[thirdparty/linux.git] / security / inode.c

/*
 *  inode.c - securityfs
 *
 *  Copyright (C) 2005 Greg Kroah-Hartman <gregkh@suse.de>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License version
 *	2 as published by the Free Software Foundation.
 *
 *  Based on fs/debugfs/inode.c which had the following copyright notice:
 *    Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
 *    Copyright (C) 2004 IBM Inc.
 */

/* #define DEBUG */
#include <linux/sysfs.h>
#include <linux/kobject.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/pagemap.h>
#include <linux/init.h>
#include <linux/namei.h>
#include <linux/security.h>
#include <linux/lsm_hooks.h>
#include <linux/magic.h>

static struct vfsmount *mount;
static int mount_count;

static void securityfs_evict_inode(struct inode *inode)
{
	truncate_inode_pages_final(&inode->i_data);
	clear_inode(inode);
	if (S_ISLNK(inode->i_mode))
		kfree(inode->i_link);
}

static const struct super_operations securityfs_super_operations = {
	.statfs		= simple_statfs,
	.evict_inode	= securityfs_evict_inode,
};

static int fill_super(struct super_block *sb, void *data, int silent)
{
	static const struct tree_descr files[] = {{""}};
	int error;

	error = simple_fill_super(sb, SECURITYFS_MAGIC, files);
	if (error)
		return error;

	sb->s_op = &securityfs_super_operations;

	return 0;
}

static struct dentry *get_sb(struct file_system_type *fs_type,
		  int flags, const char *dev_name,
		  void *data)
{
	return mount_single(fs_type, flags, data, fill_super);
}

static struct file_system_type fs_type = {
	.owner =	THIS_MODULE,
	.name =		"securityfs",
	.mount =	get_sb,
	.kill_sb =	kill_litter_super,
};

/**
 * securityfs_create_dentry - create a dentry in the securityfs filesystem
 *
 * @name: a pointer to a string containing the name of the file to create.
 * @mode: the permission that the file should have
 * @parent: a pointer to the parent dentry for this file.  This should be a
 *          directory dentry if set.  If this parameter is %NULL, then the
 *          file will be created in the root of the securityfs filesystem.
 * @data: a pointer to something that the caller will want to get to later
 *        on.  The inode.i_private pointer will point to this value on
 *        the open() call.
 * @fops: a pointer to a struct file_operations that should be used for
 *        this file.
 * @iops: a point to a struct of inode_operations that should be used for
 *        this file/dir
 *
 * This is the basic "create a file/dir/symlink" function for
 * securityfs.  It allows for a wide range of flexibility in creating
 * a file, or a directory (if you want to create a directory, the
 * securityfs_create_dir() function is recommended to be used
 * instead).
 *
 * This function returns a pointer to a dentry if it succeeds.  This
 * pointer must be passed to the securityfs_remove() function when the
 * file is to be removed (no automatic cleanup happens if your module
 * is unloaded, you are responsible here).  If an error occurs, the
 * function will return the error value (via ERR_PTR).
 *
 * If securityfs is not enabled in the kernel, the value %-ENODEV is
 * returned.
 */
static struct dentry *securityfs_create_dentry(const char *name, umode_t mode,
					struct dentry *parent, void *data,
					const struct file_operations *fops,
					const struct inode_operations *iops)
{
	struct dentry *dentry;
	struct inode *dir, *inode;
	int error;

	if (!(mode & S_IFMT))
		mode = (mode & S_IALLUGO) | S_IFREG;

	pr_debug("securityfs: creating file '%s'\n",name);

	error = simple_pin_fs(&fs_type, &mount, &mount_count);
	if (error)
		return ERR_PTR(error);

	if (!parent)
		parent = mount->mnt_root;

	dir = d_inode(parent);

	inode_lock(dir);
	dentry = lookup_one_len(name, parent, strlen(name));
	if (IS_ERR(dentry))
		goto out;

	if (d_really_is_positive(dentry)) {
		error = -EEXIST;
		goto out1;
	}

	inode = new_inode(dir->i_sb);
	if (!inode) {
		error = -ENOMEM;
		goto out1;
	}

	inode->i_ino = get_next_ino();
	inode->i_mode = mode;
	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
	inode->i_private = data;
	if (S_ISDIR(mode)) {
		inode->i_op = &simple_dir_inode_operations;
		inode->i_fop = &simple_dir_operations;
		inc_nlink(inode);
		inc_nlink(dir);
	} else if (S_ISLNK(mode)) {
		inode->i_op = iops ? iops : &simple_symlink_inode_operations;
		inode->i_link = data;
	} else {
		inode->i_fop = fops;
	}
	d_instantiate(dentry, inode);
	dget(dentry);
	inode_unlock(dir);
	return dentry;

out1:
	dput(dentry);
	dentry = ERR_PTR(error);
out:
	inode_unlock(dir);
	simple_release_fs(&mount, &mount_count);
	return dentry;
}

/**
 * securityfs_create_file - create a file in the securityfs filesystem
 *
 * @name: a pointer to a string containing the name of the file to create.
 * @mode: the permission that the file should have
 * @parent: a pointer to the parent dentry for this file.  This should be a
 *          directory dentry if set.  If this parameter is %NULL, then the
 *          file will be created in the root of the securityfs filesystem.
 * @data: a pointer to something that the caller will want to get to later
 *        on.  The inode.i_private pointer will point to this value on
 *        the open() call.
 * @fops: a pointer to a struct file_operations that should be used for
 *        this file.
 *
 * This function creates a file in securityfs with the given @name.
 *
 * This function returns a pointer to a dentry if it succeeds.  This
 * pointer must be passed to the securityfs_remove() function when the file is
 * to be removed (no automatic cleanup happens if your module is unloaded,
 * you are responsible here).  If an error occurs, the function will return
 * the error value (via ERR_PTR).
 *
 * If securityfs is not enabled in the kernel, the value %-ENODEV is
 * returned.
 */
struct dentry *securityfs_create_file(const char *name, umode_t mode,
				      struct dentry *parent, void *data,
				      const struct file_operations *fops)
{
	return securityfs_create_dentry(name, mode, parent, data, fops, NULL);
}
EXPORT_SYMBOL_GPL(securityfs_create_file);

/**
 * securityfs_create_dir - create a directory in the securityfs filesystem
 *
 * @name: a pointer to a string containing the name of the directory to
 *        create.
 * @parent: a pointer to the parent dentry for this file.  This should be a
 *          directory dentry if set.  If this parameter is %NULL, then the
 *          directory will be created in the root of the securityfs filesystem.
 *
 * This function creates a directory in securityfs with the given @name.
 *
 * This function returns a pointer to a dentry if it succeeds.  This
 * pointer must be passed to the securityfs_remove() function when the file is
 * to be removed (no automatic cleanup happens if your module is unloaded,
 * you are responsible here).  If an error occurs, the function will return
 * the error value (via ERR_PTR).
 *
 * If securityfs is not enabled in the kernel, the value %-ENODEV is
 * returned.
 */
struct dentry *securityfs_create_dir(const char *name, struct dentry *parent)
{
	return securityfs_create_file(name, S_IFDIR | 0755, parent, NULL, NULL);
}
EXPORT_SYMBOL_GPL(securityfs_create_dir);

/**
 * securityfs_create_symlink - create a symlink in the securityfs filesystem
 *
 * @name: a pointer to a string containing the name of the symlink to
 *        create.
 * @parent: a pointer to the parent dentry for the symlink.  This should be a
 *          directory dentry if set.  If this parameter is %NULL, then the
 *          directory will be created in the root of the securityfs filesystem.
 * @target: a pointer to a string containing the name of the symlink's target.
 *          If this parameter is %NULL, then the @iops parameter needs to be
 *          setup to handle .readlink and .get_link inode_operations.
 * @iops: a pointer to the struct inode_operations to use for the symlink. If
 *        this parameter is %NULL, then the default simple_symlink_inode
 *        operations will be used.
 *
 * This function creates a symlink in securityfs with the given @name.
 *
 * This function returns a pointer to a dentry if it succeeds.  This
 * pointer must be passed to the securityfs_remove() function when the file is
 * to be removed (no automatic cleanup happens if your module is unloaded,
 * you are responsible here).  If an error occurs, the function will return
 * the error value (via ERR_PTR).
 *
 * If securityfs is not enabled in the kernel, the value %-ENODEV is
 * returned.
 */
struct dentry *securityfs_create_symlink(const char *name,
					 struct dentry *parent,
					 const char *target,
					 const struct inode_operations *iops)
{
	struct dentry *dent;
	char *link = NULL;

	if (target) {
		link = kstrdup(target, GFP_KERNEL);
		if (!link)
			return ERR_PTR(-ENOMEM);
	}
	dent = securityfs_create_dentry(name, S_IFLNK | 0444, parent,
					link, NULL, iops);
	if (IS_ERR(dent))
		kfree(link);

	return dent;
}
EXPORT_SYMBOL_GPL(securityfs_create_symlink);

/**
 * securityfs_remove - removes a file or directory from the securityfs filesystem
 *
 * @dentry: a pointer to a the dentry of the file or directory to be removed.
 *
 * This function removes a file or directory in securityfs that was previously
 * created with a call to another securityfs function (like
 * securityfs_create_file() or variants thereof.)
 *
 * This function is required to be called in order for the file to be
 * removed. No automatic cleanup of files will happen when a module is
 * removed; you are responsible here.
 */
void securityfs_remove(struct dentry *dentry)
{
	struct inode *dir;

	if (!dentry || IS_ERR(dentry))
		return;

	dir = d_inode(dentry->d_parent);
	inode_lock(dir);
	if (simple_positive(dentry)) {
		if (d_is_dir(dentry))
			simple_rmdir(dir, dentry);
		else
			simple_unlink(dir, dentry);
		dput(dentry);
	}
	inode_unlock(dir);
	simple_release_fs(&mount, &mount_count);
}
EXPORT_SYMBOL_GPL(securityfs_remove);

#ifdef CONFIG_SECURITY
static struct dentry *lsm_dentry;
static ssize_t lsm_read(struct file *filp, char __user *buf, size_t count,
			loff_t *ppos)
{
	return simple_read_from_buffer(buf, count, ppos, lsm_names,
		strlen(lsm_names));
}

static const struct file_operations lsm_ops = {
	.read = lsm_read,
	.llseek = generic_file_llseek,
};
#endif

static int __init securityfs_init(void)
{
	int retval;

	retval = sysfs_create_mount_point(kernel_kobj, "security");
	if (retval)
		return retval;

	retval = register_filesystem(&fs_type);
	if (retval) {
		sysfs_remove_mount_point(kernel_kobj, "security");
		return retval;
	}
#ifdef CONFIG_SECURITY
	lsm_dentry = securityfs_create_file("lsm", 0444, NULL, NULL,
						&lsm_ops);
#endif
	return 0;
}
core_initcall(securityfs_init);
Commit	Line	Data
b67dbf9d GKH	1	/*
	2	* inode.c - securityfs
	3	*
	4	* Copyright (C) 2005 Greg Kroah-Hartman <gregkh@suse.de>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License version
	8	* 2 as published by the Free Software Foundation.
	9	*
	10	* Based on fs/debugfs/inode.c which had the following copyright notice:
	11	* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
	12	* Copyright (C) 2004 IBM Inc.
	13	*/
	14
	15	/* #define DEBUG */
1072bd67 PG	16	#include <linux/sysfs.h>
1072bd67 PG	17	#include <linux/kobject.h>
b67dbf9d GKH	18	#include <linux/fs.h>
	19	#include <linux/mount.h>
	20	#include <linux/pagemap.h>
	21	#include <linux/init.h>
	22	#include <linux/namei.h>
	23	#include <linux/security.h>
d69dece5	24	#include <linux/lsm_hooks.h>
92562927	25	#include <linux/magic.h>
b67dbf9d GKH	26
	27	static struct vfsmount *mount;
	28	static int mount_count;
	29
6623ec7c JJ	30	static void securityfs_evict_inode(struct inode *inode)
	31	{
	32	truncate_inode_pages_final(&inode->i_data);
	33	clear_inode(inode);
	34	if (S_ISLNK(inode->i_mode))
	35	kfree(inode->i_link);
	36	}
	37
	38	static const struct super_operations securityfs_super_operations = {
	39	.statfs = simple_statfs,
	40	.evict_inode = securityfs_evict_inode,
	41	};
	42
b67dbf9d GKH	43	static int fill_super(struct super_block sb, void data, int silent)
b67dbf9d GKH	44	{
cda37124	45	static const struct tree_descr files[] = {{""}};
6623ec7c JJ	46	int error;
	47
	48	error = simple_fill_super(sb, SECURITYFS_MAGIC, files);
	49	if (error)
	50	return error;
	51
	52	sb->s_op = &securityfs_super_operations;
b67dbf9d	53
6623ec7c	54	return 0;
b67dbf9d GKH	55	}
b67dbf9d GKH	56
fc14f2fe	57	static struct dentry get_sb(struct file_system_type fs_type,
454e2398	58	int flags, const char *dev_name,
fc14f2fe	59	void *data)
b67dbf9d	60	{
fc14f2fe	61	return mount_single(fs_type, flags, data, fill_super);
b67dbf9d GKH	62	}
	63
	64	static struct file_system_type fs_type = {
	65	.owner = THIS_MODULE,
	66	.name = "securityfs",
fc14f2fe	67	.mount = get_sb,
b67dbf9d GKH	68	.kill_sb = kill_litter_super,
	69	};
	70
b67dbf9d	71	/**
6623ec7c	72	* securityfs_create_dentry - create a dentry in the securityfs filesystem
b67dbf9d GKH	73	*
	74	* @name: a pointer to a string containing the name of the file to create.
	75	* @mode: the permission that the file should have
	76	* @parent: a pointer to the parent dentry for this file. This should be a
3f23d815	77	* directory dentry if set. If this parameter is %NULL, then the
b67dbf9d GKH	78	* file will be created in the root of the securityfs filesystem.
b67dbf9d GKH	79	* @data: a pointer to something that the caller will want to get to later
8e18e294	80	* on. The inode.i_private pointer will point to this value on
b67dbf9d GKH	81	* the open() call.
	82	* @fops: a pointer to a struct file_operations that should be used for
	83	* this file.
6623ec7c JJ	84	* @iops: a point to a struct of inode_operations that should be used for
6623ec7c JJ	85	* this file/dir
b67dbf9d	86	*
6623ec7c JJ	87	* This is the basic "create a file/dir/symlink" function for
	88	* securityfs. It allows for a wide range of flexibility in creating
	89	* a file, or a directory (if you want to create a directory, the
	90	* securityfs_create_dir() function is recommended to be used
	91	* instead).
b67dbf9d	92	*
3f23d815	93	* This function returns a pointer to a dentry if it succeeds. This
6623ec7c JJ	94	* pointer must be passed to the securityfs_remove() function when the
	95	* file is to be removed (no automatic cleanup happens if your module
	96	* is unloaded, you are responsible here). If an error occurs, the
	97	* function will return the error value (via ERR_PTR).
b67dbf9d	98	*
3f23d815	99	* If securityfs is not enabled in the kernel, the value %-ENODEV is
faa3aad7	100	* returned.
b67dbf9d	101	*/
6623ec7c JJ	102	static struct dentry securityfs_create_dentry(const char name, umode_t mode,
	103	struct dentry parent, void data,
	104	const struct file_operations *fops,
	105	const struct inode_operations *iops)
b67dbf9d	106	{
3e25eb9c	107	struct dentry *dentry;
3e25eb9c	108	struct inode dir, inode;
b67dbf9d GKH	109	int error;
b67dbf9d GKH	110
6623ec7c	111	if (!(mode & S_IFMT))
3e25eb9c	112	mode = (mode & S_IALLUGO) \| S_IFREG;
3e25eb9c	113
b67dbf9d GKH	114	pr_debug("securityfs: creating file '%s'\n",name);
b67dbf9d GKH	115
1f5ce9e9	116	error = simple_pin_fs(&fs_type, &mount, &mount_count);
3e25eb9c AV	117	if (error)
	118	return ERR_PTR(error);
	119
	120	if (!parent)
	121	parent = mount->mnt_root;
	122
ce0b16dd	123	dir = d_inode(parent);
3e25eb9c	124
5955102c	125	inode_lock(dir);
3e25eb9c AV	126	dentry = lookup_one_len(name, parent, strlen(name));
	127	if (IS_ERR(dentry))
	128	goto out;
	129
ce0b16dd	130	if (d_really_is_positive(dentry)) {
3e25eb9c AV	131	error = -EEXIST;
3e25eb9c AV	132	goto out1;
b67dbf9d GKH	133	}
b67dbf9d GKH	134
3e25eb9c AV	135	inode = new_inode(dir->i_sb);
	136	if (!inode) {
	137	error = -ENOMEM;
	138	goto out1;
b67dbf9d GKH	139	}
b67dbf9d GKH	140
3e25eb9c AV	141	inode->i_ino = get_next_ino();
3e25eb9c AV	142	inode->i_mode = mode;
078cd827	143	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
3e25eb9c	144	inode->i_private = data;
6623ec7c	145	if (S_ISDIR(mode)) {
3e25eb9c AV	146	inode->i_op = &simple_dir_inode_operations;
	147	inode->i_fop = &simple_dir_operations;
	148	inc_nlink(inode);
	149	inc_nlink(dir);
6623ec7c JJ	150	} else if (S_ISLNK(mode)) {
	151	inode->i_op = iops ? iops : &simple_symlink_inode_operations;
	152	inode->i_link = data;
3e25eb9c AV	153	} else {
3e25eb9c AV	154	inode->i_fop = fops;
b67dbf9d	155	}
3e25eb9c AV	156	d_instantiate(dentry, inode);
3e25eb9c AV	157	dget(dentry);
5955102c	158	inode_unlock(dir);
3e25eb9c AV	159	return dentry;
	160
	161	out1:
	162	dput(dentry);
	163	dentry = ERR_PTR(error);
	164	out:
5955102c	165	inode_unlock(dir);
3e25eb9c	166	simple_release_fs(&mount, &mount_count);
b67dbf9d GKH	167	return dentry;
b67dbf9d GKH	168	}
6623ec7c JJ	169
	170	/**
	171	* securityfs_create_file - create a file in the securityfs filesystem
	172	*
	173	* @name: a pointer to a string containing the name of the file to create.
	174	* @mode: the permission that the file should have
	175	* @parent: a pointer to the parent dentry for this file. This should be a
	176	* directory dentry if set. If this parameter is %NULL, then the
	177	* file will be created in the root of the securityfs filesystem.
	178	* @data: a pointer to something that the caller will want to get to later
	179	* on. The inode.i_private pointer will point to this value on
	180	* the open() call.
	181	* @fops: a pointer to a struct file_operations that should be used for
	182	* this file.
	183	*
	184	* This function creates a file in securityfs with the given @name.
	185	*
	186	* This function returns a pointer to a dentry if it succeeds. This
	187	* pointer must be passed to the securityfs_remove() function when the file is
	188	* to be removed (no automatic cleanup happens if your module is unloaded,
	189	* you are responsible here). If an error occurs, the function will return
	190	* the error value (via ERR_PTR).
	191	*
	192	* If securityfs is not enabled in the kernel, the value %-ENODEV is
	193	* returned.
	194	*/
	195	struct dentry securityfs_create_file(const char name, umode_t mode,
	196	struct dentry parent, void data,
	197	const struct file_operations *fops)
	198	{
	199	return securityfs_create_dentry(name, mode, parent, data, fops, NULL);
	200	}
b67dbf9d GKH	201	EXPORT_SYMBOL_GPL(securityfs_create_file);
	202
	203	/**
	204	* securityfs_create_dir - create a directory in the securityfs filesystem
	205	*
	206	* @name: a pointer to a string containing the name of the directory to
	207	* create.
	208	* @parent: a pointer to the parent dentry for this file. This should be a
3f23d815	209	* directory dentry if set. If this parameter is %NULL, then the
b67dbf9d GKH	210	* directory will be created in the root of the securityfs filesystem.
b67dbf9d GKH	211	*
3f23d815	212	* This function creates a directory in securityfs with the given @name.
b67dbf9d	213	*
3f23d815	214	* This function returns a pointer to a dentry if it succeeds. This
b67dbf9d GKH	215	* pointer must be passed to the securityfs_remove() function when the file is
b67dbf9d GKH	216	* to be removed (no automatic cleanup happens if your module is unloaded,
1b460651 LG	217	* you are responsible here). If an error occurs, the function will return
1b460651 LG	218	* the error value (via ERR_PTR).
b67dbf9d	219	*
3f23d815	220	* If securityfs is not enabled in the kernel, the value %-ENODEV is
1b460651	221	* returned.
b67dbf9d GKH	222	*/
	223	struct dentry securityfs_create_dir(const char name, struct dentry *parent)
	224	{
6623ec7c	225	return securityfs_create_file(name, S_IFDIR \| 0755, parent, NULL, NULL);
b67dbf9d GKH	226	}
	227	EXPORT_SYMBOL_GPL(securityfs_create_dir);
	228
6623ec7c JJ	229	/**
	230	* securityfs_create_symlink - create a symlink in the securityfs filesystem
	231	*
	232	* @name: a pointer to a string containing the name of the symlink to
	233	* create.
	234	* @parent: a pointer to the parent dentry for the symlink. This should be a
	235	* directory dentry if set. If this parameter is %NULL, then the
	236	* directory will be created in the root of the securityfs filesystem.
	237	* @target: a pointer to a string containing the name of the symlink's target.
	238	* If this parameter is %NULL, then the @iops parameter needs to be
	239	* setup to handle .readlink and .get_link inode_operations.
	240	* @iops: a pointer to the struct inode_operations to use for the symlink. If
	241	* this parameter is %NULL, then the default simple_symlink_inode
	242	* operations will be used.
	243	*
	244	* This function creates a symlink in securityfs with the given @name.
	245	*
	246	* This function returns a pointer to a dentry if it succeeds. This
	247	* pointer must be passed to the securityfs_remove() function when the file is
	248	* to be removed (no automatic cleanup happens if your module is unloaded,
	249	* you are responsible here). If an error occurs, the function will return
	250	* the error value (via ERR_PTR).
	251	*
	252	* If securityfs is not enabled in the kernel, the value %-ENODEV is
	253	* returned.
	254	*/
	255	struct dentry securityfs_create_symlink(const char name,
	256	struct dentry *parent,
	257	const char *target,
	258	const struct inode_operations *iops)
	259	{
	260	struct dentry *dent;
	261	char *link = NULL;
	262
	263	if (target) {
	264	link = kstrdup(target, GFP_KERNEL);
	265	if (!link)
	266	return ERR_PTR(-ENOMEM);
	267	}
	268	dent = securityfs_create_dentry(name, S_IFLNK \| 0444, parent,
	269	link, NULL, iops);
	270	if (IS_ERR(dent))
	271	kfree(link);
	272
	273	return dent;
	274	}
	275	EXPORT_SYMBOL_GPL(securityfs_create_symlink);
	276
b67dbf9d GKH	277	/**
	278	* securityfs_remove - removes a file or directory from the securityfs filesystem
	279	*
3f23d815	280	* @dentry: a pointer to a the dentry of the file or directory to be removed.
b67dbf9d GKH	281	*
	282	* This function removes a file or directory in securityfs that was previously
	283	* created with a call to another securityfs function (like
	284	* securityfs_create_file() or variants thereof.)
	285	*
	286	* This function is required to be called in order for the file to be
3f23d815 RD	287	* removed. No automatic cleanup of files will happen when a module is
3f23d815 RD	288	* removed; you are responsible here.
b67dbf9d GKH	289	*/
	290	void securityfs_remove(struct dentry *dentry)
	291	{
4093d306	292	struct inode *dir;
b67dbf9d	293
d93e4c94	294	if (!dentry \|\| IS_ERR(dentry))
b67dbf9d GKH	295	return;
b67dbf9d GKH	296
4093d306 AV	297	dir = d_inode(dentry->d_parent);
4093d306 AV	298	inode_lock(dir);
dc3f4198 AV	299	if (simple_positive(dentry)) {
dc3f4198 AV	300	if (d_is_dir(dentry))
4093d306	301	simple_rmdir(dir, dentry);
dc3f4198	302	else
4093d306	303	simple_unlink(dir, dentry);
dc3f4198	304	dput(dentry);
b67dbf9d	305	}
4093d306	306	inode_unlock(dir);
b67dbf9d GKH	307	simple_release_fs(&mount, &mount_count);
	308	}
	309	EXPORT_SYMBOL_GPL(securityfs_remove);
	310
d69dece5 CS	311	#ifdef CONFIG_SECURITY
	312	static struct dentry *lsm_dentry;
	313	static ssize_t lsm_read(struct file filp, char __user buf, size_t count,
	314	loff_t *ppos)
	315	{
	316	return simple_read_from_buffer(buf, count, ppos, lsm_names,
	317	strlen(lsm_names));
	318	}
	319
	320	static const struct file_operations lsm_ops = {
	321	.read = lsm_read,
	322	.llseek = generic_file_llseek,
	323	};
	324	#endif
	325
b67dbf9d GKH	326	static int __init securityfs_init(void)
	327	{
	328	int retval;
	329
f9bb4882 EB	330	retval = sysfs_create_mount_point(kernel_kobj, "security");
	331	if (retval)
	332	return retval;
b67dbf9d GKH	333
b67dbf9d GKH	334	retval = register_filesystem(&fs_type);
d69dece5	335	if (retval) {
f9bb4882	336	sysfs_remove_mount_point(kernel_kobj, "security");
d69dece5 CS	337	return retval;
	338	}
	339	#ifdef CONFIG_SECURITY
	340	lsm_dentry = securityfs_create_file("lsm", 0444, NULL, NULL,
	341	&lsm_ops);
	342	#endif
	343	return 0;
b67dbf9d	344	}
b67dbf9d	345	core_initcall(securityfs_init);