
|
|
case NETLINK_ROUTE:
|
|
return SECCLASS_NETLINK_ROUTE_SOCKET;
|
|
case NETLINK_SOCK_DIAG:
|
|
return SECCLASS_NETLINK_TCPDIAG_SOCKET;
|
|
case NETLINK_NFLOG:
|
|
return SECCLASS_NETLINK_NFLOG_SOCKET;
|
|
case NETLINK_XFRM:
|
|
return SECCLASS_NETLINK_XFRM_SOCKET;
|
|
case NETLINK_SELINUX:
|
|
return SECCLASS_NETLINK_SELINUX_SOCKET;
|
|
case NETLINK_ISCSI:
|
|
return SECCLASS_NETLINK_ISCSI_SOCKET;
|
|
case NETLINK_AUDIT:
|
|
return SECCLASS_NETLINK_AUDIT_SOCKET;
|
|
case NETLINK_FIB_LOOKUP:
|
|
return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
|
|
case NETLINK_CONNECTOR:
|
|
return SECCLASS_NETLINK_CONNECTOR_SOCKET;
|
|
case NETLINK_NETFILTER:
|
|
return SECCLASS_NETLINK_NETFILTER_SOCKET;
|
|
case NETLINK_DNRTMSG:
|
|
return SECCLASS_NETLINK_DNRT_SOCKET;
|
|
case NETLINK_KOBJECT_UEVENT:
|
|
return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
|
|
case NETLINK_GENERIC:
|
|
return SECCLASS_NETLINK_GENERIC_SOCKET;
|
|
case NETLINK_SCSITRANSPORT:
|
|
return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
|
|
case NETLINK_RDMA:
|
|
return SECCLASS_NETLINK_RDMA_SOCKET;
|
|
case NETLINK_CRYPTO:
|
|
return SECCLASS_NETLINK_CRYPTO_SOCKET;
|
|
default:
|
|
return SECCLASS_NETLINK_SOCKET;
|
|
}
|
|
case PF_PACKET:
|
|
return SECCLASS_PACKET_SOCKET;
|
|
case PF_KEY:
|
|
return SECCLASS_KEY_SOCKET;
|
|
case PF_APPLETALK:
|
|
return SECCLASS_APPLETALK_SOCKET;
|
|
}
|
|
|
|
if (extsockclass) {
|
|
switch (family) {
|
|
case PF_AX25:
|
|
return SECCLASS_AX25_SOCKET;
|
|
case PF_IPX:
|
|
return SECCLASS_IPX_SOCKET;
|
|
case PF_NETROM:
|
|
return SECCLASS_NETROM_SOCKET;
|
|
case PF_ATMPVC:
|
|
return SECCLASS_ATMPVC_SOCKET;
|
|
case PF_X25:
|
|
return SECCLASS_X25_SOCKET;
|
|
case PF_ROSE:
|
|
return SECCLASS_ROSE_SOCKET;
|
|
case PF_DECnet:
|
|
return SECCLASS_DECNET_SOCKET;
|
|
case PF_ATMSVC:
|
|
return SECCLASS_ATMSVC_SOCKET;
|
|
case PF_RDS:
|
|
return SECCLASS_RDS_SOCKET;
|
|
case PF_IRDA:
|
|
return SECCLASS_IRDA_SOCKET;
|
|
case PF_PPPOX:
|
|
return SECCLASS_PPPOX_SOCKET;
|
|
case PF_LLC:
|
|
return SECCLASS_LLC_SOCKET;
|
|
case PF_CAN:
|
|
return SECCLASS_CAN_SOCKET;
|
|
case PF_TIPC:
|
|
return SECCLASS_TIPC_SOCKET;
|
|
case PF_BLUETOOTH:
|
|
return SECCLASS_BLUETOOTH_SOCKET;
|
|
case PF_IUCV:
|
|
return SECCLASS_IUCV_SOCKET;
|
|
case PF_RXRPC:
|
|
return SECCLASS_RXRPC_SOCKET;
|
|
case PF_ISDN:
|
|
return SECCLASS_ISDN_SOCKET;
|
|
case PF_PHONET:
|
|
return SECCLASS_PHONET_SOCKET;
|
|
case PF_IEEE802154:
|
|
return SECCLASS_IEEE802154_SOCKET;
|
|
case PF_CAIF:
|
|
return SECCLASS_CAIF_SOCKET;
|
|
case PF_ALG:
|
|
return SECCLASS_ALG_SOCKET;
|
|
case PF_NFC:
|
|
return SECCLASS_NFC_SOCKET;
|
|
case PF_VSOCK:
|
|
return SECCLASS_VSOCK_SOCKET;
|
|
case PF_KCM:
|
|
return SECCLASS_KCM_SOCKET;
|
|
case PF_QIPCRTR:
|
|
return SECCLASS_QIPCRTR_SOCKET;
|
|
case PF_SMC:
|
|
return SECCLASS_SMC_SOCKET;
|
|
case PF_XDP:
|
|
return SECCLASS_XDP_SOCKET;
|
|
#if PF_MAX > 45
|
|
#error New address family defined, please update this function.
|
|
#endif
|
|
}
|
|
}
|
|
|
|
return SECCLASS_SOCKET;
|
|
}
|
|
|
|
static int selinux_genfs_get_sid(struct dentry *dentry,
|
|
u16 tclass,
|
|
u16 flags,
|
|
u32 *sid)
|
|
{
|
|
int rc;
|
|
struct super_block *sb = dentry->d_sb;
|
|
char *buffer, *path;
|
|
|
|
buffer = (char *)__get_free_page(GFP_KERNEL);
|
|
if (!buffer)
|
|
return -ENOMEM;
|
|
|
|
path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
|
|
if (IS_ERR(path))
|
|
rc = PTR_ERR(path);
|
|
else {
|
|
if (flags & SE_SBPROC) {
|
|
/* each process gets a /proc/PID/ entry. Strip off the
|
|
* PID part to get a valid selinux labeling.
|
|
* e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
|
|
while (path[1] >= '0' && path[1] <= '9') {
|
|
path[1] = '/';
|
|
path++;
|
|
}
|
|
}
|
|
rc = security_genfs_sid(&selinux_state, sb->s_type->name,
|
|
path, tclass, sid);
|
|
if (rc == -ENOENT) {
|
|
/* No match in policy, mark as unlabeled. */
|
|
*sid = SECINITSID_UNLABELED;
|
|
rc = 0;
|
|
}
|
|
}
|
|
free_page((unsigned long)buffer);
|
|
return rc;
|
|
}
|
|
|
|
/* The inode's security attributes must be initialized before first use. */
|
|
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
|
|
{
|
|
struct superblock_security_struct *sbsec = NULL;
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
u32 task_sid, sid = 0;
|
|
u16 sclass;
|
|
struct dentry *dentry;
|
|
#define INITCONTEXTLEN 255
|
|
char *context = NULL;
|
|
unsigned len = 0;
|
|
int rc = 0;
|
|
|
|
if (isec->initialized == LABEL_INITIALIZED)
|
|
return 0;
|
|
|
|
spin_lock(&isec->lock);
|
|
if (isec->initialized == LABEL_INITIALIZED)
|
|
goto out_unlock;
|
|
|
|
if (isec->sclass == SECCLASS_FILE)
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
|
|
sbsec = inode->i_sb->s_security;
|
|
if (!(sbsec->flags & SE_SBINITIALIZED)) {
|
|
/* Defer initialization until selinux_complete_init,
|
|
after the initial policy is loaded and the security
|
|
server is ready to handle calls. */
|
|
spin_lock(&sbsec->isec_lock);
|
|
if (list_empty(&isec->list))
|
|
list_add(&isec->list, &sbsec->isec_head);
|
|
spin_unlock(&sbsec->isec_lock);
|
|
goto out_unlock;
|
|
}
|
|
|
|
sclass = isec->sclass;
|
|
task_sid = isec->task_sid;
|
|
sid = isec->sid;
|
|
isec->initialized = LABEL_PENDING;
|
|
spin_unlock(&isec->lock);
|
|
|
|
switch (sbsec->behavior) {
|
|
case SECURITY_FS_USE_NATIVE:
|
|
break;
|
|
case SECURITY_FS_USE_XATTR:
|
|
if (!(inode->i_opflags & IOP_XATTR)) {
|
|
sid = sbsec->def_sid;
|
|
break;
|
|
}
|
|
/* Need a dentry, since the xattr API requires one.
|
|
Life would be simpler if we could just pass the inode. */
|
|
if (opt_dentry) {
|
|
/* Called from d_instantiate or d_splice_alias. */
|
|
dentry = dget(opt_dentry);
|
|
} else {
|
|
/*
|
|
* Called from selinux_complete_init, try to find a dentry.
|
|
* Some filesystems really want a connected one, so try
|
|
* that first. We could split SECURITY_FS_USE_XATTR in
|
|
* two, depending upon that...
|
|
*/
|
|
dentry = d_find_alias(inode);
|
|
if (!dentry)
|
|
dentry = d_find_any_alias(inode);
|
|
}
|
|
if (!dentry) {
|
|
/*
|
|
* this is can be hit on boot when a file is accessed
|
|
* before the policy is loaded. When we load policy we
|
|
* may find inodes that have no dentry on the
|
|
* sbsec->isec_head list. No reason to complain as these
|
|
* will get fixed up the next time we go through
|
|
* inode_doinit with a dentry, before these inodes could
|
|
* be used again by userspace.
|
|
*/
|
|
goto out;
|
|
}
|
|
|
|
len = INITCONTEXTLEN;
|
|
context = kmalloc(len+1, GFP_NOFS);
|
|
if (!context) {
|
|
rc = -ENOMEM;
|
|
dput(dentry);
|
|
goto out;
|
|
}
|
|
context[len] = '\0';
|
|
rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
|
|
if (rc == -ERANGE) {
|
|
kfree(context);
|
|
|
|
/* Need a larger buffer. Query for the right size. */
|
|
rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
|
|
if (rc < 0) {
|
|
dput(dentry);
|
|
goto out;
|
|
}
|
|
len = rc;
|
|
context = kmalloc(len+1, GFP_NOFS);
|
|
if (!context) {
|
|
rc = -ENOMEM;
|
|
dput(dentry);
|
|
goto out;
|
|
}
|
|
context[len] = '\0';
|
|
rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
|
|
}
|
|
dput(dentry);
|
|
if (rc < 0) {
|
|
if (rc != -ENODATA) {
|
|
pr_warn("SELinux: %s: getxattr returned "
|
|
"%d for dev=%s ino=%ld\n", __func__,
|
|
-rc, inode->i_sb->s_id, inode->i_ino);
|
|
kfree(context);
|
|
goto out;
|
|
}
|
|
/* Map ENODATA to the default file SID */
|
|
sid = sbsec->def_sid;
|
|
rc = 0;
|
|
} else {
|
|
rc = security_context_to_sid_default(&selinux_state,
|
|
context, rc, &sid,
|
|
sbsec->def_sid,
|
|
GFP_NOFS);
|
|
if (rc) {
|
|
char *dev = inode->i_sb->s_id;
|
|
unsigned long ino = inode->i_ino;
|
|
|
|
if (rc == -EINVAL) {
|
|
if (printk_ratelimit())
|
|
pr_notice("SELinux: inode=%lu on dev=%s was found to have an invalid "
|
|
"context=%s. This indicates you may need to relabel the inode or the "
|
|
"filesystem in question.\n", ino, dev, context);
|
|
} else {
|
|
pr_warn("SELinux: %s: context_to_sid(%s) "
|
|
"returned %d for dev=%s ino=%ld\n",
|
|
__func__, context, -rc, dev, ino);
|
|
}
|
|
kfree(context);
|
|
/* Leave with the unlabeled SID */
|
|
rc = 0;
|
|
break;
|
|
}
|
|
}
|
|
kfree(context);
|
|
break;
|
|
case SECURITY_FS_USE_TASK:
|
|
sid = task_sid;
|
|
break;
|
|
case SECURITY_FS_USE_TRANS:
|
|
/* Default to the fs SID. */
|
|
sid = sbsec->sid;
|
|
|
|
/* Try to obtain a transition SID. */
|
|
rc = security_transition_sid(&selinux_state, task_sid, sid,
|
|
sclass, NULL, &sid);
|
|
if (rc)
|
|
goto out;
|
|
break;
|
|
case SECURITY_FS_USE_MNTPOINT:
|
|
sid = sbsec->mntpoint_sid;
|
|
break;
|
|
default:
|
|
/* Default to the fs superblock SID. */
|
|
sid = sbsec->sid;
|
|
|
|
if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
|
|
/* We must have a dentry to determine the label on
|
|
* procfs inodes */
|
|
if (opt_dentry) {
|
|
/* Called from d_instantiate or
|
|
* d_splice_alias. */
|
|
dentry = dget(opt_dentry);
|
|
} else {
|
|
/* Called from selinux_complete_init, try to
|
|
* find a dentry. Some filesystems really want
|
|
* a connected one, so try that first.
|
|
*/
|
|
dentry = d_find_alias(inode);
|
|
if (!dentry)
|
|
dentry = d_find_any_alias(inode);
|
|
}
|
|
/*
|
|
* This can be hit on boot when a file is accessed
|
|
* before the policy is loaded. When we load policy we
|
|
* may find inodes that have no dentry on the
|
|
* sbsec->isec_head list. No reason to complain as
|
|
* these will get fixed up the next time we go through
|
|
* inode_doinit() with a dentry, before these inodes
|
|
* could be used again by userspace.
|
|
*/
|
|
if (!dentry)
|
|
goto out;
|
|
rc = selinux_genfs_get_sid(dentry, sclass,
|
|
sbsec->flags, &sid);
|
|
dput(dentry);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
break;
|
|
}
|
|
|
|
out:
|
|
spin_lock(&isec->lock);
|
|
if (isec->initialized == LABEL_PENDING) {
|
|
if (!sid || rc) {
|
|
isec->initialized = LABEL_INVALID;
|
|
goto out_unlock;
|
|
}
|
|
|
|
isec->initialized = LABEL_INITIALIZED;
|
|
isec->sid = sid;
|
|
}
|
|
|
|
out_unlock:
|
|
spin_unlock(&isec->lock);
|
|
return rc;
|
|
}
|
|
|
|
/* Convert a Linux signal to an access vector. */
|
|
static inline u32 signal_to_av(int sig)
|
|
{
|
|
u32 perm = 0;
|
|
|
|
switch (sig) {
|
|
case SIGCHLD:
|
|
/* Commonly granted from child to parent. */
|
|
perm = PROCESS__SIGCHLD;
|
|
break;
|
|
case SIGKILL:
|
|
/* Cannot be caught or ignored */
|
|
perm = PROCESS__SIGKILL;
|
|
break;
|
|
case SIGSTOP:
|
|
/* Cannot be caught or ignored */
|
|
perm = PROCESS__SIGSTOP;
|
|
break;
|
|
default:
|
|
/* All other signals. */
|
|
perm = PROCESS__SIGNAL;
|
|
break;
|
|
}
|
|
|
|
return perm;
|
|
}
|
|
|
|
#if CAP_LAST_CAP > 63
|
|
#error Fix SELinux to handle capabilities > 63.
|
|
#endif
|
|
|
|
/* Check whether a task is allowed to use a capability. */
|
|
static int cred_has_capability(const struct cred *cred,
|
|
int cap, int audit, bool initns)
|
|
{
|
|
struct common_audit_data ad;
|
|
struct av_decision avd;
|
|
u16 sclass;
|
|
u32 sid = cred_sid(cred);
|
|
u32 av = CAP_TO_MASK(cap);
|
|
int rc;
|
|
|
|
ad.type = LSM_AUDIT_DATA_CAP;
|
|
ad.u.cap = cap;
|
|
|
|
switch (CAP_TO_INDEX(cap)) {
|
|
case 0:
|
|
sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
|
|
break;
|
|
case 1:
|
|
sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
|
|
break;
|
|
default:
|
|
pr_err("SELinux: out of range capability %d\n", cap);
|
|
BUG();
|
|
return -EINVAL;
|
|
}
|
|
|
|
rc = avc_has_perm_noaudit(&selinux_state,
|
|
sid, sid, sclass, av, 0, &avd);
|
|
if (audit == SECURITY_CAP_AUDIT) {
|
|
int rc2 = avc_audit(&selinux_state,
|
|
sid, sid, sclass, av, &avd, rc, &ad, 0);
|
|
if (rc2)
|
|
return rc2;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
/* Check whether a task has a particular permission to an inode.
|
|
The 'adp' parameter is optional and allows other audit
|
|
data to be passed (e.g. the dentry). */
|
|
static int inode_has_perm(const struct cred *cred,
|
|
struct inode *inode,
|
|
u32 perms,
|
|
struct common_audit_data *adp)
|
|
{
|
|
struct inode_security_struct *isec;
|
|
u32 sid;
|
|
|
|
validate_creds(cred);
|
|
|
|
if (unlikely(IS_PRIVATE(inode)))
|
|
return 0;
|
|
|
|
sid = cred_sid(cred);
|
|
isec = inode->i_security;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, isec->sid, isec->sclass, perms, adp);
|
|
}
|
|
|
|
/* Same as inode_has_perm, but pass explicit audit data containing
|
|
the dentry to help the auditing code to more easily generate the
|
|
pathname if needed. */
|
|
static inline int dentry_has_perm(const struct cred *cred,
|
|
struct dentry *dentry,
|
|
u32 av)
|
|
{
|
|
struct inode *inode = d_backing_inode(dentry);
|
|
struct common_audit_data ad;
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
ad.u.dentry = dentry;
|
|
__inode_security_revalidate(inode, dentry, true);
|
|
return inode_has_perm(cred, inode, av, &ad);
|
|
}
|
|
|
|
/* Same as inode_has_perm, but pass explicit audit data containing
|
|
the path to help the auditing code to more easily generate the
|
|
pathname if needed. */
|
|
static inline int path_has_perm(const struct cred *cred,
|
|
const struct path *path,
|
|
u32 av)
|
|
{
|
|
struct inode *inode = d_backing_inode(path->dentry);
|
|
struct common_audit_data ad;
|
|
|
|
ad.type = LSM_AUDIT_DATA_PATH;
|
|
ad.u.path = *path;
|
|
__inode_security_revalidate(inode, path->dentry, true);
|
|
return inode_has_perm(cred, inode, av, &ad);
|
|
}
|
|
|
|
/* Same as path_has_perm, but uses the inode from the file struct. */
|
|
static inline int file_path_has_perm(const struct cred *cred,
|
|
struct file *file,
|
|
u32 av)
|
|
{
|
|
struct common_audit_data ad;
|
|
|
|
ad.type = LSM_AUDIT_DATA_FILE;
|
|
ad.u.file = file;
|
|
return inode_has_perm(cred, file_inode(file), av, &ad);
|
|
}
|
|
|
|
#ifdef CONFIG_BPF_SYSCALL
|
|
static int bpf_fd_pass(struct file *file, u32 sid);
|
|
#endif
|
|
|
|
/* Check whether a task can use an open file descriptor to
|
|
access an inode in a given way. Check access to the
|
|
descriptor itself, and then use dentry_has_perm to
|
|
check a particular permission to the file.
|
|
Access to the descriptor is implicitly granted if it
|
|
has the same SID as the process. If av is zero, then
|
|
access to the file is not checked, e.g. for cases
|
|
where only the descriptor is affected like seek. */
|
|
static int file_has_perm(const struct cred *cred,
|
|
struct file *file,
|
|
u32 av)
|
|
{
|
|
struct file_security_struct *fsec = file->f_security;
|
|
struct inode *inode = file_inode(file);
|
|
struct common_audit_data ad;
|
|
u32 sid = cred_sid(cred);
|
|
int rc;
|
|
|
|
ad.type = LSM_AUDIT_DATA_FILE;
|
|
ad.u.file = file;
|
|
|
|
if (sid != fsec->sid) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, fsec->sid,
|
|
SECCLASS_FD,
|
|
FD__USE,
|
|
&ad);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
#ifdef CONFIG_BPF_SYSCALL
|
|
rc = bpf_fd_pass(file, cred_sid(cred));
|
|
if (rc)
|
|
return rc;
|
|
#endif
|
|
|
|
/* av is zero if only checking access to the descriptor. */
|
|
rc = 0;
|
|
if (av)
|
|
rc = inode_has_perm(cred, inode, av, &ad);
|
|
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Determine the label for an inode that might be unioned.
|
|
*/
|
|
static int
|
|
selinux_determine_inode_label(const struct task_security_struct *tsec,
|
|
struct inode *dir,
|
|
const struct qstr *name, u16 tclass,
|
|
u32 *_new_isid)
|
|
{
|
|
const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
|
|
|
|
if ((sbsec->flags & SE_SBINITIALIZED) &&
|
|
(sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
|
|
*_new_isid = sbsec->mntpoint_sid;
|
|
} else if ((sbsec->flags & SBLABEL_MNT) &&
|
|
tsec->create_sid) {
|
|
*_new_isid = tsec->create_sid;
|
|
} else {
|
|
const struct inode_security_struct *dsec = inode_security(dir);
|
|
return security_transition_sid(&selinux_state, tsec->sid,
|
|
dsec->sid, tclass,
|
|
name, _new_isid);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Check whether a task can create a file. */
|
|
static int may_create(struct inode *dir,
|
|
struct dentry *dentry,
|
|
u16 tclass)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct inode_security_struct *dsec;
|
|
struct superblock_security_struct *sbsec;
|
|
u32 sid, newsid;
|
|
struct common_audit_data ad;
|
|
int rc;
|
|
|
|
dsec = inode_security(dir);
|
|
sbsec = dir->i_sb->s_security;
|
|
|
|
sid = tsec->sid;
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
ad.u.dentry = dentry;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, dsec->sid, SECCLASS_DIR,
|
|
DIR__ADD_NAME | DIR__SEARCH,
|
|
&ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = selinux_determine_inode_label(current_security(), dir,
|
|
&dentry->d_name, tclass, &newsid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, newsid, tclass, FILE__CREATE, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
newsid, sbsec->sid,
|
|
SECCLASS_FILESYSTEM,
|
|
FILESYSTEM__ASSOCIATE, &ad);
|
|
}
|
|
|
|
#define MAY_LINK 0
|
|
#define MAY_UNLINK 1
|
|
#define MAY_RMDIR 2
|
|
|
|
/* Check whether a task can link, unlink, or rmdir a file/directory. */
|
|
static int may_link(struct inode *dir,
|
|
struct dentry *dentry,
|
|
int kind)
|
|
|
|
{
|
|
struct inode_security_struct *dsec, *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
u32 av;
|
|
int rc;
|
|
|
|
dsec = inode_security(dir);
|
|
isec = backing_inode_security(dentry);
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
ad.u.dentry = dentry;
|
|
|
|
av = DIR__SEARCH;
|
|
av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, dsec->sid, SECCLASS_DIR, av, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
switch (kind) {
|
|
case MAY_LINK:
|
|
av = FILE__LINK;
|
|
break;
|
|
case MAY_UNLINK:
|
|
av = FILE__UNLINK;
|
|
break;
|
|
case MAY_RMDIR:
|
|
av = DIR__RMDIR;
|
|
break;
|
|
default:
|
|
pr_warn("SELinux: %s: unrecognized kind %d\n",
|
|
__func__, kind);
|
|
return 0;
|
|
}
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, isec->sid, isec->sclass, av, &ad);
|
|
return rc;
|
|
}
|
|
|
|
static inline int may_rename(struct inode *old_dir,
|
|
struct dentry *old_dentry,
|
|
struct inode *new_dir,
|
|
struct dentry *new_dentry)
|
|
{
|
|
struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
u32 av;
|
|
int old_is_dir, new_is_dir;
|
|
int rc;
|
|
|
|
old_dsec = inode_security(old_dir);
|
|
old_isec = backing_inode_security(old_dentry);
|
|
old_is_dir = d_is_dir(old_dentry);
|
|
new_dsec = inode_security(new_dir);
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
|
|
ad.u.dentry = old_dentry;
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, old_dsec->sid, SECCLASS_DIR,
|
|
DIR__REMOVE_NAME | DIR__SEARCH, &ad);
|
|
if (rc)
|
|
return rc;
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, old_isec->sid,
|
|
old_isec->sclass, FILE__RENAME, &ad);
|
|
if (rc)
|
|
return rc;
|
|
if (old_is_dir && new_dir != old_dir) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, old_isec->sid,
|
|
old_isec->sclass, DIR__REPARENT, &ad);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
ad.u.dentry = new_dentry;
|
|
av = DIR__ADD_NAME | DIR__SEARCH;
|
|
if (d_is_positive(new_dentry))
|
|
av |= DIR__REMOVE_NAME;
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
|
|
if (rc)
|
|
return rc;
|
|
if (d_is_positive(new_dentry)) {
|
|
new_isec = backing_inode_security(new_dentry);
|
|
new_is_dir = d_is_dir(new_dentry);
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, new_isec->sid,
|
|
new_isec->sclass,
|
|
(new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Check whether a task can perform a filesystem operation. */
|
|
static int superblock_has_perm(const struct cred *cred,
|
|
struct super_block *sb,
|
|
u32 perms,
|
|
struct common_audit_data *ad)
|
|
{
|
|
struct superblock_security_struct *sbsec;
|
|
u32 sid = cred_sid(cred);
|
|
|
|
sbsec = sb->s_security;
|
|
return avc_has_perm(&selinux_state,
|
|
sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
|
|
}
|
|
|
|
/* Convert a Linux mode and permission mask to an access vector. */
|
|
static inline u32 file_mask_to_av(int mode, int mask)
|
|
{
|
|
u32 av = 0;
|
|
|
|
if (!S_ISDIR(mode)) {
|
|
if (mask & MAY_EXEC)
|
|
av |= FILE__EXECUTE;
|
|
if (mask & MAY_READ)
|
|
av |= FILE__READ;
|
|
|
|
if (mask & MAY_APPEND)
|
|
av |= FILE__APPEND;
|
|
else if (mask & MAY_WRITE)
|
|
av |= FILE__WRITE;
|
|
|
|
} else {
|
|
if (mask & MAY_EXEC)
|
|
av |= DIR__SEARCH;
|
|
if (mask & MAY_WRITE)
|
|
av |= DIR__WRITE;
|
|
if (mask & MAY_READ)
|
|
av |= DIR__READ;
|
|
}
|
|
|
|
return av;
|
|
}
|
|
|
|
/* Convert a Linux file to an access vector. */
|
|
static inline u32 file_to_av(struct file *file)
|
|
{
|
|
u32 av = 0;
|
|
|
|
if (file->f_mode & FMODE_READ)
|
|
av |= FILE__READ;
|
|
if (file->f_mode & FMODE_WRITE) {
|
|
if (file->f_flags & O_APPEND)
|
|
av |= FILE__APPEND;
|
|
else
|
|
av |= FILE__WRITE;
|
|
}
|
|
if (!av) {
|
|
/*
|
|
* Special file opened with flags 3 for ioctl-only use.
|
|
*/
|
|
av = FILE__IOCTL;
|
|
}
|
|
|
|
return av;
|
|
}
|
|
|
|
/*
|
|
* Convert a file to an access vector and include the correct open
|
|
* open permission.
|
|
*/
|
|
static inline u32 open_file_to_av(struct file *file)
|
|
{
|
|
u32 av = file_to_av(file);
|
|
struct inode *inode = file_inode(file);
|
|
|
|
if (selinux_policycap_openperm() &&
|
|
inode->i_sb->s_magic != SOCKFS_MAGIC)
|
|
av |= FILE__OPEN;
|
|
|
|
return av;
|
|
}
|
|
|
|
/* Hook functions begin here. */
|
|
|
|
static int selinux_binder_set_context_mgr(struct task_struct *mgr)
|
|
{
|
|
u32 mysid = current_sid();
|
|
u32 mgrsid = task_sid(mgr);
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
mysid, mgrsid, SECCLASS_BINDER,
|
|
BINDER__SET_CONTEXT_MGR, NULL);
|
|
}
|
|
|
|
static int selinux_binder_transaction(struct task_struct *from,
|
|
struct task_struct *to)
|
|
{
|
|
u32 mysid = current_sid();
|
|
u32 fromsid = task_sid(from);
|
|
u32 tosid = task_sid(to);
|
|
int rc;
|
|
|
|
if (mysid != fromsid) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
mysid, fromsid, SECCLASS_BINDER,
|
|
BINDER__IMPERSONATE, NULL);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
|
|
NULL);
|
|
}
|
|
|
|
static int selinux_binder_transfer_binder(struct task_struct *from,
|
|
struct task_struct *to)
|
|
{
|
|
u32 fromsid = task_sid(from);
|
|
u32 tosid = task_sid(to);
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
|
|
NULL);
|
|
}
|
|
|
|
static int selinux_binder_transfer_file(struct task_struct *from,
|
|
struct task_struct *to,
|
|
struct file *file)
|
|
{
|
|
u32 sid = task_sid(to);
|
|
struct file_security_struct *fsec = file->f_security;
|
|
struct dentry *dentry = file->f_path.dentry;
|
|
struct inode_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
int rc;
|
|
|
|
ad.type = LSM_AUDIT_DATA_PATH;
|
|
ad.u.path = file->f_path;
|
|
|
|
if (sid != fsec->sid) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, fsec->sid,
|
|
SECCLASS_FD,
|
|
FD__USE,
|
|
&ad);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
#ifdef CONFIG_BPF_SYSCALL
|
|
rc = bpf_fd_pass(file, sid);
|
|
if (rc)
|
|
return rc;
|
|
#endif
|
|
|
|
if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
|
|
return 0;
|
|
|
|
isec = backing_inode_security(dentry);
|
|
return avc_has_perm(&selinux_state,
|
|
sid, isec->sid, isec->sclass, file_to_av(file),
|
|
&ad);
|
|
}
|
|
|
|
static int selinux_ptrace_access_check(struct task_struct *child,
|
|
unsigned int mode)
|
|
{
|
|
u32 sid = current_sid();
|
|
u32 csid = task_sid(child);
|
|
|
|
if (mode & PTRACE_MODE_READ)
|
|
return avc_has_perm(&selinux_state,
|
|
sid, csid, SECCLASS_FILE, FILE__READ, NULL);
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
|
|
}
|
|
|
|
static int selinux_ptrace_traceme(struct task_struct *parent)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
task_sid(parent), current_sid(), SECCLASS_PROCESS,
|
|
PROCESS__PTRACE, NULL);
|
|
}
|
|
|
|
static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
|
|
kernel_cap_t *inheritable, kernel_cap_t *permitted)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(target), SECCLASS_PROCESS,
|
|
PROCESS__GETCAP, NULL);
|
|
}
|
|
|
|
static int selinux_capset(struct cred *new, const struct cred *old,
|
|
const kernel_cap_t *effective,
|
|
const kernel_cap_t *inheritable,
|
|
const kernel_cap_t *permitted)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
|
|
PROCESS__SETCAP, NULL);
|
|
}
|
|
|
|
/*
|
|
* (This comment used to live with the selinux_task_setuid hook,
|
|
* which was removed).
|
|
*
|
|
* Since setuid only affects the current process, and since the SELinux
|
|
* controls are not based on the Linux identity attributes, SELinux does not
|
|
* need to control this operation. However, SELinux does control the use of
|
|
* the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
|
|
*/
|
|
|
|
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
|
|
int cap, int audit)
|
|
{
|
|
return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
|
|
}
|
|
|
|
static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int rc = 0;
|
|
|
|
if (!sb)
|
|
return 0;
|
|
|
|
switch (cmds) {
|
|
case Q_SYNC:
|
|
case Q_QUOTAON:
|
|
case Q_QUOTAOFF:
|
|
case Q_SETINFO:
|
|
case Q_SETQUOTA:
|
|
rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
|
|
break;
|
|
case Q_GETFMT:
|
|
case Q_GETINFO:
|
|
case Q_GETQUOTA:
|
|
rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
|
|
break;
|
|
default:
|
|
rc = 0; /* let the kernel handle invalid cmds */
|
|
break;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_quota_on(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__QUOTAON);
|
|
}
|
|
|
|
static int selinux_syslog(int type)
|
|
{
|
|
switch (type) {
|
|
case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
|
|
case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), SECINITSID_KERNEL,
|
|
SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
|
|
case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
|
|
case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
|
|
/* Set level of messages printed to console */
|
|
case SYSLOG_ACTION_CONSOLE_LEVEL:
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), SECINITSID_KERNEL,
|
|
SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
|
|
NULL);
|
|
}
|
|
/* All other syslog types */
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), SECINITSID_KERNEL,
|
|
SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
|
|
}
|
|
|
|
/*
|
|
* Check that a process has enough memory to allocate a new virtual
|
|
* mapping. 0 means there is enough memory for the allocation to
|
|
* succeed and -ENOMEM implies there is not.
|
|
*
|
|
* Do not audit the selinux permission check, as this is applied to all
|
|
* processes that allocate mappings.
|
|
*/
|
|
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
|
|
{
|
|
int rc, cap_sys_admin = 0;
|
|
|
|
rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
|
|
SECURITY_CAP_NOAUDIT, true);
|
|
if (rc == 0)
|
|
cap_sys_admin = 1;
|
|
|
|
return cap_sys_admin;
|
|
}
|
|
|
|
/* binprm security operations */
|
|
|
|
static u32 ptrace_parent_sid(void)
|
|
{
|
|
u32 sid = 0;
|
|
struct task_struct *tracer;
|
|
|
|
rcu_read_lock();
|
|
tracer = ptrace_parent(current);
|
|
if (tracer)
|
|
sid = task_sid(tracer);
|
|
rcu_read_unlock();
|
|
|
|
return sid;
|
|
}
|
|
|
|
static int check_nnp_nosuid(const struct linux_binprm *bprm,
|
|
const struct task_security_struct *old_tsec,
|
|
const struct task_security_struct *new_tsec)
|
|
{
|
|
int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
|
|
int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
|
|
int rc;
|
|
u32 av;
|
|
|
|
if (!nnp && !nosuid)
|
|
return 0; /* neither NNP nor nosuid */
|
|
|
|
if (new_tsec->sid == old_tsec->sid)
|
|
return 0; /* No change in credentials */
|
|
|
|
/*
|
|
* If the policy enables the nnp_nosuid_transition policy capability,
|
|
* then we permit transitions under NNP or nosuid if the
|
|
* policy allows the corresponding permission between
|
|
* the old and new contexts.
|
|
*/
|
|
if (selinux_policycap_nnp_nosuid_transition()) {
|
|
av = 0;
|
|
if (nnp)
|
|
av |= PROCESS2__NNP_TRANSITION;
|
|
if (nosuid)
|
|
av |= PROCESS2__NOSUID_TRANSITION;
|
|
rc = avc_has_perm(&selinux_state,
|
|
old_tsec->sid, new_tsec->sid,
|
|
SECCLASS_PROCESS2, av, NULL);
|
|
if (!rc)
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* We also permit NNP or nosuid transitions to bounded SIDs,
|
|
* i.e. SIDs that are guaranteed to only be allowed a subset
|
|
* of the permissions of the current SID.
|
|
*/
|
|
rc = security_bounded_transition(&selinux_state, old_tsec->sid,
|
|
new_tsec->sid);
|
|
if (!rc)
|
|
return 0;
|
|
|
|
/*
|
|
* On failure, preserve the errno values for NNP vs nosuid.
|
|
* NNP: Operation not permitted for caller.
|
|
* nosuid: Permission denied to file.
|
|
*/
|
|
if (nnp)
|
|
return -EPERM;
|
|
return -EACCES;
|
|
}
|
|
|
|
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
|
|
{
|
|
const struct task_security_struct *old_tsec;
|
|
struct task_security_struct *new_tsec;
|
|
struct inode_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
struct inode *inode = file_inode(bprm->file);
|
|
int rc;
|
|
|
|
/* SELinux context only depends on initial program or script and not
|
|
* the script interpreter */
|
|
if (bprm->called_set_creds)
|
|
return 0;
|
|
|
|
old_tsec = current_security();
|
|
new_tsec = bprm->cred->security;
|
|
isec = inode_security(inode);
|
|
|
|
/* Default to the current task SID. */
|
|
new_tsec->sid = old_tsec->sid;
|
|
new_tsec->osid = old_tsec->sid;
|
|
|
|
/* Reset fs, key, and sock SIDs on execve. */
|
|
new_tsec->create_sid = 0;
|
|
new_tsec->keycreate_sid = 0;
|
|
new_tsec->sockcreate_sid = 0;
|
|
|
|
if (old_tsec->exec_sid) {
|
|
new_tsec->sid = old_tsec->exec_sid;
|
|
/* Reset exec SID on execve. */
|
|
new_tsec->exec_sid = 0;
|
|
|
|
/* Fail on NNP or nosuid if not an allowed transition. */
|
|
rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
|
|
if (rc)
|
|
return rc;
|
|
} else {
|
|
/* Check for a default transition on this program. */
|
|
rc = security_transition_sid(&selinux_state, old_tsec->sid,
|
|
isec->sid, SECCLASS_PROCESS, NULL,
|
|
&new_tsec->sid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/*
|
|
* Fallback to old SID on NNP or nosuid if not an allowed
|
|
* transition.
|
|
*/
|
|
rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
|
|
if (rc)
|
|
new_tsec->sid = old_tsec->sid;
|
|
}
|
|
|
|
ad.type = LSM_AUDIT_DATA_FILE;
|
|
ad.u.file = bprm->file;
|
|
|
|
if (new_tsec->sid == old_tsec->sid) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
old_tsec->sid, isec->sid,
|
|
SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
|
|
if (rc)
|
|
return rc;
|
|
} else {
|
|
/* Check permissions for the transition. */
|
|
rc = avc_has_perm(&selinux_state,
|
|
old_tsec->sid, new_tsec->sid,
|
|
SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
new_tsec->sid, isec->sid,
|
|
SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Check for shared state */
|
|
if (bprm->unsafe & LSM_UNSAFE_SHARE) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
old_tsec->sid, new_tsec->sid,
|
|
SECCLASS_PROCESS, PROCESS__SHARE,
|
|
NULL);
|
|
if (rc)
|
|
return -EPERM;
|
|
}
|
|
|
|
/* Make sure that anyone attempting to ptrace over a task that
|
|
* changes its SID has the appropriate permit */
|
|
if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
|
|
u32 ptsid = ptrace_parent_sid();
|
|
if (ptsid != 0) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
ptsid, new_tsec->sid,
|
|
SECCLASS_PROCESS,
|
|
PROCESS__PTRACE, NULL);
|
|
if (rc)
|
|
return -EPERM;
|
|
}
|
|
}
|
|
|
|
/* Clear any possibly unsafe personality bits on exec: */
|
|
bprm->per_clear |= PER_CLEAR_ON_SETID;
|
|
|
|
/* Enable secure mode for SIDs transitions unless
|
|
the noatsecure permission is granted between
|
|
the two SIDs, i.e. ahp returns 0. */
|
|
rc = avc_has_perm(&selinux_state,
|
|
old_tsec->sid, new_tsec->sid,
|
|
SECCLASS_PROCESS, PROCESS__NOATSECURE,
|
|
NULL);
|
|
bprm->secureexec |= !!rc;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int match_file(const void *p, struct file *file, unsigned fd)
|
|
{
|
|
return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
|
|
}
|
|
|
|
/* Derived from fs/exec.c:flush_old_files. */
|
|
static inline void flush_unauthorized_files(const struct cred *cred,
|
|
struct files_struct *files)
|
|
{
|
|
struct file *file, *devnull = NULL;
|
|
struct tty_struct *tty;
|
|
int drop_tty = 0;
|
|
unsigned n;
|
|
|
|
tty = get_current_tty();
|
|
if (tty) {
|
|
spin_lock(&tty->files_lock);
|
|
if (!list_empty(&tty->tty_files)) {
|
|
struct tty_file_private *file_priv;
|
|
|
|
/* Revalidate access to controlling tty.
|
|
Use file_path_has_perm on the tty path directly
|
|
rather than using file_has_perm, as this particular
|
|
open file may belong to another process and we are
|
|
only interested in the inode-based check here. */
|
|
file_priv = list_first_entry(&tty->tty_files,
|
|
struct tty_file_private, list);
|
|
file = file_priv->file;
|
|
if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
|
|
drop_tty = 1;
|
|
}
|
|
spin_unlock(&tty->files_lock);
|
|
tty_kref_put(tty);
|
|
}
|
|
/* Reset controlling tty. */
|
|
if (drop_tty)
|
|
no_tty();
|
|
|
|
/* Revalidate access to inherited open files. */
|
|
n = iterate_fd(files, 0, match_file, cred);
|
|
if (!n) /* none found? */
|
|
return;
|
|
|
|
devnull = dentry_open(&selinux_null, O_RDWR, cred);
|
|
if (IS_ERR(devnull))
|
|
devnull = NULL;
|
|
/* replace all the matching ones with this */
|
|
do {
|
|
replace_fd(n - 1, devnull, 0);
|
|
} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
|
|
if (devnull)
|
|
fput(devnull);
|
|
}
|
|
|
|
/*
|
|
* Prepare a process for imminent new credential changes due to exec
|
|
*/
|
|
static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
|
|
{
|
|
struct task_security_struct *new_tsec;
|
|
struct rlimit *rlim, *initrlim;
|
|
int rc, i;
|
|
|
|
new_tsec = bprm->cred->security;
|
|
if (new_tsec->sid == new_tsec->osid)
|
|
return;
|
|
|
|
/* Close files for which the new task SID is not authorized. */
|
|
flush_unauthorized_files(bprm->cred, current->files);
|
|
|
|
/* Always clear parent death signal on SID transitions. */
|
|
current->pdeath_signal = 0;
|
|
|
|
/* Check whether the new SID can inherit resource limits from the old
|
|
* SID. If not, reset all soft limits to the lower of the current
|
|
* task's hard limit and the init task's soft limit.
|
|
*
|
|
* Note that the setting of hard limits (even to lower them) can be
|
|
* controlled by the setrlimit check. The inclusion of the init task's
|
|
* soft limit into the computation is to avoid resetting soft limits
|
|
* higher than the default soft limit for cases where the default is
|
|
* lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
|
|
*/
|
|
rc = avc_has_perm(&selinux_state,
|
|
new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
|
|
PROCESS__RLIMITINH, NULL);
|
|
if (rc) {
|
|
/* protect against do_prlimit() */
|
|
task_lock(current);
|
|
for (i = 0; i < RLIM_NLIMITS; i++) {
|
|
rlim = current->signal->rlim + i;
|
|
initrlim = init_task.signal->rlim + i;
|
|
rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
|
|
}
|
|
task_unlock(current);
|
|
if (IS_ENABLED(CONFIG_POSIX_TIMERS))
|
|
update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Clean up the process immediately after the installation of new credentials
|
|
* due to exec
|
|
*/
|
|
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct itimerval itimer;
|
|
u32 osid, sid;
|
|
int rc, i;
|
|
|
|
osid = tsec->osid;
|
|
sid = tsec->sid;
|
|
|
|
if (sid == osid)
|
|
return;
|
|
|
|
/* Check whether the new SID can inherit signal state from the old SID.
|
|
* If not, clear itimers to avoid subsequent signal generation and
|
|
* flush and unblock signals.
|
|
*
|
|
* This must occur _after_ the task SID has been updated so that any
|
|
* kill done after the flush will be checked against the new SID.
|
|
*/
|
|
rc = avc_has_perm(&selinux_state,
|
|
osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
|
|
if (rc) {
|
|
if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
|
|
memset(&itimer, 0, sizeof itimer);
|
|
for (i = 0; i < 3; i++)
|
|
do_setitimer(i, &itimer, NULL);
|
|
}
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
if (!fatal_signal_pending(current)) {
|
|
flush_sigqueue(¤t->pending);
|
|
flush_sigqueue(¤t->signal->shared_pending);
|
|
flush_signal_handlers(current, 1);
|
|
sigemptyset(¤t->blocked);
|
|
recalc_sigpending();
|
|
}
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
}
|
|
|
|
/* Wake up the parent if it is waiting so that it can recheck
|
|
* wait permission to the new task SID. */
|
|
read_lock(&tasklist_lock);
|
|
__wake_up_parent(current, current->real_parent);
|
|
read_unlock(&tasklist_lock);
|
|
}
|
|
|
|
/* superblock security operations */
|
|
|
|
static int selinux_sb_alloc_security(struct super_block *sb)
|
|
{
|
|
return superblock_alloc_security(sb);
|
|
}
|
|
|
|
static void selinux_sb_free_security(struct super_block *sb)
|
|
{
|
|
superblock_free_security(sb);
|
|
}
|
|
|
|
static inline int match_prefix(char *prefix, int plen, char *option, int olen)
|
|
{
|
|
if (plen > olen)
|
|
return 0;
|
|
|
|
return !memcmp(prefix, option, plen);
|
|
}
|
|
|
|
static inline int selinux_option(char *option, int len)
|
|
{
|
|
return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
|
|
match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
|
|
match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
|
|
match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
|
|
match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
|
|
}
|
|
|
|
static inline void take_option(char **to, char *from, int *first, int len)
|
|
{
|
|
if (!*first) {
|
|
**to = ',';
|
|
*to += 1;
|
|
} else
|
|
*first = 0;
|
|
memcpy(*to, from, len);
|
|
*to += len;
|
|
}
|
|
|
|
static inline void take_selinux_option(char **to, char *from, int *first,
|
|
int len)
|
|
{
|
|
int current_size = 0;
|
|
|
|
if (!*first) {
|
|
**to = '|';
|
|
*to += 1;
|
|
} else
|
|
*first = 0;
|
|
|
|
while (current_size < len) {
|
|
if (*from != '"') {
|
|
**to = *from;
|
|
*to += 1;
|
|
}
|
|
from += 1;
|
|
current_size += 1;
|
|
}
|
|
}
|
|
|
|
static int selinux_sb_copy_data(char *orig, char *copy)
|
|
{
|
|
int fnosec, fsec, rc = 0;
|
|
char *in_save, *in_curr, *in_end;
|
|
char *sec_curr, *nosec_save, *nosec;
|
|
int open_quote = 0;
|
|
|
|
in_curr = orig;
|
|
sec_curr = copy;
|
|
|
|
nosec = (char *)get_zeroed_page(GFP_KERNEL);
|
|
if (!nosec) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
nosec_save = nosec;
|
|
fnosec = fsec = 1;
|
|
in_save = in_end = orig;
|
|
|
|
do {
|
|
if (*in_end == '"')
|
|
open_quote = !open_quote;
|
|
if ((*in_end == ',' && open_quote == 0) ||
|
|
*in_end == '\0') {
|
|
int len = in_end - in_curr;
|
|
|
|
if (selinux_option(in_curr, len))
|
|
take_selinux_option(&sec_curr, in_curr, &fsec, len);
|
|
else
|
|
take_option(&nosec, in_curr, &fnosec, len);
|
|
|
|
in_curr = in_end + 1;
|
|
}
|
|
} while (*in_end++);
|
|
|
|
strcpy(in_save, nosec_save);
|
|
free_page((unsigned long)nosec_save);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_sb_remount(struct super_block *sb, void *data)
|
|
{
|
|
int rc, i, *flags;
|
|
struct security_mnt_opts opts;
|
|
char *secdata, **mount_options;
|
|
struct superblock_security_struct *sbsec = sb->s_security;
|
|
|
|
if (!(sbsec->flags & SE_SBINITIALIZED))
|
|
return 0;
|
|
|
|
if (!data)
|
|
return 0;
|
|
|
|
if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
|
|
return 0;
|
|
|
|
security_init_mnt_opts(&opts);
|
|
secdata = alloc_secdata();
|
|
if (!secdata)
|
|
return -ENOMEM;
|
|
rc = selinux_sb_copy_data(data, secdata);
|
|
if (rc)
|
|
goto out_free_secdata;
|
|
|
|
rc = selinux_parse_opts_str(secdata, &opts);
|
|
if (rc)
|
|
goto out_free_secdata;
|
|
|
|
mount_options = opts.mnt_opts;
|
|
flags = opts.mnt_opts_flags;
|
|
|
|
for (i = 0; i < opts.num_mnt_opts; i++) {
|
|
u32 sid;
|
|
|
|
if (flags[i] == SBLABEL_MNT)
|
|
continue;
|
|
rc = security_context_str_to_sid(&selinux_state,
|
|
mount_options[i], &sid,
|
|
GFP_KERNEL);
|
|
if (rc) {
|
|
pr_warn("SELinux: security_context_str_to_sid"
|
|
"(%s) failed for (dev %s, type %s) errno=%d\n",
|
|
mount_options[i], sb->s_id, sb->s_type->name, rc);
|
|
goto out_free_opts;
|
|
}
|
|
rc = -EINVAL;
|
|
switch (flags[i]) {
|
|
case FSCONTEXT_MNT:
|
|
if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
case CONTEXT_MNT:
|
|
if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
case ROOTCONTEXT_MNT: {
|
|
struct inode_security_struct *root_isec;
|
|
root_isec = backing_inode_security(sb->s_root);
|
|
|
|
if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
}
|
|
case DEFCONTEXT_MNT:
|
|
if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
|
|
goto out_bad_option;
|
|
break;
|
|
default:
|
|
goto out_free_opts;
|
|
}
|
|
}
|
|
|
|
rc = 0;
|
|
out_free_opts:
|
|
security_free_mnt_opts(&opts);
|
|
out_free_secdata:
|
|
free_secdata(secdata);
|
|
return rc;
|
|
out_bad_option:
|
|
pr_warn("SELinux: unable to change security options "
|
|
"during remount (dev %s, type=%s)\n", sb->s_id,
|
|
sb->s_type->name);
|
|
goto out_free_opts;
|
|
}
|
|
|
|
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct common_audit_data ad;
|
|
int rc;
|
|
|
|
rc = superblock_doinit(sb, data);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Allow all mounts performed by the kernel */
|
|
if (flags & MS_KERNMOUNT)
|
|
return 0;
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
ad.u.dentry = sb->s_root;
|
|
return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
|
|
}
|
|
|
|
static int selinux_sb_statfs(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct common_audit_data ad;
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
ad.u.dentry = dentry->d_sb->s_root;
|
|
return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
|
|
}
|
|
|
|
static int selinux_mount(const char *dev_name,
|
|
const struct path *path,
|
|
const char *type,
|
|
unsigned long flags,
|
|
void *data)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
if (flags & MS_REMOUNT)
|
|
return superblock_has_perm(cred, path->dentry->d_sb,
|
|
FILESYSTEM__REMOUNT, NULL);
|
|
else
|
|
return path_has_perm(cred, path, FILE__MOUNTON);
|
|
}
|
|
|
|
static int selinux_umount(struct vfsmount *mnt, int flags)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return superblock_has_perm(cred, mnt->mnt_sb,
|
|
FILESYSTEM__UNMOUNT, NULL);
|
|
}
|
|
|
|
/* inode security operations */
|
|
|
|
static int selinux_inode_alloc_security(struct inode *inode)
|
|
{
|
|
return inode_alloc_security(inode);
|
|
}
|
|
|
|
static void selinux_inode_free_security(struct inode *inode)
|
|
{
|
|
inode_free_security(inode);
|
|
}
|
|
|
|
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
|
|
const struct qstr *name, void **ctx,
|
|
u32 *ctxlen)
|
|
{
|
|
u32 newsid;
|
|
int rc;
|
|
|
|
rc = selinux_determine_inode_label(current_security(),
|
|
d_inode(dentry->d_parent), name,
|
|
inode_mode_to_security_class(mode),
|
|
&newsid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
|
|
ctxlen);
|
|
}
|
|
|
|
static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
|
|
struct qstr *name,
|
|
const struct cred *old,
|
|
struct cred *new)
|
|
{
|
|
u32 newsid;
|
|
int rc;
|
|
struct task_security_struct *tsec;
|
|
|
|
rc = selinux_determine_inode_label(old->security,
|
|
d_inode(dentry->d_parent), name,
|
|
inode_mode_to_security_class(mode),
|
|
&newsid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
tsec = new->security;
|
|
tsec->create_sid = newsid;
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
|
|
const struct qstr *qstr,
|
|
const char **name,
|
|
void **value, size_t *len)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct superblock_security_struct *sbsec;
|
|
u32 newsid, clen;
|
|
int rc;
|
|
char *context;
|
|
|
|
sbsec = dir->i_sb->s_security;
|
|
|
|
newsid = tsec->create_sid;
|
|
|
|
rc = selinux_determine_inode_label(current_security(),
|
|
dir, qstr,
|
|
inode_mode_to_security_class(inode->i_mode),
|
|
&newsid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Possibly defer initialization to selinux_complete_init. */
|
|
if (sbsec->flags & SE_SBINITIALIZED) {
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
isec->sid = newsid;
|
|
isec->initialized = LABEL_INITIALIZED;
|
|
}
|
|
|
|
if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (name)
|
|
*name = XATTR_SELINUX_SUFFIX;
|
|
|
|
if (value && len) {
|
|
rc = security_sid_to_context_force(&selinux_state, newsid,
|
|
&context, &clen);
|
|
if (rc)
|
|
return rc;
|
|
*value = context;
|
|
*len = clen;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
|
|
{
|
|
return may_create(dir, dentry, SECCLASS_FILE);
|
|
}
|
|
|
|
static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
|
|
{
|
|
return may_link(dir, old_dentry, MAY_LINK);
|
|
}
|
|
|
|
static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
|
|
{
|
|
return may_link(dir, dentry, MAY_UNLINK);
|
|
}
|
|
|
|
static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
|
|
{
|
|
return may_create(dir, dentry, SECCLASS_LNK_FILE);
|
|
}
|
|
|
|
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
|
|
{
|
|
return may_create(dir, dentry, SECCLASS_DIR);
|
|
}
|
|
|
|
static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
|
|
{
|
|
return may_link(dir, dentry, MAY_RMDIR);
|
|
}
|
|
|
|
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
|
|
{
|
|
return may_create(dir, dentry, inode_mode_to_security_class(mode));
|
|
}
|
|
|
|
static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
|
|
struct inode *new_inode, struct dentry *new_dentry)
|
|
{
|
|
return may_rename(old_inode, old_dentry, new_inode, new_dentry);
|
|
}
|
|
|
|
static int selinux_inode_readlink(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__READ);
|
|
}
|
|
|
|
static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
|
|
bool rcu)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct common_audit_data ad;
|
|
struct inode_security_struct *isec;
|
|
u32 sid;
|
|
|
|
validate_creds(cred);
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
ad.u.dentry = dentry;
|
|
sid = cred_sid(cred);
|
|
isec = inode_security_rcu(inode, rcu);
|
|
if (IS_ERR(isec))
|
|
return PTR_ERR(isec);
|
|
|
|
return avc_has_perm_flags(&selinux_state,
|
|
sid, isec->sid, isec->sclass, FILE__READ, &ad,
|
|
rcu ? MAY_NOT_BLOCK : 0);
|
|
}
|
|
|
|
static noinline int audit_inode_permission(struct inode *inode,
|
|
u32 perms, u32 audited, u32 denied,
|
|
int result,
|
|
unsigned flags)
|
|
{
|
|
struct common_audit_data ad;
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
int rc;
|
|
|
|
ad.type = LSM_AUDIT_DATA_INODE;
|
|
ad.u.inode = inode;
|
|
|
|
rc = slow_avc_audit(&selinux_state,
|
|
current_sid(), isec->sid, isec->sclass, perms,
|
|
audited, denied, result, &ad, flags);
|
|
if (rc)
|
|
return rc;
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_inode_permission(struct inode *inode, int mask)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
u32 perms;
|
|
bool from_access;
|
|
unsigned flags = mask & MAY_NOT_BLOCK;
|
|
struct inode_security_struct *isec;
|
|
u32 sid;
|
|
struct av_decision avd;
|
|
int rc, rc2;
|
|
u32 audited, denied;
|
|
|
|
from_access = mask & MAY_ACCESS;
|
|
mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
|
|
|
|
/* No permission to check. Existence test. */
|
|
if (!mask)
|
|
return 0;
|
|
|
|
validate_creds(cred);
|
|
|
|
if (unlikely(IS_PRIVATE(inode)))
|
|
return 0;
|
|
|
|
perms = file_mask_to_av(inode->i_mode, mask);
|
|
|
|
sid = cred_sid(cred);
|
|
isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
|
|
if (IS_ERR(isec))
|
|
return PTR_ERR(isec);
|
|
|
|
rc = avc_has_perm_noaudit(&selinux_state,
|
|
sid, isec->sid, isec->sclass, perms, 0, &avd);
|
|
audited = avc_audit_required(perms, &avd, rc,
|
|
from_access ? FILE__AUDIT_ACCESS : 0,
|
|
&denied);
|
|
if (likely(!audited))
|
|
return rc;
|
|
|
|
rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
|
|
if (rc2)
|
|
return rc2;
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct inode *inode = d_backing_inode(dentry);
|
|
unsigned int ia_valid = iattr->ia_valid;
|
|
__u32 av = FILE__WRITE;
|
|
|
|
/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
|
|
if (ia_valid & ATTR_FORCE) {
|
|
ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
|
|
ATTR_FORCE);
|
|
if (!ia_valid)
|
|
return 0;
|
|
}
|
|
|
|
if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
|
|
ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
|
|
return dentry_has_perm(cred, dentry, FILE__SETATTR);
|
|
|
|
if (selinux_policycap_openperm() &&
|
|
inode->i_sb->s_magic != SOCKFS_MAGIC &&
|
|
(ia_valid & ATTR_SIZE) &&
|
|
!(ia_valid & ATTR_FILE))
|
|
av |= FILE__OPEN;
|
|
|
|
return dentry_has_perm(cred, dentry, av);
|
|
}
|
|
|
|
static int selinux_inode_getattr(const struct path *path)
|
|
{
|
|
return path_has_perm(current_cred(), path, FILE__GETATTR);
|
|
}
|
|
|
|
static bool has_cap_mac_admin(bool audit)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;
|
|
|
|
if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
|
|
return false;
|
|
if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
|
|
const void *value, size_t size, int flags)
|
|
{
|
|
struct inode *inode = d_backing_inode(dentry);
|
|
struct inode_security_struct *isec;
|
|
struct superblock_security_struct *sbsec;
|
|
struct common_audit_data ad;
|
|
u32 newsid, sid = current_sid();
|
|
int rc = 0;
|
|
|
|
if (strcmp(name, XATTR_NAME_SELINUX)) {
|
|
rc = cap_inode_setxattr(dentry, name, value, size, flags);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Not an attribute we recognize, so just check the
|
|
ordinary setattr permission. */
|
|
return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
|
|
}
|
|
|
|
sbsec = inode->i_sb->s_security;
|
|
if (!(sbsec->flags & SBLABEL_MNT))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (!inode_owner_or_capable(inode))
|
|
return -EPERM;
|
|
|
|
ad.type = LSM_AUDIT_DATA_DENTRY;
|
|
ad.u.dentry = dentry;
|
|
|
|
isec = backing_inode_security(dentry);
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, isec->sid, isec->sclass,
|
|
FILE__RELABELFROM, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = security_context_to_sid(&selinux_state, value, size, &newsid,
|
|
GFP_KERNEL);
|
|
if (rc == -EINVAL) {
|
|
if (!has_cap_mac_admin(true)) {
|
|
struct audit_buffer *ab;
|
|
size_t audit_size;
|
|
|
|
/* We strip a nul only if it is at the end, otherwise the
|
|
* context contains a nul and we should audit that */
|
|
if (value) {
|
|
const char *str = value;
|
|
|
|
if (str[size - 1] == '\0')
|
|
audit_size = size - 1;
|
|
else
|
|
audit_size = size;
|
|
} else {
|
|
audit_size = 0;
|
|
}
|
|
ab = audit_log_start(audit_context(),
|
|
GFP_ATOMIC, AUDIT_SELINUX_ERR);
|
|
audit_log_format(ab, "op=setxattr invalid_context=");
|
|
audit_log_n_untrustedstring(ab, value, audit_size);
|
|
audit_log_end(ab);
|
|
|
|
return rc;
|
|
}
|
|
rc = security_context_to_sid_force(&selinux_state, value,
|
|
size, &newsid);
|
|
}
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, newsid, isec->sclass,
|
|
FILE__RELABELTO, &ad);
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = security_validate_transition(&selinux_state, isec->sid, newsid,
|
|
sid, isec->sclass);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
newsid,
|
|
sbsec->sid,
|
|
SECCLASS_FILESYSTEM,
|
|
FILESYSTEM__ASSOCIATE,
|
|
&ad);
|
|
}
|
|
|
|
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
|
|
const void *value, size_t size,
|
|
int flags)
|
|
{
|
|
struct inode *inode = d_backing_inode(dentry);
|
|
struct inode_security_struct *isec;
|
|
u32 newsid;
|
|
int rc;
|
|
|
|
if (strcmp(name, XATTR_NAME_SELINUX)) {
|
|
/* Not an attribute we recognize, so nothing to do. */
|
|
return;
|
|
}
|
|
|
|
rc = security_context_to_sid_force(&selinux_state, value, size,
|
|
&newsid);
|
|
if (rc) {
|
|
pr_err("SELinux: unable to map context to SID"
|
|
"for (%s, %lu), rc=%d\n",
|
|
inode->i_sb->s_id, inode->i_ino, -rc);
|
|
return;
|
|
}
|
|
|
|
isec = backing_inode_security(dentry);
|
|
spin_lock(&isec->lock);
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
isec->sid = newsid;
|
|
isec->initialized = LABEL_INITIALIZED;
|
|
spin_unlock(&isec->lock);
|
|
|
|
return;
|
|
}
|
|
|
|
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__GETATTR);
|
|
}
|
|
|
|
static int selinux_inode_listxattr(struct dentry *dentry)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return dentry_has_perm(cred, dentry, FILE__GETATTR);
|
|
}
|
|
|
|
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
|
|
{
|
|
if (strcmp(name, XATTR_NAME_SELINUX)) {
|
|
int rc = cap_inode_removexattr(dentry, name);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Not an attribute we recognize, so just check the
|
|
ordinary setattr permission. */
|
|
return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
|
|
}
|
|
|
|
/* No one is allowed to remove a SELinux security label.
|
|
You can change the label, but all data must be labeled. */
|
|
return -EACCES;
|
|
}
|
|
|
|
/*
|
|
* Copy the inode security context value to the user.
|
|
*
|
|
* Permission check is handled by selinux_inode_getxattr hook.
|
|
*/
|
|
static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
|
|
{
|
|
u32 size;
|
|
int error;
|
|
char *context = NULL;
|
|
struct inode_security_struct *isec;
|
|
|
|
if (strcmp(name, XATTR_SELINUX_SUFFIX))
|
|
return -EOPNOTSUPP;
|
|
|
|
/*
|
|
* If the caller has CAP_MAC_ADMIN, then get the raw context
|
|
* value even if it is not defined by current policy; otherwise,
|
|
* use the in-core value under current policy.
|
|
* Use the non-auditing forms of the permission checks since
|
|
* getxattr may be called by unprivileged processes commonly
|
|
* and lack of permission just means that we fall back to the
|
|
* in-core context value, not a denial.
|
|
*/
|
|
isec = inode_security(inode);
|
|
if (has_cap_mac_admin(false))
|
|
error = security_sid_to_context_force(&selinux_state,
|
|
isec->sid, &context,
|
|
&size);
|
|
else
|
|
error = security_sid_to_context(&selinux_state, isec->sid,
|
|
&context, &size);
|
|
if (error)
|
|
return error;
|
|
error = size;
|
|
if (alloc) {
|
|
*buffer = context;
|
|
goto out_nofree;
|
|
}
|
|
kfree(context);
|
|
out_nofree:
|
|
return error;
|
|
}
|
|
|
|
static int selinux_inode_setsecurity(struct inode *inode, const char *name,
|
|
const void *value, size_t size, int flags)
|
|
{
|
|
struct inode_security_struct *isec = inode_security_novalidate(inode);
|
|
u32 newsid;
|
|
int rc;
|
|
|
|
if (strcmp(name, XATTR_SELINUX_SUFFIX))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (!value || !size)
|
|
return -EACCES;
|
|
|
|
rc = security_context_to_sid(&selinux_state, value, size, &newsid,
|
|
GFP_KERNEL);
|
|
if (rc)
|
|
return rc;
|
|
|
|
spin_lock(&isec->lock);
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
isec->sid = newsid;
|
|
isec->initialized = LABEL_INITIALIZED;
|
|
spin_unlock(&isec->lock);
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
|
|
{
|
|
const int len = sizeof(XATTR_NAME_SELINUX);
|
|
if (buffer && len <= buffer_size)
|
|
memcpy(buffer, XATTR_NAME_SELINUX, len);
|
|
return len;
|
|
}
|
|
|
|
static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
|
|
{
|
|
struct inode_security_struct *isec = inode_security_novalidate(inode);
|
|
*secid = isec->sid;
|
|
}
|
|
|
|
static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
|
|
{
|
|
u32 sid;
|
|
struct task_security_struct *tsec;
|
|
struct cred *new_creds = *new;
|
|
|
|
if (new_creds == NULL) {
|
|
new_creds = prepare_creds();
|
|
if (!new_creds)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
tsec = new_creds->security;
|
|
/* Get label from overlay inode and set it in create_sid */
|
|
selinux_inode_getsecid(d_inode(src), &sid);
|
|
tsec->create_sid = sid;
|
|
*new = new_creds;
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_inode_copy_up_xattr(const char *name)
|
|
{
|
|
/* The copy_up hook above sets the initial context on an inode, but we
|
|
* don't then want to overwrite it by blindly copying all the lower
|
|
* xattrs up. Instead, we have to filter out SELinux-related xattrs.
|
|
*/
|
|
if (strcmp(name, XATTR_NAME_SELINUX) == 0)
|
|
return 1; /* Discard */
|
|
/*
|
|
* Any other attribute apart from SELINUX is not claimed, supported
|
|
* by selinux.
|
|
*/
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
/* file security operations */
|
|
|
|
static int selinux_revalidate_file_permission(struct file *file, int mask)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct inode *inode = file_inode(file);
|
|
|
|
/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
|
|
if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
|
|
mask |= MAY_APPEND;
|
|
|
|
return file_has_perm(cred, file,
|
|
file_mask_to_av(inode->i_mode, mask));
|
|
}
|
|
|
|
static int selinux_file_permission(struct file *file, int mask)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct file_security_struct *fsec = file->f_security;
|
|
struct inode_security_struct *isec;
|
|
u32 sid = current_sid();
|
|
|
|
if (!mask)
|
|
/* No permission to check. Existence test. */
|
|
return 0;
|
|
|
|
isec = inode_security(inode);
|
|
if (sid == fsec->sid && fsec->isid == isec->sid &&
|
|
fsec->pseqno == avc_policy_seqno(&selinux_state))
|
|
/* No change since file_open check. */
|
|
return 0;
|
|
|
|
return selinux_revalidate_file_permission(file, mask);
|
|
}
|
|
|
|
static int selinux_file_alloc_security(struct file *file)
|
|
{
|
|
return file_alloc_security(file);
|
|
}
|
|
|
|
static void selinux_file_free_security(struct file *file)
|
|
{
|
|
file_free_security(file);
|
|
}
|
|
|
|
/*
|
|
* Check whether a task has the ioctl permission and cmd
|
|
* operation to an inode.
|
|
*/
|
|
static int ioctl_has_perm(const struct cred *cred, struct file *file,
|
|
u32 requested, u16 cmd)
|
|
{
|
|
struct common_audit_data ad;
|
|
struct file_security_struct *fsec = file->f_security;
|
|
struct inode *inode = file_inode(file);
|
|
struct inode_security_struct *isec;
|
|
struct lsm_ioctlop_audit ioctl;
|
|
u32 ssid = cred_sid(cred);
|
|
int rc;
|
|
u8 driver = cmd >> 8;
|
|
u8 xperm = cmd & 0xff;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IOCTL_OP;
|
|
ad.u.op = &ioctl;
|
|
ad.u.op->cmd = cmd;
|
|
ad.u.op->path = file->f_path;
|
|
|
|
if (ssid != fsec->sid) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
ssid, fsec->sid,
|
|
SECCLASS_FD,
|
|
FD__USE,
|
|
&ad);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
if (unlikely(IS_PRIVATE(inode)))
|
|
return 0;
|
|
|
|
isec = inode_security(inode);
|
|
rc = avc_has_extended_perms(&selinux_state,
|
|
ssid, isec->sid, isec->sclass,
|
|
requested, driver, xperm, &ad);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int error = 0;
|
|
|
|
switch (cmd) {
|
|
case FIONREAD:
|
|
/* fall through */
|
|
case FIBMAP:
|
|
/* fall through */
|
|
case FIGETBSZ:
|
|
/* fall through */
|
|
case FS_IOC_GETFLAGS:
|
|
/* fall through */
|
|
case FS_IOC_GETVERSION:
|
|
error = file_has_perm(cred, file, FILE__GETATTR);
|
|
break;
|
|
|
|
case FS_IOC_SETFLAGS:
|
|
/* fall through */
|
|
case FS_IOC_SETVERSION:
|
|
error = file_has_perm(cred, file, FILE__SETATTR);
|
|
break;
|
|
|
|
/* sys_ioctl() checks */
|
|
case FIONBIO:
|
|
/* fall through */
|
|
case FIOASYNC:
|
|
error = file_has_perm(cred, file, 0);
|
|
break;
|
|
|
|
case KDSKBENT:
|
|
case KDSKBSENT:
|
|
error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
|
|
SECURITY_CAP_AUDIT, true);
|
|
break;
|
|
|
|
/* default case assumes that the command will go
|
|
* to the file's ioctl() function.
|
|
*/
|
|
default:
|
|
error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
static int default_noexec;
|
|
|
|
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
u32 sid = cred_sid(cred);
|
|
int rc = 0;
|
|
|
|
if (default_noexec &&
|
|
(prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
|
|
(!shared && (prot & PROT_WRITE)))) {
|
|
/*
|
|
* We are making executable an anonymous mapping or a
|
|
* private file mapping that will also be writable.
|
|
* This has an additional check.
|
|
*/
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_PROCESS,
|
|
PROCESS__EXECMEM, NULL);
|
|
if (rc)
|
|
goto error;
|
|
}
|
|
|
|
if (file) {
|
|
/* read access is always possible with a mapping */
|
|
u32 av = FILE__READ;
|
|
|
|
/* write access only matters if the mapping is shared */
|
|
if (shared && (prot & PROT_WRITE))
|
|
av |= FILE__WRITE;
|
|
|
|
if (prot & PROT_EXEC)
|
|
av |= FILE__EXECUTE;
|
|
|
|
return file_has_perm(cred, file, av);
|
|
}
|
|
|
|
error:
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_mmap_addr(unsigned long addr)
|
|
{
|
|
int rc = 0;
|
|
|
|
if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
|
|
u32 sid = current_sid();
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_MEMPROTECT,
|
|
MEMPROTECT__MMAP_ZERO, NULL);
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
|
|
unsigned long prot, unsigned long flags)
|
|
{
|
|
struct common_audit_data ad;
|
|
int rc;
|
|
|
|
if (file) {
|
|
ad.type = LSM_AUDIT_DATA_FILE;
|
|
ad.u.file = file;
|
|
rc = inode_has_perm(current_cred(), file_inode(file),
|
|
FILE__MAP, &ad);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
if (selinux_state.checkreqprot)
|
|
prot = reqprot;
|
|
|
|
return file_map_prot_check(file, prot,
|
|
(flags & MAP_TYPE) == MAP_SHARED);
|
|
}
|
|
|
|
static int selinux_file_mprotect(struct vm_area_struct *vma,
|
|
unsigned long reqprot,
|
|
unsigned long prot)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
u32 sid = cred_sid(cred);
|
|
|
|
if (selinux_state.checkreqprot)
|
|
prot = reqprot;
|
|
|
|
if (default_noexec &&
|
|
(prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
|
|
int rc = 0;
|
|
if (vma->vm_start >= vma->vm_mm->start_brk &&
|
|
vma->vm_end <= vma->vm_mm->brk) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_PROCESS,
|
|
PROCESS__EXECHEAP, NULL);
|
|
} else if (!vma->vm_file &&
|
|
((vma->vm_start <= vma->vm_mm->start_stack &&
|
|
vma->vm_end >= vma->vm_mm->start_stack) ||
|
|
vma_is_stack_for_current(vma))) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_PROCESS,
|
|
PROCESS__EXECSTACK, NULL);
|
|
} else if (vma->vm_file && vma->anon_vma) {
|
|
/*
|
|
* We are making executable a file mapping that has
|
|
* had some COW done. Since pages might have been
|
|
* written, check ability to execute the possibly
|
|
* modified content. This typically should only
|
|
* occur for text relocations.
|
|
*/
|
|
rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
|
|
}
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
|
|
}
|
|
|
|
static int selinux_file_lock(struct file *file, unsigned int cmd)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return file_has_perm(cred, file, FILE__LOCK);
|
|
}
|
|
|
|
static int selinux_file_fcntl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
int err = 0;
|
|
|
|
switch (cmd) {
|
|
case F_SETFL:
|
|
if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
|
|
err = file_has_perm(cred, file, FILE__WRITE);
|
|
break;
|
|
}
|
|
/* fall through */
|
|
case F_SETOWN:
|
|
case F_SETSIG:
|
|
case F_GETFL:
|
|
case F_GETOWN:
|
|
case F_GETSIG:
|
|
case F_GETOWNER_UIDS:
|
|
/* Just check FD__USE permission */
|
|
err = file_has_perm(cred, file, 0);
|
|
break;
|
|
case F_GETLK:
|
|
case F_SETLK:
|
|
case F_SETLKW:
|
|
case F_OFD_GETLK:
|
|
case F_OFD_SETLK:
|
|
case F_OFD_SETLKW:
|
|
#if BITS_PER_LONG == 32
|
|
case F_GETLK64:
|
|
case F_SETLK64:
|
|
case F_SETLKW64:
|
|
#endif
|
|
err = file_has_perm(cred, file, FILE__LOCK);
|
|
break;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static void selinux_file_set_fowner(struct file *file)
|
|
{
|
|
struct file_security_struct *fsec;
|
|
|
|
fsec = file->f_security;
|
|
fsec->fown_sid = current_sid();
|
|
}
|
|
|
|
static int selinux_file_send_sigiotask(struct task_struct *tsk,
|
|
struct fown_struct *fown, int signum)
|
|
{
|
|
struct file *file;
|
|
u32 sid = task_sid(tsk);
|
|
u32 perm;
|
|
struct file_security_struct *fsec;
|
|
|
|
/* struct fown_struct is never outside the context of a struct file */
|
|
file = container_of(fown, struct file, f_owner);
|
|
|
|
fsec = file->f_security;
|
|
|
|
if (!signum)
|
|
perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
|
|
else
|
|
perm = signal_to_av(signum);
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
fsec->fown_sid, sid,
|
|
SECCLASS_PROCESS, perm, NULL);
|
|
}
|
|
|
|
static int selinux_file_receive(struct file *file)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
|
|
return file_has_perm(cred, file, file_to_av(file));
|
|
}
|
|
|
|
static int selinux_file_open(struct file *file)
|
|
{
|
|
struct file_security_struct *fsec;
|
|
struct inode_security_struct *isec;
|
|
|
|
fsec = file->f_security;
|
|
isec = inode_security(file_inode(file));
|
|
/*
|
|
* Save inode label and policy sequence number
|
|
* at open-time so that selinux_file_permission
|
|
* can determine whether revalidation is necessary.
|
|
* Task label is already saved in the file security
|
|
* struct as its SID.
|
|
*/
|
|
fsec->isid = isec->sid;
|
|
fsec->pseqno = avc_policy_seqno(&selinux_state);
|
|
/*
|
|
* Since the inode label or policy seqno may have changed
|
|
* between the selinux_inode_permission check and the saving
|
|
* of state above, recheck that access is still permitted.
|
|
* Otherwise, access might never be revalidated against the
|
|
* new inode label or new policy.
|
|
* This check is not redundant - do not remove.
|
|
*/
|
|
return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
|
|
}
|
|
|
|
/* task security operations */
|
|
|
|
static int selinux_task_alloc(struct task_struct *task,
|
|
unsigned long clone_flags)
|
|
{
|
|
u32 sid = current_sid();
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
|
|
}
|
|
|
|
/*
|
|
* allocate the SELinux part of blank credentials
|
|
*/
|
|
static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
|
|
{
|
|
struct task_security_struct *tsec;
|
|
|
|
tsec = kzalloc(sizeof(struct task_security_struct), gfp);
|
|
if (!tsec)
|
|
return -ENOMEM;
|
|
|
|
cred->security = tsec;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* detach and free the LSM part of a set of credentials
|
|
*/
|
|
static void selinux_cred_free(struct cred *cred)
|
|
{
|
|
struct task_security_struct *tsec = cred->security;
|
|
|
|
/*
|
|
* cred->security == NULL if security_cred_alloc_blank() or
|
|
* security_prepare_creds() returned an error.
|
|
*/
|
|
BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
|
|
cred->security = (void *) 0x7UL;
|
|
kfree(tsec);
|
|
}
|
|
|
|
/*
|
|
* prepare a new set of credentials for modification
|
|
*/
|
|
static int selinux_cred_prepare(struct cred *new, const struct cred *old,
|
|
gfp_t gfp)
|
|
{
|
|
const struct task_security_struct *old_tsec;
|
|
struct task_security_struct *tsec;
|
|
|
|
old_tsec = old->security;
|
|
|
|
tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
|
|
if (!tsec)
|
|
return -ENOMEM;
|
|
|
|
new->security = tsec;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* transfer the SELinux data to a blank set of creds
|
|
*/
|
|
static void selinux_cred_transfer(struct cred *new, const struct cred *old)
|
|
{
|
|
const struct task_security_struct *old_tsec = old->security;
|
|
struct task_security_struct *tsec = new->security;
|
|
|
|
*tsec = *old_tsec;
|
|
}
|
|
|
|
static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
|
|
{
|
|
*secid = cred_sid(c);
|
|
}
|
|
|
|
/*
|
|
* set the security data for a kernel service
|
|
* - all the creation contexts are set to unlabelled
|
|
*/
|
|
static int selinux_kernel_act_as(struct cred *new, u32 secid)
|
|
{
|
|
struct task_security_struct *tsec = new->security;
|
|
u32 sid = current_sid();
|
|
int ret;
|
|
|
|
ret = avc_has_perm(&selinux_state,
|
|
sid, secid,
|
|
SECCLASS_KERNEL_SERVICE,
|
|
KERNEL_SERVICE__USE_AS_OVERRIDE,
|
|
NULL);
|
|
if (ret == 0) {
|
|
tsec->sid = secid;
|
|
tsec->create_sid = 0;
|
|
tsec->keycreate_sid = 0;
|
|
tsec->sockcreate_sid = 0;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* set the file creation context in a security record to the same as the
|
|
* objective context of the specified inode
|
|
*/
|
|
static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
|
|
{
|
|
struct inode_security_struct *isec = inode_security(inode);
|
|
struct task_security_struct *tsec = new->security;
|
|
u32 sid = current_sid();
|
|
int ret;
|
|
|
|
ret = avc_has_perm(&selinux_state,
|
|
sid, isec->sid,
|
|
SECCLASS_KERNEL_SERVICE,
|
|
KERNEL_SERVICE__CREATE_FILES_AS,
|
|
NULL);
|
|
|
|
if (ret == 0)
|
|
tsec->create_sid = isec->sid;
|
|
return ret;
|
|
}
|
|
|
|
static int selinux_kernel_module_request(char *kmod_name)
|
|
{
|
|
struct common_audit_data ad;
|
|
|
|
ad.type = LSM_AUDIT_DATA_KMOD;
|
|
ad.u.kmod_name = kmod_name;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
|
|
SYSTEM__MODULE_REQUEST, &ad);
|
|
}
|
|
|
|
static int selinux_kernel_module_from_file(struct file *file)
|
|
{
|
|
struct common_audit_data ad;
|
|
struct inode_security_struct *isec;
|
|
struct file_security_struct *fsec;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
/* init_module */
|
|
if (file == NULL)
|
|
return avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_SYSTEM,
|
|
SYSTEM__MODULE_LOAD, NULL);
|
|
|
|
/* finit_module */
|
|
|
|
ad.type = LSM_AUDIT_DATA_FILE;
|
|
ad.u.file = file;
|
|
|
|
fsec = file->f_security;
|
|
if (sid != fsec->sid) {
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
isec = inode_security(file_inode(file));
|
|
return avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_SYSTEM,
|
|
SYSTEM__MODULE_LOAD, &ad);
|
|
}
|
|
|
|
static int selinux_kernel_read_file(struct file *file,
|
|
enum kernel_read_file_id id)
|
|
{
|
|
int rc = 0;
|
|
|
|
switch (id) {
|
|
case READING_MODULE:
|
|
rc = selinux_kernel_module_from_file(file);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_kernel_load_data(enum kernel_load_data_id id)
|
|
{
|
|
int rc = 0;
|
|
|
|
switch (id) {
|
|
case LOADING_MODULE:
|
|
rc = selinux_kernel_module_from_file(NULL);
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__SETPGID, NULL);
|
|
}
|
|
|
|
static int selinux_task_getpgid(struct task_struct *p)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__GETPGID, NULL);
|
|
}
|
|
|
|
static int selinux_task_getsid(struct task_struct *p)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__GETSESSION, NULL);
|
|
}
|
|
|
|
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
|
|
{
|
|
*secid = task_sid(p);
|
|
}
|
|
|
|
static int selinux_task_setnice(struct task_struct *p, int nice)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__SETSCHED, NULL);
|
|
}
|
|
|
|
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__SETSCHED, NULL);
|
|
}
|
|
|
|
static int selinux_task_getioprio(struct task_struct *p)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__GETSCHED, NULL);
|
|
}
|
|
|
|
static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
|
|
unsigned int flags)
|
|
{
|
|
u32 av = 0;
|
|
|
|
if (!flags)
|
|
return 0;
|
|
if (flags & LSM_PRLIMIT_WRITE)
|
|
av |= PROCESS__SETRLIMIT;
|
|
if (flags & LSM_PRLIMIT_READ)
|
|
av |= PROCESS__GETRLIMIT;
|
|
return avc_has_perm(&selinux_state,
|
|
cred_sid(cred), cred_sid(tcred),
|
|
SECCLASS_PROCESS, av, NULL);
|
|
}
|
|
|
|
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
|
|
struct rlimit *new_rlim)
|
|
{
|
|
struct rlimit *old_rlim = p->signal->rlim + resource;
|
|
|
|
/* Control the ability to change the hard limit (whether
|
|
lowering or raising it), so that the hard limit can
|
|
later be used as a safe reset point for the soft limit
|
|
upon context transitions. See selinux_bprm_committing_creds. */
|
|
if (old_rlim->rlim_max != new_rlim->rlim_max)
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p),
|
|
SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_task_setscheduler(struct task_struct *p)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__SETSCHED, NULL);
|
|
}
|
|
|
|
static int selinux_task_getscheduler(struct task_struct *p)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__GETSCHED, NULL);
|
|
}
|
|
|
|
static int selinux_task_movememory(struct task_struct *p)
|
|
{
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), task_sid(p), SECCLASS_PROCESS,
|
|
PROCESS__SETSCHED, NULL);
|
|
}
|
|
|
|
static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
|
|
int sig, const struct cred *cred)
|
|
{
|
|
u32 secid;
|
|
u32 perm;
|
|
|
|
if (!sig)
|
|
perm = PROCESS__SIGNULL; /* null signal; existence test */
|
|
else
|
|
perm = signal_to_av(sig);
|
|
if (!cred)
|
|
secid = current_sid();
|
|
else
|
|
secid = cred_sid(cred);
|
|
return avc_has_perm(&selinux_state,
|
|
secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
|
|
}
|
|
|
|
static void selinux_task_to_inode(struct task_struct *p,
|
|
struct inode *inode)
|
|
{
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
u32 sid = task_sid(p);
|
|
|
|
spin_lock(&isec->lock);
|
|
isec->sclass = inode_mode_to_security_class(inode->i_mode);
|
|
isec->sid = sid;
|
|
isec->initialized = LABEL_INITIALIZED;
|
|
spin_unlock(&isec->lock);
|
|
}
|
|
|
|
/* Returns error only if unable to parse addresses */
|
|
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
|
|
struct common_audit_data *ad, u8 *proto)
|
|
{
|
|
int offset, ihlen, ret = -EINVAL;
|
|
struct iphdr _iph, *ih;
|
|
|
|
offset = skb_network_offset(skb);
|
|
ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
|
|
if (ih == NULL)
|
|
goto out;
|
|
|
|
ihlen = ih->ihl * 4;
|
|
if (ihlen < sizeof(_iph))
|
|
goto out;
|
|
|
|
ad->u.net->v4info.saddr = ih->saddr;
|
|
ad->u.net->v4info.daddr = ih->daddr;
|
|
ret = 0;
|
|
|
|
if (proto)
|
|
*proto = ih->protocol;
|
|
|
|
switch (ih->protocol) {
|
|
case IPPROTO_TCP: {
|
|
struct tcphdr _tcph, *th;
|
|
|
|
if (ntohs(ih->frag_off) & IP_OFFSET)
|
|
break;
|
|
|
|
offset += ihlen;
|
|
th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
|
|
if (th == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = th->source;
|
|
ad->u.net->dport = th->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_UDP: {
|
|
struct udphdr _udph, *uh;
|
|
|
|
if (ntohs(ih->frag_off) & IP_OFFSET)
|
|
break;
|
|
|
|
offset += ihlen;
|
|
uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
|
|
if (uh == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = uh->source;
|
|
ad->u.net->dport = uh->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_DCCP: {
|
|
struct dccp_hdr _dccph, *dh;
|
|
|
|
if (ntohs(ih->frag_off) & IP_OFFSET)
|
|
break;
|
|
|
|
offset += ihlen;
|
|
dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
|
|
if (dh == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = dh->dccph_sport;
|
|
ad->u.net->dport = dh->dccph_dport;
|
|
break;
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_IP_SCTP)
|
|
case IPPROTO_SCTP: {
|
|
struct sctphdr _sctph, *sh;
|
|
|
|
if (ntohs(ih->frag_off) & IP_OFFSET)
|
|
break;
|
|
|
|
offset += ihlen;
|
|
sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
|
|
if (sh == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = sh->source;
|
|
ad->u.net->dport = sh->dest;
|
|
break;
|
|
}
|
|
#endif
|
|
default:
|
|
break;
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
|
|
/* Returns error only if unable to parse addresses */
|
|
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
|
|
struct common_audit_data *ad, u8 *proto)
|
|
{
|
|
u8 nexthdr;
|
|
int ret = -EINVAL, offset;
|
|
struct ipv6hdr _ipv6h, *ip6;
|
|
__be16 frag_off;
|
|
|
|
offset = skb_network_offset(skb);
|
|
ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
|
|
if (ip6 == NULL)
|
|
goto out;
|
|
|
|
ad->u.net->v6info.saddr = ip6->saddr;
|
|
ad->u.net->v6info.daddr = ip6->daddr;
|
|
ret = 0;
|
|
|
|
nexthdr = ip6->nexthdr;
|
|
offset += sizeof(_ipv6h);
|
|
offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
|
|
if (offset < 0)
|
|
goto out;
|
|
|
|
if (proto)
|
|
*proto = nexthdr;
|
|
|
|
switch (nexthdr) {
|
|
case IPPROTO_TCP: {
|
|
struct tcphdr _tcph, *th;
|
|
|
|
th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
|
|
if (th == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = th->source;
|
|
ad->u.net->dport = th->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_UDP: {
|
|
struct udphdr _udph, *uh;
|
|
|
|
uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
|
|
if (uh == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = uh->source;
|
|
ad->u.net->dport = uh->dest;
|
|
break;
|
|
}
|
|
|
|
case IPPROTO_DCCP: {
|
|
struct dccp_hdr _dccph, *dh;
|
|
|
|
dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
|
|
if (dh == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = dh->dccph_sport;
|
|
ad->u.net->dport = dh->dccph_dport;
|
|
break;
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_IP_SCTP)
|
|
case IPPROTO_SCTP: {
|
|
struct sctphdr _sctph, *sh;
|
|
|
|
sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
|
|
if (sh == NULL)
|
|
break;
|
|
|
|
ad->u.net->sport = sh->source;
|
|
ad->u.net->dport = sh->dest;
|
|
break;
|
|
}
|
|
#endif
|
|
/* includes fragments */
|
|
default:
|
|
break;
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
#endif /* IPV6 */
|
|
|
|
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
|
|
char **_addrp, int src, u8 *proto)
|
|
{
|
|
char *addrp;
|
|
int ret;
|
|
|
|
switch (ad->u.net->family) {
|
|
case PF_INET:
|
|
ret = selinux_parse_skb_ipv4(skb, ad, proto);
|
|
if (ret)
|
|
goto parse_error;
|
|
addrp = (char *)(src ? &ad->u.net->v4info.saddr :
|
|
&ad->u.net->v4info.daddr);
|
|
goto okay;
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
case PF_INET6:
|
|
ret = selinux_parse_skb_ipv6(skb, ad, proto);
|
|
if (ret)
|
|
goto parse_error;
|
|
addrp = (char *)(src ? &ad->u.net->v6info.saddr :
|
|
&ad->u.net->v6info.daddr);
|
|
goto okay;
|
|
#endif /* IPV6 */
|
|
default:
|
|
addrp = NULL;
|
|
goto okay;
|
|
}
|
|
|
|
parse_error:
|
|
pr_warn(
|
|
"SELinux: failure in selinux_parse_skb(),"
|
|
" unable to parse packet\n");
|
|
return ret;
|
|
|
|
okay:
|
|
if (_addrp)
|
|
*_addrp = addrp;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* selinux_skb_peerlbl_sid - Determine the peer label of a packet
|
|
* @skb: the packet
|
|
* @family: protocol family
|
|
* @sid: the packet's peer label SID
|
|
*
|
|
* Description:
|
|
* Check the various different forms of network peer labeling and determine
|
|
* the peer label/SID for the packet; most of the magic actually occurs in
|
|
* the security server function security_net_peersid_cmp(). The function
|
|
* returns zero if the value in @sid is valid (although it may be SECSID_NULL)
|
|
* or -EACCES if @sid is invalid due to inconsistencies with the different
|
|
* peer labels.
|
|
*
|
|
*/
|
|
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
|
|
{
|
|
int err;
|
|
u32 xfrm_sid;
|
|
u32 nlbl_sid;
|
|
u32 nlbl_type;
|
|
|
|
err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
|
|
if (unlikely(err))
|
|
return -EACCES;
|
|
err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
|
|
if (unlikely(err))
|
|
return -EACCES;
|
|
|
|
err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
|
|
nlbl_type, xfrm_sid, sid);
|
|
if (unlikely(err)) {
|
|
pr_warn(
|
|
"SELinux: failure in selinux_skb_peerlbl_sid(),"
|
|
" unable to determine packet's peer label\n");
|
|
return -EACCES;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* selinux_conn_sid - Determine the child socket label for a connection
|
|
* @sk_sid: the parent socket's SID
|
|
* @skb_sid: the packet's SID
|
|
* @conn_sid: the resulting connection SID
|
|
*
|
|
* If @skb_sid is valid then the user:role:type information from @sk_sid is
|
|
* combined with the MLS information from @skb_sid in order to create
|
|
* @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
|
|
* of @sk_sid. Returns zero on success, negative values on failure.
|
|
*
|
|
*/
|
|
static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
|
|
{
|
|
int err = 0;
|
|
|
|
if (skb_sid != SECSID_NULL)
|
|
err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
|
|
conn_sid);
|
|
else
|
|
*conn_sid = sk_sid;
|
|
|
|
return err;
|
|
}
|
|
|
|
/* socket security operations */
|
|
|
|
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
|
|
u16 secclass, u32 *socksid)
|
|
{
|
|
if (tsec->sockcreate_sid > SECSID_NULL) {
|
|
*socksid = tsec->sockcreate_sid;
|
|
return 0;
|
|
}
|
|
|
|
return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
|
|
secclass, NULL, socksid);
|
|
}
|
|
|
|
static int sock_has_perm(struct sock *sk, u32 perms)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
|
|
if (sksec->sid == SECINITSID_KERNEL)
|
|
return 0;
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->sk = sk;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), sksec->sid, sksec->sclass, perms,
|
|
&ad);
|
|
}
|
|
|
|
static int selinux_socket_create(int family, int type,
|
|
int protocol, int kern)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
u32 newsid;
|
|
u16 secclass;
|
|
int rc;
|
|
|
|
if (kern)
|
|
return 0;
|
|
|
|
secclass = socket_type_to_security_class(family, type, protocol);
|
|
rc = socket_sockcreate_sid(tsec, secclass, &newsid);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
|
|
}
|
|
|
|
static int selinux_socket_post_create(struct socket *sock, int family,
|
|
int type, int protocol, int kern)
|
|
{
|
|
const struct task_security_struct *tsec = current_security();
|
|
struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
|
|
struct sk_security_struct *sksec;
|
|
u16 sclass = socket_type_to_security_class(family, type, protocol);
|
|
u32 sid = SECINITSID_KERNEL;
|
|
int err = 0;
|
|
|
|
if (!kern) {
|
|
err = socket_sockcreate_sid(tsec, sclass, &sid);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
isec->sclass = sclass;
|
|
isec->sid = sid;
|
|
isec->initialized = LABEL_INITIALIZED;
|
|
|
|
if (sock->sk) {
|
|
sksec = sock->sk->sk_security;
|
|
sksec->sclass = sclass;
|
|
sksec->sid = sid;
|
|
/* Allows detection of the first association on this socket */
|
|
if (sksec->sclass == SECCLASS_SCTP_SOCKET)
|
|
sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
|
|
|
|
err = selinux_netlbl_socket_post_create(sock->sk, family);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_socketpair(struct socket *socka,
|
|
struct socket *sockb)
|
|
{
|
|
struct sk_security_struct *sksec_a = socka->sk->sk_security;
|
|
struct sk_security_struct *sksec_b = sockb->sk->sk_security;
|
|
|
|
sksec_a->peer_sid = sksec_b->sid;
|
|
sksec_b->peer_sid = sksec_a->sid;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Range of port numbers used to automatically bind.
|
|
Need to determine whether we should perform a name_bind
|
|
permission check between the socket and the port number. */
|
|
|
|
static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
|
|
{
|
|
struct sock *sk = sock->sk;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
u16 family;
|
|
int err;
|
|
|
|
err = sock_has_perm(sk, SOCKET__BIND);
|
|
if (err)
|
|
goto out;
|
|
|
|
/* If PF_INET or PF_INET6, check name_bind permission for the port. */
|
|
family = sk->sk_family;
|
|
if (family == PF_INET || family == PF_INET6) {
|
|
char *addrp;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
struct sockaddr_in *addr4 = NULL;
|
|
struct sockaddr_in6 *addr6 = NULL;
|
|
u16 family_sa = address->sa_family;
|
|
unsigned short snum;
|
|
u32 sid, node_perm;
|
|
|
|
/*
|
|
* sctp_bindx(3) calls via selinux_sctp_bind_connect()
|
|
* that validates multiple binding addresses. Because of this
|
|
* need to check address->sa_family as it is possible to have
|
|
* sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
|
|
*/
|
|
switch (family_sa) {
|
|
case AF_UNSPEC:
|
|
case AF_INET:
|
|
if (addrlen < sizeof(struct sockaddr_in))
|
|
return -EINVAL;
|
|
addr4 = (struct sockaddr_in *)address;
|
|
if (family_sa == AF_UNSPEC) {
|
|
/* see __inet_bind(), we only want to allow
|
|
* AF_UNSPEC if the address is INADDR_ANY
|
|
*/
|
|
if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
|
|
goto err_af;
|
|
family_sa = AF_INET;
|
|
}
|
|
snum = ntohs(addr4->sin_port);
|
|
addrp = (char *)&addr4->sin_addr.s_addr;
|
|
break;
|
|
case AF_INET6:
|
|
if (addrlen < SIN6_LEN_RFC2133)
|
|
return -EINVAL;
|
|
addr6 = (struct sockaddr_in6 *)address;
|
|
snum = ntohs(addr6->sin6_port);
|
|
addrp = (char *)&addr6->sin6_addr.s6_addr;
|
|
break;
|
|
default:
|
|
goto err_af;
|
|
}
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->sport = htons(snum);
|
|
ad.u.net->family = family_sa;
|
|
|
|
if (snum) {
|
|
int low, high;
|
|
|
|
inet_get_local_port_range(sock_net(sk), &low, &high);
|
|
|
|
if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
|
|
snum > high) {
|
|
err = sel_netport_sid(sk->sk_protocol,
|
|
snum, &sid);
|
|
if (err)
|
|
goto out;
|
|
err = avc_has_perm(&selinux_state,
|
|
sksec->sid, sid,
|
|
sksec->sclass,
|
|
SOCKET__NAME_BIND, &ad);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
switch (sksec->sclass) {
|
|
case SECCLASS_TCP_SOCKET:
|
|
node_perm = TCP_SOCKET__NODE_BIND;
|
|
break;
|
|
|
|
case SECCLASS_UDP_SOCKET:
|
|
node_perm = UDP_SOCKET__NODE_BIND;
|
|
break;
|
|
|
|
case SECCLASS_DCCP_SOCKET:
|
|
node_perm = DCCP_SOCKET__NODE_BIND;
|
|
break;
|
|
|
|
case SECCLASS_SCTP_SOCKET:
|
|
node_perm = SCTP_SOCKET__NODE_BIND;
|
|
break;
|
|
|
|
default:
|
|
node_perm = RAWIP_SOCKET__NODE_BIND;
|
|
break;
|
|
}
|
|
|
|
err = sel_netnode_sid(addrp, family_sa, &sid);
|
|
if (err)
|
|
goto out;
|
|
|
|
if (family_sa == AF_INET)
|
|
ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
|
|
else
|
|
ad.u.net->v6info.saddr = addr6->sin6_addr;
|
|
|
|
err = avc_has_perm(&selinux_state,
|
|
sksec->sid, sid,
|
|
sksec->sclass, node_perm, &ad);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
out:
|
|
return err;
|
|
err_af:
|
|
/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
|
|
if (sksec->sclass == SECCLASS_SCTP_SOCKET)
|
|
return -EINVAL;
|
|
return -EAFNOSUPPORT;
|
|
}
|
|
|
|
/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
|
|
* and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.rst
|
|
*/
|
|
static int selinux_socket_connect_helper(struct socket *sock,
|
|
struct sockaddr *address, int addrlen)
|
|
{
|
|
struct sock *sk = sock->sk;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
int err;
|
|
|
|
err = sock_has_perm(sk, SOCKET__CONNECT);
|
|
if (err)
|
|
return err;
|
|
|
|
/*
|
|
* If a TCP, DCCP or SCTP socket, check name_connect permission
|
|
* for the port.
|
|
*/
|
|
if (sksec->sclass == SECCLASS_TCP_SOCKET ||
|
|
sksec->sclass == SECCLASS_DCCP_SOCKET ||
|
|
sksec->sclass == SECCLASS_SCTP_SOCKET) {
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
struct sockaddr_in *addr4 = NULL;
|
|
struct sockaddr_in6 *addr6 = NULL;
|
|
unsigned short snum;
|
|
u32 sid, perm;
|
|
|
|
/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
|
|
* that validates multiple connect addresses. Because of this
|
|
* need to check address->sa_family as it is possible to have
|
|
* sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
|
|
*/
|
|
switch (address->sa_family) {
|
|
case AF_INET:
|
|
addr4 = (struct sockaddr_in *)address;
|
|
if (addrlen < sizeof(struct sockaddr_in))
|
|
return -EINVAL;
|
|
snum = ntohs(addr4->sin_port);
|
|
break;
|
|
case AF_INET6:
|
|
addr6 = (struct sockaddr_in6 *)address;
|
|
if (addrlen < SIN6_LEN_RFC2133)
|
|
return -EINVAL;
|
|
snum = ntohs(addr6->sin6_port);
|
|
break;
|
|
default:
|
|
/* Note that SCTP services expect -EINVAL, whereas
|
|
* others expect -EAFNOSUPPORT.
|
|
*/
|
|
if (sksec->sclass == SECCLASS_SCTP_SOCKET)
|
|
return -EINVAL;
|
|
else
|
|
return -EAFNOSUPPORT;
|
|
}
|
|
|
|
err = sel_netport_sid(sk->sk_protocol, snum, &sid);
|
|
if (err)
|
|
return err;
|
|
|
|
switch (sksec->sclass) {
|
|
case SECCLASS_TCP_SOCKET:
|
|
perm = TCP_SOCKET__NAME_CONNECT;
|
|
break;
|
|
case SECCLASS_DCCP_SOCKET:
|
|
perm = DCCP_SOCKET__NAME_CONNECT;
|
|
break;
|
|
case SECCLASS_SCTP_SOCKET:
|
|
perm = SCTP_SOCKET__NAME_CONNECT;
|
|
break;
|
|
}
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->dport = htons(snum);
|
|
ad.u.net->family = address->sa_family;
|
|
err = avc_has_perm(&selinux_state,
|
|
sksec->sid, sid, sksec->sclass, perm, &ad);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Supports connect(2), see comments in selinux_socket_connect_helper() */
|
|
static int selinux_socket_connect(struct socket *sock,
|
|
struct sockaddr *address, int addrlen)
|
|
{
|
|
int err;
|
|
struct sock *sk = sock->sk;
|
|
|
|
err = selinux_socket_connect_helper(sock, address, addrlen);
|
|
if (err)
|
|
return err;
|
|
|
|
return selinux_netlbl_socket_connect(sk, address);
|
|
}
|
|
|
|
static int selinux_socket_listen(struct socket *sock, int backlog)
|
|
{
|
|
return sock_has_perm(sock->sk, SOCKET__LISTEN);
|
|
}
|
|
|
|
static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
|
|
{
|
|
int err;
|
|
struct inode_security_struct *isec;
|
|
struct inode_security_struct *newisec;
|
|
u16 sclass;
|
|
u32 sid;
|
|
|
|
err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
|
|
if (err)
|
|
return err;
|
|
|
|
isec = inode_security_novalidate(SOCK_INODE(sock));
|
|
spin_lock(&isec->lock);
|
|
sclass = isec->sclass;
|
|
sid = isec->sid;
|
|
spin_unlock(&isec->lock);
|
|
|
|
newisec = inode_security_novalidate(SOCK_INODE(newsock));
|
|
newisec->sclass = sclass;
|
|
newisec->sid = sid;
|
|
newisec->initialized = LABEL_INITIALIZED;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
|
|
int size)
|
|
{
|
|
return sock_has_perm(sock->sk, SOCKET__WRITE);
|
|
}
|
|
|
|
static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
|
|
int size, int flags)
|
|
{
|
|
return sock_has_perm(sock->sk, SOCKET__READ);
|
|
}
|
|
|
|
static int selinux_socket_getsockname(struct socket *sock)
|
|
{
|
|
return sock_has_perm(sock->sk, SOCKET__GETATTR);
|
|
}
|
|
|
|
static int selinux_socket_getpeername(struct socket *sock)
|
|
{
|
|
return sock_has_perm(sock->sk, SOCKET__GETATTR);
|
|
}
|
|
|
|
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
|
|
{
|
|
int err;
|
|
|
|
err = sock_has_perm(sock->sk, SOCKET__SETOPT);
|
|
if (err)
|
|
return err;
|
|
|
|
return selinux_netlbl_socket_setsockopt(sock, level, optname);
|
|
}
|
|
|
|
static int selinux_socket_getsockopt(struct socket *sock, int level,
|
|
int optname)
|
|
{
|
|
return sock_has_perm(sock->sk, SOCKET__GETOPT);
|
|
}
|
|
|
|
static int selinux_socket_shutdown(struct socket *sock, int how)
|
|
{
|
|
return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
|
|
}
|
|
|
|
static int selinux_socket_unix_stream_connect(struct sock *sock,
|
|
struct sock *other,
|
|
struct sock *newsk)
|
|
{
|
|
struct sk_security_struct *sksec_sock = sock->sk_security;
|
|
struct sk_security_struct *sksec_other = other->sk_security;
|
|
struct sk_security_struct *sksec_new = newsk->sk_security;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
int err;
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->sk = other;
|
|
|
|
err = avc_has_perm(&selinux_state,
|
|
sksec_sock->sid, sksec_other->sid,
|
|
sksec_other->sclass,
|
|
UNIX_STREAM_SOCKET__CONNECTTO, &ad);
|
|
if (err)
|
|
return err;
|
|
|
|
/* server child socket */
|
|
sksec_new->peer_sid = sksec_sock->sid;
|
|
err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
|
|
sksec_sock->sid, &sksec_new->sid);
|
|
if (err)
|
|
return err;
|
|
|
|
/* connecting socket */
|
|
sksec_sock->peer_sid = sksec_new->sid;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_socket_unix_may_send(struct socket *sock,
|
|
struct socket *other)
|
|
{
|
|
struct sk_security_struct *ssec = sock->sk->sk_security;
|
|
struct sk_security_struct *osec = other->sk->sk_security;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->sk = other->sk;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
|
|
&ad);
|
|
}
|
|
|
|
static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
|
|
char *addrp, u16 family, u32 peer_sid,
|
|
struct common_audit_data *ad)
|
|
{
|
|
int err;
|
|
u32 if_sid;
|
|
u32 node_sid;
|
|
|
|
err = sel_netif_sid(ns, ifindex, &if_sid);
|
|
if (err)
|
|
return err;
|
|
err = avc_has_perm(&selinux_state,
|
|
peer_sid, if_sid,
|
|
SECCLASS_NETIF, NETIF__INGRESS, ad);
|
|
if (err)
|
|
return err;
|
|
|
|
err = sel_netnode_sid(addrp, family, &node_sid);
|
|
if (err)
|
|
return err;
|
|
return avc_has_perm(&selinux_state,
|
|
peer_sid, node_sid,
|
|
SECCLASS_NODE, NODE__RECVFROM, ad);
|
|
}
|
|
|
|
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
|
|
u16 family)
|
|
{
|
|
int err = 0;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
u32 sk_sid = sksec->sid;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
char *addrp;
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->netif = skb->skb_iif;
|
|
ad.u.net->family = family;
|
|
err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
|
|
if (err)
|
|
return err;
|
|
|
|
if (selinux_secmark_enabled()) {
|
|
err = avc_has_perm(&selinux_state,
|
|
sk_sid, skb->secmark, SECCLASS_PACKET,
|
|
PACKET__RECV, &ad);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
|
|
if (err)
|
|
return err;
|
|
err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
int err;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
u16 family = sk->sk_family;
|
|
u32 sk_sid = sksec->sid;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
char *addrp;
|
|
u8 secmark_active;
|
|
u8 peerlbl_active;
|
|
|
|
if (family != PF_INET && family != PF_INET6)
|
|
return 0;
|
|
|
|
/* Handle mapped IPv4 packets arriving via IPv6 sockets */
|
|
if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
|
|
family = PF_INET;
|
|
|
|
/* If any sort of compatibility mode is enabled then handoff processing
|
|
* to the selinux_sock_rcv_skb_compat() function to deal with the
|
|
* special handling. We do this in an attempt to keep this function
|
|
* as fast and as clean as possible. */
|
|
if (!selinux_policycap_netpeer())
|
|
return selinux_sock_rcv_skb_compat(sk, skb, family);
|
|
|
|
secmark_active = selinux_secmark_enabled();
|
|
peerlbl_active = selinux_peerlbl_enabled();
|
|
if (!secmark_active && !peerlbl_active)
|
|
return 0;
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->netif = skb->skb_iif;
|
|
ad.u.net->family = family;
|
|
err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
|
|
if (err)
|
|
return err;
|
|
|
|
if (peerlbl_active) {
|
|
u32 peer_sid;
|
|
|
|
err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
|
|
if (err)
|
|
return err;
|
|
err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
|
|
addrp, family, peer_sid, &ad);
|
|
if (err) {
|
|
selinux_netlbl_err(skb, family, err, 0);
|
|
return err;
|
|
}
|
|
err = avc_has_perm(&selinux_state,
|
|
sk_sid, peer_sid, SECCLASS_PEER,
|
|
PEER__RECV, &ad);
|
|
if (err) {
|
|
selinux_netlbl_err(skb, family, err, 0);
|
|
return err;
|
|
}
|
|
}
|
|
|
|
if (secmark_active) {
|
|
err = avc_has_perm(&selinux_state,
|
|
sk_sid, skb->secmark, SECCLASS_PACKET,
|
|
PACKET__RECV, &ad);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
|
|
int __user *optlen, unsigned len)
|
|
{
|
|
int err = 0;
|
|
char *scontext;
|
|
u32 scontext_len;
|
|
struct sk_security_struct *sksec = sock->sk->sk_security;
|
|
u32 peer_sid = SECSID_NULL;
|
|
|
|
if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
|
|
sksec->sclass == SECCLASS_TCP_SOCKET ||
|
|
sksec->sclass == SECCLASS_SCTP_SOCKET)
|
|
peer_sid = sksec->peer_sid;
|
|
if (peer_sid == SECSID_NULL)
|
|
return -ENOPROTOOPT;
|
|
|
|
err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
|
|
&scontext_len);
|
|
if (err)
|
|
return err;
|
|
|
|
if (scontext_len > len) {
|
|
err = -ERANGE;
|
|
goto out_len;
|
|
}
|
|
|
|
if (copy_to_user(optval, scontext, scontext_len))
|
|
err = -EFAULT;
|
|
|
|
out_len:
|
|
if (put_user(scontext_len, optlen))
|
|
err = -EFAULT;
|
|
kfree(scontext);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
|
|
{
|
|
u32 peer_secid = SECSID_NULL;
|
|
u16 family;
|
|
struct inode_security_struct *isec;
|
|
|
|
if (skb && skb->protocol == htons(ETH_P_IP))
|
|
family = PF_INET;
|
|
else if (skb && skb->protocol == htons(ETH_P_IPV6))
|
|
family = PF_INET6;
|
|
else if (sock)
|
|
family = sock->sk->sk_family;
|
|
else
|
|
goto out;
|
|
|
|
if (sock && family == PF_UNIX) {
|
|
isec = inode_security_novalidate(SOCK_INODE(sock));
|
|
peer_secid = isec->sid;
|
|
} else if (skb)
|
|
selinux_skb_peerlbl_sid(skb, family, &peer_secid);
|
|
|
|
out:
|
|
*secid = peer_secid;
|
|
if (peer_secid == SECSID_NULL)
|
|
return -EINVAL;
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
|
|
{
|
|
struct sk_security_struct *sksec;
|
|
|
|
sksec = kzalloc(sizeof(*sksec), priority);
|
|
if (!sksec)
|
|
return -ENOMEM;
|
|
|
|
sksec->peer_sid = SECINITSID_UNLABELED;
|
|
sksec->sid = SECINITSID_UNLABELED;
|
|
sksec->sclass = SECCLASS_SOCKET;
|
|
selinux_netlbl_sk_security_reset(sksec);
|
|
sk->sk_security = sksec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_sk_free_security(struct sock *sk)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
sk->sk_security = NULL;
|
|
selinux_netlbl_sk_security_free(sksec);
|
|
kfree(sksec);
|
|
}
|
|
|
|
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
struct sk_security_struct *newsksec = newsk->sk_security;
|
|
|
|
newsksec->sid = sksec->sid;
|
|
newsksec->peer_sid = sksec->peer_sid;
|
|
newsksec->sclass = sksec->sclass;
|
|
|
|
selinux_netlbl_sk_security_reset(newsksec);
|
|
}
|
|
|
|
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
|
|
{
|
|
if (!sk)
|
|
*secid = SECINITSID_ANY_SOCKET;
|
|
else {
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
*secid = sksec->sid;
|
|
}
|
|
}
|
|
|
|
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
|
|
{
|
|
struct inode_security_struct *isec =
|
|
inode_security_novalidate(SOCK_INODE(parent));
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
|
|
sk->sk_family == PF_UNIX)
|
|
isec->sid = sksec->sid;
|
|
sksec->sclass = isec->sclass;
|
|
}
|
|
|
|
/* Called whenever SCTP receives an INIT chunk. This happens when an incoming
|
|
* connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
|
|
* already present).
|
|
*/
|
|
static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct sk_security_struct *sksec = ep->base.sk->sk_security;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
u8 peerlbl_active;
|
|
u32 peer_sid = SECINITSID_UNLABELED;
|
|
u32 conn_sid;
|
|
int err = 0;
|
|
|
|
if (!selinux_policycap_extsockclass())
|
|
return 0;
|
|
|
|
peerlbl_active = selinux_peerlbl_enabled();
|
|
|
|
if (peerlbl_active) {
|
|
/* This will return peer_sid = SECSID_NULL if there are
|
|
* no peer labels, see security_net_peersid_resolve().
|
|
*/
|
|
err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
|
|
&peer_sid);
|
|
if (err)
|
|
return err;
|
|
|
|
if (peer_sid == SECSID_NULL)
|
|
peer_sid = SECINITSID_UNLABELED;
|
|
}
|
|
|
|
if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
|
|
sksec->sctp_assoc_state = SCTP_ASSOC_SET;
|
|
|
|
/* Here as first association on socket. As the peer SID
|
|
* was allowed by peer recv (and the netif/node checks),
|
|
* then it is approved by policy and used as the primary
|
|
* peer SID for getpeercon(3).
|
|
*/
|
|
sksec->peer_sid = peer_sid;
|
|
} else if (sksec->peer_sid != peer_sid) {
|
|
/* Other association peer SIDs are checked to enforce
|
|
* consistency among the peer SIDs.
|
|
*/
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->sk = ep->base.sk;
|
|
err = avc_has_perm(&selinux_state,
|
|
sksec->peer_sid, peer_sid, sksec->sclass,
|
|
SCTP_SOCKET__ASSOCIATION, &ad);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
/* Compute the MLS component for the connection and store
|
|
* the information in ep. This will be used by SCTP TCP type
|
|
* sockets and peeled off connections as they cause a new
|
|
* socket to be generated. selinux_sctp_sk_clone() will then
|
|
* plug this into the new socket.
|
|
*/
|
|
err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
|
|
if (err)
|
|
return err;
|
|
|
|
ep->secid = conn_sid;
|
|
ep->peer_secid = peer_sid;
|
|
|
|
/* Set any NetLabel labels including CIPSO/CALIPSO options. */
|
|
return selinux_netlbl_sctp_assoc_request(ep, skb);
|
|
}
|
|
|
|
/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
|
|
* based on their @optname.
|
|
*/
|
|
static int selinux_sctp_bind_connect(struct sock *sk, int optname,
|
|
struct sockaddr *address,
|
|
int addrlen)
|
|
{
|
|
int len, err = 0, walk_size = 0;
|
|
void *addr_buf;
|
|
struct sockaddr *addr;
|
|
struct socket *sock;
|
|
|
|
if (!selinux_policycap_extsockclass())
|
|
return 0;
|
|
|
|
/* Process one or more addresses that may be IPv4 or IPv6 */
|
|
sock = sk->sk_socket;
|
|
addr_buf = address;
|
|
|
|
while (walk_size < addrlen) {
|
|
addr = addr_buf;
|
|
switch (addr->sa_family) {
|
|
case AF_UNSPEC:
|
|
case AF_INET:
|
|
len = sizeof(struct sockaddr_in);
|
|
break;
|
|
case AF_INET6:
|
|
len = sizeof(struct sockaddr_in6);
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
err = -EINVAL;
|
|
switch (optname) {
|
|
/* Bind checks */
|
|
case SCTP_PRIMARY_ADDR:
|
|
case SCTP_SET_PEER_PRIMARY_ADDR:
|
|
case SCTP_SOCKOPT_BINDX_ADD:
|
|
err = selinux_socket_bind(sock, addr, len);
|
|
break;
|
|
/* Connect checks */
|
|
case SCTP_SOCKOPT_CONNECTX:
|
|
case SCTP_PARAM_SET_PRIMARY:
|
|
case SCTP_PARAM_ADD_IP:
|
|
case SCTP_SENDMSG_CONNECT:
|
|
err = selinux_socket_connect_helper(sock, addr, len);
|
|
if (err)
|
|
return err;
|
|
|
|
/* As selinux_sctp_bind_connect() is called by the
|
|
* SCTP protocol layer, the socket is already locked,
|
|
* therefore selinux_netlbl_socket_connect_locked() is
|
|
* is called here. The situations handled are:
|
|
* sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
|
|
* whenever a new IP address is added or when a new
|
|
* primary address is selected.
|
|
* Note that an SCTP connect(2) call happens before
|
|
* the SCTP protocol layer and is handled via
|
|
* selinux_socket_connect().
|
|
*/
|
|
err = selinux_netlbl_socket_connect_locked(sk, addr);
|
|
break;
|
|
}
|
|
|
|
if (err)
|
|
return err;
|
|
|
|
addr_buf += len;
|
|
walk_size += len;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
|
|
static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
|
|
struct sock *newsk)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
struct sk_security_struct *newsksec = newsk->sk_security;
|
|
|
|
/* If policy does not support SECCLASS_SCTP_SOCKET then call
|
|
* the non-sctp clone version.
|
|
*/
|
|
if (!selinux_policycap_extsockclass())
|
|
return selinux_sk_clone_security(sk, newsk);
|
|
|
|
newsksec->sid = ep->secid;
|
|
newsksec->peer_sid = ep->peer_secid;
|
|
newsksec->sclass = sksec->sclass;
|
|
selinux_netlbl_sctp_sk_clone(sk, newsk);
|
|
}
|
|
|
|
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
|
|
struct request_sock *req)
|
|
{
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
int err;
|
|
u16 family = req->rsk_ops->family;
|
|
u32 connsid;
|
|
u32 peersid;
|
|
|
|
err = selinux_skb_peerlbl_sid(skb, family, &peersid);
|
|
if (err)
|
|
return err;
|
|
err = selinux_conn_sid(sksec->sid, peersid, &connsid);
|
|
if (err)
|
|
return err;
|
|
req->secid = connsid;
|
|
req->peer_secid = peersid;
|
|
|
|
return selinux_netlbl_inet_conn_request(req, family);
|
|
}
|
|
|
|
static void selinux_inet_csk_clone(struct sock *newsk,
|
|
const struct request_sock *req)
|
|
{
|
|
struct sk_security_struct *newsksec = newsk->sk_security;
|
|
|
|
newsksec->sid = req->secid;
|
|
newsksec->peer_sid = req->peer_secid;
|
|
/* NOTE: Ideally, we should also get the isec->sid for the
|
|
new socket in sync, but we don't have the isec available yet.
|
|
So we will wait until sock_graft to do it, by which
|
|
time it will have been created and available. */
|
|
|
|
/* We don't need to take any sort of lock here as we are the only
|
|
* thread with access to newsksec */
|
|
selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
|
|
}
|
|
|
|
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
u16 family = sk->sk_family;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
/* handle mapped IPv4 packets arriving via IPv6 sockets */
|
|
if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
|
|
family = PF_INET;
|
|
|
|
selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
|
|
}
|
|
|
|
static int selinux_secmark_relabel_packet(u32 sid)
|
|
{
|
|
const struct task_security_struct *__tsec;
|
|
u32 tsid;
|
|
|
|
__tsec = current_security();
|
|
tsid = __tsec->sid;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
|
|
NULL);
|
|
}
|
|
|
|
static void selinux_secmark_refcount_inc(void)
|
|
{
|
|
atomic_inc(&selinux_secmark_refcount);
|
|
}
|
|
|
|
static void selinux_secmark_refcount_dec(void)
|
|
{
|
|
atomic_dec(&selinux_secmark_refcount);
|
|
}
|
|
|
|
static void selinux_req_classify_flow(const struct request_sock *req,
|
|
struct flowi *fl)
|
|
{
|
|
fl->flowi_secid = req->secid;
|
|
}
|
|
|
|
static int selinux_tun_dev_alloc_security(void **security)
|
|
{
|
|
struct tun_security_struct *tunsec;
|
|
|
|
tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
|
|
if (!tunsec)
|
|
return -ENOMEM;
|
|
tunsec->sid = current_sid();
|
|
|
|
*security = tunsec;
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_tun_dev_free_security(void *security)
|
|
{
|
|
kfree(security);
|
|
}
|
|
|
|
static int selinux_tun_dev_create(void)
|
|
{
|
|
u32 sid = current_sid();
|
|
|
|
/* we aren't taking into account the "sockcreate" SID since the socket
|
|
* that is being created here is not a socket in the traditional sense,
|
|
* instead it is a private sock, accessible only to the kernel, and
|
|
* representing a wide range of network traffic spanning multiple
|
|
* connections unlike traditional sockets - check the TUN driver to
|
|
* get a better understanding of why this socket is special */
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
|
|
NULL);
|
|
}
|
|
|
|
static int selinux_tun_dev_attach_queue(void *security)
|
|
{
|
|
struct tun_security_struct *tunsec = security;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
|
|
TUN_SOCKET__ATTACH_QUEUE, NULL);
|
|
}
|
|
|
|
static int selinux_tun_dev_attach(struct sock *sk, void *security)
|
|
{
|
|
struct tun_security_struct *tunsec = security;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
/* we don't currently perform any NetLabel based labeling here and it
|
|
* isn't clear that we would want to do so anyway; while we could apply
|
|
* labeling without the support of the TUN user the resulting labeled
|
|
* traffic from the other end of the connection would almost certainly
|
|
* cause confusion to the TUN user that had no idea network labeling
|
|
* protocols were being used */
|
|
|
|
sksec->sid = tunsec->sid;
|
|
sksec->sclass = SECCLASS_TUN_SOCKET;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_tun_dev_open(void *security)
|
|
{
|
|
struct tun_security_struct *tunsec = security;
|
|
u32 sid = current_sid();
|
|
int err;
|
|
|
|
err = avc_has_perm(&selinux_state,
|
|
sid, tunsec->sid, SECCLASS_TUN_SOCKET,
|
|
TUN_SOCKET__RELABELFROM, NULL);
|
|
if (err)
|
|
return err;
|
|
err = avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_TUN_SOCKET,
|
|
TUN_SOCKET__RELABELTO, NULL);
|
|
if (err)
|
|
return err;
|
|
tunsec->sid = sid;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
int err = 0;
|
|
u32 perm;
|
|
struct nlmsghdr *nlh;
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
|
|
if (skb->len < NLMSG_HDRLEN) {
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
nlh = nlmsg_hdr(skb);
|
|
|
|
err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
|
|
if (err) {
|
|
if (err == -EINVAL) {
|
|
pr_warn_ratelimited("SELinux: unrecognized netlink"
|
|
" message: protocol=%hu nlmsg_type=%hu sclass=%s"
|
|
" pig=%d comm=%s\n",
|
|
sk->sk_protocol, nlh->nlmsg_type,
|
|
secclass_map[sksec->sclass - 1].name,
|
|
task_pid_nr(current), current->comm);
|
|
if (!enforcing_enabled(&selinux_state) ||
|
|
security_get_allow_unknown(&selinux_state))
|
|
err = 0;
|
|
}
|
|
|
|
/* Ignore */
|
|
if (err == -ENOENT)
|
|
err = 0;
|
|
goto out;
|
|
}
|
|
|
|
err = sock_has_perm(sk, perm);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_NETFILTER
|
|
|
|
static unsigned int selinux_ip_forward(struct sk_buff *skb,
|
|
const struct net_device *indev,
|
|
u16 family)
|
|
{
|
|
int err;
|
|
char *addrp;
|
|
u32 peer_sid;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
u8 secmark_active;
|
|
u8 netlbl_active;
|
|
u8 peerlbl_active;
|
|
|
|
if (!selinux_policycap_netpeer())
|
|
return NF_ACCEPT;
|
|
|
|
secmark_active = selinux_secmark_enabled();
|
|
netlbl_active = netlbl_enabled();
|
|
peerlbl_active = selinux_peerlbl_enabled();
|
|
if (!secmark_active && !peerlbl_active)
|
|
return NF_ACCEPT;
|
|
|
|
if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
|
|
return NF_DROP;
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->netif = indev->ifindex;
|
|
ad.u.net->family = family;
|
|
if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
|
|
return NF_DROP;
|
|
|
|
if (peerlbl_active) {
|
|
err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
|
|
addrp, family, peer_sid, &ad);
|
|
if (err) {
|
|
selinux_netlbl_err(skb, family, err, 1);
|
|
return NF_DROP;
|
|
}
|
|
}
|
|
|
|
if (secmark_active)
|
|
if (avc_has_perm(&selinux_state,
|
|
peer_sid, skb->secmark,
|
|
SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
|
|
return NF_DROP;
|
|
|
|
if (netlbl_active)
|
|
/* we do this in the FORWARD path and not the POST_ROUTING
|
|
* path because we want to make sure we apply the necessary
|
|
* labeling before IPsec is applied so we can leverage AH
|
|
* protection */
|
|
if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
|
|
return NF_DROP;
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ipv4_forward(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return selinux_ip_forward(skb, state->in, PF_INET);
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
static unsigned int selinux_ipv6_forward(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return selinux_ip_forward(skb, state->in, PF_INET6);
|
|
}
|
|
#endif /* IPV6 */
|
|
|
|
static unsigned int selinux_ip_output(struct sk_buff *skb,
|
|
u16 family)
|
|
{
|
|
struct sock *sk;
|
|
u32 sid;
|
|
|
|
if (!netlbl_enabled())
|
|
return NF_ACCEPT;
|
|
|
|
/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
|
|
* because we want to make sure we apply the necessary labeling
|
|
* before IPsec is applied so we can leverage AH protection */
|
|
sk = skb->sk;
|
|
if (sk) {
|
|
struct sk_security_struct *sksec;
|
|
|
|
if (sk_listener(sk))
|
|
/* if the socket is the listening state then this
|
|
* packet is a SYN-ACK packet which means it needs to
|
|
* be labeled based on the connection/request_sock and
|
|
* not the parent socket. unfortunately, we can't
|
|
* lookup the request_sock yet as it isn't queued on
|
|
* the parent socket until after the SYN-ACK is sent.
|
|
* the "solution" is to simply pass the packet as-is
|
|
* as any IP option based labeling should be copied
|
|
* from the initial connection request (in the IP
|
|
* layer). it is far from ideal, but until we get a
|
|
* security label in the packet itself this is the
|
|
* best we can do. */
|
|
return NF_ACCEPT;
|
|
|
|
/* standard practice, label using the parent socket */
|
|
sksec = sk->sk_security;
|
|
sid = sksec->sid;
|
|
} else
|
|
sid = SECINITSID_KERNEL;
|
|
if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
|
|
return NF_DROP;
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ipv4_output(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return selinux_ip_output(skb, PF_INET);
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
static unsigned int selinux_ipv6_output(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return selinux_ip_output(skb, PF_INET6);
|
|
}
|
|
#endif /* IPV6 */
|
|
|
|
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
|
|
int ifindex,
|
|
u16 family)
|
|
{
|
|
struct sock *sk = skb_to_full_sk(skb);
|
|
struct sk_security_struct *sksec;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
char *addrp;
|
|
u8 proto;
|
|
|
|
if (sk == NULL)
|
|
return NF_ACCEPT;
|
|
sksec = sk->sk_security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->netif = ifindex;
|
|
ad.u.net->family = family;
|
|
if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
|
|
return NF_DROP;
|
|
|
|
if (selinux_secmark_enabled())
|
|
if (avc_has_perm(&selinux_state,
|
|
sksec->sid, skb->secmark,
|
|
SECCLASS_PACKET, PACKET__SEND, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ip_postroute(struct sk_buff *skb,
|
|
const struct net_device *outdev,
|
|
u16 family)
|
|
{
|
|
u32 secmark_perm;
|
|
u32 peer_sid;
|
|
int ifindex = outdev->ifindex;
|
|
struct sock *sk;
|
|
struct common_audit_data ad;
|
|
struct lsm_network_audit net = {0,};
|
|
char *addrp;
|
|
u8 secmark_active;
|
|
u8 peerlbl_active;
|
|
|
|
/* If any sort of compatibility mode is enabled then handoff processing
|
|
* to the selinux_ip_postroute_compat() function to deal with the
|
|
* special handling. We do this in an attempt to keep this function
|
|
* as fast and as clean as possible. */
|
|
if (!selinux_policycap_netpeer())
|
|
return selinux_ip_postroute_compat(skb, ifindex, family);
|
|
|
|
secmark_active = selinux_secmark_enabled();
|
|
peerlbl_active = selinux_peerlbl_enabled();
|
|
if (!secmark_active && !peerlbl_active)
|
|
return NF_ACCEPT;
|
|
|
|
sk = skb_to_full_sk(skb);
|
|
|
|
#ifdef CONFIG_XFRM
|
|
/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
|
|
* packet transformation so allow the packet to pass without any checks
|
|
* since we'll have another chance to perform access control checks
|
|
* when the packet is on it's final way out.
|
|
* NOTE: there appear to be some IPv6 multicast cases where skb->dst
|
|
* is NULL, in this case go ahead and apply access control.
|
|
* NOTE: if this is a local socket (skb->sk != NULL) that is in the
|
|
* TCP listening state we cannot wait until the XFRM processing
|
|
* is done as we will miss out on the SA label if we do;
|
|
* unfortunately, this means more work, but it is only once per
|
|
* connection. */
|
|
if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
|
|
!(sk && sk_listener(sk)))
|
|
return NF_ACCEPT;
|
|
#endif
|
|
|
|
if (sk == NULL) {
|
|
/* Without an associated socket the packet is either coming
|
|
* from the kernel or it is being forwarded; check the packet
|
|
* to determine which and if the packet is being forwarded
|
|
* query the packet directly to determine the security label. */
|
|
if (skb->skb_iif) {
|
|
secmark_perm = PACKET__FORWARD_OUT;
|
|
if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
|
|
return NF_DROP;
|
|
} else {
|
|
secmark_perm = PACKET__SEND;
|
|
peer_sid = SECINITSID_KERNEL;
|
|
}
|
|
} else if (sk_listener(sk)) {
|
|
/* Locally generated packet but the associated socket is in the
|
|
* listening state which means this is a SYN-ACK packet. In
|
|
* this particular case the correct security label is assigned
|
|
* to the connection/request_sock but unfortunately we can't
|
|
* query the request_sock as it isn't queued on the parent
|
|
* socket until after the SYN-ACK packet is sent; the only
|
|
* viable choice is to regenerate the label like we do in
|
|
* selinux_inet_conn_request(). See also selinux_ip_output()
|
|
* for similar problems. */
|
|
u32 skb_sid;
|
|
struct sk_security_struct *sksec;
|
|
|
|
sksec = sk->sk_security;
|
|
if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
|
|
return NF_DROP;
|
|
/* At this point, if the returned skb peerlbl is SECSID_NULL
|
|
* and the packet has been through at least one XFRM
|
|
* transformation then we must be dealing with the "final"
|
|
* form of labeled IPsec packet; since we've already applied
|
|
* all of our access controls on this packet we can safely
|
|
* pass the packet. */
|
|
if (skb_sid == SECSID_NULL) {
|
|
switch (family) {
|
|
case PF_INET:
|
|
if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
|
|
return NF_ACCEPT;
|
|
break;
|
|
case PF_INET6:
|
|
if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
|
|
return NF_ACCEPT;
|
|
break;
|
|
default:
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
}
|
|
}
|
|
if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
|
|
return NF_DROP;
|
|
secmark_perm = PACKET__SEND;
|
|
} else {
|
|
/* Locally generated packet, fetch the security label from the
|
|
* associated socket. */
|
|
struct sk_security_struct *sksec = sk->sk_security;
|
|
peer_sid = sksec->sid;
|
|
secmark_perm = PACKET__SEND;
|
|
}
|
|
|
|
ad.type = LSM_AUDIT_DATA_NET;
|
|
ad.u.net = &net;
|
|
ad.u.net->netif = ifindex;
|
|
ad.u.net->family = family;
|
|
if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
|
|
return NF_DROP;
|
|
|
|
if (secmark_active)
|
|
if (avc_has_perm(&selinux_state,
|
|
peer_sid, skb->secmark,
|
|
SECCLASS_PACKET, secmark_perm, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
if (peerlbl_active) {
|
|
u32 if_sid;
|
|
u32 node_sid;
|
|
|
|
if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
|
|
return NF_DROP;
|
|
if (avc_has_perm(&selinux_state,
|
|
peer_sid, if_sid,
|
|
SECCLASS_NETIF, NETIF__EGRESS, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
|
|
if (sel_netnode_sid(addrp, family, &node_sid))
|
|
return NF_DROP;
|
|
if (avc_has_perm(&selinux_state,
|
|
peer_sid, node_sid,
|
|
SECCLASS_NODE, NODE__SENDTO, &ad))
|
|
return NF_DROP_ERR(-ECONNREFUSED);
|
|
}
|
|
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static unsigned int selinux_ipv4_postroute(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return selinux_ip_postroute(skb, state->out, PF_INET);
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
static unsigned int selinux_ipv6_postroute(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return selinux_ip_postroute(skb, state->out, PF_INET6);
|
|
}
|
|
#endif /* IPV6 */
|
|
|
|
#endif /* CONFIG_NETFILTER */
|
|
|
|
static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
return selinux_nlmsg_perm(sk, skb);
|
|
}
|
|
|
|
static int ipc_alloc_security(struct kern_ipc_perm *perm,
|
|
u16 sclass)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
|
|
isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
|
|
if (!isec)
|
|
return -ENOMEM;
|
|
|
|
isec->sclass = sclass;
|
|
isec->sid = current_sid();
|
|
perm->security = isec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ipc_free_security(struct kern_ipc_perm *perm)
|
|
{
|
|
struct ipc_security_struct *isec = perm->security;
|
|
perm->security = NULL;
|
|
kfree(isec);
|
|
}
|
|
|
|
static int msg_msg_alloc_security(struct msg_msg *msg)
|
|
{
|
|
struct msg_security_struct *msec;
|
|
|
|
msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
|
|
if (!msec)
|
|
return -ENOMEM;
|
|
|
|
msec->sid = SECINITSID_UNLABELED;
|
|
msg->security = msec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void msg_msg_free_security(struct msg_msg *msg)
|
|
{
|
|
struct msg_security_struct *msec = msg->security;
|
|
|
|
msg->security = NULL;
|
|
kfree(msec);
|
|
}
|
|
|
|
static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
|
|
u32 perms)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = ipc_perms->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = ipc_perms->key;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, isec->sid, isec->sclass, perms, &ad);
|
|
}
|
|
|
|
static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
|
|
{
|
|
return msg_msg_alloc_security(msg);
|
|
}
|
|
|
|
static void selinux_msg_msg_free_security(struct msg_msg *msg)
|
|
{
|
|
msg_msg_free_security(msg);
|
|
}
|
|
|
|
/* message queue security operations */
|
|
static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
rc = ipc_alloc_security(msq, SECCLASS_MSGQ);
|
|
if (rc)
|
|
return rc;
|
|
|
|
isec = msq->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = msq->key;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__CREATE, &ad);
|
|
if (rc) {
|
|
ipc_free_security(msq);
|
|
return rc;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_msg_queue_free_security(struct kern_ipc_perm *msq)
|
|
{
|
|
ipc_free_security(msq);
|
|
}
|
|
|
|
static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = msq->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = msq->key;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__ASSOCIATE, &ad);
|
|
}
|
|
|
|
static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
|
|
{
|
|
int err;
|
|
int perms;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case MSG_INFO:
|
|
/* No specific object, just general system-wide information. */
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), SECINITSID_KERNEL,
|
|
SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
|
|
case IPC_STAT:
|
|
case MSG_STAT:
|
|
case MSG_STAT_ANY:
|
|
perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
|
|
break;
|
|
case IPC_SET:
|
|
perms = MSGQ__SETATTR;
|
|
break;
|
|
case IPC_RMID:
|
|
perms = MSGQ__DESTROY;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
err = ipc_has_perm(msq, perms);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct msg_security_struct *msec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
isec = msq->security;
|
|
msec = msg->security;
|
|
|
|
/*
|
|
* First time through, need to assign label to the message
|
|
*/
|
|
if (msec->sid == SECINITSID_UNLABELED) {
|
|
/*
|
|
* Compute new sid based on current process and
|
|
* message queue this message will be stored in
|
|
*/
|
|
rc = security_transition_sid(&selinux_state, sid, isec->sid,
|
|
SECCLASS_MSG, NULL, &msec->sid);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = msq->key;
|
|
|
|
/* Can this process write to the queue? */
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__WRITE, &ad);
|
|
if (!rc)
|
|
/* Can this process send the message */
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, msec->sid, SECCLASS_MSG,
|
|
MSG__SEND, &ad);
|
|
if (!rc)
|
|
/* Can the message be put in the queue? */
|
|
rc = avc_has_perm(&selinux_state,
|
|
msec->sid, isec->sid, SECCLASS_MSGQ,
|
|
MSGQ__ENQUEUE, &ad);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
|
|
struct task_struct *target,
|
|
long type, int mode)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct msg_security_struct *msec;
|
|
struct common_audit_data ad;
|
|
u32 sid = task_sid(target);
|
|
int rc;
|
|
|
|
isec = msq->security;
|
|
msec = msg->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = msq->key;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, isec->sid,
|
|
SECCLASS_MSGQ, MSGQ__READ, &ad);
|
|
if (!rc)
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, msec->sid,
|
|
SECCLASS_MSG, MSG__RECEIVE, &ad);
|
|
return rc;
|
|
}
|
|
|
|
/* Shared Memory security operations */
|
|
static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
rc = ipc_alloc_security(shp, SECCLASS_SHM);
|
|
if (rc)
|
|
return rc;
|
|
|
|
isec = shp->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = shp->key;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_SHM,
|
|
SHM__CREATE, &ad);
|
|
if (rc) {
|
|
ipc_free_security(shp);
|
|
return rc;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_shm_free_security(struct kern_ipc_perm *shp)
|
|
{
|
|
ipc_free_security(shp);
|
|
}
|
|
|
|
static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = shp->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = shp->key;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_SHM,
|
|
SHM__ASSOCIATE, &ad);
|
|
}
|
|
|
|
/* Note, at this point, shp is locked down */
|
|
static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
|
|
{
|
|
int perms;
|
|
int err;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case SHM_INFO:
|
|
/* No specific object, just general system-wide information. */
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), SECINITSID_KERNEL,
|
|
SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
|
|
case IPC_STAT:
|
|
case SHM_STAT:
|
|
case SHM_STAT_ANY:
|
|
perms = SHM__GETATTR | SHM__ASSOCIATE;
|
|
break;
|
|
case IPC_SET:
|
|
perms = SHM__SETATTR;
|
|
break;
|
|
case SHM_LOCK:
|
|
case SHM_UNLOCK:
|
|
perms = SHM__LOCK;
|
|
break;
|
|
case IPC_RMID:
|
|
perms = SHM__DESTROY;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
err = ipc_has_perm(shp, perms);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_shm_shmat(struct kern_ipc_perm *shp,
|
|
char __user *shmaddr, int shmflg)
|
|
{
|
|
u32 perms;
|
|
|
|
if (shmflg & SHM_RDONLY)
|
|
perms = SHM__READ;
|
|
else
|
|
perms = SHM__READ | SHM__WRITE;
|
|
|
|
return ipc_has_perm(shp, perms);
|
|
}
|
|
|
|
/* Semaphore security operations */
|
|
static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
int rc;
|
|
|
|
rc = ipc_alloc_security(sma, SECCLASS_SEM);
|
|
if (rc)
|
|
return rc;
|
|
|
|
isec = sma->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = sma->key;
|
|
|
|
rc = avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_SEM,
|
|
SEM__CREATE, &ad);
|
|
if (rc) {
|
|
ipc_free_security(sma);
|
|
return rc;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_sem_free_security(struct kern_ipc_perm *sma)
|
|
{
|
|
ipc_free_security(sma);
|
|
}
|
|
|
|
static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
|
|
{
|
|
struct ipc_security_struct *isec;
|
|
struct common_audit_data ad;
|
|
u32 sid = current_sid();
|
|
|
|
isec = sma->security;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IPC;
|
|
ad.u.ipc_id = sma->key;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, isec->sid, SECCLASS_SEM,
|
|
SEM__ASSOCIATE, &ad);
|
|
}
|
|
|
|
/* Note, at this point, sma is locked down */
|
|
static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
|
|
{
|
|
int err;
|
|
u32 perms;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case SEM_INFO:
|
|
/* No specific object, just general system-wide information. */
|
|
return avc_has_perm(&selinux_state,
|
|
current_sid(), SECINITSID_KERNEL,
|
|
SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
|
|
case GETPID:
|
|
case GETNCNT:
|
|
case GETZCNT:
|
|
perms = SEM__GETATTR;
|
|
break;
|
|
case GETVAL:
|
|
case GETALL:
|
|
perms = SEM__READ;
|
|
break;
|
|
case SETVAL:
|
|
case SETALL:
|
|
perms = SEM__WRITE;
|
|
break;
|
|
case IPC_RMID:
|
|
perms = SEM__DESTROY;
|
|
break;
|
|
case IPC_SET:
|
|
perms = SEM__SETATTR;
|
|
break;
|
|
case IPC_STAT:
|
|
case SEM_STAT:
|
|
case SEM_STAT_ANY:
|
|
perms = SEM__GETATTR | SEM__ASSOCIATE;
|
|
break;
|
|
default:
|
|
return 0;
|
|
}
|
|
|
|
err = ipc_has_perm(sma, perms);
|
|
return err;
|
|
}
|
|
|
|
static int selinux_sem_semop(struct kern_ipc_perm *sma,
|
|
struct sembuf *sops, unsigned nsops, int alter)
|
|
{
|
|
u32 perms;
|
|
|
|
if (alter)
|
|
perms = SEM__READ | SEM__WRITE;
|
|
else
|
|
perms = SEM__READ;
|
|
|
|
return ipc_has_perm(sma, perms);
|
|
}
|
|
|
|
static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
|
|
{
|
|
u32 av = 0;
|
|
|
|
av = 0;
|
|
if (flag & S_IRUGO)
|
|
av |= IPC__UNIX_READ;
|
|
if (flag & S_IWUGO)
|
|
av |= IPC__UNIX_WRITE;
|
|
|
|
if (av == 0)
|
|
return 0;
|
|
|
|
return ipc_has_perm(ipcp, av);
|
|
}
|
|
|
|
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
|
|
{
|
|
struct ipc_security_struct *isec = ipcp->security;
|
|
*secid = isec->sid;
|
|
}
|
|
|
|
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
|
|
{
|
|
if (inode)
|
|
inode_doinit_with_dentry(inode, dentry);
|
|
}
|
|
|
|
static int selinux_getprocattr(struct task_struct *p,
|
|
char *name, char **value)
|
|
{
|
|
const struct task_security_struct *__tsec;
|
|
u32 sid;
|
|
int error;
|
|
unsigned len;
|
|
|
|
rcu_read_lock();
|
|
__tsec = __task_cred(p)->security;
|
|
|
|
if (current != p) {
|
|
error = avc_has_perm(&selinux_state,
|
|
current_sid(), __tsec->sid,
|
|
SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
|
|
if (error)
|
|
goto bad;
|
|
}
|
|
|
|
if (!strcmp(name, "current"))
|
|
sid = __tsec->sid;
|
|
else if (!strcmp(name, "prev"))
|
|
sid = __tsec->osid;
|
|
else if (!strcmp(name, "exec"))
|
|
sid = __tsec->exec_sid;
|
|
else if (!strcmp(name, "fscreate"))
|
|
sid = __tsec->create_sid;
|
|
else if (!strcmp(name, "keycreate"))
|
|
sid = __tsec->keycreate_sid;
|
|
else if (!strcmp(name, "sockcreate"))
|
|
sid = __tsec->sockcreate_sid;
|
|
else {
|
|
error = -EINVAL;
|
|
goto bad;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (!sid)
|
|
return 0;
|
|
|
|
error = security_sid_to_context(&selinux_state, sid, value, &len);
|
|
if (error)
|
|
return error;
|
|
return len;
|
|
|
|
bad:
|
|
rcu_read_unlock();
|
|
return error;
|
|
}
|
|
|
|
static int selinux_setprocattr(const char *name, void *value, size_t size)
|
|
{
|
|
struct task_security_struct *tsec;
|
|
struct cred *new;
|
|
u32 mysid = current_sid(), sid = 0, ptsid;
|
|
int error;
|
|
char *str = value;
|
|
|
|
/*
|
|
* Basic control over ability to set these attributes at all.
|
|
*/
|
|
if (!strcmp(name, "exec"))
|
|
error = avc_has_perm(&selinux_state,
|
|
mysid, mysid, SECCLASS_PROCESS,
|
|
PROCESS__SETEXEC, NULL);
|
|
else if (!strcmp(name, "fscreate"))
|
|
error = avc_has_perm(&selinux_state,
|
|
mysid, mysid, SECCLASS_PROCESS,
|
|
PROCESS__SETFSCREATE, NULL);
|
|
else if (!strcmp(name, "keycreate"))
|
|
error = avc_has_perm(&selinux_state,
|
|
mysid, mysid, SECCLASS_PROCESS,
|
|
PROCESS__SETKEYCREATE, NULL);
|
|
else if (!strcmp(name, "sockcreate"))
|
|
error = avc_has_perm(&selinux_state,
|
|
mysid, mysid, SECCLASS_PROCESS,
|
|
PROCESS__SETSOCKCREATE, NULL);
|
|
else if (!strcmp(name, "current"))
|
|
error = avc_has_perm(&selinux_state,
|
|
mysid, mysid, SECCLASS_PROCESS,
|
|
PROCESS__SETCURRENT, NULL);
|
|
else
|
|
error = -EINVAL;
|
|
if (error)
|
|
return error;
|
|
|
|
/* Obtain a SID for the context, if one was specified. */
|
|
if (size && str[0] && str[0] != '\n') {
|
|
if (str[size-1] == '\n') {
|
|
str[size-1] = 0;
|
|
size--;
|
|
}
|
|
error = security_context_to_sid(&selinux_state, value, size,
|
|
&sid, GFP_KERNEL);
|
|
if (error == -EINVAL && !strcmp(name, "fscreate")) {
|
|
if (!has_cap_mac_admin(true)) {
|
|
struct audit_buffer *ab;
|
|
size_t audit_size;
|
|
|
|
/* We strip a nul only if it is at the end, otherwise the
|
|
* context contains a nul and we should audit that */
|
|
if (str[size - 1] == '\0')
|
|
audit_size = size - 1;
|
|
else
|
|
audit_size = size;
|
|
ab = audit_log_start(audit_context(),
|
|
GFP_ATOMIC,
|
|
AUDIT_SELINUX_ERR);
|
|
audit_log_format(ab, "op=fscreate invalid_context=");
|
|
audit_log_n_untrustedstring(ab, value, audit_size);
|
|
audit_log_end(ab);
|
|
|
|
return error;
|
|
}
|
|
error = security_context_to_sid_force(
|
|
&selinux_state,
|
|
value, size, &sid);
|
|
}
|
|
if (error)
|
|
return error;
|
|
}
|
|
|
|
new = prepare_creds();
|
|
if (!new)
|
|
return -ENOMEM;
|
|
|
|
/* Permission checking based on the specified context is
|
|
performed during the actual operation (execve,
|
|
open/mkdir/...), when we know the full context of the
|
|
operation. See selinux_bprm_set_creds for the execve
|
|
checks and may_create for the file creation checks. The
|
|
operation will then fail if the context is not permitted. */
|
|
tsec = new->security;
|
|
if (!strcmp(name, "exec")) {
|
|
tsec->exec_sid = sid;
|
|
} else if (!strcmp(name, "fscreate")) {
|
|
tsec->create_sid = sid;
|
|
} else if (!strcmp(name, "keycreate")) {
|
|
error = avc_has_perm(&selinux_state,
|
|
mysid, sid, SECCLASS_KEY, KEY__CREATE,
|
|
NULL);
|
|
if (error)
|
|
goto abort_change;
|
|
tsec->keycreate_sid = sid;
|
|
} else if (!strcmp(name, "sockcreate")) {
|
|
tsec->sockcreate_sid = sid;
|
|
} else if (!strcmp(name, "current")) {
|
|
error = -EINVAL;
|
|
if (sid == 0)
|
|
goto abort_change;
|
|
|
|
/* Only allow single threaded processes to change context */
|
|
error = -EPERM;
|
|
if (!current_is_single_threaded()) {
|
|
error = security_bounded_transition(&selinux_state,
|
|
tsec->sid, sid);
|
|
if (error)
|
|
goto abort_change;
|
|
}
|
|
|
|
/* Check permissions for the transition. */
|
|
error = avc_has_perm(&selinux_state,
|
|
tsec->sid, sid, SECCLASS_PROCESS,
|
|
PROCESS__DYNTRANSITION, NULL);
|
|
if (error)
|
|
goto abort_change;
|
|
|
|
/* Check for ptracing, and update the task SID if ok.
|
|
Otherwise, leave SID unchanged and fail. */
|
|
ptsid = ptrace_parent_sid();
|
|
if (ptsid != 0) {
|
|
error = avc_has_perm(&selinux_state,
|
|
ptsid, sid, SECCLASS_PROCESS,
|
|
PROCESS__PTRACE, NULL);
|
|
if (error)
|
|
goto abort_change;
|
|
}
|
|
|
|
tsec->sid = sid;
|
|
} else {
|
|
error = -EINVAL;
|
|
goto abort_change;
|
|
}
|
|
|
|
commit_creds(new);
|
|
return size;
|
|
|
|
abort_change:
|
|
abort_creds(new);
|
|
return error;
|
|
}
|
|
|
|
static int selinux_ismaclabel(const char *name)
|
|
{
|
|
return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
|
|
}
|
|
|
|
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
|
|
{
|
|
return security_sid_to_context(&selinux_state, secid,
|
|
secdata, seclen);
|
|
}
|
|
|
|
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
|
|
{
|
|
return security_context_to_sid(&selinux_state, secdata, seclen,
|
|
secid, GFP_KERNEL);
|
|
}
|
|
|
|
static void selinux_release_secctx(char *secdata, u32 seclen)
|
|
{
|
|
kfree(secdata);
|
|
}
|
|
|
|
static void selinux_inode_invalidate_secctx(struct inode *inode)
|
|
{
|
|
struct inode_security_struct *isec = inode->i_security;
|
|
|
|
spin_lock(&isec->lock);
|
|
isec->initialized = LABEL_INVALID;
|
|
spin_unlock(&isec->lock);
|
|
}
|
|
|
|
/*
|
|
* called with inode->i_mutex locked
|
|
*/
|
|
static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
|
|
{
|
|
return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
|
|
}
|
|
|
|
/*
|
|
* called with inode->i_mutex locked
|
|
*/
|
|
static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
|
|
{
|
|
return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
|
|
}
|
|
|
|
static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
|
|
{
|
|
int len = 0;
|
|
len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
|
|
ctx, true);
|
|
if (len < 0)
|
|
return len;
|
|
*ctxlen = len;
|
|
return 0;
|
|
}
|
|
#ifdef CONFIG_KEYS
|
|
|
|
static int selinux_key_alloc(struct key *k, const struct cred *cred,
|
|
unsigned long flags)
|
|
{
|
|
const struct task_security_struct *tsec;
|
|
struct key_security_struct *ksec;
|
|
|
|
ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
|
|
if (!ksec)
|
|
return -ENOMEM;
|
|
|
|
tsec = cred->security;
|
|
if (tsec->keycreate_sid)
|
|
ksec->sid = tsec->keycreate_sid;
|
|
else
|
|
ksec->sid = tsec->sid;
|
|
|
|
k->security = ksec;
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_key_free(struct key *k)
|
|
{
|
|
struct key_security_struct *ksec = k->security;
|
|
|
|
k->security = NULL;
|
|
kfree(ksec);
|
|
}
|
|
|
|
static int selinux_key_permission(key_ref_t key_ref,
|
|
const struct cred *cred,
|
|
unsigned perm)
|
|
{
|
|
struct key *key;
|
|
struct key_security_struct *ksec;
|
|
u32 sid;
|
|
|
|
/* if no specific permissions are requested, we skip the
|
|
permission check. No serious, additional covert channels
|
|
appear to be created. */
|
|
if (perm == 0)
|
|
return 0;
|
|
|
|
sid = cred_sid(cred);
|
|
|
|
key = key_ref_to_ptr(key_ref);
|
|
ksec = key->security;
|
|
|
|
return avc_has_perm(&selinux_state,
|
|
sid, ksec->sid, SECCLASS_KEY, perm, NULL);
|
|
}
|
|
|
|
static int selinux_key_getsecurity(struct key *key, char **_buffer)
|
|
{
|
|
struct key_security_struct *ksec = key->security;
|
|
char *context = NULL;
|
|
unsigned len;
|
|
int rc;
|
|
|
|
rc = security_sid_to_context(&selinux_state, ksec->sid,
|
|
&context, &len);
|
|
if (!rc)
|
|
rc = len;
|
|
*_buffer = context;
|
|
return rc;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_SECURITY_INFINIBAND
|
|
static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
|
|
{
|
|
struct common_audit_data ad;
|
|
int err;
|
|
u32 sid = 0;
|
|
struct ib_security_struct *sec = ib_sec;
|
|
struct lsm_ibpkey_audit ibpkey;
|
|
|
|
err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
|
|
if (err)
|
|
return err;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IBPKEY;
|
|
ibpkey.subnet_prefix = subnet_prefix;
|
|
ibpkey.pkey = pkey_val;
|
|
ad.u.ibpkey = &ibpkey;
|
|
return avc_has_perm(&selinux_state,
|
|
sec->sid, sid,
|
|
SECCLASS_INFINIBAND_PKEY,
|
|
INFINIBAND_PKEY__ACCESS, &ad);
|
|
}
|
|
|
|
static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
|
|
u8 port_num)
|
|
{
|
|
struct common_audit_data ad;
|
|
int err;
|
|
u32 sid = 0;
|
|
struct ib_security_struct *sec = ib_sec;
|
|
struct lsm_ibendport_audit ibendport;
|
|
|
|
err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
|
|
&sid);
|
|
|
|
if (err)
|
|
return err;
|
|
|
|
ad.type = LSM_AUDIT_DATA_IBENDPORT;
|
|
strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
|
|
ibendport.port = port_num;
|
|
ad.u.ibendport = &ibendport;
|
|
return avc_has_perm(&selinux_state,
|
|
sec->sid, sid,
|
|
SECCLASS_INFINIBAND_ENDPORT,
|
|
INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
|
|
}
|
|
|
|
static int selinux_ib_alloc_security(void **ib_sec)
|
|
{
|
|
struct ib_security_struct *sec;
|
|
|
|
sec = kzalloc(sizeof(*sec), GFP_KERNEL);
|
|
if (!sec)
|
|
return -ENOMEM;
|
|
sec->sid = current_sid();
|
|
|
|
*ib_sec = sec;
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_ib_free_security(void *ib_sec)
|
|
{
|
|
kfree(ib_sec);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_BPF_SYSCALL
|
|
static int selinux_bpf(int cmd, union bpf_attr *attr,
|
|
unsigned int size)
|
|
{
|
|
u32 sid = current_sid();
|
|
int ret;
|
|
|
|
switch (cmd) {
|
|
case BPF_MAP_CREATE:
|
|
ret = avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
|
|
NULL);
|
|
break;
|
|
case BPF_PROG_LOAD:
|
|
ret = avc_has_perm(&selinux_state,
|
|
sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
|
|
NULL);
|
|
break;
|
|
default:
|
|
ret = 0;
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static u32 bpf_map_fmode_to_av(fmode_t fmode)
|
|
{
|
|
u32 av = 0;
|
|
|
|
if (fmode & FMODE_READ)
|
|
av |= BPF__MAP_READ;
|
|
if (fmode & FMODE_WRITE)
|
|
av |= BPF__MAP_WRITE;
|
|
return av;
|
|
}
|
|
|
|
/* This function will check the file pass through unix socket or binder to see
|
|
* if it is a bpf related object. And apply correspinding checks on the bpf
|
|
* object based on the type. The bpf maps and programs, not like other files and
|
|
* socket, are using a shared anonymous inode inside the kernel as their inode.
|
|
* So checking that inode cannot identify if the process have privilege to
|
|
* access the bpf object and that's why we have to add this additional check in
|
|
* selinux_file_receive and selinux_binder_transfer_files.
|
|
*/
|
|
static int bpf_fd_pass(struct file *file, u32 sid)
|
|
{
|
|
struct bpf_security_struct *bpfsec;
|
|
struct bpf_prog *prog;
|
|
struct bpf_map *map;
|
|
int ret;
|
|
|
|
if (file->f_op == &bpf_map_fops) {
|
|
map = file->private_data;
|
|
bpfsec = map->security;
|
|
ret = avc_has_perm(&selinux_state,
|
|
sid, bpfsec->sid, SECCLASS_BPF,
|
|
bpf_map_fmode_to_av(file->f_mode), NULL);
|
|
if (ret)
|
|
return ret;
|
|
} else if (file->f_op == &bpf_prog_fops) {
|
|
prog = file->private_data;
|
|
bpfsec = prog->aux->security;
|
|
ret = avc_has_perm(&selinux_state,
|
|
sid, bpfsec->sid, SECCLASS_BPF,
|
|
BPF__PROG_RUN, NULL);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
|
|
{
|
|
u32 sid = current_sid();
|
|
struct bpf_security_struct *bpfsec;
|
|
|
|
bpfsec = map->security;
|
|
return avc_has_perm(&selinux_state,
|
|
sid, bpfsec->sid, SECCLASS_BPF,
|
|
bpf_map_fmode_to_av(fmode), NULL);
|
|
}
|
|
|
|
static int selinux_bpf_prog(struct bpf_prog *prog)
|
|
{
|
|
u32 sid = current_sid();
|
|
struct bpf_security_struct *bpfsec;
|
|
|
|
bpfsec = prog->aux->security;
|
|
return avc_has_perm(&selinux_state,
|
|
sid, bpfsec->sid, SECCLASS_BPF,
|
|
BPF__PROG_RUN, NULL);
|
|
}
|
|
|
|
static int selinux_bpf_map_alloc(struct bpf_map *map)
|
|
{
|
|
struct bpf_security_struct *bpfsec;
|
|
|
|
bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
|
|
if (!bpfsec)
|
|
return -ENOMEM;
|
|
|
|
bpfsec->sid = current_sid();
|
|
map->security = bpfsec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_bpf_map_free(struct bpf_map *map)
|
|
{
|
|
struct bpf_security_struct *bpfsec = map->security;
|
|
|
|
map->security = NULL;
|
|
kfree(bpfsec);
|
|
}
|
|
|
|
static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
|
|
{
|
|
struct bpf_security_struct *bpfsec;
|
|
|
|
bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
|
|
if (!bpfsec)
|
|
return -ENOMEM;
|
|
|
|
bpfsec->sid = current_sid();
|
|
aux->security = bpfsec;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
|
|
{
|
|
struct bpf_security_struct *bpfsec = aux->security;
|
|
|
|
aux->security = NULL;
|
|
kfree(bpfsec);
|
|
}
|
|
#endif
|
|
|
|
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
|
|
LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
|
|
LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
|
|
LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
|
|
LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
|
|
|
|
LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
|
|
LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
|
|
LSM_HOOK_INIT(capget, selinux_capget),
|
|
LSM_HOOK_INIT(capset, selinux_capset),
|
|
LSM_HOOK_INIT(capable, selinux_capable),
|
|
LSM_HOOK_INIT(quotactl, selinux_quotactl),
|
|
LSM_HOOK_INIT(quota_on, selinux_quota_on),
|
|
LSM_HOOK_INIT(syslog, selinux_syslog),
|
|
LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
|
|
|
|
LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
|
|
|
|
LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
|
|
LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
|
|
LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
|
|
|
|
LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
|
|
LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
|
|
LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
|
|
LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
|
|
LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
|
|
LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
|
|
LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
|
|
LSM_HOOK_INIT(sb_mount, selinux_mount),
|
|
LSM_HOOK_INIT(sb_umount, selinux_umount),
|
|
LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
|
|
LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
|
|
LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
|
|
|
|
LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
|
|
LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
|
|
|
|
LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
|
|
LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
|
|
LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
|
|
LSM_HOOK_INIT(inode_create, selinux_inode_create),
|
|
LSM_HOOK_INIT(inode_link, selinux_inode_link),
|
|
LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
|
|
LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
|
|
LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
|
|
LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
|
|
LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
|
|
LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
|
|
LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
|
|
LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
|
|
LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
|
|
LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
|
|
LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
|
|
LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
|
|
LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
|
|
LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
|
|
LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
|
|
LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
|
|
LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
|
|
LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
|
|
LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
|
|
LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
|
|
LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
|
|
LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
|
|
|
|
LSM_HOOK_INIT(file_permission, selinux_file_permission),
|
|
LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
|
|
LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
|
|
LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
|
|
LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
|
|
LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
|
|
LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
|
|
LSM_HOOK_INIT(file_lock, selinux_file_lock),
|
|
LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
|
|
LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
|
|
LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
|
|
LSM_HOOK_INIT(file_receive, selinux_file_receive),
|
|
|
|
LSM_HOOK_INIT(file_open, selinux_file_open),
|
|
|
|
LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
|
|
LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
|
|
LSM_HOOK_INIT(cred_free, selinux_cred_free),
|
|
LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
|
|
LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
|
|
LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
|
|
LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
|
|
LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
|
|
LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
|
|
LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
|
|
LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
|
|
LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
|
|
LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
|
|
LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
|
|
LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
|
|
LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
|
|
LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
|
|
LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
|
|
LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
|
|
LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
|
|
LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
|
|
LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
|
|
LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
|
|
LSM_HOOK_INIT(task_kill, selinux_task_kill),
|
|
LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
|
|
|
|
LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
|
|
LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
|
|
|
|
LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
|
|
LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
|
|
|
|
LSM_HOOK_INIT(msg_queue_alloc_security,
|
|
selinux_msg_queue_alloc_security),
|
|
LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
|
|
LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
|
|
LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
|
|
LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
|
|
LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
|
|
|
|
LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
|
|
LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
|
|
LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
|
|
LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
|
|
LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
|
|
|
|
LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
|
|
LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
|
|
LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
|
|
LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
|
|
LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
|
|
|
|
LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
|
|
|
|
LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
|
|
LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
|
|
|
|
LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
|
|
LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
|
|
LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
|
|
LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
|
|
LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
|
|
LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
|
|
LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
|
|
LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
|
|
|
|
LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
|
|
LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
|
|
|
|
LSM_HOOK_INIT(socket_create, selinux_socket_create),
|
|
LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
|
|
LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
|
|
LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
|
|
LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
|
|
LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
|
|
LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
|
|
LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
|
|
LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
|
|
LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
|
|
LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
|
|
LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
|
|
LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
|
|
LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
|
|
LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
|
|
LSM_HOOK_INIT(socket_getpeersec_stream,
|
|
selinux_socket_getpeersec_stream),
|
|
LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
|
|
LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
|
|
LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
|
|
LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
|
|
LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
|
|
LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
|
|
LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
|
|
LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
|
|
LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
|
|
LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
|
|
LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
|
|
LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
|
|
LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
|
|
LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
|
|
LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
|
|
LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
|
|
LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
|
|
LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
|
|
LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
|
|
LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
|
|
LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
|
|
LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
|
|
#ifdef CONFIG_SECURITY_INFINIBAND
|
|
LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
|
|
LSM_HOOK_INIT(ib_endport_manage_subnet,
|
|
selinux_ib_endport_manage_subnet),
|
|
LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
|
|
LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
|
|
#endif
|
|
#ifdef CONFIG_SECURITY_NETWORK_XFRM
|
|
LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
|
|
LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
|
|
LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
|
|
LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
|
|
LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
|
|
LSM_HOOK_INIT(xfrm_state_alloc_acquire,
|
|
selinux_xfrm_state_alloc_acquire),
|
|
LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
|
|
LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
|
|
LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
|
|
LSM_HOOK_INIT(xfrm_state_pol_flow_match,
|
|
selinux_xfrm_state_pol_flow_match),
|
|
LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
|
|
#endif
|
|
|
|
#ifdef CONFIG_KEYS
|
|
LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
|
|
LSM_HOOK_INIT(key_free, selinux_key_free),
|
|
LSM_HOOK_INIT(key_permission, selinux_key_permission),
|
|
LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
|
|
#endif
|
|
|
|
#ifdef CONFIG_AUDIT
|
|
LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
|
|
LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
|
|
LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
|
|
LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
|
|
#endif
|
|
|
|
#ifdef CONFIG_BPF_SYSCALL
|
|
LSM_HOOK_INIT(bpf, selinux_bpf),
|
|
LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
|
|
LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
|
|
LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
|
|
LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
|
|
LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
|
|
LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
|
|
#endif
|
|
};
|
|
|
|
static __init int selinux_init(void)
|
|
{
|
|
if (!security_module_enable("selinux")) {
|
|
selinux_enabled = 0;
|
|
return 0;
|
|
}
|
|
|
|
if (!selinux_enabled) {
|
|
pr_info("SELinux: Disabled at boot.\n");
|
|
return 0;
|
|
}
|
|
|
|
pr_info("SELinux: Initializing.\n");
|
|
|
|
memset(&selinux_state, 0, sizeof(selinux_state));
|
|
enforcing_set(&selinux_state, selinux_enforcing_boot);
|
|
selinux_state.checkreqprot = selinux_checkreqprot_boot;
|
|
selinux_ss_init(&selinux_state.ss);
|
|
selinux_avc_init(&selinux_state.avc);
|
|
|
|
/* Set the security state for the initial task. */
|
|
cred_init_security();
|
|
|
|
default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
|
|
|
|
sel_inode_cache = kmem_cache_create("selinux_inode_security",
|
|
sizeof(struct inode_security_struct),
|
|
0, SLAB_PANIC, NULL);
|
|
file_security_cache = kmem_cache_create("selinux_file_security",
|
|
sizeof(struct file_security_struct),
|
|
0, SLAB_PANIC, NULL);
|
|
avc_init();
|
|
|
|
avtab_cache_init();
|
|
|
|
ebitmap_cache_init();
|
|
|
|
hashtab_cache_init();
|
|
|
|
security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
|
|
|
|
if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
|
|
panic("SELinux: Unable to register AVC netcache callback\n");
|
|
|
|
if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
|
|
panic("SELinux: Unable to register AVC LSM notifier callback\n");
|
|
|
|
if (selinux_enforcing_boot)
|
|
pr_debug("SELinux: Starting in enforcing mode\n");
|
|
else
|
|
pr_debug("SELinux: Starting in permissive mode\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void delayed_superblock_init(struct super_block *sb, void *unused)
|
|
{
|
|
superblock_doinit(sb, NULL);
|
|
}
|
|
|
|
void selinux_complete_init(void)
|
|
{
|
|
pr_debug("SELinux: Completing initialization.\n");
|
|
|
|
/* Set up any superblocks initialized prior to the policy load. */
|
|
pr_debug("SELinux: Setting up existing superblocks.\n");
|
|
iterate_supers(delayed_superblock_init, NULL);
|
|
}
|
|
|
|
/* SELinux requires early initialization in order to label
|
|
all processes and objects when they are created. */
|
|
DEFINE_LSM(selinux) = {
|
|
.name = "selinux",
|
|
.init = selinux_init,
|
|
};
|
|
|
|
#if defined(CONFIG_NETFILTER)
|
|
|
|
static const struct nf_hook_ops selinux_nf_ops[] = {
|
|
{
|
|
.hook = selinux_ipv4_postroute,
|
|
.pf = NFPROTO_IPV4,
|
|
.hooknum = NF_INET_POST_ROUTING,
|
|
.priority = NF_IP_PRI_SELINUX_LAST,
|
|
},
|
|
{
|
|
.hook = selinux_ipv4_forward,
|
|
.pf = NFPROTO_IPV4,
|
|
.hooknum = NF_INET_FORWARD,
|
|
.priority = NF_IP_PRI_SELINUX_FIRST,
|
|
},
|
|
{
|
|
.hook = selinux_ipv4_output,
|
|
.pf = NFPROTO_IPV4,
|
|
.hooknum = NF_INET_LOCAL_OUT,
|
|
.priority = NF_IP_PRI_SELINUX_FIRST,
|
|
},
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
{
|
|
.hook = selinux_ipv6_postroute,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_POST_ROUTING,
|
|
.priority = NF_IP6_PRI_SELINUX_LAST,
|
|
},
|
|
{
|
|
.hook = selinux_ipv6_forward,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_FORWARD,
|
|
.priority = NF_IP6_PRI_SELINUX_FIRST,
|
|
},
|
|
{
|
|
.hook = selinux_ipv6_output,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_LOCAL_OUT,
|
|
.priority = NF_IP6_PRI_SELINUX_FIRST,
|
|
},
|
|
#endif /* IPV6 */
|
|
};
|
|
|
|
static int __net_init selinux_nf_register(struct net *net)
|
|
{
|
|
return nf_register_net_hooks(net, selinux_nf_ops,
|
|
ARRAY_SIZE(selinux_nf_ops));
|
|
}
|
|
|
|
static void __net_exit selinux_nf_unregister(struct net *net)
|
|
{
|
|
nf_unregister_net_hooks(net, selinux_nf_ops,
|
|
ARRAY_SIZE(selinux_nf_ops));
|
|
}
|
|
|
|
static struct pernet_operations selinux_net_ops = {
|
|
.init = selinux_nf_register,
|
|
.exit = selinux_nf_unregister,
|
|
};
|
|
|
|
static int __init selinux_nf_ip_init(void)
|
|
{
|
|
int err;
|
|
|
|
if (!selinux_enabled)
|
|
return 0;
|
|
|
|
pr_debug("SELinux: Registering netfilter hooks\n");
|
|
|
|
err = register_pernet_subsys(&selinux_net_ops);
|
|
if (err)
|
|
panic("SELinux: register_pernet_subsys: error %d\n", err);
|
|
|
|
return 0;
|
|
}
|
|
__initcall(selinux_nf_ip_init);
|
|
|
|
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
|
|
static void selinux_nf_ip_exit(void)
|
|
{
|
|
pr_debug("SELinux: Unregistering netfilter hooks\n");
|
|
|
|
unregister_pernet_subsys(&selinux_net_ops);
|
|
}
|
|
#endif
|
|
|
|
#else /* CONFIG_NETFILTER */
|
|
|
|
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
|
|
#define selinux_nf_ip_exit()
|
|
#endif
|
|
|
|
#endif /* CONFIG_NETFILTER */
|
|
|
|
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
|
|
int selinux_disable(struct selinux_state *state)
|
|
{
|
|
if (state->initialized) {
|
|
/* Not permitted after initial policy load. */
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (state->disabled) {
|
|
/* Only do this once. */
|
|
return -EINVAL;
|
|
}
|
|
|
|
state->disabled = 1;
|
|
|
|
pr_info("SELinux: Disabled at runtime.\n");
|
|
|
|
selinux_enabled = 0;
|
|
|
|
security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
|
|
|
|
/* Try to destroy the avc node cache */
|
|
avc_disable();
|
|
|
|
/* Unregister netfilter hooks. */
|
|
selinux_nf_ip_exit();
|
|
|
|
/* Unregister selinuxfs. */
|
|
exit_sel_fs();
|
|
|
|
return 0;
|
|
}
|
|
#endif
|