hooks.c 167.5 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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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>
 *					   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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 *
 *	This program is free software; you can redistribute it and/or modify
 *	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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 */

#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>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
#include <linux/spinlock.h>
#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>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#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>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
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#include <net/netlink.h>
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#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#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>
#include <linux/shm.h>
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#include "avc.h"
#include "objsec.h"
#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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/* 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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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
{
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	unsigned long enforcing;
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	if (!kstrtoul(str, 0, &enforcing))
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		selinux_enforcing = enforcing ? 1 : 0;
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	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

static int __init selinux_enabled_setup(char *str)
{
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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;
}
__setup("selinux=", selinux_enabled_setup);
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#else
int selinux_enabled = 1;
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#endif

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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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/**
 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 *
 * Description:
 * This function checks the SECMARK reference counter to see if any SECMARK
 * targets are currently configured, if the reference counter is greater than
 * 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
 * policy capability is enabled, SECMARK is always considered enabled.
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 *
 */
static int selinux_secmark_enabled(void)
{
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	return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
}

/**
 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 *
 * Description:
 * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 * (1) if any are enabled or false (0) if neither are enabled.  If the
 * always_check_network policy capability is enabled, peer labeling
 * is always considered enabled.
 *
 */
static int selinux_peerlbl_enabled(void)
{
	return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
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}

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static int selinux_netcache_avc_callback(u32 event)
{
	if (event == AVC_CALLBACK_RESET) {
		sel_netif_flush();
		sel_netnode_flush();
		sel_netport_flush();
		synchronize_net();
	}
	return 0;
}

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static int selinux_lsm_notifier_avc_callback(u32 event)
{
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	if (event == AVC_CALLBACK_RESET) {
		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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/*
 * initialise the security for the init task
 */
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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/*
 * get the security ID of a set of credentials
 */
static inline u32 cred_sid(const struct cred *cred)
{
	const struct task_security_struct *tsec;

	tsec = cred->security;
	return tsec->sid;
}

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/*
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 * get the objective security ID of a task
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 */
static inline u32 task_sid(const struct task_struct *task)
{
	u32 sid;

	rcu_read_lock();
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	sid = cred_sid(__task_cred(task));
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	rcu_read_unlock();
	return sid;
}

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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)
{
	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)
		return -ENOMEM;

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	spin_lock_init(&isec->lock);
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	INIT_LIST_HEAD(&isec->list);
	isec->inode = inode;
	isec->sid = SECINITSID_UNLABELED;
	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;

	return 0;
}

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static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);

/*
 * Try reloading inode security labels that have been marked as invalid.  The
 * @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 @opt_dentry parameter should be set to a dentry of the inode;
 * when no dentry is available, set it to NULL instead.
 */
static int __inode_security_revalidate(struct inode *inode,
				       struct dentry *opt_dentry,
				       bool may_sleep)
{
	struct inode_security_struct *isec = inode->i_security;

	might_sleep_if(may_sleep);

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	if (ss_initialized && isec->initialized != LABEL_INITIALIZED) {
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		if (!may_sleep)
			return -ECHILD;

		/*
		 * Try reloading the inode security label.  This will fail if
		 * @opt_dentry is NULL and no dentry for this inode can be
		 * found; in that case, continue using the old label.
		 */
		inode_doinit_with_dentry(inode, opt_dentry);
	}
	return 0;
}

static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
{
	return inode->i_security;
}

static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
{
	int error;

	error = __inode_security_revalidate(inode, NULL, !rcu);
	if (error)
		return ERR_PTR(error);
	return inode->i_security;
}

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/*
 * Get the security label of an inode.
 */
static struct inode_security_struct *inode_security(struct inode *inode)
{
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	__inode_security_revalidate(inode, NULL, true);
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	return inode->i_security;
}

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static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
{
	struct inode *inode = d_backing_inode(dentry);

	return inode->i_security;
}

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/*
 * Get the security label of a dentry's backing inode.
 */
static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
{
	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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static void inode_free_rcu(struct rcu_head *head)
{
	struct inode_security_struct *isec;

	isec = container_of(head, struct inode_security_struct, rcu);
	kmem_cache_free(sel_inode_cache, isec);
}

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static void inode_free_security(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec = inode->i_sb->s_security;

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	/*
	 * As not all inode security structures are in a list, we check for
	 * empty list outside of the lock to make sure that we won't waste
	 * time taking a lock doing nothing.
	 *
	 * The list_del_init() function can be safely called more than once.
	 * It should not be possible for this function to be called with
	 * concurrent list_add(), but for better safety against future changes
	 * in the code, we use list_empty_careful() here.
	 */
	if (!list_empty_careful(&isec->list)) {
		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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	/*
	 * The inode may still be referenced in a path walk and
	 * a call to selinux_inode_permission() can be made
	 * after inode_free_security() is called. Ideally, the VFS
	 * wouldn't do this, but fixing that is a much harder
	 * job. For now, simply free the i_security via RCU, and
	 * leave the current inode->i_security pointer intact.
	 * The inode will be freed after the RCU grace period too.
	 */
	call_rcu(&isec->rcu, inode_free_rcu);
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}

static int file_alloc_security(struct file *file)
{
	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)
		return -ENOMEM;

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	fsec->sid = sid;
	fsec->fown_sid = sid;
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	file->f_security = fsec;

	return 0;
}

static void file_free_security(struct file *file)
{
	struct file_security_struct *fsec = file->f_security;
	file->f_security = NULL;
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	kmem_cache_free(file_security_cache, fsec);
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}

static int superblock_alloc_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec;

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	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
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	if (!sbsec)
		return -ENOMEM;

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	mutex_init(&sbsec->lock);
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	INIT_LIST_HEAD(&sbsec->isec_head);
	spin_lock_init(&sbsec->isec_lock);
	sbsec->sb = sb;
	sbsec->sid = SECINITSID_UNLABELED;
	sbsec->def_sid = SECINITSID_FILE;
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	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
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	sb->s_security = sbsec;

	return 0;
}

static void superblock_free_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;
	sb->s_security = NULL;
	kfree(sbsec);
}

static inline int inode_doinit(struct inode *inode)
{
	return inode_doinit_with_dentry(inode, NULL);
}

enum {
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	Opt_error = -1,
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	Opt_context = 1,
	Opt_fscontext = 2,
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	Opt_defcontext = 3,
	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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static const match_table_t tokens = {
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	{Opt_context, CONTEXT_STR "%s"},
	{Opt_fscontext, FSCONTEXT_STR "%s"},
	{Opt_defcontext, DEFCONTEXT_STR "%s"},
	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
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	{Opt_labelsupport, LABELSUPP_STR},
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	{Opt_error, NULL},
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};

#define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"

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static int may_context_mount_sb_relabel(u32 sid,
			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;

	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELTO, NULL);
	return rc;
}

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static int may_context_mount_inode_relabel(u32 sid,
			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;
	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__ASSOCIATE, NULL);
	return rc;
}

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static int selinux_is_sblabel_mnt(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;

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	return sbsec->behavior == SECURITY_FS_USE_XATTR ||
		sbsec->behavior == SECURITY_FS_USE_TRANS ||
		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 */
		!strcmp(sb->s_type->name, "sysfs") ||
		!strcmp(sb->s_type->name, "pstore") ||
		!strcmp(sb->s_type->name, "debugfs") ||
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		!strcmp(sb->s_type->name, "tracefs") ||
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		!strcmp(sb->s_type->name, "rootfs") ||
		(selinux_policycap_cgroupseclabel &&
		 (!strcmp(sb->s_type->name, "cgroup") ||
		  !strcmp(sb->s_type->name, "cgroup2")));
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}

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static int sb_finish_set_opts(struct super_block *sb)
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{
	struct superblock_security_struct *sbsec = sb->s_security;
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	struct dentry *root = sb->s_root;
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	struct inode *root_inode = d_backing_inode(root);
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	int rc = 0;
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	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. */
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		if (!(root_inode->i_opflags & IOP_XATTR)) {
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			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
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			rc = -EOPNOTSUPP;
			goto out;
		}
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		rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
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		if (rc < 0 && rc != -ENODATA) {
			if (rc == -EOPNOTSUPP)
				printk(KERN_WARNING "SELinux: (dev %s, type "
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				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
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			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
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				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
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			goto out;
		}
	}
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	sbsec->flags |= SE_SBINITIALIZED;
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	/*
	 * 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.
	 */
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	if (selinux_is_sblabel_mnt(sb))
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		sbsec->flags |= SBLABEL_MNT;
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	else
		sbsec->flags &= ~SBLABEL_MNT;
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	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
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	/* 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;
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		list_del_init(&isec->list);
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		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;
}
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/*
 * 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,
575
				struct security_mnt_opts *opts)
576 577 578 579 580 581
{
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	char *context = NULL;
	u32 len;
	char tmp;
L
Linus Torvalds 已提交
582

583
	security_init_mnt_opts(opts);
L
Linus Torvalds 已提交
584

585
	if (!(sbsec->flags & SE_SBINITIALIZED))
586
		return -EINVAL;
L
Linus Torvalds 已提交
587

588 589
	if (!ss_initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
590

591 592 593
	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

594
	tmp = sbsec->flags & SE_MNTMASK;
595
	/* count the number of mount options for this sb */
596
	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
597
		if (tmp & 0x01)
598
			opts->num_mnt_opts++;
599 600
		tmp >>= 1;
	}
601
	/* Check if the Label support flag is set */
602
	if (sbsec->flags & SBLABEL_MNT)
603
		opts->num_mnt_opts++;
L
Linus Torvalds 已提交
604

605 606
	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
607 608 609
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
610

611 612
	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
613 614 615
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
616

617 618 619 620 621
	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
622 623
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
624 625 626 627 628
	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
629 630
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
631 632 633 634 635
	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
636 637
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
638 639
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
640 641
		struct dentry *root = sbsec->sb->s_root;
		struct inode_security_struct *isec = backing_inode_security(root);
642

643 644 645
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
646 647
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
648
	}
649
	if (sbsec->flags & SBLABEL_MNT) {
650
		opts->mnt_opts[i] = NULL;
651
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
652
	}
L
Linus Torvalds 已提交
653

654
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
655

656 657 658
	return 0;

out_free:
659
	security_free_mnt_opts(opts);
660 661
	return rc;
}
L
Linus Torvalds 已提交
662

663 664 665
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
666 667
	char mnt_flags = sbsec->flags & SE_MNTMASK;

668
	/* check if the old mount command had the same options */
669
	if (sbsec->flags & SE_SBINITIALIZED)
670 671 672 673 674 675 676
		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
	 */
677 678
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
679 680 681
			return 1;
	return 0;
}
682

683 684 685 686
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
687
static int selinux_set_mnt_opts(struct super_block *sb,
688 689 690
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
691
{
692
	const struct cred *cred = current_cred();
693 694
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
695
	const char *name = sb->s_type->name;
696
	struct dentry *root = sbsec->sb->s_root;
697
	struct inode_security_struct *root_isec;
698 699
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
700 701 702
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
703 704 705 706 707 708 709 710 711 712 713

	mutex_lock(&sbsec->lock);

	if (!ss_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;
E
Eric Paris 已提交
714 715
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
716
		goto out;
717
	}
718 719 720 721 722 723
	if (kern_flags && !set_kern_flags) {
		/* Specifying internal flags without providing a place to
		 * place the results is not allowed */
		rc = -EINVAL;
		goto out;
	}
L
Linus Torvalds 已提交
724

725 726 727 728 729 730 731 732 733 734 735
	/*
	 * 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)
	 */
736
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
737
	    && (num_opts == 0))
738
		goto out;
739

740 741
	root_isec = backing_inode_security_novalidate(root);

742 743 744 745 746 747 748
	/*
	 * 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;
749

750
		if (flags[i] == SBLABEL_MNT)
751
			continue;
752
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
L
Linus Torvalds 已提交
753
		if (rc) {
754
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
755 756
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800
			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;
L
Linus Torvalds 已提交
801
		}
802 803
	}

804
	if (sbsec->flags & SE_SBINITIALIZED) {
805
		/* previously mounted with options, but not on this attempt? */
806
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
807 808 809 810 811
			goto out_double_mount;
		rc = 0;
		goto out;
	}

812
	if (strcmp(sb->s_type->name, "proc") == 0)
813 814
		sbsec->flags |= SE_SBPROC | SE_SBGENFS;

815 816 817
	if (!strcmp(sb->s_type->name, "debugfs") ||
	    !strcmp(sb->s_type->name, "sysfs") ||
	    !strcmp(sb->s_type->name, "pstore"))
818
		sbsec->flags |= SE_SBGENFS;
819

820 821 822 823 824
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
825
		rc = security_fs_use(sb);
826 827 828 829 830 831
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
832
	}
833 834

	/*
835 836 837
	 * 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.
838
	 */
839 840 841 842
	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")) {
843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858
		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(current_sid(), current_sid(),
						     SECCLASS_FILE, NULL,
						     &sbsec->mntpoint_sid);
			if (rc)
				goto out;
		}
		goto out_set_opts;
	}

859 860
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
861
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
862
		if (rc)
863
			goto out;
L
Linus Torvalds 已提交
864

865
		sbsec->sid = fscontext_sid;
866 867 868 869 870 871 872
	}

	/*
	 * 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.
	 */
873 874 875 876 877
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

878 879
	if (context_sid) {
		if (!fscontext_sid) {
880 881
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
882
			if (rc)
883 884
				goto out;
			sbsec->sid = context_sid;
885
		} else {
886 887
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
888
			if (rc)
889
				goto out;
890
		}
891 892
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
893

894
		sbsec->mntpoint_sid = context_sid;
895
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
896 897
	}

898
	if (rootcontext_sid) {
899 900
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
901
		if (rc)
902
			goto out;
903

904
		root_isec->sid = rootcontext_sid;
905
		root_isec->initialized = LABEL_INITIALIZED;
906 907
	}

908
	if (defcontext_sid) {
909 910
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
911 912 913 914
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
915 916
		}

917 918
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
919
							     sbsec, cred);
920 921 922
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
923

924
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
925 926
	}

927
out_set_opts:
928
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
929
out:
930
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
931
	return rc;
932 933 934
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
935
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
936
	goto out;
L
Linus Torvalds 已提交
937 938
}

939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955
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) {
956 957
		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
958 959 960 961 962 963 964 965 966 967 968 969
		if (oldroot->sid != newroot->sid)
			goto mismatch;
	}
	return 0;
mismatch:
	printk(KERN_WARNING "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,
970 971 972
					struct super_block *newsb,
					unsigned long kern_flags,
					unsigned long *set_kern_flags)
L
Linus Torvalds 已提交
973
{
974
	int rc = 0;
975 976
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
977

978 979 980
	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
L
Linus Torvalds 已提交
981

982 983
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
984
	 * mount options.  thus we can safely deal with this superblock later
985
	 */
986
	if (!ss_initialized)
987
		return 0;
988

989 990 991 992 993 994 995
	/*
	 * Specifying internal flags without providing a place to
	 * place the results is not allowed.
	 */
	if (kern_flags && !set_kern_flags)
		return -EINVAL;

996
	/* how can we clone if the old one wasn't set up?? */
997
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
998

999
	/* if fs is reusing a sb, make sure that the contexts match */
1000
	if (newsbsec->flags & SE_SBINITIALIZED)
1001
		return selinux_cmp_sb_context(oldsb, newsb);
1002

1003 1004 1005 1006 1007 1008 1009 1010
	mutex_lock(&newsbsec->lock);

	newsbsec->flags = oldsbsec->flags;

	newsbsec->sid = oldsbsec->sid;
	newsbsec->def_sid = oldsbsec->def_sid;
	newsbsec->behavior = oldsbsec->behavior;

1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022
	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
		rc = security_fs_use(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;
	}

1023 1024 1025 1026 1027 1028
	if (set_context) {
		u32 sid = oldsbsec->mntpoint_sid;

		if (!set_fscontext)
			newsbsec->sid = sid;
		if (!set_rootcontext) {
1029
			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1030 1031 1032
			newisec->sid = sid;
		}
		newsbsec->mntpoint_sid = sid;
L
Linus Torvalds 已提交
1033
	}
1034
	if (set_rootcontext) {
1035 1036
		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
L
Linus Torvalds 已提交
1037

1038
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
1039 1040
	}

1041
	sb_finish_set_opts(newsb);
1042
out:
1043
	mutex_unlock(&newsbsec->lock);
1044
	return rc;
1045 1046
}

1047 1048
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
1049
{
1050
	char *p;
1051 1052
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
1053
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
1054

1055
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
1056

1057 1058 1059 1060
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
1061

1062 1063
		if (!*p)
			continue;
L
Linus Torvalds 已提交
1064

1065
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
1066

1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118
		switch (token) {
		case Opt_context:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING 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;
				printk(KERN_WARNING 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;
				printk(KERN_WARNING 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;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			defcontext = match_strdup(&args[0]);
			if (!defcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;
1119 1120
		case Opt_labelsupport:
			break;
1121 1122 1123 1124
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
1125 1126 1127

		}
	}
1128

1129
	rc = -ENOMEM;
1130
	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1131 1132 1133
	if (!opts->mnt_opts)
		goto out_err;

1134 1135
	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
				       GFP_KERNEL);
1136 1137 1138 1139 1140
	if (!opts->mnt_opts_flags) {
		kfree(opts->mnt_opts);
		goto out_err;
	}

1141
	if (fscontext) {
1142 1143
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1144 1145
	}
	if (context) {
1146 1147
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1148 1149
	}
	if (rootcontext) {
1150 1151
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1152 1153
	}
	if (defcontext) {
1154 1155
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1156 1157
	}

1158 1159 1160
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1161 1162 1163 1164 1165
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1166 1167
	return rc;
}
1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188
/*
 * 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:
1189
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1190 1191 1192 1193 1194

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1195

A
Adrian Bunk 已提交
1196 1197
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1198 1199 1200 1201 1202
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1203 1204 1205 1206 1207 1208
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222

		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;
1223
		case SBLABEL_MNT:
1224 1225 1226
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1227 1228
		default:
			BUG();
1229
			return;
1230 1231 1232 1233 1234 1235
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
1236
		seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247
		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);
1248 1249 1250 1251
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1252
		return rc;
1253
	}
1254 1255 1256 1257 1258 1259 1260 1261

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284
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;
}

1285 1286 1287 1288 1289 1290 1291 1292 1293 1294
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);
}

L
Linus Torvalds 已提交
1295 1296
static inline u16 socket_type_to_security_class(int family, int type, int protocol)
{
1297 1298
	int extsockclass = selinux_policycap_extsockclass;

L
Linus Torvalds 已提交
1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312
	switch (family) {
	case PF_UNIX:
		switch (type) {
		case SOCK_STREAM:
		case SOCK_SEQPACKET:
			return SECCLASS_UNIX_STREAM_SOCKET;
		case SOCK_DGRAM:
			return SECCLASS_UNIX_DGRAM_SOCKET;
		}
		break;
	case PF_INET:
	case PF_INET6:
		switch (type) {
		case SOCK_STREAM:
1313
		case SOCK_SEQPACKET:
1314 1315
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
1316 1317
			else if (extsockclass && protocol == IPPROTO_SCTP)
				return SECCLASS_SCTP_SOCKET;
1318 1319
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1320
		case SOCK_DGRAM:
1321 1322
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
1323 1324
			else if (extsockclass && (protocol == IPPROTO_ICMP ||
						  protocol == IPPROTO_ICMPV6))
1325
				return SECCLASS_ICMP_SOCKET;
1326 1327
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1328 1329
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1330
		default:
L
Linus Torvalds 已提交
1331 1332 1333 1334 1335 1336 1337
			return SECCLASS_RAWIP_SOCKET;
		}
		break;
	case PF_NETLINK:
		switch (protocol) {
		case NETLINK_ROUTE:
			return SECCLASS_NETLINK_ROUTE_SOCKET;
1338
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1339 1340 1341 1342 1343 1344 1345
			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;
1346 1347
		case NETLINK_ISCSI:
			return SECCLASS_NETLINK_ISCSI_SOCKET;
L
Linus Torvalds 已提交
1348 1349
		case NETLINK_AUDIT:
			return SECCLASS_NETLINK_AUDIT_SOCKET;
1350 1351 1352 1353 1354 1355
		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;
L
Linus Torvalds 已提交
1356 1357
		case NETLINK_DNRTMSG:
			return SECCLASS_NETLINK_DNRT_SOCKET;
1358 1359
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1360 1361 1362 1363 1364 1365 1366 1367
		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;
L
Linus Torvalds 已提交
1368 1369 1370 1371 1372 1373 1374
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1375 1376
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1377 1378
	}

1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432
	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;
1433 1434 1435
		case PF_SMC:
			return SECCLASS_SMC_SOCKET;
#if PF_MAX > 44
1436 1437 1438 1439 1440
#error New address family defined, please update this function.
#endif
		}
	}

L
Linus Torvalds 已提交
1441 1442 1443
	return SECCLASS_SOCKET;
}

1444 1445 1446 1447
static int selinux_genfs_get_sid(struct dentry *dentry,
				 u16 tclass,
				 u16 flags,
				 u32 *sid)
L
Linus Torvalds 已提交
1448
{
1449
	int rc;
1450
	struct super_block *sb = dentry->d_sb;
1451
	char *buffer, *path;
L
Linus Torvalds 已提交
1452

1453
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1454 1455 1456
	if (!buffer)
		return -ENOMEM;

1457 1458 1459 1460
	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
	if (IS_ERR(path))
		rc = PTR_ERR(path);
	else {
1461 1462 1463 1464 1465 1466 1467 1468
		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++;
			}
1469
		}
1470
		rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
L
Linus Torvalds 已提交
1471 1472 1473 1474 1475 1476 1477 1478 1479 1480
	}
	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;
1481 1482
	u32 task_sid, sid = 0;
	u16 sclass;
L
Linus Torvalds 已提交
1483 1484 1485 1486 1487 1488
	struct dentry *dentry;
#define INITCONTEXTLEN 255
	char *context = NULL;
	unsigned len = 0;
	int rc = 0;

1489
	if (isec->initialized == LABEL_INITIALIZED)
1490
		return 0;
L
Linus Torvalds 已提交
1491

1492
	spin_lock(&isec->lock);
1493
	if (isec->initialized == LABEL_INITIALIZED)
1494
		goto out_unlock;
L
Linus Torvalds 已提交
1495

1496 1497 1498
	if (isec->sclass == SECCLASS_FILE)
		isec->sclass = inode_mode_to_security_class(inode->i_mode);

L
Linus Torvalds 已提交
1499
	sbsec = inode->i_sb->s_security;
1500
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1501 1502 1503 1504 1505 1506 1507
		/* 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);
1508
		goto out_unlock;
L
Linus Torvalds 已提交
1509 1510
	}

1511 1512 1513 1514 1515 1516
	sclass = isec->sclass;
	task_sid = isec->task_sid;
	sid = isec->sid;
	isec->initialized = LABEL_PENDING;
	spin_unlock(&isec->lock);

L
Linus Torvalds 已提交
1517
	switch (sbsec->behavior) {
1518 1519
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1520
	case SECURITY_FS_USE_XATTR:
1521
		if (!(inode->i_opflags & IOP_XATTR)) {
1522
			sid = sbsec->def_sid;
L
Linus Torvalds 已提交
1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534
			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. */
			dentry = d_find_alias(inode);
		}
		if (!dentry) {
1535 1536 1537 1538 1539 1540 1541 1542 1543
			/*
			 * 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.
			 */
1544
			goto out;
L
Linus Torvalds 已提交
1545 1546 1547
		}

		len = INITCONTEXTLEN;
1548
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1549 1550 1551
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1552
			goto out;
L
Linus Torvalds 已提交
1553
		}
1554
		context[len] = '\0';
1555
		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
L
Linus Torvalds 已提交
1556
		if (rc == -ERANGE) {
1557 1558
			kfree(context);

L
Linus Torvalds 已提交
1559
			/* Need a larger buffer.  Query for the right size. */
1560
			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
L
Linus Torvalds 已提交
1561 1562
			if (rc < 0) {
				dput(dentry);
1563
				goto out;
L
Linus Torvalds 已提交
1564 1565
			}
			len = rc;
1566
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1567 1568 1569
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1570
				goto out;
L
Linus Torvalds 已提交
1571
			}
1572
			context[len] = '\0';
1573
			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
L
Linus Torvalds 已提交
1574 1575 1576 1577
		}
		dput(dentry);
		if (rc < 0) {
			if (rc != -ENODATA) {
E
Eric Paris 已提交
1578
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1579
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1580 1581
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1582
				goto out;
L
Linus Torvalds 已提交
1583 1584 1585 1586 1587
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1588
			rc = security_context_to_sid_default(context, rc, &sid,
1589 1590
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1591
			if (rc) {
1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_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 {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
Linus Torvalds 已提交
1605 1606 1607 1608 1609 1610 1611 1612 1613
				kfree(context);
				/* Leave with the unlabeled SID */
				rc = 0;
				break;
			}
		}
		kfree(context);
		break;
	case SECURITY_FS_USE_TASK:
1614
		sid = task_sid;
L
Linus Torvalds 已提交
1615 1616 1617
		break;
	case SECURITY_FS_USE_TRANS:
		/* Default to the fs SID. */
1618
		sid = sbsec->sid;
L
Linus Torvalds 已提交
1619 1620

		/* Try to obtain a transition SID. */
1621
		rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid);
L
Linus Torvalds 已提交
1622
		if (rc)
1623
			goto out;
L
Linus Torvalds 已提交
1624
		break;
1625
	case SECURITY_FS_USE_MNTPOINT:
1626
		sid = sbsec->mntpoint_sid;
1627
		break;
L
Linus Torvalds 已提交
1628
	default:
1629
		/* Default to the fs superblock SID. */
1630
		sid = sbsec->sid;
L
Linus Torvalds 已提交
1631

1632
		if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652
			/* 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. */
				dentry = d_find_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)
1653 1654
				goto out;
			rc = selinux_genfs_get_sid(dentry, sclass,
1655
						   sbsec->flags, &sid);
1656 1657
			dput(dentry);
			if (rc)
1658
				goto out;
L
Linus Torvalds 已提交
1659 1660 1661 1662
		}
		break;
	}

1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673
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;
	}
L
Linus Torvalds 已提交
1674

1675
out_unlock:
1676
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706
	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;
}

1707 1708 1709 1710
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1711
/* Check whether a task is allowed to use a capability. */
1712
static int cred_has_capability(const struct cred *cred,
1713
			       int cap, int audit, bool initns)
L
Linus Torvalds 已提交
1714
{
1715
	struct common_audit_data ad;
1716
	struct av_decision avd;
1717
	u16 sclass;
1718
	u32 sid = cred_sid(cred);
1719
	u32 av = CAP_TO_MASK(cap);
1720
	int rc;
L
Linus Torvalds 已提交
1721

1722
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1723 1724
	ad.u.cap = cap;

1725 1726
	switch (CAP_TO_INDEX(cap)) {
	case 0:
1727
		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1728 1729
		break;
	case 1:
1730
		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1731 1732 1733 1734 1735
		break;
	default:
		printk(KERN_ERR
		       "SELinux:  out of range capability %d\n", cap);
		BUG();
1736
		return -EINVAL;
1737
	}
1738

1739
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1740
	if (audit == SECURITY_CAP_AUDIT) {
1741
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1742 1743 1744
		if (rc2)
			return rc2;
	}
1745
	return rc;
L
Linus Torvalds 已提交
1746 1747 1748 1749 1750
}

/* 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). */
1751
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1752 1753
			  struct inode *inode,
			  u32 perms,
1754
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1755 1756
{
	struct inode_security_struct *isec;
1757
	u32 sid;
L
Linus Torvalds 已提交
1758

1759 1760
	validate_creds(cred);

1761
	if (unlikely(IS_PRIVATE(inode)))
1762 1763
		return 0;

1764
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1765 1766
	isec = inode->i_security;

1767
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1768 1769 1770 1771 1772
}

/* 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. */
1773
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1774 1775 1776
				  struct dentry *dentry,
				  u32 av)
{
1777
	struct inode *inode = d_backing_inode(dentry);
1778
	struct common_audit_data ad;
1779

1780
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1781
	ad.u.dentry = dentry;
1782
	__inode_security_revalidate(inode, dentry, true);
1783
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1784 1785 1786 1787 1788 1789
}

/* 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,
1790
				const struct path *path,
E
Eric Paris 已提交
1791 1792
				u32 av)
{
1793
	struct inode *inode = d_backing_inode(path->dentry);
E
Eric Paris 已提交
1794 1795
	struct common_audit_data ad;

1796
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1797
	ad.u.path = *path;
1798
	__inode_security_revalidate(inode, path->dentry, true);
1799
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1800 1801
}

1802 1803 1804 1805 1806 1807 1808
/* 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;

1809 1810
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
1811
	return inode_has_perm(cred, file_inode(file), av, &ad);
1812 1813
}

L
Linus Torvalds 已提交
1814 1815 1816 1817 1818 1819 1820 1821
/* 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. */
1822 1823 1824
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1825 1826
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1827
	struct inode *inode = file_inode(file);
1828
	struct common_audit_data ad;
1829
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1830 1831
	int rc;

1832 1833
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
L
Linus Torvalds 已提交
1834

1835 1836
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1837 1838 1839 1840
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1841
			goto out;
L
Linus Torvalds 已提交
1842 1843 1844
	}

	/* av is zero if only checking access to the descriptor. */
1845
	rc = 0;
L
Linus Torvalds 已提交
1846
	if (av)
1847
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1848

1849 1850
out:
	return rc;
L
Linus Torvalds 已提交
1851 1852
}

1853 1854 1855
/*
 * Determine the label for an inode that might be unioned.
 */
1856 1857 1858 1859 1860
static int
selinux_determine_inode_label(const struct task_security_struct *tsec,
				 struct inode *dir,
				 const struct qstr *name, u16 tclass,
				 u32 *_new_isid)
1861 1862 1863 1864 1865 1866 1867 1868 1869 1870
{
	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 {
1871
		const struct inode_security_struct *dsec = inode_security(dir);
1872 1873 1874 1875 1876 1877 1878
		return security_transition_sid(tsec->sid, dsec->sid, tclass,
					       name, _new_isid);
	}

	return 0;
}

L
Linus Torvalds 已提交
1879 1880 1881 1882 1883
/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1884
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1885 1886
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1887
	u32 sid, newsid;
1888
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1889 1890
	int rc;

1891
	dsec = inode_security(dir);
L
Linus Torvalds 已提交
1892 1893
	sbsec = dir->i_sb->s_security;

1894 1895
	sid = tsec->sid;

1896
	ad.type = LSM_AUDIT_DATA_DENTRY;
1897
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1898

1899
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1900 1901 1902 1903 1904
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1905 1906
	rc = selinux_determine_inode_label(current_security(), dir,
					   &dentry->d_name, tclass, &newsid);
1907 1908
	if (rc)
		return rc;
L
Linus Torvalds 已提交
1909

1910
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1911 1912 1913 1914 1915 1916 1917 1918
	if (rc)
		return rc;

	return avc_has_perm(newsid, sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE, &ad);
}

1919 1920 1921
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1922 1923 1924 1925 1926 1927 1928 1929

/* 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;
1930
	struct common_audit_data ad;
1931
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1932 1933 1934
	u32 av;
	int rc;

1935 1936
	dsec = inode_security(dir);
	isec = backing_inode_security(dentry);
L
Linus Torvalds 已提交
1937

1938
	ad.type = LSM_AUDIT_DATA_DENTRY;
1939
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1940 1941 1942

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1943
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957
	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:
E
Eric Paris 已提交
1958 1959
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1960 1961 1962
		return 0;
	}

1963
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1964 1965 1966 1967 1968 1969 1970 1971 1972
	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;
1973
	struct common_audit_data ad;
1974
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1975 1976 1977 1978
	u32 av;
	int old_is_dir, new_is_dir;
	int rc;

1979 1980
	old_dsec = inode_security(old_dir);
	old_isec = backing_inode_security(old_dentry);
1981
	old_is_dir = d_is_dir(old_dentry);
1982
	new_dsec = inode_security(new_dir);
L
Linus Torvalds 已提交
1983

1984
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1985

1986
	ad.u.dentry = old_dentry;
1987
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1988 1989 1990
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1991
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1992 1993 1994 1995
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1996
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1997 1998 1999 2000 2001
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

2002
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
2003
	av = DIR__ADD_NAME | DIR__SEARCH;
2004
	if (d_is_positive(new_dentry))
L
Linus Torvalds 已提交
2005
		av |= DIR__REMOVE_NAME;
2006
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
2007 2008
	if (rc)
		return rc;
2009
	if (d_is_positive(new_dentry)) {
2010
		new_isec = backing_inode_security(new_dentry);
2011
		new_is_dir = d_is_dir(new_dentry);
2012
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
				  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. */
2023
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
2024 2025
			       struct super_block *sb,
			       u32 perms,
2026
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
2027 2028
{
	struct superblock_security_struct *sbsec;
2029
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
2030 2031

	sbsec = sb->s_security;
2032
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
2033 2034 2035 2036 2037 2038 2039
}

/* 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;

A
Al Viro 已提交
2040
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062
		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;
}

2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085
/* 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;
}

E
Eric Paris 已提交
2086
/*
2087
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
2088 2089
 * open permission.
 */
2090
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
2091
{
2092
	u32 av = file_to_av(file);
2093
	struct inode *inode = file_inode(file);
E
Eric Paris 已提交
2094

2095
	if (selinux_policycap_openperm && inode->i_sb->s_magic != SOCKFS_MAGIC)
2096 2097
		av |= FILE__OPEN;

E
Eric Paris 已提交
2098 2099 2100
	return av;
}

L
Linus Torvalds 已提交
2101 2102
/* Hook functions begin here. */

2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146
static int selinux_binder_set_context_mgr(struct task_struct *mgr)
{
	u32 mysid = current_sid();
	u32 mgrsid = task_sid(mgr);

	return avc_has_perm(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(mysid, fromsid, SECCLASS_BINDER,
				  BINDER__IMPERSONATE, NULL);
		if (rc)
			return rc;
	}

	return avc_has_perm(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(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;
2147
	struct dentry *dentry = file->f_path.dentry;
2148
	struct inode_security_struct *isec;
2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163
	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(sid, fsec->sid,
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
			return rc;
	}

2164
	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2165 2166
		return 0;

2167
	isec = backing_inode_security(dentry);
2168 2169 2170 2171
	return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
			    &ad);
}

2172
static int selinux_ptrace_access_check(struct task_struct *child,
2173
				     unsigned int mode)
L
Linus Torvalds 已提交
2174
{
2175 2176 2177 2178
	u32 sid = current_sid();
	u32 csid = task_sid(child);

	if (mode & PTRACE_MODE_READ)
2179
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2180

2181
	return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2182 2183 2184 2185
}

static int selinux_ptrace_traceme(struct task_struct *parent)
{
2186 2187
	return avc_has_perm(task_sid(parent), current_sid(), SECCLASS_PROCESS,
			    PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
2188 2189 2190
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2191
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
2192
{
2193 2194
	return avc_has_perm(current_sid(), task_sid(target), SECCLASS_PROCESS,
			    PROCESS__GETCAP, NULL);
L
Linus Torvalds 已提交
2195 2196
}

D
David Howells 已提交
2197 2198 2199 2200
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)
L
Linus Torvalds 已提交
2201
{
2202 2203
	return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
			    PROCESS__SETCAP, NULL);
L
Linus Torvalds 已提交
2204 2205
}

2206 2207 2208 2209 2210 2211 2212 2213 2214 2215
/*
 * (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.
 */

2216 2217
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
2218
{
2219
	return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
L
Linus Torvalds 已提交
2220 2221 2222 2223
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2224
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2225 2226 2227 2228 2229 2230
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2231 2232 2233 2234 2235
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2236
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2237 2238 2239 2240
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2241
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2242 2243 2244 2245
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2246 2247 2248 2249 2250 2251
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2252 2253
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2254
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2255 2256
}

2257
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2258 2259
{
	switch (type) {
2260 2261
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2262 2263
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2264 2265 2266 2267
	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:
2268 2269 2270
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
				    NULL);
L
Linus Torvalds 已提交
2271
	}
2272 2273 2274
	/* All other syslog types */
	return avc_has_perm(current_sid(), SECINITSID_KERNEL,
			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
L
Linus Torvalds 已提交
2275 2276 2277 2278 2279 2280 2281 2282 2283 2284
}

/*
 * 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.
 */
2285
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2286 2287 2288
{
	int rc, cap_sys_admin = 0;

C
Casey Schaufler 已提交
2289
	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2290
				 SECURITY_CAP_NOAUDIT, true);
L
Linus Torvalds 已提交
2291 2292 2293
	if (rc == 0)
		cap_sys_admin = 1;

C
Casey Schaufler 已提交
2294
	return cap_sys_admin;
L
Linus Torvalds 已提交
2295 2296 2297 2298
}

/* binprm security operations */

2299
static u32 ptrace_parent_sid(void)
2300 2301 2302 2303 2304
{
	u32 sid = 0;
	struct task_struct *tracer;

	rcu_read_lock();
2305
	tracer = ptrace_parent(current);
2306 2307 2308 2309 2310 2311 2312
	if (tracer)
		sid = task_sid(tracer);
	rcu_read_unlock();

	return sid;
}

2313 2314 2315 2316 2317
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);
2318
	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347
	int rc;

	if (!nnp && !nosuid)
		return 0; /* neither NNP nor nosuid */

	if (new_tsec->sid == old_tsec->sid)
		return 0; /* No change in credentials */

	/*
	 * The only transitions we permit under NNP or nosuid
	 * are 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(old_tsec->sid, new_tsec->sid);
	if (rc) {
		/*
		 * 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;
		else
			return -EACCES;
	}
	return 0;
}

2348
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2349
{
2350 2351
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2352
	struct inode_security_struct *isec;
2353
	struct common_audit_data ad;
A
Al Viro 已提交
2354
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2355 2356
	int rc;

2357 2358 2359
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2360 2361
		return 0;

2362 2363
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
2364
	isec = inode_security(inode);
L
Linus Torvalds 已提交
2365 2366

	/* Default to the current task SID. */
2367 2368
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2369

2370
	/* Reset fs, key, and sock SIDs on execve. */
2371 2372 2373
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2374

2375 2376
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2377
		/* Reset exec SID on execve. */
2378
		new_tsec->exec_sid = 0;
2379

2380 2381 2382 2383
		/* Fail on NNP or nosuid if not an allowed transition. */
		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
		if (rc)
			return rc;
L
Linus Torvalds 已提交
2384 2385
	} else {
		/* Check for a default transition on this program. */
2386
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2387 2388
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2389 2390
		if (rc)
			return rc;
2391 2392 2393 2394 2395 2396 2397 2398

		/*
		 * 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;
L
Linus Torvalds 已提交
2399 2400
	}

2401 2402
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = bprm->file;
L
Linus Torvalds 已提交
2403

2404 2405
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2406 2407 2408 2409 2410
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2411
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2412 2413 2414 2415
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2416
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2417 2418 2419 2420
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431
		/* Check for shared state */
		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
			rc = avc_has_perm(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 */
2432
		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2433
			u32 ptsid = ptrace_parent_sid();
2434 2435 2436 2437 2438 2439 2440 2441
			if (ptsid != 0) {
				rc = avc_has_perm(ptsid, new_tsec->sid,
						  SECCLASS_PROCESS,
						  PROCESS__PTRACE, NULL);
				if (rc)
					return -EPERM;
			}
		}
L
Linus Torvalds 已提交
2442

2443 2444
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2445 2446 2447 2448 2449
	}

	return 0;
}

2450
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2451
{
2452
	const struct task_security_struct *tsec = current_security();
2453
	u32 sid, osid;
L
Linus Torvalds 已提交
2454 2455
	int atsecure = 0;

2456 2457 2458 2459
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2460 2461 2462
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2463
		atsecure = avc_has_perm(osid, sid,
2464 2465
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2466 2467
	}

C
Casey Schaufler 已提交
2468
	return !!atsecure;
L
Linus Torvalds 已提交
2469 2470
}

A
Al Viro 已提交
2471 2472 2473 2474 2475
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;
}

L
Linus Torvalds 已提交
2476
/* Derived from fs/exec.c:flush_old_files. */
2477 2478
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2479 2480
{
	struct file *file, *devnull = NULL;
2481
	struct tty_struct *tty;
2482
	int drop_tty = 0;
A
Al Viro 已提交
2483
	unsigned n;
L
Linus Torvalds 已提交
2484

2485
	tty = get_current_tty();
L
Linus Torvalds 已提交
2486
	if (tty) {
P
Peter Hurley 已提交
2487
		spin_lock(&tty->files_lock);
2488
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2489
			struct tty_file_private *file_priv;
2490

L
Linus Torvalds 已提交
2491
			/* Revalidate access to controlling tty.
2492 2493 2494 2495
			   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. */
N
Nick Piggin 已提交
2496 2497 2498
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2499
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2500
				drop_tty = 1;
L
Linus Torvalds 已提交
2501
		}
P
Peter Hurley 已提交
2502
		spin_unlock(&tty->files_lock);
A
Alan Cox 已提交
2503
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2504
	}
2505 2506 2507
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2508 2509

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2510 2511 2512
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2513

A
Al Viro 已提交
2514
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2515 2516 2517 2518 2519 2520 2521
	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)
A
Al Viro 已提交
2522
		fput(devnull);
L
Linus Torvalds 已提交
2523 2524
}

2525 2526 2527 2528
/*
 * Prepare a process for imminent new credential changes due to exec
 */
static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2529
{
2530 2531 2532
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2533

2534 2535 2536
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2537

2538 2539
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2540

2541 2542
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2543

2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556
	/* 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(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
			  PROCESS__RLIMITINH, NULL);
	if (rc) {
2557 2558
		/* protect against do_prlimit() */
		task_lock(current);
2559 2560 2561 2562
		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);
L
Linus Torvalds 已提交
2563
		}
2564
		task_unlock(current);
2565 2566
		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2567 2568 2569 2570
	}
}

/*
2571 2572
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2573
 */
2574
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2575
{
2576
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2577
	struct itimerval itimer;
2578
	u32 osid, sid;
L
Linus Torvalds 已提交
2579 2580
	int rc, i;

2581 2582 2583 2584
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2585 2586
		return;

2587 2588 2589 2590 2591 2592 2593 2594
	/* 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(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
L
Linus Torvalds 已提交
2595
	if (rc) {
2596 2597 2598 2599 2600
		if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
			memset(&itimer, 0, sizeof itimer);
			for (i = 0; i < 3; i++)
				do_setitimer(i, &itimer, NULL);
		}
L
Linus Torvalds 已提交
2601
		spin_lock_irq(&current->sighand->siglock);
2602 2603 2604
		if (!fatal_signal_pending(current)) {
			flush_sigqueue(&current->pending);
			flush_sigqueue(&current->signal->shared_pending);
2605 2606
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
2607
			recalc_sigpending();
2608
		}
L
Linus Torvalds 已提交
2609 2610 2611
		spin_unlock_irq(&current->sighand->siglock);
	}

2612 2613
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2614
	read_lock(&tasklist_lock);
2615
	__wake_up_parent(current, current->real_parent);
2616
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640
}

/* 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)
{
2641 2642 2643
	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) ||
2644 2645
		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
L
Linus Torvalds 已提交
2646 2647 2648 2649 2650 2651 2652
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2653
	} else
L
Linus Torvalds 已提交
2654 2655 2656 2657 2658
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2659 2660
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2661 2662 2663 2664 2665 2666
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2667
	} else
2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679
		*first = 0;

	while (current_size < len) {
		if (*from != '"') {
			**to = *from;
			*to += 1;
		}
		from += 1;
		current_size += 1;
	}
}

2680
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2681 2682 2683 2684
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2685
	int open_quote = 0;
L
Linus Torvalds 已提交
2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700

	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 {
2701 2702 2703 2704
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2705 2706 2707
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2708
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2709 2710 2711 2712 2713 2714 2715
			else
				take_option(&nosec, in_curr, &fnosec, len);

			in_curr = in_end + 1;
		}
	} while (*in_end++);

2716
	strcpy(in_save, nosec_save);
2717
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2718 2719 2720 2721
out:
	return rc;
}

2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755
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;

2756
		if (flags[i] == SBLABEL_MNT)
2757
			continue;
2758
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2759
		if (rc) {
2760
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2761 2762
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776
			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;
2777
			root_isec = backing_inode_security(sb->s_root);
2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799

			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:
	printk(KERN_WARNING "SELinux: unable to change security options "
2800 2801
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2802 2803 2804
	goto out_free_opts;
}

2805
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2806
{
2807
	const struct cred *cred = current_cred();
2808
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2809 2810 2811 2812 2813 2814
	int rc;

	rc = superblock_doinit(sb, data);
	if (rc)
		return rc;

2815 2816 2817 2818
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2819
	ad.type = LSM_AUDIT_DATA_DENTRY;
2820
	ad.u.dentry = sb->s_root;
2821
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2822 2823
}

2824
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2825
{
2826
	const struct cred *cred = current_cred();
2827
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2828

2829
	ad.type = LSM_AUDIT_DATA_DENTRY;
2830
	ad.u.dentry = dentry->d_sb->s_root;
2831
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2832 2833
}

A
Al Viro 已提交
2834
static int selinux_mount(const char *dev_name,
A
Al Viro 已提交
2835
			 const struct path *path,
A
Al Viro 已提交
2836
			 const char *type,
2837 2838
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2839
{
2840
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2841 2842

	if (flags & MS_REMOUNT)
2843
		return superblock_has_perm(cred, path->dentry->d_sb,
2844
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2845
	else
E
Eric Paris 已提交
2846
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2847 2848 2849 2850
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2851
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2852

2853
	return superblock_has_perm(cred, mnt->mnt_sb,
2854
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868
}

/* 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);
}

2869
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
A
Al Viro 已提交
2870
					const struct qstr *name, void **ctx,
2871 2872 2873 2874 2875
					u32 *ctxlen)
{
	u32 newsid;
	int rc;

2876 2877
	rc = selinux_determine_inode_label(current_security(),
					   d_inode(dentry->d_parent), name,
2878 2879 2880 2881
					   inode_mode_to_security_class(mode),
					   &newsid);
	if (rc)
		return rc;
2882 2883 2884 2885

	return security_sid_to_context(newsid, (char **)ctx, ctxlen);
}

2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906
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;
}

2907
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2908 2909
				       const struct qstr *qstr,
				       const char **name,
2910
				       void **value, size_t *len)
2911
{
2912
	const struct task_security_struct *tsec = current_security();
2913
	struct superblock_security_struct *sbsec;
2914
	u32 sid, newsid, clen;
2915
	int rc;
2916
	char *context;
2917 2918 2919

	sbsec = dir->i_sb->s_security;

2920 2921 2922
	sid = tsec->sid;
	newsid = tsec->create_sid;

2923
	rc = selinux_determine_inode_label(current_security(),
2924 2925 2926 2927 2928
		dir, qstr,
		inode_mode_to_security_class(inode->i_mode),
		&newsid);
	if (rc)
		return rc;
2929

2930
	/* Possibly defer initialization to selinux_complete_init. */
2931
	if (sbsec->flags & SE_SBINITIALIZED) {
2932 2933 2934
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
2935
		isec->initialized = LABEL_INITIALIZED;
2936
	}
2937

2938
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2939 2940
		return -EOPNOTSUPP;

2941 2942
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2943

2944
	if (value && len) {
2945
		rc = security_sid_to_context_force(newsid, &context, &clen);
2946
		if (rc)
2947 2948 2949
			return rc;
		*value = context;
		*len = clen;
2950 2951 2952 2953 2954
	}

	return 0;
}

A
Al Viro 已提交
2955
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974
{
	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);
}

2975
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2976 2977 2978 2979 2980 2981 2982 2983 2984
{
	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);
}

A
Al Viro 已提交
2985
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2986 2987 2988 2989 2990
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2991
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2992 2993 2994 2995 2996 2997
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2998 2999
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3000
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
3001 3002
}

3003 3004
static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
				     bool rcu)
L
Linus Torvalds 已提交
3005
{
3006
	const struct cred *cred = current_cred();
3007 3008 3009
	struct common_audit_data ad;
	struct inode_security_struct *isec;
	u32 sid;
L
Linus Torvalds 已提交
3010

3011 3012 3013 3014 3015
	validate_creds(cred);

	ad.type = LSM_AUDIT_DATA_DENTRY;
	ad.u.dentry = dentry;
	sid = cred_sid(cred);
3016 3017 3018
	isec = inode_security_rcu(inode, rcu);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
3019 3020 3021

	return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
				  rcu ? MAY_NOT_BLOCK : 0);
L
Linus Torvalds 已提交
3022 3023
}

3024 3025
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
3026
					   int result,
3027
					   unsigned flags)
L
Linus Torvalds 已提交
3028
{
3029
	struct common_audit_data ad;
3030 3031 3032
	struct inode_security_struct *isec = inode->i_security;
	int rc;

3033
	ad.type = LSM_AUDIT_DATA_INODE;
3034 3035 3036
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3037
			    audited, denied, result, &ad, flags);
3038 3039 3040 3041 3042
	if (rc)
		return rc;
	return 0;
}

3043
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
3044
{
3045
	const struct cred *cred = current_cred();
3046 3047
	u32 perms;
	bool from_access;
3048
	unsigned flags = mask & MAY_NOT_BLOCK;
3049 3050 3051 3052 3053
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
3054

3055
	from_access = mask & MAY_ACCESS;
3056 3057
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

3058 3059
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
3060 3061
		return 0;

3062
	validate_creds(cred);
3063

3064 3065
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
3066 3067 3068

	perms = file_mask_to_av(inode->i_mode, mask);

3069
	sid = cred_sid(cred);
3070 3071 3072
	isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
3073 3074 3075 3076 3077 3078 3079 3080

	rc = avc_has_perm_noaudit(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;

3081
	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3082 3083 3084
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
3085 3086 3087 3088
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
3089
	const struct cred *cred = current_cred();
3090
	struct inode *inode = d_backing_inode(dentry);
3091
	unsigned int ia_valid = iattr->ia_valid;
3092
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
3093

3094 3095 3096 3097 3098 3099 3100
	/* 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;
	}
L
Linus Torvalds 已提交
3101

3102 3103
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
3104
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
3105

3106 3107 3108 3109
	if (selinux_policycap_openperm &&
	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
	    (ia_valid & ATTR_SIZE) &&
	    !(ia_valid & ATTR_FILE))
3110 3111 3112
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
3113 3114
}

3115
static int selinux_inode_getattr(const struct path *path)
L
Linus Torvalds 已提交
3116
{
3117
	return path_has_perm(current_cred(), path, FILE__GETATTR);
L
Linus Torvalds 已提交
3118 3119
}

3120
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3121
{
3122 3123
	const struct cred *cred = current_cred();

3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137
	if (!strncmp(name, XATTR_SECURITY_PREFIX,
		     sizeof XATTR_SECURITY_PREFIX - 1)) {
		if (!strcmp(name, XATTR_NAME_CAPS)) {
			if (!capable(CAP_SETFCAP))
				return -EPERM;
		} else if (!capable(CAP_SYS_ADMIN)) {
			/* A different attribute in the security namespace.
			   Restrict to administrator. */
			return -EPERM;
		}
	}

	/* Not an attribute we recognize, so just check the
	   ordinary setattr permission. */
E
Eric Paris 已提交
3138
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
3139 3140
}

3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152
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;
}

3153 3154
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
				  const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3155
{
3156
	struct inode *inode = d_backing_inode(dentry);
3157
	struct inode_security_struct *isec;
L
Linus Torvalds 已提交
3158
	struct superblock_security_struct *sbsec;
3159
	struct common_audit_data ad;
3160
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
3161 3162
	int rc = 0;

3163 3164
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3165 3166

	sbsec = inode->i_sb->s_security;
3167
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
3168 3169
		return -EOPNOTSUPP;

3170
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
3171 3172
		return -EPERM;

3173
	ad.type = LSM_AUDIT_DATA_DENTRY;
3174
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
3175

3176
	isec = backing_inode_security(dentry);
3177
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
3178 3179 3180 3181
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

3182
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3183
	if (rc == -EINVAL) {
3184
		if (!has_cap_mac_admin(true)) {
3185 3186 3187 3188 3189 3190
			struct audit_buffer *ab;
			size_t audit_size;
			const char *str;

			/* We strip a nul only if it is at the end, otherwise the
			 * context contains a nul and we should audit that */
3191 3192 3193 3194 3195 3196 3197 3198 3199 3200
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
3201 3202 3203 3204 3205
			ab = audit_log_start(current->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);

3206
			return rc;
3207
		}
3208 3209
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
3210 3211 3212
	if (rc)
		return rc;

3213
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
3214 3215 3216 3217
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

3218
	rc = security_validate_transition(isec->sid, newsid, sid,
3219
					  isec->sclass);
L
Linus Torvalds 已提交
3220 3221 3222 3223 3224 3225 3226 3227 3228 3229
	if (rc)
		return rc;

	return avc_has_perm(newsid,
			    sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE,
			    &ad);
}

3230
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3231
					const void *value, size_t size,
3232
					int flags)
L
Linus Torvalds 已提交
3233
{
3234
	struct inode *inode = d_backing_inode(dentry);
3235
	struct inode_security_struct *isec;
L
Linus Torvalds 已提交
3236 3237 3238 3239 3240 3241 3242 3243
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_NAME_SELINUX)) {
		/* Not an attribute we recognize, so nothing to do. */
		return;
	}

3244
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
3245
	if (rc) {
3246 3247 3248
		printk(KERN_ERR "SELinux:  unable to map context to SID"
		       "for (%s, %lu), rc=%d\n",
		       inode->i_sb->s_id, inode->i_ino, -rc);
L
Linus Torvalds 已提交
3249 3250 3251
		return;
	}

3252
	isec = backing_inode_security(dentry);
3253
	spin_lock(&isec->lock);
3254
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3255
	isec->sid = newsid;
3256
	isec->initialized = LABEL_INITIALIZED;
3257
	spin_unlock(&isec->lock);
3258

L
Linus Torvalds 已提交
3259 3260 3261
	return;
}

3262
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3263
{
3264 3265
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3266
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3267 3268
}

3269
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
3270
{
3271 3272
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3273
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3274 3275
}

3276
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3277
{
3278 3279
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3280 3281 3282 3283 3284 3285

	/* No one is allowed to remove a SELinux security label.
	   You can change the label, but all data must be labeled. */
	return -EACCES;
}

3286
/*
3287
 * Copy the inode security context value to the user.
3288 3289 3290
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
3291
static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
3292
{
3293 3294 3295
	u32 size;
	int error;
	char *context = NULL;
3296
	struct inode_security_struct *isec;
3297

3298 3299
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3300

3301 3302 3303 3304 3305 3306 3307 3308 3309
	/*
	 * 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.
	 */
3310
	isec = inode_security(inode);
3311
	if (has_cap_mac_admin(false))
3312 3313 3314 3315
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3316 3317 3318 3319 3320 3321 3322 3323 3324 3325
	if (error)
		return error;
	error = size;
	if (alloc) {
		*buffer = context;
		goto out_nofree;
	}
	kfree(context);
out_nofree:
	return error;
L
Linus Torvalds 已提交
3326 3327 3328
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3329
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3330
{
3331
	struct inode_security_struct *isec = inode_security_novalidate(inode);
L
Linus Torvalds 已提交
3332 3333 3334 3335 3336 3337 3338 3339 3340
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;

	if (!value || !size)
		return -EACCES;

3341
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
L
Linus Torvalds 已提交
3342 3343 3344
	if (rc)
		return rc;

3345
	spin_lock(&isec->lock);
3346
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3347
	isec->sid = newsid;
3348
	isec->initialized = LABEL_INITIALIZED;
3349
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360
	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;
}

3361
static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3362
{
3363
	struct inode_security_struct *isec = inode_security_novalidate(inode);
3364 3365 3366
	*secid = isec->sid;
}

3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386
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;
}

3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401
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;
}

L
Linus Torvalds 已提交
3402 3403
/* file security operations */

3404
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3405
{
3406
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3407
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3408 3409 3410 3411 3412

	/* 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;

3413 3414
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3415 3416
}

3417 3418
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3419
	struct inode *inode = file_inode(file);
3420
	struct file_security_struct *fsec = file->f_security;
3421
	struct inode_security_struct *isec;
3422 3423
	u32 sid = current_sid();

3424
	if (!mask)
3425 3426 3427
		/* No permission to check.  Existence test. */
		return 0;

3428
	isec = inode_security(inode);
3429 3430
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3431
		/* No change since file_open check. */
3432 3433
		return 0;

3434 3435 3436
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3437 3438 3439 3440 3441 3442 3443 3444 3445 3446
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);
}

3447 3448 3449 3450
/*
 * Check whether a task has the ioctl permission and cmd
 * operation to an inode.
 */
3451
static int ioctl_has_perm(const struct cred *cred, struct file *file,
3452 3453 3454 3455 3456
		u32 requested, u16 cmd)
{
	struct common_audit_data ad;
	struct file_security_struct *fsec = file->f_security;
	struct inode *inode = file_inode(file);
3457
	struct inode_security_struct *isec;
3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480
	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(ssid, fsec->sid,
				SECCLASS_FD,
				FD__USE,
				&ad);
		if (rc)
			goto out;
	}

	if (unlikely(IS_PRIVATE(inode)))
		return 0;

3481
	isec = inode_security(inode);
3482 3483 3484 3485 3486 3487
	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
			requested, driver, xperm, &ad);
out:
	return rc;
}

L
Linus Torvalds 已提交
3488 3489 3490
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3491
	const struct cred *cred = current_cred();
3492
	int error = 0;
L
Linus Torvalds 已提交
3493

3494 3495 3496 3497 3498 3499 3500
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3501
	case FS_IOC_GETFLAGS:
3502
	/* fall through */
3503
	case FS_IOC_GETVERSION:
3504 3505
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3506

3507
	case FS_IOC_SETFLAGS:
3508
	/* fall through */
3509
	case FS_IOC_SETVERSION:
3510 3511 3512 3513 3514 3515 3516 3517 3518
		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;
L
Linus Torvalds 已提交
3519

3520 3521
	case KDSKBENT:
	case KDSKBSENT:
3522
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3523
					    SECURITY_CAP_AUDIT, true);
3524 3525 3526 3527 3528 3529
		break;

	/* default case assumes that the command will go
	 * to the file's ioctl() function.
	 */
	default:
3530
		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3531 3532
	}
	return error;
L
Linus Torvalds 已提交
3533 3534
}

3535 3536
static int default_noexec;

L
Linus Torvalds 已提交
3537 3538
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3539
	const struct cred *cred = current_cred();
3540
	u32 sid = cred_sid(cred);
D
David Howells 已提交
3541
	int rc = 0;
3542

3543
	if (default_noexec &&
3544 3545
	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
				   (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3546 3547 3548 3549 3550
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
3551 3552
		rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
				  PROCESS__EXECMEM, NULL);
L
Linus Torvalds 已提交
3553
		if (rc)
D
David Howells 已提交
3554
			goto error;
L
Linus Torvalds 已提交
3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567
	}

	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;

3568
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3569
	}
D
David Howells 已提交
3570 3571 3572

error:
	return rc;
L
Linus Torvalds 已提交
3573 3574
}

3575
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3576
{
C
Casey Schaufler 已提交
3577
	int rc = 0;
L
Linus Torvalds 已提交
3578

3579
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3580
		u32 sid = current_sid();
3581 3582
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3583 3584
	}

3585
	return rc;
3586
}
L
Linus Torvalds 已提交
3587

3588 3589 3590
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602
	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;
	}

L
Linus Torvalds 已提交
3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613
	if (selinux_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)
{
3614
	const struct cred *cred = current_cred();
3615
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
3616 3617 3618 3619

	if (selinux_checkreqprot)
		prot = reqprot;

3620 3621
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3622
		int rc = 0;
3623 3624
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
3625 3626
			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
					  PROCESS__EXECHEAP, NULL);
3627
		} else if (!vma->vm_file &&
3628 3629
			   ((vma->vm_start <= vma->vm_mm->start_stack &&
			     vma->vm_end >= vma->vm_mm->start_stack) ||
3630
			    vma_is_stack_for_current(vma))) {
3631 3632
			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
					  PROCESS__EXECSTACK, NULL);
3633 3634 3635 3636 3637 3638 3639 3640
		} 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.
			 */
D
David Howells 已提交
3641
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3642
		}
3643 3644 3645
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3646 3647 3648 3649 3650 3651

	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)
{
3652 3653 3654
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3655 3656 3657 3658 3659
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3660
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3661 3662 3663
	int err = 0;

	switch (cmd) {
3664 3665
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3666
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3667
			break;
3668 3669 3670 3671 3672 3673 3674
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3675
	case F_GETOWNER_UIDS:
3676
		/* Just check FD__USE permission */
3677
		err = file_has_perm(cred, file, 0);
3678 3679 3680 3681
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
3682 3683 3684
	case F_OFD_GETLK:
	case F_OFD_SETLK:
	case F_OFD_SETLKW:
L
Linus Torvalds 已提交
3685
#if BITS_PER_LONG == 32
3686 3687 3688
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3689
#endif
3690
		err = file_has_perm(cred, file, FILE__LOCK);
3691
		break;
L
Linus Torvalds 已提交
3692 3693 3694 3695 3696
	}

	return err;
}

3697
static void selinux_file_set_fowner(struct file *file)
L
Linus Torvalds 已提交
3698 3699 3700 3701
{
	struct file_security_struct *fsec;

	fsec = file->f_security;
3702
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3703 3704 3705 3706 3707
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3708
	struct file *file;
3709
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3710 3711 3712 3713
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3714
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3715 3716 3717 3718 3719 3720 3721 3722

	fsec = file->f_security;

	if (!signum)
		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
	else
		perm = signal_to_av(signum);

3723
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3724 3725 3726 3727 3728
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3729 3730 3731
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3732 3733
}

3734
static int selinux_file_open(struct file *file, const struct cred *cred)
3735 3736 3737
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3738

3739
	fsec = file->f_security;
3740
	isec = inode_security(file_inode(file));
3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757
	/*
	 * 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();
	/*
	 * 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.
	 */
3758
	return file_path_has_perm(cred, file, open_file_to_av(file));
3759 3760
}

L
Linus Torvalds 已提交
3761 3762
/* task security operations */

3763 3764
static int selinux_task_alloc(struct task_struct *task,
			      unsigned long clone_flags)
L
Linus Torvalds 已提交
3765
{
3766 3767 3768
	u32 sid = current_sid();

	return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
L
Linus Torvalds 已提交
3769 3770
}

3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785
/*
 * 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;
}

D
David Howells 已提交
3786 3787 3788 3789
/*
 * detach and free the LSM part of a set of credentials
 */
static void selinux_cred_free(struct cred *cred)
L
Linus Torvalds 已提交
3790
{
D
David Howells 已提交
3791
	struct task_security_struct *tsec = cred->security;
3792

3793 3794 3795 3796 3797
	/*
	 * 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);
3798
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3799 3800
	kfree(tsec);
}
L
Linus Torvalds 已提交
3801

D
David Howells 已提交
3802 3803 3804 3805 3806 3807 3808 3809
/*
 * 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;
L
Linus Torvalds 已提交
3810

D
David Howells 已提交
3811
	old_tsec = old->security;
L
Linus Torvalds 已提交
3812

D
David Howells 已提交
3813 3814 3815
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3816

D
David Howells 已提交
3817
	new->security = tsec;
L
Linus Torvalds 已提交
3818 3819 3820
	return 0;
}

3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831
/*
 * 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;
}

3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860
/*
 * 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(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)
{
3861
	struct inode_security_struct *isec = inode_security(inode);
3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

	ret = avc_has_perm(sid, isec->sid,
			   SECCLASS_KERNEL_SERVICE,
			   KERNEL_SERVICE__CREATE_FILES_AS,
			   NULL);

	if (ret == 0)
		tsec->create_sid = isec->sid;
3873
	return ret;
3874 3875
}

3876
static int selinux_kernel_module_request(char *kmod_name)
3877
{
3878 3879
	struct common_audit_data ad;

3880
	ad.type = LSM_AUDIT_DATA_KMOD;
3881 3882
	ad.u.kmod_name = kmod_name;

3883
	return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3884
			    SYSTEM__MODULE_REQUEST, &ad);
3885 3886
}

3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900
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(sid, sid, SECCLASS_SYSTEM,
					SYSTEM__MODULE_LOAD, NULL);

	/* finit_module */
3901

3902 3903
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
3904 3905 3906 3907 3908 3909 3910 3911

	fsec = file->f_security;
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
		if (rc)
			return rc;
	}

3912
	isec = inode_security(file_inode(file));
3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932
	return avc_has_perm(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;
}

L
Linus Torvalds 已提交
3933 3934
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3935 3936
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETPGID, NULL);
L
Linus Torvalds 已提交
3937 3938 3939 3940
}

static int selinux_task_getpgid(struct task_struct *p)
{
3941 3942
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETPGID, NULL);
L
Linus Torvalds 已提交
3943 3944 3945 3946
}

static int selinux_task_getsid(struct task_struct *p)
{
3947 3948
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSESSION, NULL);
L
Linus Torvalds 已提交
3949 3950
}

3951 3952
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3953
	*secid = task_sid(p);
3954 3955
}

L
Linus Torvalds 已提交
3956 3957
static int selinux_task_setnice(struct task_struct *p, int nice)
{
3958 3959
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
L
Linus Torvalds 已提交
3960 3961
}

3962 3963
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3964 3965
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
3966 3967
}

3968 3969
static int selinux_task_getioprio(struct task_struct *p)
{
3970 3971
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSCHED, NULL);
3972 3973
}

3974 3975 3976 3977 3978
int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
			 unsigned int flags)
{
	u32 av = 0;

3979 3980
	if (!flags)
		return 0;
3981 3982 3983 3984 3985 3986 3987 3988
	if (flags & LSM_PRLIMIT_WRITE)
		av |= PROCESS__SETRLIMIT;
	if (flags & LSM_PRLIMIT_READ)
		av |= PROCESS__GETRLIMIT;
	return avc_has_perm(cred_sid(cred), cred_sid(tcred),
			    SECCLASS_PROCESS, av, NULL);
}

3989 3990
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3991
{
3992
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3993 3994 3995 3996

	/* 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
D
David Howells 已提交
3997
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3998
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3999 4000
		return avc_has_perm(current_sid(), task_sid(p),
				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
L
Linus Torvalds 已提交
4001 4002 4003 4004

	return 0;
}

4005
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
4006
{
4007 4008
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
L
Linus Torvalds 已提交
4009 4010 4011 4012
}

static int selinux_task_getscheduler(struct task_struct *p)
{
4013 4014
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSCHED, NULL);
L
Linus Torvalds 已提交
4015 4016
}

4017 4018
static int selinux_task_movememory(struct task_struct *p)
{
4019 4020
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
4021 4022
}

4023 4024
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
4025 4026 4027 4028 4029 4030 4031
{
	u32 perm;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
4032 4033 4034
	if (!secid)
		secid = current_sid();
	return avc_has_perm(secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
L
Linus Torvalds 已提交
4035 4036 4037 4038 4039 4040
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
4041
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
4042

4043
	spin_lock(&isec->lock);
4044
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4045
	isec->sid = sid;
4046
	isec->initialized = LABEL_INITIALIZED;
4047
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
4048 4049 4050
}

/* Returns error only if unable to parse addresses */
4051
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4052
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
4053 4054 4055 4056
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

4057
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
4058 4059 4060 4061 4062 4063 4064 4065
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

	ihlen = ih->ihl * 4;
	if (ihlen < sizeof(_iph))
		goto out;

4066 4067
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
4068 4069
	ret = 0;

4070 4071 4072
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
4073
	switch (ih->protocol) {
4074 4075
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
4076

4077 4078
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
4079 4080 4081 4082 4083 4084

		offset += ihlen;
		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

4085 4086
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
4087
		break;
4088 4089 4090 4091 4092 4093 4094 4095
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

L
Linus Torvalds 已提交
4096
		offset += ihlen;
4097
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
4098
		if (uh == NULL)
4099
			break;
L
Linus Torvalds 已提交
4100

4101 4102
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
4103 4104
		break;
	}
L
Linus Torvalds 已提交
4105

J
James Morris 已提交
4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116
	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;

4117 4118
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
4119
		break;
4120
	}
J
James Morris 已提交
4121

4122 4123 4124
	default:
		break;
	}
L
Linus Torvalds 已提交
4125 4126 4127 4128
out:
	return ret;
}

4129
#if IS_ENABLED(CONFIG_IPV6)
L
Linus Torvalds 已提交
4130 4131

/* Returns error only if unable to parse addresses */
4132
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4133
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
4134 4135 4136 4137
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
4138
	__be16 frag_off;
L
Linus Torvalds 已提交
4139

4140
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
4141 4142 4143 4144
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

4145 4146
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
4147 4148 4149 4150
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
4151
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
4152 4153 4154
	if (offset < 0)
		goto out;

4155 4156 4157
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
4158 4159
	switch (nexthdr) {
	case IPPROTO_TCP: {
4160
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
4161 4162 4163 4164 4165

		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

4166 4167
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
4168 4169 4170 4171 4172 4173 4174 4175 4176 4177
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
		if (uh == NULL)
			break;

4178 4179
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
4180 4181 4182
		break;
	}

J
James Morris 已提交
4183 4184 4185 4186 4187 4188 4189
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh == NULL)
			break;

4190 4191
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
4192
		break;
4193
	}
J
James Morris 已提交
4194

L
Linus Torvalds 已提交
4195 4196 4197 4198 4199 4200 4201 4202 4203 4204
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

4205
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4206
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
4207
{
4208 4209
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
4210

4211
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
4212
	case PF_INET:
4213
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4214 4215
		if (ret)
			goto parse_error;
4216 4217
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
4218
		goto okay;
L
Linus Torvalds 已提交
4219

4220
#if IS_ENABLED(CONFIG_IPV6)
L
Linus Torvalds 已提交
4221
	case PF_INET6:
4222
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4223 4224
		if (ret)
			goto parse_error;
4225 4226
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
4227
		goto okay;
L
Linus Torvalds 已提交
4228 4229
#endif	/* IPV6 */
	default:
4230 4231
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
4232 4233
	}

4234 4235 4236 4237
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
4238
	return ret;
4239 4240 4241 4242 4243

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
4244 4245
}

4246
/**
4247
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4248
 * @skb: the packet
4249
 * @family: protocol family
4250
 * @sid: the packet's peer label SID
4251 4252
 *
 * Description:
4253 4254 4255 4256 4257 4258
 * 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.
4259 4260
 *
 */
4261
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4262
{
4263
	int err;
4264 4265
	u32 xfrm_sid;
	u32 nlbl_sid;
4266
	u32 nlbl_type;
4267

4268
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4269 4270 4271 4272 4273
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
4274

4275 4276 4277 4278 4279
	err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
		       " unable to determine packet's peer label\n");
4280
		return -EACCES;
4281
	}
4282 4283

	return 0;
4284 4285
}

4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308 4309
/**
 * 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(sk_sid, skb_sid, conn_sid);
	else
		*conn_sid = sk_sid;

	return err;
}

L
Linus Torvalds 已提交
4310
/* socket security operations */
4311

4312 4313
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
4314
{
4315 4316 4317 4318 4319 4320 4321
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
4322 4323
}

4324
static int sock_has_perm(struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
4325
{
4326
	struct sk_security_struct *sksec = sk->sk_security;
4327
	struct common_audit_data ad;
4328
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4329

4330 4331
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
4332

4333
	ad.type = LSM_AUDIT_DATA_NET;
4334 4335
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
4336

4337 4338
	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
			    &ad);
L
Linus Torvalds 已提交
4339 4340 4341 4342 4343
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
4344
	const struct task_security_struct *tsec = current_security();
4345
	u32 newsid;
4346
	u16 secclass;
4347
	int rc;
L
Linus Torvalds 已提交
4348 4349

	if (kern)
4350
		return 0;
4351 4352

	secclass = socket_type_to_security_class(family, type, protocol);
4353 4354 4355 4356
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

4357
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
4358 4359
}

V
Venkat Yekkirala 已提交
4360 4361
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
4362
{
4363
	const struct task_security_struct *tsec = current_security();
4364
	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4365
	struct sk_security_struct *sksec;
4366 4367
	u16 sclass = socket_type_to_security_class(family, type, protocol);
	u32 sid = SECINITSID_KERNEL;
4368 4369
	int err = 0;

4370 4371
	if (!kern) {
		err = socket_sockcreate_sid(tsec, sclass, &sid);
4372 4373 4374
		if (err)
			return err;
	}
4375

4376 4377
	isec->sclass = sclass;
	isec->sid = sid;
4378
	isec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4379

4380 4381
	if (sock->sk) {
		sksec = sock->sk->sk_security;
4382 4383
		sksec->sclass = sclass;
		sksec->sid = sid;
4384
		err = selinux_netlbl_socket_post_create(sock->sk, family);
4385 4386
	}

V
Venkat Yekkirala 已提交
4387
	return err;
L
Linus Torvalds 已提交
4388 4389 4390 4391 4392 4393 4394 4395
}

/* 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)
{
4396
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
4397 4398 4399
	u16 family;
	int err;

4400
	err = sock_has_perm(sk, SOCKET__BIND);
L
Linus Torvalds 已提交
4401 4402 4403 4404 4405
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
4406 4407
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
4408
	 */
4409
	family = sk->sk_family;
L
Linus Torvalds 已提交
4410 4411
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
4412
		struct sk_security_struct *sksec = sk->sk_security;
4413
		struct common_audit_data ad;
4414
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4415 4416 4417
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
4418
		u32 sid, node_perm;
L
Linus Torvalds 已提交
4419 4420

		if (family == PF_INET) {
4421 4422 4423 4424
			if (addrlen < sizeof(struct sockaddr_in)) {
				err = -EINVAL;
				goto out;
			}
L
Linus Torvalds 已提交
4425 4426 4427 4428
			addr4 = (struct sockaddr_in *)address;
			snum = ntohs(addr4->sin_port);
			addrp = (char *)&addr4->sin_addr.s_addr;
		} else {
4429 4430 4431 4432
			if (addrlen < SIN6_LEN_RFC2133) {
				err = -EINVAL;
				goto out;
			}
L
Linus Torvalds 已提交
4433 4434 4435 4436 4437
			addr6 = (struct sockaddr_in6 *)address;
			snum = ntohs(addr6->sin6_port);
			addrp = (char *)&addr6->sin6_addr.s6_addr;
		}

4438 4439 4440
		if (snum) {
			int low, high;

4441
			inet_get_local_port_range(sock_net(sk), &low, &high);
4442

4443 4444
			if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
			    snum > high) {
P
Paul Moore 已提交
4445 4446
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4447 4448
				if (err)
					goto out;
4449
				ad.type = LSM_AUDIT_DATA_NET;
4450 4451 4452
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4453 4454
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4455 4456 4457 4458
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4459
		}
4460

4461
		switch (sksec->sclass) {
4462
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4463 4464
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4465

4466
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4467 4468
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4469 4470 4471 4472 4473

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4474 4475 4476 4477
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4478

4479
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4480 4481
		if (err)
			goto out;
4482

4483
		ad.type = LSM_AUDIT_DATA_NET;
4484 4485 4486
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4487 4488

		if (family == PF_INET)
4489
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4490
		else
4491
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4492

4493 4494
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4495 4496 4497 4498 4499 4500 4501 4502 4503
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4504
	struct sock *sk = sock->sk;
4505
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4506 4507
	int err;

4508
	err = sock_has_perm(sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4509 4510 4511 4512
	if (err)
		return err;

	/*
J
James Morris 已提交
4513
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4514
	 */
4515 4516
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4517
		struct common_audit_data ad;
4518
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4519 4520 4521
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4522
		u32 sid, perm;
L
Linus Torvalds 已提交
4523 4524 4525

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4526
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4527 4528 4529 4530
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4531
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4532 4533 4534 4535
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4536
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4537 4538 4539
		if (err)
			goto out;

4540
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4541 4542
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4543
		ad.type = LSM_AUDIT_DATA_NET;
4544 4545 4546
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4547
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4548 4549 4550 4551
		if (err)
			goto out;
	}

4552 4553
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4554 4555 4556 4557 4558 4559
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4560
	return sock_has_perm(sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4561 4562 4563 4564 4565 4566 4567
}

static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
{
	int err;
	struct inode_security_struct *isec;
	struct inode_security_struct *newisec;
4568 4569
	u16 sclass;
	u32 sid;
L
Linus Torvalds 已提交
4570

4571
	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4572 4573 4574
	if (err)
		return err;

4575
	isec = inode_security_novalidate(SOCK_INODE(sock));
4576 4577 4578 4579 4580 4581 4582 4583
	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;
4584
	newisec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4585 4586 4587 4588 4589

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4590
				  int size)
L
Linus Torvalds 已提交
4591
{
4592
	return sock_has_perm(sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4593 4594 4595 4596 4597
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4598
	return sock_has_perm(sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4599 4600 4601 4602
}

static int selinux_socket_getsockname(struct socket *sock)
{
4603
	return sock_has_perm(sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4604 4605 4606 4607
}

static int selinux_socket_getpeername(struct socket *sock)
{
4608
	return sock_has_perm(sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4609 4610
}

4611
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4612
{
4613 4614
	int err;

4615
	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4616 4617 4618 4619
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4620 4621 4622 4623 4624
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4625
	return sock_has_perm(sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4626 4627 4628 4629
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4630
	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4631 4632
}

4633 4634
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4635 4636
					      struct sock *newsk)
{
4637 4638
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4639
	struct sk_security_struct *sksec_new = newsk->sk_security;
4640
	struct common_audit_data ad;
4641
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4642 4643
	int err;

4644
	ad.type = LSM_AUDIT_DATA_NET;
4645 4646
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4647

4648 4649
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4650 4651 4652 4653 4654
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4655 4656 4657 4658 4659
	sksec_new->peer_sid = sksec_sock->sid;
	err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
				    &sksec_new->sid);
	if (err)
		return err;
4660

4661 4662 4663 4664
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4665 4666 4667 4668 4669
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4670 4671
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4672
	struct common_audit_data ad;
4673
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4674

4675
	ad.type = LSM_AUDIT_DATA_NET;
4676 4677
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4678

4679 4680
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4681 4682
}

4683 4684
static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
				    char *addrp, u16 family, u32 peer_sid,
4685
				    struct common_audit_data *ad)
4686 4687 4688 4689 4690
{
	int err;
	u32 if_sid;
	u32 node_sid;

4691
	err = sel_netif_sid(ns, ifindex, &if_sid);
4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705
	if (err)
		return err;
	err = avc_has_perm(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(peer_sid, node_sid,
			    SECCLASS_NODE, NODE__RECVFROM, ad);
}

4706
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4707
				       u16 family)
4708
{
4709
	int err = 0;
4710 4711
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4712
	struct common_audit_data ad;
4713
	struct lsm_network_audit net = {0,};
4714 4715
	char *addrp;

4716
	ad.type = LSM_AUDIT_DATA_NET;
4717 4718 4719
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4720 4721 4722
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4723

4724
	if (selinux_secmark_enabled()) {
4725
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4726
				   PACKET__RECV, &ad);
4727 4728 4729
		if (err)
			return err;
	}
4730

4731 4732 4733 4734
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4735

4736 4737 4738 4739 4740
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4741
	int err;
4742
	struct sk_security_struct *sksec = sk->sk_security;
4743 4744
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4745
	struct common_audit_data ad;
4746
	struct lsm_network_audit net = {0,};
4747
	char *addrp;
4748 4749
	u8 secmark_active;
	u8 peerlbl_active;
4750 4751

	if (family != PF_INET && family != PF_INET6)
4752
		return 0;
4753 4754

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4755
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4756 4757
		family = PF_INET;

4758 4759 4760 4761
	/* 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. */
4762
	if (!selinux_policycap_netpeer)
4763 4764 4765
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4766
	peerlbl_active = selinux_peerlbl_enabled();
4767 4768 4769
	if (!secmark_active && !peerlbl_active)
		return 0;

4770
	ad.type = LSM_AUDIT_DATA_NET;
4771 4772 4773
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4774
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4775
	if (err)
4776
		return err;
4777

4778
	if (peerlbl_active) {
4779 4780 4781
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4782 4783
		if (err)
			return err;
4784 4785
		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
					       addrp, family, peer_sid, &ad);
4786
		if (err) {
4787
			selinux_netlbl_err(skb, family, err, 0);
4788
			return err;
4789
		}
4790 4791
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4792
		if (err) {
4793
			selinux_netlbl_err(skb, family, err, 0);
C
Chad Hanson 已提交
4794 4795
			return err;
		}
4796 4797
	}

4798
	if (secmark_active) {
4799 4800 4801 4802 4803 4804
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4805
	return err;
L
Linus Torvalds 已提交
4806 4807
}

C
Catherine Zhang 已提交
4808 4809
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4810 4811 4812 4813
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4814
	struct sk_security_struct *sksec = sock->sk->sk_security;
4815
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4816

4817 4818
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4819
		peer_sid = sksec->peer_sid;
4820 4821
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4822

C
Catherine Zhang 已提交
4823
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4824
	if (err)
4825
		return err;
L
Linus Torvalds 已提交
4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841

	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;
}

4842
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4843
{
4844
	u32 peer_secid = SECSID_NULL;
4845
	u16 family;
4846
	struct inode_security_struct *isec;
C
Catherine Zhang 已提交
4847

4848 4849 4850 4851 4852
	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)
4853 4854 4855 4856
		family = sock->sk->sk_family;
	else
		goto out;

4857 4858 4859 4860
	if (sock && family == PF_UNIX) {
		isec = inode_security_novalidate(SOCK_INODE(sock));
		peer_secid = isec->sid;
	} else if (skb)
4861
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4862

4863
out:
4864
	*secid = peer_secid;
4865 4866 4867
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4868 4869
}

A
Al Viro 已提交
4870
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4871
{
4872 4873 4874 4875 4876 4877 4878 4879
	struct sk_security_struct *sksec;

	sksec = kzalloc(sizeof(*sksec), priority);
	if (!sksec)
		return -ENOMEM;

	sksec->peer_sid = SECINITSID_UNLABELED;
	sksec->sid = SECINITSID_UNLABELED;
4880
	sksec->sclass = SECCLASS_SOCKET;
4881 4882 4883 4884
	selinux_netlbl_sk_security_reset(sksec);
	sk->sk_security = sksec;

	return 0;
L
Linus Torvalds 已提交
4885 4886 4887 4888
}

static void selinux_sk_free_security(struct sock *sk)
{
4889 4890 4891 4892 4893
	struct sk_security_struct *sksec = sk->sk_security;

	sk->sk_security = NULL;
	selinux_netlbl_sk_security_free(sksec);
	kfree(sksec);
L
Linus Torvalds 已提交
4894 4895
}

4896
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4897
{
4898 4899
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4900

4901 4902 4903
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4904

4905
	selinux_netlbl_sk_security_reset(newsksec);
4906 4907
}

V
Venkat Yekkirala 已提交
4908
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4909
{
4910
	if (!sk)
V
Venkat Yekkirala 已提交
4911
		*secid = SECINITSID_ANY_SOCKET;
4912 4913
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4914

V
Venkat Yekkirala 已提交
4915
		*secid = sksec->sid;
4916
	}
4917 4918
}

4919
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4920
{
4921 4922
	struct inode_security_struct *isec =
		inode_security_novalidate(SOCK_INODE(parent));
4923 4924
	struct sk_security_struct *sksec = sk->sk_security;

4925 4926
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
4927
		isec->sid = sksec->sid;
4928
	sksec->sclass = isec->sclass;
4929 4930
}

4931 4932
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4933 4934 4935
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4936
	u16 family = req->rsk_ops->family;
4937
	u32 connsid;
4938 4939
	u32 peersid;

4940
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4941 4942
	if (err)
		return err;
4943 4944 4945 4946 4947
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4948

4949
	return selinux_netlbl_inet_conn_request(req, family);
4950 4951
}

4952 4953
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4954 4955 4956 4957
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4958
	newsksec->peer_sid = req->peer_secid;
4959 4960 4961 4962
	/* 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. */
4963

P
Paul Moore 已提交
4964 4965
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4966
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4967 4968
}

4969
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4970
{
4971
	u16 family = sk->sk_family;
4972 4973
	struct sk_security_struct *sksec = sk->sk_security;

4974 4975 4976 4977 4978
	/* 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);
4979 4980
}

4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001
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(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);
}

5002 5003
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
5004
{
5005
	fl->flowi_secid = req->secid;
5006 5007
}

5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025
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);
}

5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040
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(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
			    NULL);
}

5041
static int selinux_tun_dev_attach_queue(void *security)
5042
{
5043 5044 5045 5046 5047 5048 5049 5050 5051
	struct tun_security_struct *tunsec = security;

	return avc_has_perm(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;
5052 5053 5054 5055 5056 5057 5058 5059 5060
	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 */

5061
	sksec->sid = tunsec->sid;
5062
	sksec->sclass = SECCLASS_TUN_SOCKET;
5063 5064

	return 0;
5065 5066
}

5067
static int selinux_tun_dev_open(void *security)
5068
{
5069
	struct tun_security_struct *tunsec = security;
5070 5071 5072
	u32 sid = current_sid();
	int err;

5073
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5074 5075 5076 5077 5078 5079 5080
			   TUN_SOCKET__RELABELFROM, NULL);
	if (err)
		return err;
	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
			   TUN_SOCKET__RELABELTO, NULL);
	if (err)
		return err;
5081
	tunsec->sid = sid;
5082 5083 5084 5085

	return 0;
}

L
Linus Torvalds 已提交
5086 5087 5088 5089 5090
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
5091
	struct sk_security_struct *sksec = sk->sk_security;
5092

5093
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
5094 5095 5096
		err = -EINVAL;
		goto out;
	}
5097
	nlh = nlmsg_hdr(skb);
5098

5099
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
5100 5101
	if (err) {
		if (err == -EINVAL) {
5102 5103 5104
			pr_warn_ratelimited("SELinux: unrecognized netlink"
			       " message: protocol=%hu nlmsg_type=%hu sclass=%s"
			       " pig=%d comm=%s\n",
5105
			       sk->sk_protocol, nlh->nlmsg_type,
5106 5107
			       secclass_map[sksec->sclass - 1].name,
			       task_pid_nr(current), current->comm);
5108
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
5109 5110 5111 5112 5113 5114 5115 5116 5117
				err = 0;
		}

		/* Ignore */
		if (err == -ENOENT)
			err = 0;
		goto out;
	}

5118
	err = sock_has_perm(sk, perm);
L
Linus Torvalds 已提交
5119 5120 5121 5122 5123 5124
out:
	return err;
}

#ifdef CONFIG_NETFILTER

5125 5126
static unsigned int selinux_ip_forward(struct sk_buff *skb,
				       const struct net_device *indev,
5127
				       u16 family)
L
Linus Torvalds 已提交
5128
{
5129
	int err;
5130 5131
	char *addrp;
	u32 peer_sid;
5132
	struct common_audit_data ad;
5133
	struct lsm_network_audit net = {0,};
5134
	u8 secmark_active;
5135
	u8 netlbl_active;
5136
	u8 peerlbl_active;
5137

5138 5139
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
5140

5141
	secmark_active = selinux_secmark_enabled();
5142
	netlbl_active = netlbl_enabled();
5143
	peerlbl_active = selinux_peerlbl_enabled();
5144 5145
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
5146

5147 5148 5149
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

5150
	ad.type = LSM_AUDIT_DATA_NET;
5151
	ad.u.net = &net;
5152
	ad.u.net->netif = indev->ifindex;
5153
	ad.u.net->family = family;
5154 5155 5156
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

5157
	if (peerlbl_active) {
5158 5159
		err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
					       addrp, family, peer_sid, &ad);
5160
		if (err) {
5161
			selinux_netlbl_err(skb, family, err, 1);
5162
			return NF_DROP;
5163 5164
		}
	}
5165 5166 5167 5168 5169 5170

	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
			return NF_DROP;

5171 5172 5173 5174 5175 5176 5177 5178
	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;

5179 5180 5181
	return NF_ACCEPT;
}

5182
static unsigned int selinux_ipv4_forward(void *priv,
5183
					 struct sk_buff *skb,
5184
					 const struct nf_hook_state *state)
5185
{
5186
	return selinux_ip_forward(skb, state->in, PF_INET);
5187 5188
}

5189
#if IS_ENABLED(CONFIG_IPV6)
5190
static unsigned int selinux_ipv6_forward(void *priv,
5191
					 struct sk_buff *skb,
5192
					 const struct nf_hook_state *state)
5193
{
5194
	return selinux_ip_forward(skb, state->in, PF_INET6);
5195 5196 5197
}
#endif	/* IPV6 */

5198 5199 5200
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
5201
	struct sock *sk;
5202 5203 5204 5205 5206 5207 5208 5209
	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 */
5210 5211 5212 5213
	sk = skb->sk;
	if (sk) {
		struct sk_security_struct *sksec;

5214
		if (sk_listener(sk))
5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230
			/* 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;
5231 5232 5233 5234 5235 5236 5237 5238 5239
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

5240
static unsigned int selinux_ipv4_output(void *priv,
5241
					struct sk_buff *skb,
5242
					const struct nf_hook_state *state)
5243 5244 5245 5246
{
	return selinux_ip_output(skb, PF_INET);
}

5247
#if IS_ENABLED(CONFIG_IPV6)
5248 5249 5250 5251 5252 5253 5254 5255
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 */

5256 5257
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
5258
						u16 family)
5259
{
5260
	struct sock *sk = skb_to_full_sk(skb);
5261
	struct sk_security_struct *sksec;
5262
	struct common_audit_data ad;
5263
	struct lsm_network_audit net = {0,};
5264 5265
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
5266

5267 5268 5269 5270
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

5271
	ad.type = LSM_AUDIT_DATA_NET;
5272 5273 5274
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5275 5276 5277
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

5278
	if (selinux_secmark_enabled())
5279
		if (avc_has_perm(sksec->sid, skb->secmark,
5280
				 SECCLASS_PACKET, PACKET__SEND, &ad))
5281
			return NF_DROP_ERR(-ECONNREFUSED);
5282

5283 5284
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
5285 5286

	return NF_ACCEPT;
5287 5288
}

5289 5290
static unsigned int selinux_ip_postroute(struct sk_buff *skb,
					 const struct net_device *outdev,
5291
					 u16 family)
5292
{
5293 5294
	u32 secmark_perm;
	u32 peer_sid;
5295
	int ifindex = outdev->ifindex;
5296
	struct sock *sk;
5297
	struct common_audit_data ad;
5298
	struct lsm_network_audit net = {0,};
5299 5300 5301
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
5302

5303 5304 5305 5306
	/* 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. */
5307
	if (!selinux_policycap_netpeer)
5308
		return selinux_ip_postroute_compat(skb, ifindex, family);
5309 5310 5311 5312 5313 5314

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = selinux_peerlbl_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

5315
	sk = skb_to_full_sk(skb);
5316

5317
#ifdef CONFIG_XFRM
5318 5319 5320 5321 5322
	/* 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
5323 5324 5325 5326 5327 5328 5329
	 *       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 &&
5330
	    !(sk && sk_listener(sk)))
5331
		return NF_ACCEPT;
5332
#endif
5333

5334
	if (sk == NULL) {
5335 5336 5337 5338
		/* 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. */
5339 5340
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
5341
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5342
				return NF_DROP;
5343 5344
		} else {
			secmark_perm = PACKET__SEND;
5345
			peer_sid = SECINITSID_KERNEL;
5346
		}
5347
	} else if (sk_listener(sk)) {
5348 5349 5350 5351 5352 5353 5354 5355 5356 5357
		/* 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;
5358 5359 5360
		struct sk_security_struct *sksec;

		sksec = sk->sk_security;
5361 5362
		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
			return NF_DROP;
5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377
		/* 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;
5378
				break;
5379 5380 5381 5382
			default:
				return NF_DROP_ERR(-ECONNREFUSED);
			}
		}
5383 5384 5385
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
5386
	} else {
5387 5388
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
5389 5390 5391 5392
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
5393

5394
	ad.type = LSM_AUDIT_DATA_NET;
5395 5396 5397
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5398
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5399
		return NF_DROP;
5400

5401 5402 5403
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
5404
			return NF_DROP_ERR(-ECONNREFUSED);
5405 5406 5407 5408 5409

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

5410
		if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5411
			return NF_DROP;
5412 5413
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5414
			return NF_DROP_ERR(-ECONNREFUSED);
5415 5416

		if (sel_netnode_sid(addrp, family, &node_sid))
5417
			return NF_DROP;
5418 5419
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
5420
			return NF_DROP_ERR(-ECONNREFUSED);
5421
	}
5422

5423
	return NF_ACCEPT;
L
Linus Torvalds 已提交
5424 5425
}

5426
static unsigned int selinux_ipv4_postroute(void *priv,
5427
					   struct sk_buff *skb,
5428
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5429
{
5430
	return selinux_ip_postroute(skb, state->out, PF_INET);
L
Linus Torvalds 已提交
5431 5432
}

5433
#if IS_ENABLED(CONFIG_IPV6)
5434
static unsigned int selinux_ipv6_postroute(void *priv,
5435
					   struct sk_buff *skb,
5436
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5437
{
5438
	return selinux_ip_postroute(skb, state->out, PF_INET6);
L
Linus Torvalds 已提交
5439 5440 5441 5442 5443 5444 5445
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
{
5446
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
5447 5448
}

5449
static int ipc_alloc_security(struct kern_ipc_perm *perm,
L
Linus Torvalds 已提交
5450 5451 5452 5453
			      u16 sclass)
{
	struct ipc_security_struct *isec;

J
James Morris 已提交
5454
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5455 5456 5457 5458
	if (!isec)
		return -ENOMEM;

	isec->sclass = sclass;
5459
	isec->sid = current_sid();
L
Linus Torvalds 已提交
5460 5461 5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474 5475
	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;

J
James Morris 已提交
5476
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494
	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,
5495
			u32 perms)
L
Linus Torvalds 已提交
5496 5497
{
	struct ipc_security_struct *isec;
5498
	struct common_audit_data ad;
5499
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5500 5501 5502

	isec = ipc_perms->security;

5503
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5504 5505
	ad.u.ipc_id = ipc_perms->key;

5506
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5507 5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520 5521 5522
}

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 msg_queue *msq)
{
	struct ipc_security_struct *isec;
5523
	struct common_audit_data ad;
5524
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5525 5526
	int rc;

5527
	rc = ipc_alloc_security(&msq->q_perm, SECCLASS_MSGQ);
L
Linus Torvalds 已提交
5528 5529 5530 5531 5532
	if (rc)
		return rc;

	isec = msq->q_perm.security;

5533
	ad.type = LSM_AUDIT_DATA_IPC;
5534
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5535

5536
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552
			  MSGQ__CREATE, &ad);
	if (rc) {
		ipc_free_security(&msq->q_perm);
		return rc;
	}
	return 0;
}

static void selinux_msg_queue_free_security(struct msg_queue *msq)
{
	ipc_free_security(&msq->q_perm);
}

static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
	struct ipc_security_struct *isec;
5553
	struct common_audit_data ad;
5554
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5555 5556 5557

	isec = msq->q_perm.security;

5558
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5559 5560
	ad.u.ipc_id = msq->q_perm.key;

5561
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5562 5563 5564 5565 5566 5567 5568 5569
			    MSGQ__ASSOCIATE, &ad);
}

static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
{
	int err;
	int perms;

5570
	switch (cmd) {
L
Linus Torvalds 已提交
5571 5572 5573
	case IPC_INFO:
	case MSG_INFO:
		/* No specific object, just general system-wide information. */
5574 5575
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5576 5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589
	case IPC_STAT:
	case MSG_STAT:
		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
		break;
	case IPC_SET:
		perms = MSGQ__SETATTR;
		break;
	case IPC_RMID:
		perms = MSGQ__DESTROY;
		break;
	default:
		return 0;
	}

5590
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5591 5592 5593 5594 5595 5596 5597
	return err;
}

static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
5598
	struct common_audit_data ad;
5599
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612
	int rc;

	isec = msq->q_perm.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
		 */
5613
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5614
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5615 5616 5617 5618
		if (rc)
			return rc;
	}

5619
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5620 5621 5622
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5623
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5624 5625 5626
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5627 5628
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5629 5630
	if (!rc)
		/* Can the message be put in the queue? */
5631 5632
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5633 5634 5635 5636 5637 5638 5639 5640 5641 5642

	return rc;
}

static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
				    struct task_struct *target,
				    long type, int mode)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
5643
	struct common_audit_data ad;
5644
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5645 5646 5647 5648 5649
	int rc;

	isec = msq->q_perm.security;
	msec = msg->security;

5650
	ad.type = LSM_AUDIT_DATA_IPC;
5651
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5652

5653
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5654 5655
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5656
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5657 5658 5659 5660 5661 5662 5663 5664
				  SECCLASS_MSG, MSG__RECEIVE, &ad);
	return rc;
}

/* Shared Memory security operations */
static int selinux_shm_alloc_security(struct shmid_kernel *shp)
{
	struct ipc_security_struct *isec;
5665
	struct common_audit_data ad;
5666
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5667 5668
	int rc;

5669
	rc = ipc_alloc_security(&shp->shm_perm, SECCLASS_SHM);
L
Linus Torvalds 已提交
5670 5671 5672 5673 5674
	if (rc)
		return rc;

	isec = shp->shm_perm.security;

5675
	ad.type = LSM_AUDIT_DATA_IPC;
5676
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5677

5678
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694
			  SHM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&shp->shm_perm);
		return rc;
	}
	return 0;
}

static void selinux_shm_free_security(struct shmid_kernel *shp)
{
	ipc_free_security(&shp->shm_perm);
}

static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
{
	struct ipc_security_struct *isec;
5695
	struct common_audit_data ad;
5696
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5697 5698 5699

	isec = shp->shm_perm.security;

5700
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5701 5702
	ad.u.ipc_id = shp->shm_perm.key;

5703
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5704 5705 5706 5707 5708 5709 5710 5711 5712
			    SHM__ASSOCIATE, &ad);
}

/* Note, at this point, shp is locked down */
static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
{
	int perms;
	int err;

5713
	switch (cmd) {
L
Linus Torvalds 已提交
5714 5715 5716
	case IPC_INFO:
	case SHM_INFO:
		/* No specific object, just general system-wide information. */
5717 5718
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5719 5720 5721 5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734 5735 5736
	case IPC_STAT:
	case SHM_STAT:
		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;
	}

5737
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750
	return err;
}

static int selinux_shm_shmat(struct shmid_kernel *shp,
			     char __user *shmaddr, int shmflg)
{
	u32 perms;

	if (shmflg & SHM_RDONLY)
		perms = SHM__READ;
	else
		perms = SHM__READ | SHM__WRITE;

5751
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5752 5753 5754 5755 5756 5757
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5758
	struct common_audit_data ad;
5759
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5760 5761
	int rc;

5762
	rc = ipc_alloc_security(&sma->sem_perm, SECCLASS_SEM);
L
Linus Torvalds 已提交
5763 5764 5765 5766 5767
	if (rc)
		return rc;

	isec = sma->sem_perm.security;

5768
	ad.type = LSM_AUDIT_DATA_IPC;
5769
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5770

5771
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785 5786 5787
			  SEM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&sma->sem_perm);
		return rc;
	}
	return 0;
}

static void selinux_sem_free_security(struct sem_array *sma)
{
	ipc_free_security(&sma->sem_perm);
}

static int selinux_sem_associate(struct sem_array *sma, int semflg)
{
	struct ipc_security_struct *isec;
5788
	struct common_audit_data ad;
5789
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5790 5791 5792

	isec = sma->sem_perm.security;

5793
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5794 5795
	ad.u.ipc_id = sma->sem_perm.key;

5796
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5797 5798 5799 5800 5801 5802 5803 5804 5805
			    SEM__ASSOCIATE, &ad);
}

/* Note, at this point, sma is locked down */
static int selinux_sem_semctl(struct sem_array *sma, int cmd)
{
	int err;
	u32 perms;

5806
	switch (cmd) {
L
Linus Torvalds 已提交
5807 5808 5809
	case IPC_INFO:
	case SEM_INFO:
		/* No specific object, just general system-wide information. */
5810 5811
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5812 5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838
	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:
		perms = SEM__GETATTR | SEM__ASSOCIATE;
		break;
	default:
		return 0;
	}

5839
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5840 5841 5842 5843 5844 5845 5846 5847 5848 5849 5850 5851 5852
	return err;
}

static int selinux_sem_semop(struct sem_array *sma,
			     struct sembuf *sops, unsigned nsops, int alter)
{
	u32 perms;

	if (alter)
		perms = SEM__READ | SEM__WRITE;
	else
		perms = SEM__READ;

5853
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866 5867 5868
}

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;

5869
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5870 5871
}

5872 5873 5874 5875 5876 5877
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5878
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5879 5880 5881 5882 5883 5884
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5885
			       char *name, char **value)
L
Linus Torvalds 已提交
5886
{
5887
	const struct task_security_struct *__tsec;
5888
	u32 sid;
L
Linus Torvalds 已提交
5889
	int error;
5890
	unsigned len;
L
Linus Torvalds 已提交
5891

5892 5893 5894
	rcu_read_lock();
	__tsec = __task_cred(p)->security;

L
Linus Torvalds 已提交
5895
	if (current != p) {
5896 5897
		error = avc_has_perm(current_sid(), __tsec->sid,
				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
L
Linus Torvalds 已提交
5898
		if (error)
5899
			goto bad;
L
Linus Torvalds 已提交
5900 5901 5902
	}

	if (!strcmp(name, "current"))
5903
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5904
	else if (!strcmp(name, "prev"))
5905
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5906
	else if (!strcmp(name, "exec"))
5907
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5908
	else if (!strcmp(name, "fscreate"))
5909
		sid = __tsec->create_sid;
5910
	else if (!strcmp(name, "keycreate"))
5911
		sid = __tsec->keycreate_sid;
5912
	else if (!strcmp(name, "sockcreate"))
5913
		sid = __tsec->sockcreate_sid;
5914 5915 5916 5917
	else {
		error = -EINVAL;
		goto bad;
	}
5918
	rcu_read_unlock();
L
Linus Torvalds 已提交
5919 5920 5921 5922

	if (!sid)
		return 0;

5923 5924 5925 5926
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5927

5928
bad:
5929
	rcu_read_unlock();
5930
	return error;
L
Linus Torvalds 已提交
5931 5932
}

5933
static int selinux_setprocattr(const char *name, void *value, size_t size)
L
Linus Torvalds 已提交
5934 5935
{
	struct task_security_struct *tsec;
D
David Howells 已提交
5936
	struct cred *new;
5937
	u32 mysid = current_sid(), sid = 0, ptsid;
L
Linus Torvalds 已提交
5938 5939 5940 5941 5942 5943 5944
	int error;
	char *str = value;

	/*
	 * Basic control over ability to set these attributes at all.
	 */
	if (!strcmp(name, "exec"))
5945 5946
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETEXEC, NULL);
L
Linus Torvalds 已提交
5947
	else if (!strcmp(name, "fscreate"))
5948 5949
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETFSCREATE, NULL);
5950
	else if (!strcmp(name, "keycreate"))
5951 5952
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETKEYCREATE, NULL);
5953
	else if (!strcmp(name, "sockcreate"))
5954 5955
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETSOCKCREATE, NULL);
L
Linus Torvalds 已提交
5956
	else if (!strcmp(name, "current"))
5957 5958
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETCURRENT, NULL);
L
Linus Torvalds 已提交
5959 5960 5961 5962 5963 5964
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
5965
	if (size && str[0] && str[0] != '\n') {
L
Linus Torvalds 已提交
5966 5967 5968 5969
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
5970
		error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5971
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5972
			if (!has_cap_mac_admin(true)) {
5973 5974 5975 5976 5977 5978 5979 5980 5981 5982 5983 5984 5985 5986
				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(current->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);

5987
				return error;
5988
			}
5989 5990 5991
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5992 5993 5994 5995
		if (error)
			return error;
	}

D
David Howells 已提交
5996 5997 5998 5999
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
6000 6001 6002
	/* Permission checking based on the specified context is
	   performed during the actual operation (execve,
	   open/mkdir/...), when we know the full context of the
D
David Howells 已提交
6003
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
6004 6005
	   checks and may_create for the file creation checks. The
	   operation will then fail if the context is not permitted. */
D
David Howells 已提交
6006 6007
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
6008
		tsec->exec_sid = sid;
D
David Howells 已提交
6009
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
6010
		tsec->create_sid = sid;
D
David Howells 已提交
6011
	} else if (!strcmp(name, "keycreate")) {
6012 6013
		error = avc_has_perm(mysid, sid, SECCLASS_KEY, KEY__CREATE,
				     NULL);
6014
		if (error)
D
David Howells 已提交
6015
			goto abort_change;
6016
		tsec->keycreate_sid = sid;
D
David Howells 已提交
6017
	} else if (!strcmp(name, "sockcreate")) {
6018
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
6019 6020
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
6021
		if (sid == 0)
D
David Howells 已提交
6022 6023 6024 6025
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
6026
		if (!current_is_single_threaded()) {
D
David Howells 已提交
6027 6028 6029
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
6030
		}
L
Linus Torvalds 已提交
6031 6032 6033

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6034
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
6035
		if (error)
D
David Howells 已提交
6036
			goto abort_change;
L
Linus Torvalds 已提交
6037 6038 6039

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
6040
		ptsid = ptrace_parent_sid();
6041
		if (ptsid != 0) {
D
David Howells 已提交
6042 6043
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
6044
			if (error)
D
David Howells 已提交
6045
				goto abort_change;
L
Linus Torvalds 已提交
6046 6047
		}

D
David Howells 已提交
6048 6049 6050 6051 6052 6053 6054
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
6055
	return size;
D
David Howells 已提交
6056 6057 6058 6059

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
6060 6061
}

6062 6063 6064 6065 6066
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

6067 6068 6069 6070 6071
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

6072
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6073
{
6074
	return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
6075 6076
}

6077 6078
static void selinux_release_secctx(char *secdata, u32 seclen)
{
6079
	kfree(secdata);
6080 6081
}

6082 6083 6084 6085
static void selinux_inode_invalidate_secctx(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;

6086
	spin_lock(&isec->lock);
6087
	isec->initialized = LABEL_INVALID;
6088
	spin_unlock(&isec->lock);
6089 6090
}

6091 6092 6093 6094 6095 6096 6097 6098 6099 6100 6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113 6114 6115 6116
/*
 *	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;
}
6117 6118
#ifdef CONFIG_KEYS

D
David Howells 已提交
6119
static int selinux_key_alloc(struct key *k, const struct cred *cred,
6120
			     unsigned long flags)
6121
{
D
David Howells 已提交
6122
	const struct task_security_struct *tsec;
6123 6124 6125 6126 6127 6128
	struct key_security_struct *ksec;

	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
	if (!ksec)
		return -ENOMEM;

D
David Howells 已提交
6129 6130 6131
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
6132
	else
D
David Howells 已提交
6133
		ksec->sid = tsec->sid;
6134

6135
	k->security = ksec;
6136 6137 6138 6139 6140 6141 6142 6143 6144 6145 6146 6147
	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,
D
David Howells 已提交
6148
				  const struct cred *cred,
6149
				  unsigned perm)
6150 6151 6152
{
	struct key *key;
	struct key_security_struct *ksec;
6153
	u32 sid;
6154 6155 6156 6157 6158 6159 6160

	/* 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;

D
David Howells 已提交
6161
	sid = cred_sid(cred);
6162 6163 6164 6165 6166

	key = key_ref_to_ptr(key_ref);
	ksec = key->security;

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6167 6168
}

6169 6170 6171 6172 6173 6174 6175 6176 6177 6178 6179 6180 6181
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(ksec->sid, &context, &len);
	if (!rc)
		rc = len;
	*_buffer = context;
	return rc;
}
6182 6183 6184
#endif

#ifdef CONFIG_SECURITY_INFINIBAND
6185 6186 6187 6188 6189 6190 6191 6192
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;

6193
	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6194 6195 6196 6197 6198 6199 6200 6201 6202 6203 6204 6205
	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(sec->sid, sid,
			    SECCLASS_INFINIBAND_PKEY,
			    INFINIBAND_PKEY__ACCESS, &ad);
}

6206 6207 6208 6209 6210 6211 6212 6213 6214 6215 6216 6217 6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228
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(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(sec->sid, sid,
			    SECCLASS_INFINIBAND_ENDPORT,
			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
}

6229 6230 6231 6232 6233 6234 6235 6236 6237 6238 6239 6240
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;
}
6241

6242 6243 6244 6245
static void selinux_ib_free_security(void *ib_sec)
{
	kfree(ib_sec);
}
6246 6247
#endif

6248
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6249 6250 6251 6252 6253 6254 6255 6256 6257 6258 6259 6260 6261 6262 6263 6264 6265 6266 6267 6268 6269 6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284
	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(bprm_secureexec, selinux_bprm_secureexec),

	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),
6285
	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6286 6287 6288 6289 6290 6291 6292 6293 6294 6295 6296 6297 6298 6299 6300 6301 6302 6303 6304 6305 6306 6307 6308 6309 6310 6311

	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),
6312
	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6313
	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326 6327 6328 6329

	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),

6330
	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6331 6332 6333 6334 6335 6336 6337
	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(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),
6338
	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6339 6340 6341 6342 6343 6344 6345
	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),
6346
	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6347 6348 6349 6350 6351 6352 6353 6354 6355 6356 6357 6358 6359 6360 6361 6362 6363 6364 6365 6366 6367 6368 6369 6370 6371 6372 6373 6374 6375 6376 6377 6378 6379 6380 6381 6382 6383 6384 6385 6386 6387 6388
	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),
6389
	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6390 6391 6392 6393 6394 6395 6396 6397 6398 6399 6400 6401 6402 6403 6404 6405 6406 6407 6408 6409 6410 6411 6412 6413 6414 6415 6416 6417 6418 6419 6420 6421 6422 6423 6424 6425 6426 6427 6428 6429 6430 6431
	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_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(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),
6432
#ifdef CONFIG_SECURITY_INFINIBAND
6433
	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
6434 6435
	LSM_HOOK_INIT(ib_endport_manage_subnet,
		      selinux_ib_endport_manage_subnet),
6436 6437 6438
	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
#endif
6439
#ifdef CONFIG_SECURITY_NETWORK_XFRM
6440 6441 6442 6443 6444 6445 6446 6447 6448 6449 6450 6451 6452
	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),
L
Linus Torvalds 已提交
6453
#endif
6454 6455

#ifdef CONFIG_KEYS
6456 6457 6458 6459
	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),
6460
#endif
6461 6462

#ifdef CONFIG_AUDIT
6463 6464 6465 6466
	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),
6467
#endif
L
Linus Torvalds 已提交
6468 6469 6470 6471
};

static __init int selinux_init(void)
{
C
Casey Schaufler 已提交
6472
	if (!security_module_enable("selinux")) {
6473 6474 6475 6476
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
6477 6478 6479 6480 6481 6482 6483 6484
	if (!selinux_enabled) {
		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
		return 0;
	}

	printk(KERN_INFO "SELinux:  Initializing.\n");

	/* Set the security state for the initial task. */
D
David Howells 已提交
6485
	cred_init_security();
L
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6486

6487 6488
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

6489 6490
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
6491
					    0, SLAB_PANIC, NULL);
6492 6493 6494
	file_security_cache = kmem_cache_create("selinux_file_security",
					    sizeof(struct file_security_struct),
					    0, SLAB_PANIC, NULL);
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	avc_init();

6497
	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
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6498

6499 6500 6501
	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC netcache callback\n");

6502 6503 6504
	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC LSM notifier callback\n");

6505
	if (selinux_enforcing)
6506
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
6507
	else
6508
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6509

L
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	return 0;
}

6513 6514 6515 6516 6517
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

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void selinux_complete_init(void)
{
6520
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
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6521 6522

	/* Set up any superblocks initialized prior to the policy load. */
6523
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6524
	iterate_supers(delayed_superblock_init, NULL);
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}

/* SELinux requires early initialization in order to label
   all processes and objects when they are created. */
security_initcall(selinux_init);

6531
#if defined(CONFIG_NETFILTER)
L
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6533
static struct nf_hook_ops selinux_nf_ops[] = {
6534 6535
	{
		.hook =		selinux_ipv4_postroute,
6536
		.pf =		NFPROTO_IPV4,
6537 6538 6539 6540 6541
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
6542
		.pf =		NFPROTO_IPV4,
6543 6544
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6545 6546 6547
	},
	{
		.hook =		selinux_ipv4_output,
6548
		.pf =		NFPROTO_IPV4,
6549 6550
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6551
	},
6552
#if IS_ENABLED(CONFIG_IPV6)
6553 6554
	{
		.hook =		selinux_ipv6_postroute,
6555
		.pf =		NFPROTO_IPV6,
6556 6557 6558 6559 6560
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
6561
		.pf =		NFPROTO_IPV6,
6562 6563
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
6564
	},
6565 6566 6567 6568 6569 6570
	{
		.hook =		selinux_ipv6_output,
		.pf =		NFPROTO_IPV6,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	},
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Linus Torvalds 已提交
6571
#endif	/* IPV6 */
6572
};
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6573

6574 6575 6576 6577 6578 6579 6580 6581 6582 6583 6584 6585 6586 6587 6588 6589 6590
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,
};

L
Linus Torvalds 已提交
6591 6592
static int __init selinux_nf_ip_init(void)
{
6593
	int err;
L
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6594 6595

	if (!selinux_enabled)
6596
		return 0;
6597 6598 6599

	printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");

6600
	err = register_pernet_subsys(&selinux_net_ops);
6601
	if (err)
6602
		panic("SELinux: register_pernet_subsys: error %d\n", err);
L
Linus Torvalds 已提交
6603

6604
	return 0;
L
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6605 6606 6607 6608 6609 6610
}
__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6611
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
6612

6613
	unregister_pernet_subsys(&selinux_net_ops);
L
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6614 6615 6616
}
#endif

6617
#else /* CONFIG_NETFILTER */
L
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6618 6619 6620 6621 6622

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6623
#endif /* CONFIG_NETFILTER */
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6624 6625

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6626 6627
static int selinux_disabled;

L
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6628 6629 6630 6631 6632 6633 6634 6635 6636 6637 6638 6639 6640 6641 6642
int selinux_disable(void)
{
	if (ss_initialized) {
		/* Not permitted after initial policy load. */
		return -EINVAL;
	}

	if (selinux_disabled) {
		/* Only do this once. */
		return -EINVAL;
	}

	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");

	selinux_disabled = 1;
6643
	selinux_enabled = 0;
L
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6644

C
Casey Schaufler 已提交
6645
	security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
L
Linus Torvalds 已提交
6646

6647 6648 6649
	/* Try to destroy the avc node cache */
	avc_disable();

L
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6650 6651 6652 6653 6654 6655 6656 6657 6658
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif