hooks.c 165.0 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 "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)
{
	if (event == AVC_CALLBACK_RESET)
		call_lsm_notifier(LSM_POLICY_CHANGE, NULL);

	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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	if (selinux_is_sblabel_mnt(sb))
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		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,
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				struct security_mnt_opts *opts)
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{
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	char *context = NULL;
	u32 len;
	char tmp;
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	security_init_mnt_opts(opts);
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573

574
	if (!(sbsec->flags & SE_SBINITIALIZED))
575
		return -EINVAL;
L
Linus Torvalds 已提交
576

577 578
	if (!ss_initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
579

580 581 582
	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

583
	tmp = sbsec->flags & SE_MNTMASK;
584
	/* count the number of mount options for this sb */
585
	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
586
		if (tmp & 0x01)
587
			opts->num_mnt_opts++;
588 589
		tmp >>= 1;
	}
590
	/* Check if the Label support flag is set */
591
	if (sbsec->flags & SBLABEL_MNT)
592
		opts->num_mnt_opts++;
L
Linus Torvalds 已提交
593

594 595
	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
596 597 598
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
599

600 601
	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
602 603 604
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
605

606 607 608 609 610
	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
611 612
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
613 614 615 616 617
	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
618 619
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
620 621 622 623 624
	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
625 626
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
627 628
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
629 630
		struct dentry *root = sbsec->sb->s_root;
		struct inode_security_struct *isec = backing_inode_security(root);
631

632 633 634
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
635 636
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
637
	}
638
	if (sbsec->flags & SBLABEL_MNT) {
639
		opts->mnt_opts[i] = NULL;
640
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
641
	}
L
Linus Torvalds 已提交
642

643
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
644

645 646 647
	return 0;

out_free:
648
	security_free_mnt_opts(opts);
649 650
	return rc;
}
L
Linus Torvalds 已提交
651

652 653 654
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
655 656
	char mnt_flags = sbsec->flags & SE_MNTMASK;

657
	/* check if the old mount command had the same options */
658
	if (sbsec->flags & SE_SBINITIALIZED)
659 660 661 662 663 664 665
		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
	 */
666 667
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
668 669 670
			return 1;
	return 0;
}
671

672 673 674 675
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
676
static int selinux_set_mnt_opts(struct super_block *sb,
677 678 679
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
680
{
681
	const struct cred *cred = current_cred();
682 683
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
684
	const char *name = sb->s_type->name;
685
	struct dentry *root = sbsec->sb->s_root;
686
	struct inode_security_struct *root_isec;
687 688
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
689 690 691
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
692 693 694 695 696 697 698 699 700 701 702

	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
703 704
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
705
		goto out;
706
	}
707 708 709 710 711 712
	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
713

714 715 716 717 718 719 720 721 722 723 724
	/*
	 * 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)
	 */
725
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
726
	    && (num_opts == 0))
727
		goto out;
728

729 730
	root_isec = backing_inode_security_novalidate(root);

731 732 733 734 735 736 737
	/*
	 * 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;
738

739
		if (flags[i] == SBLABEL_MNT)
740
			continue;
741
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
L
Linus Torvalds 已提交
742
		if (rc) {
743
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
744 745
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789
			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
790
		}
791 792
	}

793
	if (sbsec->flags & SE_SBINITIALIZED) {
794
		/* previously mounted with options, but not on this attempt? */
795
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
796 797 798 799 800
			goto out_double_mount;
		rc = 0;
		goto out;
	}

801
	if (strcmp(sb->s_type->name, "proc") == 0)
802 803
		sbsec->flags |= SE_SBPROC | SE_SBGENFS;

804 805 806
	if (!strcmp(sb->s_type->name, "debugfs") ||
	    !strcmp(sb->s_type->name, "sysfs") ||
	    !strcmp(sb->s_type->name, "pstore"))
807
		sbsec->flags |= SE_SBGENFS;
808

809 810 811 812 813
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
814
		rc = security_fs_use(sb);
815 816 817 818 819 820
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
821
	}
822 823

	/*
824 825 826
	 * 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.
827
	 */
828 829 830 831
	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")) {
832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847
		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;
	}

848 849
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
850
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
851
		if (rc)
852
			goto out;
L
Linus Torvalds 已提交
853

854
		sbsec->sid = fscontext_sid;
855 856 857 858 859 860 861
	}

	/*
	 * 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.
	 */
862 863 864 865 866
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

867 868
	if (context_sid) {
		if (!fscontext_sid) {
869 870
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
871
			if (rc)
872 873
				goto out;
			sbsec->sid = context_sid;
874
		} else {
875 876
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
877
			if (rc)
878
				goto out;
879
		}
880 881
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
882

883
		sbsec->mntpoint_sid = context_sid;
884
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
885 886
	}

887
	if (rootcontext_sid) {
888 889
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
890
		if (rc)
891
			goto out;
892

893
		root_isec->sid = rootcontext_sid;
894
		root_isec->initialized = LABEL_INITIALIZED;
895 896
	}

897
	if (defcontext_sid) {
898 899
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
900 901 902 903
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
904 905
		}

906 907
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
908
							     sbsec, cred);
909 910 911
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
912

913
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
914 915
	}

916
out_set_opts:
917
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
918
out:
919
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
920
	return rc;
921 922 923
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
924
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
925
	goto out;
L
Linus Torvalds 已提交
926 927
}

928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944
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) {
945 946
		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
947 948 949 950 951 952 953 954 955 956 957 958
		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,
959
					struct super_block *newsb)
L
Linus Torvalds 已提交
960
{
961 962
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
963

964 965 966
	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
967

968 969
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
970
	 * mount options.  thus we can safely deal with this superblock later
971
	 */
972
	if (!ss_initialized)
973
		return 0;
974 975

	/* how can we clone if the old one wasn't set up?? */
976
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
977

978
	/* if fs is reusing a sb, make sure that the contexts match */
979
	if (newsbsec->flags & SE_SBINITIALIZED)
980
		return selinux_cmp_sb_context(oldsb, newsb);
981

982 983 984 985 986 987 988 989 990 991 992 993 994 995
	mutex_lock(&newsbsec->lock);

	newsbsec->flags = oldsbsec->flags;

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

	if (set_context) {
		u32 sid = oldsbsec->mntpoint_sid;

		if (!set_fscontext)
			newsbsec->sid = sid;
		if (!set_rootcontext) {
996
			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
997 998 999
			newisec->sid = sid;
		}
		newsbsec->mntpoint_sid = sid;
L
Linus Torvalds 已提交
1000
	}
1001
	if (set_rootcontext) {
1002 1003
		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
1004

1005
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
1006 1007
	}

1008 1009
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
1010
	return 0;
1011 1012
}

1013 1014
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
1015
{
1016
	char *p;
1017 1018
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
1019
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
1020

1021
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
1022

1023 1024 1025 1026
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
1027

1028 1029
		if (!*p)
			continue;
L
Linus Torvalds 已提交
1030

1031
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
1032

1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084
		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;
1085 1086
		case Opt_labelsupport:
			break;
1087 1088 1089 1090
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
1091 1092 1093

		}
	}
1094

1095
	rc = -ENOMEM;
1096
	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1097 1098 1099
	if (!opts->mnt_opts)
		goto out_err;

1100 1101
	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
				       GFP_KERNEL);
1102 1103 1104 1105 1106
	if (!opts->mnt_opts_flags) {
		kfree(opts->mnt_opts);
		goto out_err;
	}

1107
	if (fscontext) {
1108 1109
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1110 1111
	}
	if (context) {
1112 1113
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1114 1115
	}
	if (rootcontext) {
1116 1117
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1118 1119
	}
	if (defcontext) {
1120 1121
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1122 1123
	}

1124 1125 1126
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1127 1128 1129 1130 1131
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1132 1133
	return rc;
}
1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154
/*
 * 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:
1155
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1156 1157 1158 1159 1160

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1161

A
Adrian Bunk 已提交
1162 1163
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1164 1165 1166 1167 1168
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1169 1170 1171 1172 1173 1174
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188

		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;
1189
		case SBLABEL_MNT:
1190 1191 1192
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1193 1194
		default:
			BUG();
1195
			return;
1196 1197 1198 1199 1200 1201
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
1202
		seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213
		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);
1214 1215 1216 1217
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1218
		return rc;
1219
	}
1220 1221 1222 1223 1224 1225 1226 1227

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250
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;
}

1251 1252 1253 1254 1255 1256 1257 1258 1259 1260
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
1261 1262
static inline u16 socket_type_to_security_class(int family, int type, int protocol)
{
1263 1264
	int extsockclass = selinux_policycap_extsockclass;

L
Linus Torvalds 已提交
1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278
	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:
1279
		case SOCK_SEQPACKET:
1280 1281
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
1282 1283
			else if (extsockclass && protocol == IPPROTO_SCTP)
				return SECCLASS_SCTP_SOCKET;
1284 1285
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1286
		case SOCK_DGRAM:
1287 1288
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
1289 1290
			else if (extsockclass && (protocol == IPPROTO_ICMP ||
						  protocol == IPPROTO_ICMPV6))
1291
				return SECCLASS_ICMP_SOCKET;
1292 1293
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1294 1295
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1296
		default:
L
Linus Torvalds 已提交
1297 1298 1299 1300 1301 1302 1303
			return SECCLASS_RAWIP_SOCKET;
		}
		break;
	case PF_NETLINK:
		switch (protocol) {
		case NETLINK_ROUTE:
			return SECCLASS_NETLINK_ROUTE_SOCKET;
1304
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1305 1306 1307 1308 1309 1310 1311
			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;
1312 1313
		case NETLINK_ISCSI:
			return SECCLASS_NETLINK_ISCSI_SOCKET;
L
Linus Torvalds 已提交
1314 1315
		case NETLINK_AUDIT:
			return SECCLASS_NETLINK_AUDIT_SOCKET;
1316 1317 1318 1319 1320 1321
		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
1322 1323
		case NETLINK_DNRTMSG:
			return SECCLASS_NETLINK_DNRT_SOCKET;
1324 1325
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1326 1327 1328 1329 1330 1331 1332 1333
		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
1334 1335 1336 1337 1338 1339 1340
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1341 1342
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1343 1344
	}

1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398
	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;
1399 1400 1401
		case PF_SMC:
			return SECCLASS_SMC_SOCKET;
#if PF_MAX > 44
1402 1403 1404 1405 1406
#error New address family defined, please update this function.
#endif
		}
	}

L
Linus Torvalds 已提交
1407 1408 1409
	return SECCLASS_SOCKET;
}

1410 1411 1412 1413
static int selinux_genfs_get_sid(struct dentry *dentry,
				 u16 tclass,
				 u16 flags,
				 u32 *sid)
L
Linus Torvalds 已提交
1414
{
1415
	int rc;
1416
	struct super_block *sb = dentry->d_sb;
1417
	char *buffer, *path;
L
Linus Torvalds 已提交
1418

1419
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1420 1421 1422
	if (!buffer)
		return -ENOMEM;

1423 1424 1425 1426
	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
	if (IS_ERR(path))
		rc = PTR_ERR(path);
	else {
1427 1428 1429 1430 1431 1432 1433 1434
		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++;
			}
1435
		}
1436
		rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
L
Linus Torvalds 已提交
1437 1438 1439 1440 1441 1442 1443 1444 1445 1446
	}
	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;
1447 1448
	u32 task_sid, sid = 0;
	u16 sclass;
L
Linus Torvalds 已提交
1449 1450 1451 1452 1453 1454
	struct dentry *dentry;
#define INITCONTEXTLEN 255
	char *context = NULL;
	unsigned len = 0;
	int rc = 0;

1455
	if (isec->initialized == LABEL_INITIALIZED)
1456
		return 0;
L
Linus Torvalds 已提交
1457

1458
	spin_lock(&isec->lock);
1459
	if (isec->initialized == LABEL_INITIALIZED)
1460
		goto out_unlock;
L
Linus Torvalds 已提交
1461

1462 1463 1464
	if (isec->sclass == SECCLASS_FILE)
		isec->sclass = inode_mode_to_security_class(inode->i_mode);

L
Linus Torvalds 已提交
1465
	sbsec = inode->i_sb->s_security;
1466
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1467 1468 1469 1470 1471 1472 1473
		/* 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);
1474
		goto out_unlock;
L
Linus Torvalds 已提交
1475 1476
	}

1477 1478 1479 1480 1481 1482
	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
1483
	switch (sbsec->behavior) {
1484 1485
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1486
	case SECURITY_FS_USE_XATTR:
1487
		if (!(inode->i_opflags & IOP_XATTR)) {
1488
			sid = sbsec->def_sid;
L
Linus Torvalds 已提交
1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500
			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) {
1501 1502 1503 1504 1505 1506 1507 1508 1509
			/*
			 * 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.
			 */
1510
			goto out;
L
Linus Torvalds 已提交
1511 1512 1513
		}

		len = INITCONTEXTLEN;
1514
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1515 1516 1517
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1518
			goto out;
L
Linus Torvalds 已提交
1519
		}
1520
		context[len] = '\0';
1521
		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
L
Linus Torvalds 已提交
1522
		if (rc == -ERANGE) {
1523 1524
			kfree(context);

L
Linus Torvalds 已提交
1525
			/* Need a larger buffer.  Query for the right size. */
1526
			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
L
Linus Torvalds 已提交
1527 1528
			if (rc < 0) {
				dput(dentry);
1529
				goto out;
L
Linus Torvalds 已提交
1530 1531
			}
			len = rc;
1532
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1533 1534 1535
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1536
				goto out;
L
Linus Torvalds 已提交
1537
			}
1538
			context[len] = '\0';
1539
			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
L
Linus Torvalds 已提交
1540 1541 1542 1543
		}
		dput(dentry);
		if (rc < 0) {
			if (rc != -ENODATA) {
E
Eric Paris 已提交
1544
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1545
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1546 1547
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1548
				goto out;
L
Linus Torvalds 已提交
1549 1550 1551 1552 1553
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1554
			rc = security_context_to_sid_default(context, rc, &sid,
1555 1556
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1557
			if (rc) {
1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570
				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
1571 1572 1573 1574 1575 1576 1577 1578 1579
				kfree(context);
				/* Leave with the unlabeled SID */
				rc = 0;
				break;
			}
		}
		kfree(context);
		break;
	case SECURITY_FS_USE_TASK:
1580
		sid = task_sid;
L
Linus Torvalds 已提交
1581 1582 1583
		break;
	case SECURITY_FS_USE_TRANS:
		/* Default to the fs SID. */
1584
		sid = sbsec->sid;
L
Linus Torvalds 已提交
1585 1586

		/* Try to obtain a transition SID. */
1587
		rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid);
L
Linus Torvalds 已提交
1588
		if (rc)
1589
			goto out;
L
Linus Torvalds 已提交
1590
		break;
1591
	case SECURITY_FS_USE_MNTPOINT:
1592
		sid = sbsec->mntpoint_sid;
1593
		break;
L
Linus Torvalds 已提交
1594
	default:
1595
		/* Default to the fs superblock SID. */
1596
		sid = sbsec->sid;
L
Linus Torvalds 已提交
1597

1598
		if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618
			/* 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)
1619 1620
				goto out;
			rc = selinux_genfs_get_sid(dentry, sclass,
1621
						   sbsec->flags, &sid);
1622 1623
			dput(dentry);
			if (rc)
1624
				goto out;
L
Linus Torvalds 已提交
1625 1626 1627 1628
		}
		break;
	}

1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639
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
1640

1641
out_unlock:
1642
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672
	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;
}

1673 1674 1675 1676
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1677
/* Check whether a task is allowed to use a capability. */
1678
static int cred_has_capability(const struct cred *cred,
1679
			       int cap, int audit, bool initns)
L
Linus Torvalds 已提交
1680
{
1681
	struct common_audit_data ad;
1682
	struct av_decision avd;
1683
	u16 sclass;
1684
	u32 sid = cred_sid(cred);
1685
	u32 av = CAP_TO_MASK(cap);
1686
	int rc;
L
Linus Torvalds 已提交
1687

1688
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1689 1690
	ad.u.cap = cap;

1691 1692
	switch (CAP_TO_INDEX(cap)) {
	case 0:
1693
		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1694 1695
		break;
	case 1:
1696
		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1697 1698 1699 1700 1701
		break;
	default:
		printk(KERN_ERR
		       "SELinux:  out of range capability %d\n", cap);
		BUG();
1702
		return -EINVAL;
1703
	}
1704

1705
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1706
	if (audit == SECURITY_CAP_AUDIT) {
1707
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1708 1709 1710
		if (rc2)
			return rc2;
	}
1711
	return rc;
L
Linus Torvalds 已提交
1712 1713 1714 1715 1716
}

/* 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). */
1717
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1718 1719
			  struct inode *inode,
			  u32 perms,
1720
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1721 1722
{
	struct inode_security_struct *isec;
1723
	u32 sid;
L
Linus Torvalds 已提交
1724

1725 1726
	validate_creds(cred);

1727
	if (unlikely(IS_PRIVATE(inode)))
1728 1729
		return 0;

1730
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1731 1732
	isec = inode->i_security;

1733
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1734 1735 1736 1737 1738
}

/* 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. */
1739
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1740 1741 1742
				  struct dentry *dentry,
				  u32 av)
{
1743
	struct inode *inode = d_backing_inode(dentry);
1744
	struct common_audit_data ad;
1745

1746
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1747
	ad.u.dentry = dentry;
1748
	__inode_security_revalidate(inode, dentry, true);
1749
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1750 1751 1752 1753 1754 1755
}

/* 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,
1756
				const struct path *path,
E
Eric Paris 已提交
1757 1758
				u32 av)
{
1759
	struct inode *inode = d_backing_inode(path->dentry);
E
Eric Paris 已提交
1760 1761
	struct common_audit_data ad;

1762
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1763
	ad.u.path = *path;
1764
	__inode_security_revalidate(inode, path->dentry, true);
1765
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1766 1767
}

1768 1769 1770 1771 1772 1773 1774
/* 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;

1775 1776
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
1777
	return inode_has_perm(cred, file_inode(file), av, &ad);
1778 1779
}

L
Linus Torvalds 已提交
1780 1781 1782 1783 1784 1785 1786 1787
/* 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. */
1788 1789 1790
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1791 1792
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1793
	struct inode *inode = file_inode(file);
1794
	struct common_audit_data ad;
1795
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1796 1797
	int rc;

1798 1799
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
L
Linus Torvalds 已提交
1800

1801 1802
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1803 1804 1805 1806
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1807
			goto out;
L
Linus Torvalds 已提交
1808 1809 1810
	}

	/* av is zero if only checking access to the descriptor. */
1811
	rc = 0;
L
Linus Torvalds 已提交
1812
	if (av)
1813
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1814

1815 1816
out:
	return rc;
L
Linus Torvalds 已提交
1817 1818
}

1819 1820 1821
/*
 * Determine the label for an inode that might be unioned.
 */
1822 1823 1824 1825 1826
static int
selinux_determine_inode_label(const struct task_security_struct *tsec,
				 struct inode *dir,
				 const struct qstr *name, u16 tclass,
				 u32 *_new_isid)
1827 1828 1829 1830 1831 1832 1833 1834 1835 1836
{
	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 {
1837
		const struct inode_security_struct *dsec = inode_security(dir);
1838 1839 1840 1841 1842 1843 1844
		return security_transition_sid(tsec->sid, dsec->sid, tclass,
					       name, _new_isid);
	}

	return 0;
}

L
Linus Torvalds 已提交
1845 1846 1847 1848 1849
/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1850
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1851 1852
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1853
	u32 sid, newsid;
1854
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1855 1856
	int rc;

1857
	dsec = inode_security(dir);
L
Linus Torvalds 已提交
1858 1859
	sbsec = dir->i_sb->s_security;

1860 1861
	sid = tsec->sid;

1862
	ad.type = LSM_AUDIT_DATA_DENTRY;
1863
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1864

1865
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1866 1867 1868 1869 1870
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1871 1872
	rc = selinux_determine_inode_label(current_security(), dir,
					   &dentry->d_name, tclass, &newsid);
1873 1874
	if (rc)
		return rc;
L
Linus Torvalds 已提交
1875

1876
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1877 1878 1879 1880 1881 1882 1883 1884
	if (rc)
		return rc;

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

1885 1886 1887
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1888 1889 1890 1891 1892 1893 1894 1895

/* 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;
1896
	struct common_audit_data ad;
1897
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1898 1899 1900
	u32 av;
	int rc;

1901 1902
	dsec = inode_security(dir);
	isec = backing_inode_security(dentry);
L
Linus Torvalds 已提交
1903

1904
	ad.type = LSM_AUDIT_DATA_DENTRY;
1905
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1906 1907 1908

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1909
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923
	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
1924 1925
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1926 1927 1928
		return 0;
	}

1929
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1930 1931 1932 1933 1934 1935 1936 1937 1938
	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;
1939
	struct common_audit_data ad;
1940
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1941 1942 1943 1944
	u32 av;
	int old_is_dir, new_is_dir;
	int rc;

1945 1946
	old_dsec = inode_security(old_dir);
	old_isec = backing_inode_security(old_dentry);
1947
	old_is_dir = d_is_dir(old_dentry);
1948
	new_dsec = inode_security(new_dir);
L
Linus Torvalds 已提交
1949

1950
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1951

1952
	ad.u.dentry = old_dentry;
1953
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1954 1955 1956
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1957
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1958 1959 1960 1961
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1962
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1963 1964 1965 1966 1967
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1968
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1969
	av = DIR__ADD_NAME | DIR__SEARCH;
1970
	if (d_is_positive(new_dentry))
L
Linus Torvalds 已提交
1971
		av |= DIR__REMOVE_NAME;
1972
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1973 1974
	if (rc)
		return rc;
1975
	if (d_is_positive(new_dentry)) {
1976
		new_isec = backing_inode_security(new_dentry);
1977
		new_is_dir = d_is_dir(new_dentry);
1978
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1979 1980 1981 1982 1983 1984 1985 1986 1987 1988
				  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. */
1989
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1990 1991
			       struct super_block *sb,
			       u32 perms,
1992
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1993 1994
{
	struct superblock_security_struct *sbsec;
1995
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1996 1997

	sbsec = sb->s_security;
1998
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1999 2000 2001 2002 2003 2004 2005
}

/* 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
2006
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028
		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;
}

2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051
/* 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
2052
/*
2053
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
2054 2055
 * open permission.
 */
2056
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
2057
{
2058
	u32 av = file_to_av(file);
2059
	struct inode *inode = file_inode(file);
E
Eric Paris 已提交
2060

2061
	if (selinux_policycap_openperm && inode->i_sb->s_magic != SOCKFS_MAGIC)
2062 2063
		av |= FILE__OPEN;

E
Eric Paris 已提交
2064 2065 2066
	return av;
}

L
Linus Torvalds 已提交
2067 2068
/* Hook functions begin here. */

2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112
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;
2113
	struct dentry *dentry = file->f_path.dentry;
2114
	struct inode_security_struct *isec;
2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129
	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;
	}

2130
	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2131 2132
		return 0;

2133
	isec = backing_inode_security(dentry);
2134 2135 2136 2137
	return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
			    &ad);
}

2138
static int selinux_ptrace_access_check(struct task_struct *child,
2139
				     unsigned int mode)
L
Linus Torvalds 已提交
2140
{
2141 2142 2143 2144
	u32 sid = current_sid();
	u32 csid = task_sid(child);

	if (mode & PTRACE_MODE_READ)
2145
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2146

2147
	return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2148 2149 2150 2151
}

static int selinux_ptrace_traceme(struct task_struct *parent)
{
2152 2153
	return avc_has_perm(task_sid(parent), current_sid(), SECCLASS_PROCESS,
			    PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
2154 2155 2156
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2157
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
2158
{
2159 2160
	return avc_has_perm(current_sid(), task_sid(target), SECCLASS_PROCESS,
			    PROCESS__GETCAP, NULL);
L
Linus Torvalds 已提交
2161 2162
}

D
David Howells 已提交
2163 2164 2165 2166
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
2167
{
2168 2169
	return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
			    PROCESS__SETCAP, NULL);
L
Linus Torvalds 已提交
2170 2171
}

2172 2173 2174 2175 2176 2177 2178 2179 2180 2181
/*
 * (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.
 */

2182 2183
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
2184
{
2185
	return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
L
Linus Torvalds 已提交
2186 2187 2188 2189
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2190
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2191 2192 2193 2194 2195 2196
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2197 2198 2199 2200 2201
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2202
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2203 2204 2205 2206
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2207
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2208 2209 2210 2211
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2212 2213 2214 2215 2216 2217
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2218 2219
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2220
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2221 2222
}

2223
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2224 2225
{
	switch (type) {
2226 2227
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2228 2229
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2230 2231 2232 2233
	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:
2234 2235 2236
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
				    NULL);
L
Linus Torvalds 已提交
2237
	}
2238 2239 2240
	/* All other syslog types */
	return avc_has_perm(current_sid(), SECINITSID_KERNEL,
			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
L
Linus Torvalds 已提交
2241 2242 2243 2244 2245 2246 2247 2248 2249 2250
}

/*
 * 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.
 */
2251
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2252 2253 2254
{
	int rc, cap_sys_admin = 0;

C
Casey Schaufler 已提交
2255
	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2256
				 SECURITY_CAP_NOAUDIT, true);
L
Linus Torvalds 已提交
2257 2258 2259
	if (rc == 0)
		cap_sys_admin = 1;

C
Casey Schaufler 已提交
2260
	return cap_sys_admin;
L
Linus Torvalds 已提交
2261 2262 2263 2264
}

/* binprm security operations */

2265
static u32 ptrace_parent_sid(void)
2266 2267 2268 2269 2270
{
	u32 sid = 0;
	struct task_struct *tracer;

	rcu_read_lock();
2271
	tracer = ptrace_parent(current);
2272 2273 2274 2275 2276 2277 2278
	if (tracer)
		sid = task_sid(tracer);
	rcu_read_unlock();

	return sid;
}

2279 2280 2281 2282 2283
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);
2284
	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313
	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;
}

2314
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2315
{
2316 2317
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2318
	struct inode_security_struct *isec;
2319
	struct common_audit_data ad;
A
Al Viro 已提交
2320
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2321 2322
	int rc;

2323 2324 2325
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2326 2327
		return 0;

2328 2329
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
2330
	isec = inode_security(inode);
L
Linus Torvalds 已提交
2331 2332

	/* Default to the current task SID. */
2333 2334
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2335

2336
	/* Reset fs, key, and sock SIDs on execve. */
2337 2338 2339
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2340

2341 2342
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2343
		/* Reset exec SID on execve. */
2344
		new_tsec->exec_sid = 0;
2345

2346 2347 2348 2349
		/* 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
2350 2351
	} else {
		/* Check for a default transition on this program. */
2352
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2353 2354
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2355 2356
		if (rc)
			return rc;
2357 2358 2359 2360 2361 2362 2363 2364

		/*
		 * 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
2365 2366
	}

2367 2368
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = bprm->file;
L
Linus Torvalds 已提交
2369

2370 2371
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2372 2373 2374 2375 2376
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2377
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2378 2379 2380 2381
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2382
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2383 2384 2385 2386
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397
		/* 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 */
2398
		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2399
			u32 ptsid = ptrace_parent_sid();
2400 2401 2402 2403 2404 2405 2406 2407
			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
2408

2409 2410
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2411 2412 2413 2414 2415
	}

	return 0;
}

2416
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2417
{
2418
	const struct task_security_struct *tsec = current_security();
2419
	u32 sid, osid;
L
Linus Torvalds 已提交
2420 2421
	int atsecure = 0;

2422 2423 2424 2425
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2426 2427 2428
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2429
		atsecure = avc_has_perm(osid, sid,
2430 2431
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2432 2433
	}

C
Casey Schaufler 已提交
2434
	return !!atsecure;
L
Linus Torvalds 已提交
2435 2436
}

A
Al Viro 已提交
2437 2438 2439 2440 2441
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
2442
/* Derived from fs/exec.c:flush_old_files. */
2443 2444
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2445 2446
{
	struct file *file, *devnull = NULL;
2447
	struct tty_struct *tty;
2448
	int drop_tty = 0;
A
Al Viro 已提交
2449
	unsigned n;
L
Linus Torvalds 已提交
2450

2451
	tty = get_current_tty();
L
Linus Torvalds 已提交
2452
	if (tty) {
P
Peter Hurley 已提交
2453
		spin_lock(&tty->files_lock);
2454
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2455
			struct tty_file_private *file_priv;
2456

L
Linus Torvalds 已提交
2457
			/* Revalidate access to controlling tty.
2458 2459 2460 2461
			   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
2462 2463 2464
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2465
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2466
				drop_tty = 1;
L
Linus Torvalds 已提交
2467
		}
P
Peter Hurley 已提交
2468
		spin_unlock(&tty->files_lock);
A
Alan Cox 已提交
2469
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2470
	}
2471 2472 2473
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2474 2475

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2476 2477 2478
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2479

A
Al Viro 已提交
2480
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2481 2482 2483 2484 2485 2486 2487
	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
2488
		fput(devnull);
L
Linus Torvalds 已提交
2489 2490
}

2491 2492 2493 2494
/*
 * 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
2495
{
2496 2497 2498
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2499

2500 2501 2502
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2503

2504 2505
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2506

2507 2508
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2509

2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522
	/* 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) {
2523 2524
		/* protect against do_prlimit() */
		task_lock(current);
2525 2526 2527 2528
		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
2529
		}
2530
		task_unlock(current);
2531 2532
		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2533 2534 2535 2536
	}
}

/*
2537 2538
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2539
 */
2540
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2541
{
2542
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2543
	struct itimerval itimer;
2544
	u32 osid, sid;
L
Linus Torvalds 已提交
2545 2546
	int rc, i;

2547 2548 2549 2550
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2551 2552
		return;

2553 2554 2555 2556 2557 2558 2559 2560
	/* 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
2561
	if (rc) {
2562 2563 2564 2565 2566
		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
2567
		spin_lock_irq(&current->sighand->siglock);
2568 2569 2570
		if (!fatal_signal_pending(current)) {
			flush_sigqueue(&current->pending);
			flush_sigqueue(&current->signal->shared_pending);
2571 2572
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
2573
			recalc_sigpending();
2574
		}
L
Linus Torvalds 已提交
2575 2576 2577
		spin_unlock_irq(&current->sighand->siglock);
	}

2578 2579
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2580
	read_lock(&tasklist_lock);
2581
	__wake_up_parent(current, current->real_parent);
2582
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606
}

/* 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)
{
2607 2608 2609
	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) ||
2610 2611
		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
2612 2613 2614 2615 2616 2617 2618
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2619
	} else
L
Linus Torvalds 已提交
2620 2621 2622 2623 2624
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2625 2626
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2627 2628 2629 2630 2631 2632
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2633
	} else
2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645
		*first = 0;

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

2646
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2647 2648 2649 2650
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2651
	int open_quote = 0;
L
Linus Torvalds 已提交
2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666

	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 {
2667 2668 2669 2670
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2671 2672 2673
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2674
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2675 2676 2677 2678 2679 2680 2681
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2682
	strcpy(in_save, nosec_save);
2683
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2684 2685 2686 2687
out:
	return rc;
}

2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721
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;

2722
		if (flags[i] == SBLABEL_MNT)
2723
			continue;
2724
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2725
		if (rc) {
2726
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2727 2728
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742
			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;
2743
			root_isec = backing_inode_security(sb->s_root);
2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765

			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 "
2766 2767
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2768 2769 2770
	goto out_free_opts;
}

2771
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2772
{
2773
	const struct cred *cred = current_cred();
2774
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2775 2776 2777 2778 2779 2780
	int rc;

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

2781 2782 2783 2784
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2785
	ad.type = LSM_AUDIT_DATA_DENTRY;
2786
	ad.u.dentry = sb->s_root;
2787
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2788 2789
}

2790
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2791
{
2792
	const struct cred *cred = current_cred();
2793
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2794

2795
	ad.type = LSM_AUDIT_DATA_DENTRY;
2796
	ad.u.dentry = dentry->d_sb->s_root;
2797
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2798 2799
}

A
Al Viro 已提交
2800
static int selinux_mount(const char *dev_name,
A
Al Viro 已提交
2801
			 const struct path *path,
A
Al Viro 已提交
2802
			 const char *type,
2803 2804
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2805
{
2806
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2807 2808

	if (flags & MS_REMOUNT)
2809
		return superblock_has_perm(cred, path->dentry->d_sb,
2810
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2811
	else
E
Eric Paris 已提交
2812
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2813 2814 2815 2816
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2817
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2818

2819
	return superblock_has_perm(cred, mnt->mnt_sb,
2820
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834
}

/* 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);
}

2835
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
A
Al Viro 已提交
2836
					const struct qstr *name, void **ctx,
2837 2838 2839 2840 2841
					u32 *ctxlen)
{
	u32 newsid;
	int rc;

2842 2843
	rc = selinux_determine_inode_label(current_security(),
					   d_inode(dentry->d_parent), name,
2844 2845 2846 2847
					   inode_mode_to_security_class(mode),
					   &newsid);
	if (rc)
		return rc;
2848 2849 2850 2851

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

2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872
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;
}

2873
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2874 2875
				       const struct qstr *qstr,
				       const char **name,
2876
				       void **value, size_t *len)
2877
{
2878
	const struct task_security_struct *tsec = current_security();
2879
	struct superblock_security_struct *sbsec;
2880
	u32 sid, newsid, clen;
2881
	int rc;
2882
	char *context;
2883 2884 2885

	sbsec = dir->i_sb->s_security;

2886 2887 2888
	sid = tsec->sid;
	newsid = tsec->create_sid;

2889
	rc = selinux_determine_inode_label(current_security(),
2890 2891 2892 2893 2894
		dir, qstr,
		inode_mode_to_security_class(inode->i_mode),
		&newsid);
	if (rc)
		return rc;
2895

2896
	/* Possibly defer initialization to selinux_complete_init. */
2897
	if (sbsec->flags & SE_SBINITIALIZED) {
2898 2899 2900
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
2901
		isec->initialized = LABEL_INITIALIZED;
2902
	}
2903

2904
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2905 2906
		return -EOPNOTSUPP;

2907 2908
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2909

2910
	if (value && len) {
2911
		rc = security_sid_to_context_force(newsid, &context, &clen);
2912
		if (rc)
2913 2914 2915
			return rc;
		*value = context;
		*len = clen;
2916 2917 2918 2919 2920
	}

	return 0;
}

A
Al Viro 已提交
2921
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940
{
	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);
}

2941
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2942 2943 2944 2945 2946 2947 2948 2949 2950
{
	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
2951
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2952 2953 2954 2955 2956
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2957
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2958 2959 2960 2961 2962 2963
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2964 2965
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2966
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2967 2968
}

2969 2970
static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
				     bool rcu)
L
Linus Torvalds 已提交
2971
{
2972
	const struct cred *cred = current_cred();
2973 2974 2975
	struct common_audit_data ad;
	struct inode_security_struct *isec;
	u32 sid;
L
Linus Torvalds 已提交
2976

2977 2978 2979 2980 2981
	validate_creds(cred);

	ad.type = LSM_AUDIT_DATA_DENTRY;
	ad.u.dentry = dentry;
	sid = cred_sid(cred);
2982 2983 2984
	isec = inode_security_rcu(inode, rcu);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
2985 2986 2987

	return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
				  rcu ? MAY_NOT_BLOCK : 0);
L
Linus Torvalds 已提交
2988 2989
}

2990 2991
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
2992
					   int result,
2993
					   unsigned flags)
L
Linus Torvalds 已提交
2994
{
2995
	struct common_audit_data ad;
2996 2997 2998
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2999
	ad.type = LSM_AUDIT_DATA_INODE;
3000 3001 3002
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3003
			    audited, denied, result, &ad, flags);
3004 3005 3006 3007 3008
	if (rc)
		return rc;
	return 0;
}

3009
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
3010
{
3011
	const struct cred *cred = current_cred();
3012 3013
	u32 perms;
	bool from_access;
3014
	unsigned flags = mask & MAY_NOT_BLOCK;
3015 3016 3017 3018 3019
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
3020

3021
	from_access = mask & MAY_ACCESS;
3022 3023
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

3024 3025
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
3026 3027
		return 0;

3028
	validate_creds(cred);
3029

3030 3031
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
3032 3033 3034

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

3035
	sid = cred_sid(cred);
3036 3037 3038
	isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
3039 3040 3041 3042 3043 3044 3045 3046

	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;

3047
	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3048 3049 3050
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
3051 3052 3053 3054
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
3055
	const struct cred *cred = current_cred();
3056
	struct inode *inode = d_backing_inode(dentry);
3057
	unsigned int ia_valid = iattr->ia_valid;
3058
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
3059

3060 3061 3062 3063 3064 3065 3066
	/* 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
3067

3068 3069
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
3070
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
3071

3072 3073 3074 3075
	if (selinux_policycap_openperm &&
	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
	    (ia_valid & ATTR_SIZE) &&
	    !(ia_valid & ATTR_FILE))
3076 3077 3078
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
3079 3080
}

3081
static int selinux_inode_getattr(const struct path *path)
L
Linus Torvalds 已提交
3082
{
3083
	return path_has_perm(current_cred(), path, FILE__GETATTR);
L
Linus Torvalds 已提交
3084 3085
}

3086
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3087
{
3088 3089
	const struct cred *cred = current_cred();

3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103
	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
3104
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
3105 3106
}

3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118
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;
}

3119 3120
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
3121
{
3122
	struct inode *inode = d_backing_inode(dentry);
3123
	struct inode_security_struct *isec;
L
Linus Torvalds 已提交
3124
	struct superblock_security_struct *sbsec;
3125
	struct common_audit_data ad;
3126
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
3127 3128
	int rc = 0;

3129 3130
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3131 3132

	sbsec = inode->i_sb->s_security;
3133
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
3134 3135
		return -EOPNOTSUPP;

3136
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
3137 3138
		return -EPERM;

3139
	ad.type = LSM_AUDIT_DATA_DENTRY;
3140
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
3141

3142
	isec = backing_inode_security(dentry);
3143
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
3144 3145 3146 3147
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

3148
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3149
	if (rc == -EINVAL) {
3150
		if (!has_cap_mac_admin(true)) {
3151 3152 3153 3154 3155 3156
			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 */
3157 3158 3159 3160 3161 3162 3163 3164 3165 3166
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
3167 3168 3169 3170 3171
			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);

3172
			return rc;
3173
		}
3174 3175
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
3176 3177 3178
	if (rc)
		return rc;

3179
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
3180 3181 3182 3183
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

3184
	rc = security_validate_transition(isec->sid, newsid, sid,
3185
					  isec->sclass);
L
Linus Torvalds 已提交
3186 3187 3188 3189 3190 3191 3192 3193 3194 3195
	if (rc)
		return rc;

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

3196
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3197
					const void *value, size_t size,
3198
					int flags)
L
Linus Torvalds 已提交
3199
{
3200
	struct inode *inode = d_backing_inode(dentry);
3201
	struct inode_security_struct *isec;
L
Linus Torvalds 已提交
3202 3203 3204 3205 3206 3207 3208 3209
	u32 newsid;
	int rc;

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

3210
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
3211
	if (rc) {
3212 3213 3214
		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
3215 3216 3217
		return;
	}

3218
	isec = backing_inode_security(dentry);
3219
	spin_lock(&isec->lock);
3220
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3221
	isec->sid = newsid;
3222
	isec->initialized = LABEL_INITIALIZED;
3223
	spin_unlock(&isec->lock);
3224

L
Linus Torvalds 已提交
3225 3226 3227
	return;
}

3228
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3229
{
3230 3231
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3232
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3233 3234
}

3235
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
3236
{
3237 3238
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3239
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3240 3241
}

3242
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3243
{
3244 3245
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3246 3247 3248 3249 3250 3251

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

3252
/*
3253
 * Copy the inode security context value to the user.
3254 3255 3256
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
3257
static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
3258
{
3259 3260 3261
	u32 size;
	int error;
	char *context = NULL;
3262
	struct inode_security_struct *isec;
3263

3264 3265
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3266

3267 3268 3269 3270 3271 3272 3273 3274 3275
	/*
	 * 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.
	 */
3276
	isec = inode_security(inode);
3277
	if (has_cap_mac_admin(false))
3278 3279 3280 3281
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3282 3283 3284 3285 3286 3287 3288 3289 3290 3291
	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
3292 3293 3294
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3295
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3296
{
3297
	struct inode_security_struct *isec = inode_security_novalidate(inode);
L
Linus Torvalds 已提交
3298 3299 3300 3301 3302 3303 3304 3305 3306
	u32 newsid;
	int rc;

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

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

3307
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
L
Linus Torvalds 已提交
3308 3309 3310
	if (rc)
		return rc;

3311
	spin_lock(&isec->lock);
3312
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3313
	isec->sid = newsid;
3314
	isec->initialized = LABEL_INITIALIZED;
3315
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326
	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;
}

3327
static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3328
{
3329
	struct inode_security_struct *isec = inode_security_novalidate(inode);
3330 3331 3332
	*secid = isec->sid;
}

3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352
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;
}

3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367
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
3368 3369
/* file security operations */

3370
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3371
{
3372
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3373
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3374 3375 3376 3377 3378

	/* 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;

3379 3380
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3381 3382
}

3383 3384
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3385
	struct inode *inode = file_inode(file);
3386
	struct file_security_struct *fsec = file->f_security;
3387
	struct inode_security_struct *isec;
3388 3389
	u32 sid = current_sid();

3390
	if (!mask)
3391 3392 3393
		/* No permission to check.  Existence test. */
		return 0;

3394
	isec = inode_security(inode);
3395 3396
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3397
		/* No change since file_open check. */
3398 3399
		return 0;

3400 3401 3402
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3403 3404 3405 3406 3407 3408 3409 3410 3411 3412
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);
}

3413 3414 3415 3416
/*
 * Check whether a task has the ioctl permission and cmd
 * operation to an inode.
 */
3417
static int ioctl_has_perm(const struct cred *cred, struct file *file,
3418 3419 3420 3421 3422
		u32 requested, u16 cmd)
{
	struct common_audit_data ad;
	struct file_security_struct *fsec = file->f_security;
	struct inode *inode = file_inode(file);
3423
	struct inode_security_struct *isec;
3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446
	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;

3447
	isec = inode_security(inode);
3448 3449 3450 3451 3452 3453
	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
			requested, driver, xperm, &ad);
out:
	return rc;
}

L
Linus Torvalds 已提交
3454 3455 3456
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3457
	const struct cred *cred = current_cred();
3458
	int error = 0;
L
Linus Torvalds 已提交
3459

3460 3461 3462 3463 3464 3465 3466
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3467
	case FS_IOC_GETFLAGS:
3468
	/* fall through */
3469
	case FS_IOC_GETVERSION:
3470 3471
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3472

3473
	case FS_IOC_SETFLAGS:
3474
	/* fall through */
3475
	case FS_IOC_SETVERSION:
3476 3477 3478 3479 3480 3481 3482 3483 3484
		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
3485

3486 3487
	case KDSKBENT:
	case KDSKBSENT:
3488
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3489
					    SECURITY_CAP_AUDIT, true);
3490 3491 3492 3493 3494 3495
		break;

	/* default case assumes that the command will go
	 * to the file's ioctl() function.
	 */
	default:
3496
		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3497 3498
	}
	return error;
L
Linus Torvalds 已提交
3499 3500
}

3501 3502
static int default_noexec;

L
Linus Torvalds 已提交
3503 3504
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3505
	const struct cred *cred = current_cred();
3506
	u32 sid = cred_sid(cred);
D
David Howells 已提交
3507
	int rc = 0;
3508

3509
	if (default_noexec &&
3510 3511
	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
				   (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3512 3513 3514 3515 3516
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
3517 3518
		rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
				  PROCESS__EXECMEM, NULL);
L
Linus Torvalds 已提交
3519
		if (rc)
D
David Howells 已提交
3520
			goto error;
L
Linus Torvalds 已提交
3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533
	}

	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;

3534
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3535
	}
D
David Howells 已提交
3536 3537 3538

error:
	return rc;
L
Linus Torvalds 已提交
3539 3540
}

3541
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3542
{
C
Casey Schaufler 已提交
3543
	int rc = 0;
L
Linus Torvalds 已提交
3544

3545
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3546
		u32 sid = current_sid();
3547 3548
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3549 3550
	}

3551
	return rc;
3552
}
L
Linus Torvalds 已提交
3553

3554 3555 3556
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568
	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
3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579
	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)
{
3580
	const struct cred *cred = current_cred();
3581
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
3582 3583 3584 3585

	if (selinux_checkreqprot)
		prot = reqprot;

3586 3587
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3588
		int rc = 0;
3589 3590
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
3591 3592
			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
					  PROCESS__EXECHEAP, NULL);
3593
		} else if (!vma->vm_file &&
3594 3595
			   ((vma->vm_start <= vma->vm_mm->start_stack &&
			     vma->vm_end >= vma->vm_mm->start_stack) ||
3596
			    vma_is_stack_for_current(vma))) {
3597 3598
			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
					  PROCESS__EXECSTACK, NULL);
3599 3600 3601 3602 3603 3604 3605 3606
		} 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
3607
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3608
		}
3609 3610 3611
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3612 3613 3614 3615 3616 3617

	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)
{
3618 3619 3620
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3621 3622 3623 3624 3625
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3626
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3627 3628 3629
	int err = 0;

	switch (cmd) {
3630 3631
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3632
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3633
			break;
3634 3635 3636 3637 3638 3639 3640
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3641
	case F_GETOWNER_UIDS:
3642
		/* Just check FD__USE permission */
3643
		err = file_has_perm(cred, file, 0);
3644 3645 3646 3647
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
3648 3649 3650
	case F_OFD_GETLK:
	case F_OFD_SETLK:
	case F_OFD_SETLKW:
L
Linus Torvalds 已提交
3651
#if BITS_PER_LONG == 32
3652 3653 3654
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3655
#endif
3656
		err = file_has_perm(cred, file, FILE__LOCK);
3657
		break;
L
Linus Torvalds 已提交
3658 3659 3660 3661 3662
	}

	return err;
}

3663
static void selinux_file_set_fowner(struct file *file)
L
Linus Torvalds 已提交
3664 3665 3666 3667
{
	struct file_security_struct *fsec;

	fsec = file->f_security;
3668
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3669 3670 3671 3672 3673
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3674
	struct file *file;
3675
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3676 3677 3678 3679
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3680
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3681 3682 3683 3684 3685 3686 3687 3688

	fsec = file->f_security;

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

3689
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3690 3691 3692 3693 3694
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3695 3696 3697
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3698 3699
}

3700
static int selinux_file_open(struct file *file, const struct cred *cred)
3701 3702 3703
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3704

3705
	fsec = file->f_security;
3706
	isec = inode_security(file_inode(file));
3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723
	/*
	 * 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.
	 */
3724
	return file_path_has_perm(cred, file, open_file_to_av(file));
3725 3726
}

L
Linus Torvalds 已提交
3727 3728
/* task security operations */

3729 3730
static int selinux_task_alloc(struct task_struct *task,
			      unsigned long clone_flags)
L
Linus Torvalds 已提交
3731
{
3732 3733 3734
	u32 sid = current_sid();

	return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
L
Linus Torvalds 已提交
3735 3736
}

3737 3738 3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751
/*
 * 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
3752 3753 3754 3755
/*
 * 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
3756
{
D
David Howells 已提交
3757
	struct task_security_struct *tsec = cred->security;
3758

3759 3760 3761 3762 3763
	/*
	 * 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);
3764
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3765 3766
	kfree(tsec);
}
L
Linus Torvalds 已提交
3767

D
David Howells 已提交
3768 3769 3770 3771 3772 3773 3774 3775
/*
 * 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
3776

D
David Howells 已提交
3777
	old_tsec = old->security;
L
Linus Torvalds 已提交
3778

D
David Howells 已提交
3779 3780 3781
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3782

D
David Howells 已提交
3783
	new->security = tsec;
L
Linus Torvalds 已提交
3784 3785 3786
	return 0;
}

3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797
/*
 * 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;
}

3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826
/*
 * 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)
{
3827
	struct inode_security_struct *isec = inode_security(inode);
3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838
	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;
3839
	return ret;
3840 3841
}

3842
static int selinux_kernel_module_request(char *kmod_name)
3843
{
3844 3845
	struct common_audit_data ad;

3846
	ad.type = LSM_AUDIT_DATA_KMOD;
3847 3848
	ad.u.kmod_name = kmod_name;

3849
	return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3850
			    SYSTEM__MODULE_REQUEST, &ad);
3851 3852
}

3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866
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 */
3867

3868 3869
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
3870 3871 3872 3873 3874 3875 3876 3877

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

3878
	isec = inode_security(file_inode(file));
3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898
	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
3899 3900
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3901 3902
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETPGID, NULL);
L
Linus Torvalds 已提交
3903 3904 3905 3906
}

static int selinux_task_getpgid(struct task_struct *p)
{
3907 3908
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETPGID, NULL);
L
Linus Torvalds 已提交
3909 3910 3911 3912
}

static int selinux_task_getsid(struct task_struct *p)
{
3913 3914
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSESSION, NULL);
L
Linus Torvalds 已提交
3915 3916
}

3917 3918
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3919
	*secid = task_sid(p);
3920 3921
}

L
Linus Torvalds 已提交
3922 3923
static int selinux_task_setnice(struct task_struct *p, int nice)
{
3924 3925
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
L
Linus Torvalds 已提交
3926 3927
}

3928 3929
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3930 3931
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
3932 3933
}

3934 3935
static int selinux_task_getioprio(struct task_struct *p)
{
3936 3937
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSCHED, NULL);
3938 3939
}

3940 3941 3942 3943 3944
int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
			 unsigned int flags)
{
	u32 av = 0;

3945 3946
	if (!flags)
		return 0;
3947 3948 3949 3950 3951 3952 3953 3954
	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);
}

3955 3956
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3957
{
3958
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3959 3960 3961 3962

	/* 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
3963
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3964
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3965 3966
		return avc_has_perm(current_sid(), task_sid(p),
				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
L
Linus Torvalds 已提交
3967 3968 3969 3970

	return 0;
}

3971
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3972
{
3973 3974
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
L
Linus Torvalds 已提交
3975 3976 3977 3978
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3979 3980
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSCHED, NULL);
L
Linus Torvalds 已提交
3981 3982
}

3983 3984
static int selinux_task_movememory(struct task_struct *p)
{
3985 3986
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
3987 3988
}

3989 3990
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3991 3992 3993 3994 3995 3996 3997
{
	u32 perm;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3998 3999 4000
	if (!secid)
		secid = current_sid();
	return avc_has_perm(secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
L
Linus Torvalds 已提交
4001 4002 4003 4004 4005 4006
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
4007
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
4008

4009
	spin_lock(&isec->lock);
4010
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4011
	isec->sid = sid;
4012
	isec->initialized = LABEL_INITIALIZED;
4013
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
4014 4015 4016
}

/* Returns error only if unable to parse addresses */
4017
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4018
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
4019 4020 4021 4022
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

4023
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
4024 4025 4026 4027 4028 4029 4030 4031
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

4032 4033
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
4034 4035
	ret = 0;

4036 4037 4038
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
4039
	switch (ih->protocol) {
4040 4041
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
4042

4043 4044
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
4045 4046 4047 4048 4049 4050

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

4051 4052
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
4053
		break;
4054 4055 4056 4057 4058 4059 4060 4061
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
4062
		offset += ihlen;
4063
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
4064
		if (uh == NULL)
4065
			break;
L
Linus Torvalds 已提交
4066

4067 4068
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
4069 4070
		break;
	}
L
Linus Torvalds 已提交
4071

J
James Morris 已提交
4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082
	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;

4083 4084
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
4085
		break;
4086
	}
J
James Morris 已提交
4087

4088 4089 4090
	default:
		break;
	}
L
Linus Torvalds 已提交
4091 4092 4093 4094
out:
	return ret;
}

4095
#if IS_ENABLED(CONFIG_IPV6)
L
Linus Torvalds 已提交
4096 4097

/* Returns error only if unable to parse addresses */
4098
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4099
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
4100 4101 4102 4103
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
4104
	__be16 frag_off;
L
Linus Torvalds 已提交
4105

4106
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
4107 4108 4109 4110
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

4111 4112
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
4113 4114 4115 4116
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
4117
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
4118 4119 4120
	if (offset < 0)
		goto out;

4121 4122 4123
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
4124 4125
	switch (nexthdr) {
	case IPPROTO_TCP: {
4126
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
4127 4128 4129 4130 4131

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

4132 4133
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
4134 4135 4136 4137 4138 4139 4140 4141 4142 4143
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

4144 4145
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
4146 4147 4148
		break;
	}

J
James Morris 已提交
4149 4150 4151 4152 4153 4154 4155
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

4156 4157
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
4158
		break;
4159
	}
J
James Morris 已提交
4160

L
Linus Torvalds 已提交
4161 4162 4163 4164 4165 4166 4167 4168 4169 4170
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

4171
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4172
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
4173
{
4174 4175
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
4176

4177
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
4178
	case PF_INET:
4179
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4180 4181
		if (ret)
			goto parse_error;
4182 4183
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
4184
		goto okay;
L
Linus Torvalds 已提交
4185

4186
#if IS_ENABLED(CONFIG_IPV6)
L
Linus Torvalds 已提交
4187
	case PF_INET6:
4188
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4189 4190
		if (ret)
			goto parse_error;
4191 4192
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
4193
		goto okay;
L
Linus Torvalds 已提交
4194 4195
#endif	/* IPV6 */
	default:
4196 4197
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
4198 4199
	}

4200 4201 4202 4203
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
4204
	return ret;
4205 4206 4207 4208 4209

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
4210 4211
}

4212
/**
4213
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4214
 * @skb: the packet
4215
 * @family: protocol family
4216
 * @sid: the packet's peer label SID
4217 4218
 *
 * Description:
4219 4220 4221 4222 4223 4224
 * 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.
4225 4226
 *
 */
4227
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4228
{
4229
	int err;
4230 4231
	u32 xfrm_sid;
	u32 nlbl_sid;
4232
	u32 nlbl_type;
4233

4234
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4235 4236 4237 4238 4239
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
4240

4241 4242 4243 4244 4245
	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");
4246
		return -EACCES;
4247
	}
4248 4249

	return 0;
4250 4251
}

4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275
/**
 * 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
4276
/* socket security operations */
4277

4278 4279
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
4280
{
4281 4282 4283 4284 4285 4286 4287
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
4288 4289
}

4290
static int sock_has_perm(struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
4291
{
4292
	struct sk_security_struct *sksec = sk->sk_security;
4293
	struct common_audit_data ad;
4294
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4295

4296 4297
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
4298

4299
	ad.type = LSM_AUDIT_DATA_NET;
4300 4301
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
4302

4303 4304
	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
			    &ad);
L
Linus Torvalds 已提交
4305 4306 4307 4308 4309
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
4310
	const struct task_security_struct *tsec = current_security();
4311
	u32 newsid;
4312
	u16 secclass;
4313
	int rc;
L
Linus Torvalds 已提交
4314 4315

	if (kern)
4316
		return 0;
4317 4318

	secclass = socket_type_to_security_class(family, type, protocol);
4319 4320 4321 4322
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

4323
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
4324 4325
}

V
Venkat Yekkirala 已提交
4326 4327
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
4328
{
4329
	const struct task_security_struct *tsec = current_security();
4330
	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4331
	struct sk_security_struct *sksec;
4332 4333
	u16 sclass = socket_type_to_security_class(family, type, protocol);
	u32 sid = SECINITSID_KERNEL;
4334 4335
	int err = 0;

4336 4337
	if (!kern) {
		err = socket_sockcreate_sid(tsec, sclass, &sid);
4338 4339 4340
		if (err)
			return err;
	}
4341

4342 4343
	isec->sclass = sclass;
	isec->sid = sid;
4344
	isec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4345

4346 4347
	if (sock->sk) {
		sksec = sock->sk->sk_security;
4348 4349
		sksec->sclass = sclass;
		sksec->sid = sid;
4350
		err = selinux_netlbl_socket_post_create(sock->sk, family);
4351 4352
	}

V
Venkat Yekkirala 已提交
4353
	return err;
L
Linus Torvalds 已提交
4354 4355 4356 4357 4358 4359 4360 4361
}

/* 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)
{
4362
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
4363 4364 4365
	u16 family;
	int err;

4366
	err = sock_has_perm(sk, SOCKET__BIND);
L
Linus Torvalds 已提交
4367 4368 4369 4370 4371
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
4372 4373
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
4374
	 */
4375
	family = sk->sk_family;
L
Linus Torvalds 已提交
4376 4377
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
4378
		struct sk_security_struct *sksec = sk->sk_security;
4379
		struct common_audit_data ad;
4380
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4381 4382 4383
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
4384
		u32 sid, node_perm;
L
Linus Torvalds 已提交
4385 4386

		if (family == PF_INET) {
4387 4388 4389 4390
			if (addrlen < sizeof(struct sockaddr_in)) {
				err = -EINVAL;
				goto out;
			}
L
Linus Torvalds 已提交
4391 4392 4393 4394
			addr4 = (struct sockaddr_in *)address;
			snum = ntohs(addr4->sin_port);
			addrp = (char *)&addr4->sin_addr.s_addr;
		} else {
4395 4396 4397 4398
			if (addrlen < SIN6_LEN_RFC2133) {
				err = -EINVAL;
				goto out;
			}
L
Linus Torvalds 已提交
4399 4400 4401 4402 4403
			addr6 = (struct sockaddr_in6 *)address;
			snum = ntohs(addr6->sin6_port);
			addrp = (char *)&addr6->sin6_addr.s6_addr;
		}

4404 4405 4406
		if (snum) {
			int low, high;

4407
			inet_get_local_port_range(sock_net(sk), &low, &high);
4408

4409 4410
			if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
			    snum > high) {
P
Paul Moore 已提交
4411 4412
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4413 4414
				if (err)
					goto out;
4415
				ad.type = LSM_AUDIT_DATA_NET;
4416 4417 4418
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4419 4420
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4421 4422 4423 4424
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4425
		}
4426

4427
		switch (sksec->sclass) {
4428
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4429 4430
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4431

4432
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4433 4434
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4435 4436 4437 4438 4439

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4440 4441 4442 4443
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4444

4445
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4446 4447
		if (err)
			goto out;
4448

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;
L
Linus Torvalds 已提交
4453 4454

		if (family == PF_INET)
4455
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4456
		else
4457
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4458

4459 4460
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4461 4462 4463 4464 4465 4466 4467 4468 4469
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4470
	struct sock *sk = sock->sk;
4471
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4472 4473
	int err;

4474
	err = sock_has_perm(sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4475 4476 4477 4478
	if (err)
		return err;

	/*
J
James Morris 已提交
4479
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4480
	 */
4481 4482
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4483
		struct common_audit_data ad;
4484
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4485 4486 4487
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4488
		u32 sid, perm;
L
Linus Torvalds 已提交
4489 4490 4491

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4492
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4493 4494 4495 4496
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4497
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4498 4499 4500 4501
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4502
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4503 4504 4505
		if (err)
			goto out;

4506
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4507 4508
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4509
		ad.type = LSM_AUDIT_DATA_NET;
4510 4511 4512
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4513
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4514 4515 4516 4517
		if (err)
			goto out;
	}

4518 4519
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4520 4521 4522 4523 4524 4525
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4526
	return sock_has_perm(sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4527 4528 4529 4530 4531 4532 4533
}

static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
{
	int err;
	struct inode_security_struct *isec;
	struct inode_security_struct *newisec;
4534 4535
	u16 sclass;
	u32 sid;
L
Linus Torvalds 已提交
4536

4537
	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4538 4539 4540
	if (err)
		return err;

4541
	isec = inode_security_novalidate(SOCK_INODE(sock));
4542 4543 4544 4545 4546 4547 4548 4549
	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;
4550
	newisec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4551 4552 4553 4554 4555

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4556
				  int size)
L
Linus Torvalds 已提交
4557
{
4558
	return sock_has_perm(sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4559 4560 4561 4562 4563
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4564
	return sock_has_perm(sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4565 4566 4567 4568
}

static int selinux_socket_getsockname(struct socket *sock)
{
4569
	return sock_has_perm(sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4570 4571 4572 4573
}

static int selinux_socket_getpeername(struct socket *sock)
{
4574
	return sock_has_perm(sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4575 4576
}

4577
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4578
{
4579 4580
	int err;

4581
	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4582 4583 4584 4585
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4586 4587 4588 4589 4590
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4591
	return sock_has_perm(sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4592 4593 4594 4595
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4596
	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4597 4598
}

4599 4600
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4601 4602
					      struct sock *newsk)
{
4603 4604
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4605
	struct sk_security_struct *sksec_new = newsk->sk_security;
4606
	struct common_audit_data ad;
4607
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4608 4609
	int err;

4610
	ad.type = LSM_AUDIT_DATA_NET;
4611 4612
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4613

4614 4615
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4616 4617 4618 4619 4620
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4621 4622 4623 4624 4625
	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;
4626

4627 4628 4629 4630
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4631 4632 4633 4634 4635
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4636 4637
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4638
	struct common_audit_data ad;
4639
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4640

4641
	ad.type = LSM_AUDIT_DATA_NET;
4642 4643
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4644

4645 4646
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4647 4648
}

4649 4650
static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
				    char *addrp, u16 family, u32 peer_sid,
4651
				    struct common_audit_data *ad)
4652 4653 4654 4655 4656
{
	int err;
	u32 if_sid;
	u32 node_sid;

4657
	err = sel_netif_sid(ns, ifindex, &if_sid);
4658 4659 4660 4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 4671
	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);
}

4672
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4673
				       u16 family)
4674
{
4675
	int err = 0;
4676 4677
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4678
	struct common_audit_data ad;
4679
	struct lsm_network_audit net = {0,};
4680 4681
	char *addrp;

4682
	ad.type = LSM_AUDIT_DATA_NET;
4683 4684 4685
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4686 4687 4688
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4689

4690
	if (selinux_secmark_enabled()) {
4691
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4692
				   PACKET__RECV, &ad);
4693 4694 4695
		if (err)
			return err;
	}
4696

4697 4698 4699 4700
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4701

4702 4703 4704 4705 4706
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4707
	int err;
4708
	struct sk_security_struct *sksec = sk->sk_security;
4709 4710
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4711
	struct common_audit_data ad;
4712
	struct lsm_network_audit net = {0,};
4713
	char *addrp;
4714 4715
	u8 secmark_active;
	u8 peerlbl_active;
4716 4717

	if (family != PF_INET && family != PF_INET6)
4718
		return 0;
4719 4720

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4721
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4722 4723
		family = PF_INET;

4724 4725 4726 4727
	/* 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. */
4728
	if (!selinux_policycap_netpeer)
4729 4730 4731
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4732
	peerlbl_active = selinux_peerlbl_enabled();
4733 4734 4735
	if (!secmark_active && !peerlbl_active)
		return 0;

4736
	ad.type = LSM_AUDIT_DATA_NET;
4737 4738 4739
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4740
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4741
	if (err)
4742
		return err;
4743

4744
	if (peerlbl_active) {
4745 4746 4747
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4748 4749
		if (err)
			return err;
4750 4751
		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
					       addrp, family, peer_sid, &ad);
4752
		if (err) {
4753
			selinux_netlbl_err(skb, family, err, 0);
4754
			return err;
4755
		}
4756 4757
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4758
		if (err) {
4759
			selinux_netlbl_err(skb, family, err, 0);
C
Chad Hanson 已提交
4760 4761
			return err;
		}
4762 4763
	}

4764
	if (secmark_active) {
4765 4766 4767 4768 4769 4770
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4771
	return err;
L
Linus Torvalds 已提交
4772 4773
}

C
Catherine Zhang 已提交
4774 4775
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4776 4777 4778 4779
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4780
	struct sk_security_struct *sksec = sock->sk->sk_security;
4781
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4782

4783 4784
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4785
		peer_sid = sksec->peer_sid;
4786 4787
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4788

C
Catherine Zhang 已提交
4789
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4790
	if (err)
4791
		return err;
L
Linus Torvalds 已提交
4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807

	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;
}

4808
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4809
{
4810
	u32 peer_secid = SECSID_NULL;
4811
	u16 family;
4812
	struct inode_security_struct *isec;
C
Catherine Zhang 已提交
4813

4814 4815 4816 4817 4818
	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)
4819 4820 4821 4822
		family = sock->sk->sk_family;
	else
		goto out;

4823 4824 4825 4826
	if (sock && family == PF_UNIX) {
		isec = inode_security_novalidate(SOCK_INODE(sock));
		peer_secid = isec->sid;
	} else if (skb)
4827
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4828

4829
out:
4830
	*secid = peer_secid;
4831 4832 4833
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4834 4835
}

A
Al Viro 已提交
4836
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4837
{
4838 4839 4840 4841 4842 4843 4844 4845
	struct sk_security_struct *sksec;

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

	sksec->peer_sid = SECINITSID_UNLABELED;
	sksec->sid = SECINITSID_UNLABELED;
4846
	sksec->sclass = SECCLASS_SOCKET;
4847 4848 4849 4850
	selinux_netlbl_sk_security_reset(sksec);
	sk->sk_security = sksec;

	return 0;
L
Linus Torvalds 已提交
4851 4852 4853 4854
}

static void selinux_sk_free_security(struct sock *sk)
{
4855 4856 4857 4858 4859
	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
4860 4861
}

4862
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4863
{
4864 4865
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4866

4867 4868 4869
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4870

4871
	selinux_netlbl_sk_security_reset(newsksec);
4872 4873
}

V
Venkat Yekkirala 已提交
4874
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4875
{
4876
	if (!sk)
V
Venkat Yekkirala 已提交
4877
		*secid = SECINITSID_ANY_SOCKET;
4878 4879
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4880

V
Venkat Yekkirala 已提交
4881
		*secid = sksec->sid;
4882
	}
4883 4884
}

4885
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4886
{
4887 4888
	struct inode_security_struct *isec =
		inode_security_novalidate(SOCK_INODE(parent));
4889 4890
	struct sk_security_struct *sksec = sk->sk_security;

4891 4892
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
4893
		isec->sid = sksec->sid;
4894
	sksec->sclass = isec->sclass;
4895 4896
}

4897 4898
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4899 4900 4901
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4902
	u16 family = req->rsk_ops->family;
4903
	u32 connsid;
4904 4905
	u32 peersid;

4906
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4907 4908
	if (err)
		return err;
4909 4910 4911 4912 4913
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4914

4915
	return selinux_netlbl_inet_conn_request(req, family);
4916 4917
}

4918 4919
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4920 4921 4922 4923
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4924
	newsksec->peer_sid = req->peer_secid;
4925 4926 4927 4928
	/* 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. */
4929

P
Paul Moore 已提交
4930 4931
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4932
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4933 4934
}

4935
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4936
{
4937
	u16 family = sk->sk_family;
4938 4939
	struct sk_security_struct *sksec = sk->sk_security;

4940 4941 4942 4943 4944
	/* 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);
4945 4946
}

4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967
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);
}

4968 4969
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4970
{
4971
	fl->flowi_secid = req->secid;
4972 4973
}

4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991
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);
}

4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006
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);
}

5007
static int selinux_tun_dev_attach_queue(void *security)
5008
{
5009 5010 5011 5012 5013 5014 5015 5016 5017
	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;
5018 5019 5020 5021 5022 5023 5024 5025 5026
	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 */

5027
	sksec->sid = tunsec->sid;
5028
	sksec->sclass = SECCLASS_TUN_SOCKET;
5029 5030

	return 0;
5031 5032
}

5033
static int selinux_tun_dev_open(void *security)
5034
{
5035
	struct tun_security_struct *tunsec = security;
5036 5037 5038
	u32 sid = current_sid();
	int err;

5039
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5040 5041 5042 5043 5044 5045 5046
			   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;
5047
	tunsec->sid = sid;
5048 5049 5050 5051

	return 0;
}

L
Linus Torvalds 已提交
5052 5053 5054 5055 5056
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
5057
	struct sk_security_struct *sksec = sk->sk_security;
5058

5059
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
5060 5061 5062
		err = -EINVAL;
		goto out;
	}
5063
	nlh = nlmsg_hdr(skb);
5064

5065
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
5066 5067
	if (err) {
		if (err == -EINVAL) {
5068 5069 5070
			pr_warn_ratelimited("SELinux: unrecognized netlink"
			       " message: protocol=%hu nlmsg_type=%hu sclass=%s"
			       " pig=%d comm=%s\n",
5071
			       sk->sk_protocol, nlh->nlmsg_type,
5072 5073
			       secclass_map[sksec->sclass - 1].name,
			       task_pid_nr(current), current->comm);
5074
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
5075 5076 5077 5078 5079 5080 5081 5082 5083
				err = 0;
		}

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

5084
	err = sock_has_perm(sk, perm);
L
Linus Torvalds 已提交
5085 5086 5087 5088 5089 5090
out:
	return err;
}

#ifdef CONFIG_NETFILTER

5091 5092
static unsigned int selinux_ip_forward(struct sk_buff *skb,
				       const struct net_device *indev,
5093
				       u16 family)
L
Linus Torvalds 已提交
5094
{
5095
	int err;
5096 5097
	char *addrp;
	u32 peer_sid;
5098
	struct common_audit_data ad;
5099
	struct lsm_network_audit net = {0,};
5100
	u8 secmark_active;
5101
	u8 netlbl_active;
5102
	u8 peerlbl_active;
5103

5104 5105
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
5106

5107
	secmark_active = selinux_secmark_enabled();
5108
	netlbl_active = netlbl_enabled();
5109
	peerlbl_active = selinux_peerlbl_enabled();
5110 5111
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
5112

5113 5114 5115
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

5116
	ad.type = LSM_AUDIT_DATA_NET;
5117
	ad.u.net = &net;
5118
	ad.u.net->netif = indev->ifindex;
5119
	ad.u.net->family = family;
5120 5121 5122
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

5123
	if (peerlbl_active) {
5124 5125
		err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
					       addrp, family, peer_sid, &ad);
5126
		if (err) {
5127
			selinux_netlbl_err(skb, family, err, 1);
5128
			return NF_DROP;
5129 5130
		}
	}
5131 5132 5133 5134 5135 5136

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

5137 5138 5139 5140 5141 5142 5143 5144
	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;

5145 5146 5147
	return NF_ACCEPT;
}

5148
static unsigned int selinux_ipv4_forward(void *priv,
5149
					 struct sk_buff *skb,
5150
					 const struct nf_hook_state *state)
5151
{
5152
	return selinux_ip_forward(skb, state->in, PF_INET);
5153 5154
}

5155
#if IS_ENABLED(CONFIG_IPV6)
5156
static unsigned int selinux_ipv6_forward(void *priv,
5157
					 struct sk_buff *skb,
5158
					 const struct nf_hook_state *state)
5159
{
5160
	return selinux_ip_forward(skb, state->in, PF_INET6);
5161 5162 5163
}
#endif	/* IPV6 */

5164 5165 5166
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
5167
	struct sock *sk;
5168 5169 5170 5171 5172 5173 5174 5175
	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 */
5176 5177 5178 5179
	sk = skb->sk;
	if (sk) {
		struct sk_security_struct *sksec;

5180
		if (sk_listener(sk))
5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196
			/* 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;
5197 5198 5199 5200 5201 5202 5203 5204 5205
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

5206
static unsigned int selinux_ipv4_output(void *priv,
5207
					struct sk_buff *skb,
5208
					const struct nf_hook_state *state)
5209 5210 5211 5212
{
	return selinux_ip_output(skb, PF_INET);
}

5213
#if IS_ENABLED(CONFIG_IPV6)
5214 5215 5216 5217 5218 5219 5220 5221
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 */

5222 5223
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
5224
						u16 family)
5225
{
5226
	struct sock *sk = skb_to_full_sk(skb);
5227
	struct sk_security_struct *sksec;
5228
	struct common_audit_data ad;
5229
	struct lsm_network_audit net = {0,};
5230 5231
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
5232

5233 5234 5235 5236
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

5237
	ad.type = LSM_AUDIT_DATA_NET;
5238 5239 5240
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5241 5242 5243
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

5244
	if (selinux_secmark_enabled())
5245
		if (avc_has_perm(sksec->sid, skb->secmark,
5246
				 SECCLASS_PACKET, PACKET__SEND, &ad))
5247
			return NF_DROP_ERR(-ECONNREFUSED);
5248

5249 5250
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
5251 5252

	return NF_ACCEPT;
5253 5254
}

5255 5256
static unsigned int selinux_ip_postroute(struct sk_buff *skb,
					 const struct net_device *outdev,
5257
					 u16 family)
5258
{
5259 5260
	u32 secmark_perm;
	u32 peer_sid;
5261
	int ifindex = outdev->ifindex;
5262
	struct sock *sk;
5263
	struct common_audit_data ad;
5264
	struct lsm_network_audit net = {0,};
5265 5266 5267
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
5268

5269 5270 5271 5272
	/* 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. */
5273
	if (!selinux_policycap_netpeer)
5274
		return selinux_ip_postroute_compat(skb, ifindex, family);
5275 5276 5277 5278 5279 5280

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

5281
	sk = skb_to_full_sk(skb);
5282

5283
#ifdef CONFIG_XFRM
5284 5285 5286 5287 5288
	/* 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
5289 5290 5291 5292 5293 5294 5295
	 *       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 &&
5296
	    !(sk && sk_listener(sk)))
5297
		return NF_ACCEPT;
5298
#endif
5299

5300
	if (sk == NULL) {
5301 5302 5303 5304
		/* 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. */
5305 5306
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
5307
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5308
				return NF_DROP;
5309 5310
		} else {
			secmark_perm = PACKET__SEND;
5311
			peer_sid = SECINITSID_KERNEL;
5312
		}
5313
	} else if (sk_listener(sk)) {
5314 5315 5316 5317 5318 5319 5320 5321 5322 5323
		/* 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;
5324 5325 5326
		struct sk_security_struct *sksec;

		sksec = sk->sk_security;
5327 5328
		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
			return NF_DROP;
5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343
		/* 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;
5344
				break;
5345 5346 5347 5348
			default:
				return NF_DROP_ERR(-ECONNREFUSED);
			}
		}
5349 5350 5351
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
5352
	} else {
5353 5354
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
5355 5356 5357 5358
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
5359

5360
	ad.type = LSM_AUDIT_DATA_NET;
5361 5362 5363
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5364
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5365
		return NF_DROP;
5366

5367 5368 5369
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
5370
			return NF_DROP_ERR(-ECONNREFUSED);
5371 5372 5373 5374 5375

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

5376
		if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5377
			return NF_DROP;
5378 5379
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5380
			return NF_DROP_ERR(-ECONNREFUSED);
5381 5382

		if (sel_netnode_sid(addrp, family, &node_sid))
5383
			return NF_DROP;
5384 5385
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
5386
			return NF_DROP_ERR(-ECONNREFUSED);
5387
	}
5388

5389
	return NF_ACCEPT;
L
Linus Torvalds 已提交
5390 5391
}

5392
static unsigned int selinux_ipv4_postroute(void *priv,
5393
					   struct sk_buff *skb,
5394
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5395
{
5396
	return selinux_ip_postroute(skb, state->out, PF_INET);
L
Linus Torvalds 已提交
5397 5398
}

5399
#if IS_ENABLED(CONFIG_IPV6)
5400
static unsigned int selinux_ipv6_postroute(void *priv,
5401
					   struct sk_buff *skb,
5402
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5403
{
5404
	return selinux_ip_postroute(skb, state->out, PF_INET6);
L
Linus Torvalds 已提交
5405 5406 5407 5408 5409 5410 5411
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
{
5412
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
5413 5414
}

5415
static int ipc_alloc_security(struct kern_ipc_perm *perm,
L
Linus Torvalds 已提交
5416 5417 5418 5419
			      u16 sclass)
{
	struct ipc_security_struct *isec;

J
James Morris 已提交
5420
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5421 5422 5423 5424
	if (!isec)
		return -ENOMEM;

	isec->sclass = sclass;
5425
	isec->sid = current_sid();
L
Linus Torvalds 已提交
5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440 5441
	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
5442
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460
	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,
5461
			u32 perms)
L
Linus Torvalds 已提交
5462 5463
{
	struct ipc_security_struct *isec;
5464
	struct common_audit_data ad;
5465
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5466 5467 5468

	isec = ipc_perms->security;

5469
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5470 5471
	ad.u.ipc_id = ipc_perms->key;

5472
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5473 5474 5475 5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488
}

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;
5489
	struct common_audit_data ad;
5490
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5491 5492
	int rc;

5493
	rc = ipc_alloc_security(&msq->q_perm, SECCLASS_MSGQ);
L
Linus Torvalds 已提交
5494 5495 5496 5497 5498
	if (rc)
		return rc;

	isec = msq->q_perm.security;

5499
	ad.type = LSM_AUDIT_DATA_IPC;
5500
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5501

5502
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518
			  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;
5519
	struct common_audit_data ad;
5520
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5521 5522 5523

	isec = msq->q_perm.security;

5524
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5525 5526
	ad.u.ipc_id = msq->q_perm.key;

5527
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5528 5529 5530 5531 5532 5533 5534 5535
			    MSGQ__ASSOCIATE, &ad);
}

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

5536
	switch (cmd) {
L
Linus Torvalds 已提交
5537 5538 5539
	case IPC_INFO:
	case MSG_INFO:
		/* No specific object, just general system-wide information. */
5540 5541
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555
	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;
	}

5556
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5557 5558 5559 5560 5561 5562 5563
	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;
5564
	struct common_audit_data ad;
5565
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5566 5567 5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578
	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
		 */
5579
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5580
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5581 5582 5583 5584
		if (rc)
			return rc;
	}

5585
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5586 5587 5588
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5589
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5590 5591 5592
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5593 5594
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5595 5596
	if (!rc)
		/* Can the message be put in the queue? */
5597 5598
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5599 5600 5601 5602 5603 5604 5605 5606 5607 5608

	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;
5609
	struct common_audit_data ad;
5610
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5611 5612 5613 5614 5615
	int rc;

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

5616
	ad.type = LSM_AUDIT_DATA_IPC;
5617
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5618

5619
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5620 5621
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5622
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5623 5624 5625 5626 5627 5628 5629 5630
				  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;
5631
	struct common_audit_data ad;
5632
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5633 5634
	int rc;

5635
	rc = ipc_alloc_security(&shp->shm_perm, SECCLASS_SHM);
L
Linus Torvalds 已提交
5636 5637 5638 5639 5640
	if (rc)
		return rc;

	isec = shp->shm_perm.security;

5641
	ad.type = LSM_AUDIT_DATA_IPC;
5642
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5643

5644
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658 5659 5660
			  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;
5661
	struct common_audit_data ad;
5662
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5663 5664 5665

	isec = shp->shm_perm.security;

5666
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5667 5668
	ad.u.ipc_id = shp->shm_perm.key;

5669
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5670 5671 5672 5673 5674 5675 5676 5677 5678
			    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;

5679
	switch (cmd) {
L
Linus Torvalds 已提交
5680 5681 5682
	case IPC_INFO:
	case SHM_INFO:
		/* No specific object, just general system-wide information. */
5683 5684
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699 5700 5701 5702
	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;
	}

5703
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5704 5705 5706 5707 5708 5709 5710 5711 5712 5713 5714 5715 5716
	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;

5717
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5718 5719 5720 5721 5722 5723
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5724
	struct common_audit_data ad;
5725
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5726 5727
	int rc;

5728
	rc = ipc_alloc_security(&sma->sem_perm, SECCLASS_SEM);
L
Linus Torvalds 已提交
5729 5730 5731 5732 5733
	if (rc)
		return rc;

	isec = sma->sem_perm.security;

5734
	ad.type = LSM_AUDIT_DATA_IPC;
5735
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5736

5737
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750 5751 5752 5753
			  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;
5754
	struct common_audit_data ad;
5755
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5756 5757 5758

	isec = sma->sem_perm.security;

5759
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5760 5761
	ad.u.ipc_id = sma->sem_perm.key;

5762
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5763 5764 5765 5766 5767 5768 5769 5770 5771
			    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;

5772
	switch (cmd) {
L
Linus Torvalds 已提交
5773 5774 5775
	case IPC_INFO:
	case SEM_INFO:
		/* No specific object, just general system-wide information. */
5776 5777
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5778 5779 5780 5781 5782 5783 5784 5785 5786 5787 5788 5789 5790 5791 5792 5793 5794 5795 5796 5797 5798 5799 5800 5801 5802 5803 5804
	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;
	}

5805
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818
	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;

5819
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834
}

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;

5835
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5836 5837
}

5838 5839 5840 5841 5842 5843
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5844
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5845 5846 5847 5848 5849 5850
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5851
			       char *name, char **value)
L
Linus Torvalds 已提交
5852
{
5853
	const struct task_security_struct *__tsec;
5854
	u32 sid;
L
Linus Torvalds 已提交
5855
	int error;
5856
	unsigned len;
L
Linus Torvalds 已提交
5857

5858 5859 5860
	rcu_read_lock();
	__tsec = __task_cred(p)->security;

L
Linus Torvalds 已提交
5861
	if (current != p) {
5862 5863
		error = avc_has_perm(current_sid(), __tsec->sid,
				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
L
Linus Torvalds 已提交
5864
		if (error)
5865
			goto bad;
L
Linus Torvalds 已提交
5866 5867 5868
	}

	if (!strcmp(name, "current"))
5869
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5870
	else if (!strcmp(name, "prev"))
5871
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5872
	else if (!strcmp(name, "exec"))
5873
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5874
	else if (!strcmp(name, "fscreate"))
5875
		sid = __tsec->create_sid;
5876
	else if (!strcmp(name, "keycreate"))
5877
		sid = __tsec->keycreate_sid;
5878
	else if (!strcmp(name, "sockcreate"))
5879
		sid = __tsec->sockcreate_sid;
5880 5881 5882 5883
	else {
		error = -EINVAL;
		goto bad;
	}
5884
	rcu_read_unlock();
L
Linus Torvalds 已提交
5885 5886 5887 5888

	if (!sid)
		return 0;

5889 5890 5891 5892
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5893

5894
bad:
5895
	rcu_read_unlock();
5896
	return error;
L
Linus Torvalds 已提交
5897 5898
}

5899
static int selinux_setprocattr(const char *name, void *value, size_t size)
L
Linus Torvalds 已提交
5900 5901
{
	struct task_security_struct *tsec;
D
David Howells 已提交
5902
	struct cred *new;
5903
	u32 mysid = current_sid(), sid = 0, ptsid;
L
Linus Torvalds 已提交
5904 5905 5906 5907 5908 5909 5910
	int error;
	char *str = value;

	/*
	 * Basic control over ability to set these attributes at all.
	 */
	if (!strcmp(name, "exec"))
5911 5912
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETEXEC, NULL);
L
Linus Torvalds 已提交
5913
	else if (!strcmp(name, "fscreate"))
5914 5915
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETFSCREATE, NULL);
5916
	else if (!strcmp(name, "keycreate"))
5917 5918
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETKEYCREATE, NULL);
5919
	else if (!strcmp(name, "sockcreate"))
5920 5921
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETSOCKCREATE, NULL);
L
Linus Torvalds 已提交
5922
	else if (!strcmp(name, "current"))
5923 5924
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETCURRENT, NULL);
L
Linus Torvalds 已提交
5925 5926 5927 5928 5929 5930
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
5931
	if (size && str[0] && str[0] != '\n') {
L
Linus Torvalds 已提交
5932 5933 5934 5935
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
5936
		error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5937
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5938
			if (!has_cap_mac_admin(true)) {
5939 5940 5941 5942 5943 5944 5945 5946 5947 5948 5949 5950 5951 5952
				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);

5953
				return error;
5954
			}
5955 5956 5957
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5958 5959 5960 5961
		if (error)
			return error;
	}

D
David Howells 已提交
5962 5963 5964 5965
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5966 5967 5968
	/* 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
5969
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5970 5971
	   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
5972 5973
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5974
		tsec->exec_sid = sid;
D
David Howells 已提交
5975
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5976
		tsec->create_sid = sid;
D
David Howells 已提交
5977
	} else if (!strcmp(name, "keycreate")) {
5978 5979
		error = avc_has_perm(mysid, sid, SECCLASS_KEY, KEY__CREATE,
				     NULL);
5980
		if (error)
D
David Howells 已提交
5981
			goto abort_change;
5982
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5983
	} else if (!strcmp(name, "sockcreate")) {
5984
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5985 5986
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5987
		if (sid == 0)
D
David Howells 已提交
5988 5989 5990 5991
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5992
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5993 5994 5995
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5996
		}
L
Linus Torvalds 已提交
5997 5998 5999

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6000
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
6001
		if (error)
D
David Howells 已提交
6002
			goto abort_change;
L
Linus Torvalds 已提交
6003 6004 6005

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
6006
		ptsid = ptrace_parent_sid();
6007
		if (ptsid != 0) {
D
David Howells 已提交
6008 6009
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
6010
			if (error)
D
David Howells 已提交
6011
				goto abort_change;
L
Linus Torvalds 已提交
6012 6013
		}

D
David Howells 已提交
6014 6015 6016 6017 6018 6019 6020
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
6021
	return size;
D
David Howells 已提交
6022 6023 6024 6025

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
6026 6027
}

6028 6029 6030 6031 6032
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

6033 6034 6035 6036 6037
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

6038
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6039
{
6040
	return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
6041 6042
}

6043 6044
static void selinux_release_secctx(char *secdata, u32 seclen)
{
6045
	kfree(secdata);
6046 6047
}

6048 6049 6050 6051
static void selinux_inode_invalidate_secctx(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;

6052
	spin_lock(&isec->lock);
6053
	isec->initialized = LABEL_INVALID;
6054
	spin_unlock(&isec->lock);
6055 6056
}

6057 6058 6059 6060 6061 6062 6063 6064 6065 6066 6067 6068 6069 6070 6071 6072 6073 6074 6075 6076 6077 6078 6079 6080 6081 6082
/*
 *	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;
}
6083 6084
#ifdef CONFIG_KEYS

D
David Howells 已提交
6085
static int selinux_key_alloc(struct key *k, const struct cred *cred,
6086
			     unsigned long flags)
6087
{
D
David Howells 已提交
6088
	const struct task_security_struct *tsec;
6089 6090 6091 6092 6093 6094
	struct key_security_struct *ksec;

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

D
David Howells 已提交
6095 6096 6097
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
6098
	else
D
David Howells 已提交
6099
		ksec->sid = tsec->sid;
6100

6101
	k->security = ksec;
6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113
	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
6114
				  const struct cred *cred,
6115
				  unsigned perm)
6116 6117 6118
{
	struct key *key;
	struct key_security_struct *ksec;
6119
	u32 sid;
6120 6121 6122 6123 6124 6125 6126

	/* 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
6127
	sid = cred_sid(cred);
6128 6129 6130 6131 6132

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6133 6134
}

6135 6136 6137 6138 6139 6140 6141 6142 6143 6144 6145 6146 6147
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;
}
6148 6149 6150 6151 6152 6153 6154 6155 6156 6157 6158 6159 6160 6161 6162
#endif

#ifdef CONFIG_SECURITY_INFINIBAND
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;
}
6163

6164 6165 6166 6167
static void selinux_ib_free_security(void *ib_sec)
{
	kfree(ib_sec);
}
6168 6169
#endif

6170
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6171 6172 6173 6174 6175 6176 6177 6178 6179 6180 6181 6182 6183 6184 6185 6186 6187 6188 6189 6190 6191 6192 6193 6194 6195 6196 6197 6198 6199 6200 6201 6202 6203 6204 6205 6206
	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),
6207
	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6208 6209 6210 6211 6212 6213 6214 6215 6216 6217 6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228 6229 6230 6231 6232 6233

	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),
6234
	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6235
	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246 6247 6248 6249 6250 6251

	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),

6252
	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6253 6254 6255 6256 6257 6258 6259
	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),
6260
	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6261 6262 6263 6264 6265 6266 6267
	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),
6268
	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6269 6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284 6285 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
	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),
6311
	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6312 6313 6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326 6327 6328 6329 6330 6331 6332 6333 6334 6335 6336 6337 6338 6339 6340 6341 6342 6343 6344 6345 6346 6347 6348 6349 6350 6351 6352 6353
	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),
6354 6355 6356 6357
#ifdef CONFIG_SECURITY_INFINIBAND
	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
#endif
6358
#ifdef CONFIG_SECURITY_NETWORK_XFRM
6359 6360 6361 6362 6363 6364 6365 6366 6367 6368 6369 6370 6371
	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
6372
#endif
6373 6374

#ifdef CONFIG_KEYS
6375 6376 6377 6378
	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),
6379
#endif
6380 6381

#ifdef CONFIG_AUDIT
6382 6383 6384 6385
	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),
6386
#endif
L
Linus Torvalds 已提交
6387 6388 6389 6390
};

static __init int selinux_init(void)
{
C
Casey Schaufler 已提交
6391
	if (!security_module_enable("selinux")) {
6392 6393 6394 6395
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
6396 6397 6398 6399 6400 6401 6402 6403
	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
6404
	cred_init_security();
L
Linus Torvalds 已提交
6405

6406 6407
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

6408 6409
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
6410
					    0, SLAB_PANIC, NULL);
6411 6412 6413
	file_security_cache = kmem_cache_create("selinux_file_security",
					    sizeof(struct file_security_struct),
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
6414 6415
	avc_init();

6416
	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
L
Linus Torvalds 已提交
6417

6418 6419 6420
	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC netcache callback\n");

6421 6422 6423
	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC LSM notifier callback\n");

6424
	if (selinux_enforcing)
6425
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
6426
	else
6427
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6428

L
Linus Torvalds 已提交
6429 6430 6431
	return 0;
}

6432 6433 6434 6435 6436
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
6437 6438
void selinux_complete_init(void)
{
6439
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
6440 6441

	/* Set up any superblocks initialized prior to the policy load. */
6442
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6443
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
6444 6445 6446 6447 6448 6449
}

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

6450
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
6451

6452
static struct nf_hook_ops selinux_nf_ops[] = {
6453 6454
	{
		.hook =		selinux_ipv4_postroute,
6455
		.pf =		NFPROTO_IPV4,
6456 6457 6458 6459 6460
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
6461
		.pf =		NFPROTO_IPV4,
6462 6463
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6464 6465 6466
	},
	{
		.hook =		selinux_ipv4_output,
6467
		.pf =		NFPROTO_IPV4,
6468 6469
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6470
	},
6471
#if IS_ENABLED(CONFIG_IPV6)
6472 6473
	{
		.hook =		selinux_ipv6_postroute,
6474
		.pf =		NFPROTO_IPV6,
6475 6476 6477 6478 6479
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
6480
		.pf =		NFPROTO_IPV6,
6481 6482
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
6483
	},
6484 6485 6486 6487 6488 6489
	{
		.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
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#endif	/* IPV6 */
6491
};
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static int __init selinux_nf_ip_init(void)
{
6495
	int err;
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Linus Torvalds 已提交
6496 6497

	if (!selinux_enabled)
6498
		return 0;
6499 6500 6501

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

6502
	err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6503
	if (err)
6504
		panic("SELinux: nf_register_hooks: error %d\n", err);
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Linus Torvalds 已提交
6505

6506
	return 0;
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}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6514
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
6515

6516
	nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
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6517 6518 6519
}
#endif

6520
#else /* CONFIG_NETFILTER */
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6521 6522 6523 6524 6525

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6526
#endif /* CONFIG_NETFILTER */
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Linus Torvalds 已提交
6527 6528

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6529 6530
static int selinux_disabled;

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Linus Torvalds 已提交
6531 6532 6533 6534 6535 6536 6537 6538 6539 6540 6541 6542 6543 6544 6545
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;
6546
	selinux_enabled = 0;
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Linus Torvalds 已提交
6547

C
Casey Schaufler 已提交
6548
	security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
L
Linus Torvalds 已提交
6549

6550 6551 6552
	/* Try to destroy the avc node cache */
	avc_disable();

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6553 6554 6555 6556 6557 6558 6559 6560 6561
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif