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

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  inode.c - securityfs
 *
 *  Copyright (C) 2005 Greg Kroah-Hartman <gregkh@suse.de>
 *
 *  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/fs_context.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_free_inode(struct inode *inode)
{
	if (S_ISLNK(inode->i_mode))
		kfree(inode->i_link);
	free_inode_nonrcu(inode);
}

static const struct super_operations securityfs_super_operations = {
	.statfs		= simple_statfs,
	.free_inode	= securityfs_free_inode,
};

static int securityfs_fill_super(struct super_block *sb, struct fs_context *fc)
{
	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 int securityfs_get_tree(struct fs_context *fc)
{
	return get_tree_single(fc, securityfs_fill_super);
}

static const struct fs_context_operations securityfs_context_ops = {
	.get_tree	= securityfs_get_tree,
};

static int securityfs_init_fs_context(struct fs_context *fc)
{
	fc->ops = &securityfs_context_ops;
	return 0;
}

static struct file_system_type fs_type = {
	.owner =	THIS_MODULE,
	.name =		"securityfs",
	.init_fs_context = securityfs_init_fs_context,
	.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
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
b67dbf9d GKH	2	/*
	3	* inode.c - securityfs
	4	*
	5	* Copyright (C) 2005 Greg Kroah-Hartman <gregkh@suse.de>
	6	*
b67dbf9d GKH	7	* Based on fs/debugfs/inode.c which had the following copyright notice:
	8	* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
	9	* Copyright (C) 2004 IBM Inc.
	10	*/
	11
	12	/* #define DEBUG */
1072bd67 PG	13	#include <linux/sysfs.h>
1072bd67 PG	14	#include <linux/kobject.h>
b67dbf9d	15	#include <linux/fs.h>
5c86d7e0	16	#include <linux/fs_context.h>
b67dbf9d GKH	17	#include <linux/mount.h>
	18	#include <linux/pagemap.h>
	19	#include <linux/init.h>
	20	#include <linux/namei.h>
	21	#include <linux/security.h>
d69dece5	22	#include <linux/lsm_hooks.h>
92562927	23	#include <linux/magic.h>
b67dbf9d GKH	24
	25	static struct vfsmount *mount;
	26	static int mount_count;
	27
f614ee1e	28	static void securityfs_free_inode(struct inode *inode)
6623ec7c	29	{
6623ec7c JJ	30	if (S_ISLNK(inode->i_mode))
6623ec7c JJ	31	kfree(inode->i_link);
46c87441 AV	32	free_inode_nonrcu(inode);
	33	}
	34
6623ec7c JJ	35	static const struct super_operations securityfs_super_operations = {
6623ec7c JJ	36	.statfs = simple_statfs,
f614ee1e	37	.free_inode = securityfs_free_inode,
6623ec7c JJ	38	};
6623ec7c JJ	39
5c86d7e0	40	static int securityfs_fill_super(struct super_block sb, struct fs_context fc)
b67dbf9d	41	{
cda37124	42	static const struct tree_descr files[] = {{""}};
6623ec7c JJ	43	int error;
	44
	45	error = simple_fill_super(sb, SECURITYFS_MAGIC, files);
	46	if (error)
	47	return error;
	48
	49	sb->s_op = &securityfs_super_operations;
b67dbf9d	50
6623ec7c	51	return 0;
b67dbf9d GKH	52	}
b67dbf9d GKH	53
5c86d7e0	54	static int securityfs_get_tree(struct fs_context *fc)
b67dbf9d	55	{
5c86d7e0 DH	56	return get_tree_single(fc, securityfs_fill_super);
	57	}
	58
	59	static const struct fs_context_operations securityfs_context_ops = {
	60	.get_tree = securityfs_get_tree,
	61	};
	62
	63	static int securityfs_init_fs_context(struct fs_context *fc)
	64	{
	65	fc->ops = &securityfs_context_ops;
	66	return 0;
b67dbf9d GKH	67	}
	68
	69	static struct file_system_type fs_type = {
	70	.owner = THIS_MODULE,
	71	.name = "securityfs",
5c86d7e0	72	.init_fs_context = securityfs_init_fs_context,
b67dbf9d GKH	73	.kill_sb = kill_litter_super,
	74	};
	75
b67dbf9d	76	/**
6623ec7c	77	* securityfs_create_dentry - create a dentry in the securityfs filesystem
b67dbf9d GKH	78	*
	79	* @name: a pointer to a string containing the name of the file to create.
	80	* @mode: the permission that the file should have
	81	* @parent: a pointer to the parent dentry for this file. This should be a
3f23d815	82	* directory dentry if set. If this parameter is %NULL, then the
b67dbf9d GKH	83	* file will be created in the root of the securityfs filesystem.
b67dbf9d GKH	84	* @data: a pointer to something that the caller will want to get to later
8e18e294	85	* on. The inode.i_private pointer will point to this value on
b67dbf9d GKH	86	* the open() call.
	87	* @fops: a pointer to a struct file_operations that should be used for
	88	* this file.
6623ec7c JJ	89	* @iops: a point to a struct of inode_operations that should be used for
6623ec7c JJ	90	* this file/dir
b67dbf9d	91	*
6623ec7c JJ	92	* This is the basic "create a file/dir/symlink" function for
	93	* securityfs. It allows for a wide range of flexibility in creating
	94	* a file, or a directory (if you want to create a directory, the
	95	* securityfs_create_dir() function is recommended to be used
	96	* instead).
b67dbf9d	97	*
3f23d815	98	* This function returns a pointer to a dentry if it succeeds. This
6623ec7c JJ	99	* pointer must be passed to the securityfs_remove() function when the
	100	* file is to be removed (no automatic cleanup happens if your module
	101	* is unloaded, you are responsible here). If an error occurs, the
	102	* function will return the error value (via ERR_PTR).
b67dbf9d	103	*
3f23d815	104	* If securityfs is not enabled in the kernel, the value %-ENODEV is
faa3aad7	105	* returned.
b67dbf9d	106	*/
6623ec7c JJ	107	static struct dentry securityfs_create_dentry(const char name, umode_t mode,
	108	struct dentry parent, void data,
	109	const struct file_operations *fops,
	110	const struct inode_operations *iops)
b67dbf9d	111	{
3e25eb9c	112	struct dentry *dentry;
3e25eb9c	113	struct inode dir, inode;
b67dbf9d GKH	114	int error;
b67dbf9d GKH	115
6623ec7c	116	if (!(mode & S_IFMT))
3e25eb9c	117	mode = (mode & S_IALLUGO) \| S_IFREG;
3e25eb9c	118
b67dbf9d GKH	119	pr_debug("securityfs: creating file '%s'\n",name);
b67dbf9d GKH	120
1f5ce9e9	121	error = simple_pin_fs(&fs_type, &mount, &mount_count);
3e25eb9c AV	122	if (error)
	123	return ERR_PTR(error);
	124
	125	if (!parent)
	126	parent = mount->mnt_root;
	127
ce0b16dd	128	dir = d_inode(parent);
3e25eb9c	129
5955102c	130	inode_lock(dir);
3e25eb9c AV	131	dentry = lookup_one_len(name, parent, strlen(name));
	132	if (IS_ERR(dentry))
	133	goto out;
	134
ce0b16dd	135	if (d_really_is_positive(dentry)) {
3e25eb9c AV	136	error = -EEXIST;
3e25eb9c AV	137	goto out1;
b67dbf9d GKH	138	}
b67dbf9d GKH	139
3e25eb9c AV	140	inode = new_inode(dir->i_sb);
	141	if (!inode) {
	142	error = -ENOMEM;
	143	goto out1;
b67dbf9d GKH	144	}
b67dbf9d GKH	145
3e25eb9c AV	146	inode->i_ino = get_next_ino();
3e25eb9c AV	147	inode->i_mode = mode;
078cd827	148	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
3e25eb9c	149	inode->i_private = data;
6623ec7c	150	if (S_ISDIR(mode)) {
3e25eb9c AV	151	inode->i_op = &simple_dir_inode_operations;
	152	inode->i_fop = &simple_dir_operations;
	153	inc_nlink(inode);
	154	inc_nlink(dir);
6623ec7c JJ	155	} else if (S_ISLNK(mode)) {
	156	inode->i_op = iops ? iops : &simple_symlink_inode_operations;
	157	inode->i_link = data;
3e25eb9c AV	158	} else {
3e25eb9c AV	159	inode->i_fop = fops;
b67dbf9d	160	}
3e25eb9c AV	161	d_instantiate(dentry, inode);
3e25eb9c AV	162	dget(dentry);
5955102c	163	inode_unlock(dir);
3e25eb9c AV	164	return dentry;
	165
	166	out1:
	167	dput(dentry);
	168	dentry = ERR_PTR(error);
	169	out:
5955102c	170	inode_unlock(dir);
3e25eb9c	171	simple_release_fs(&mount, &mount_count);
b67dbf9d GKH	172	return dentry;
b67dbf9d GKH	173	}
6623ec7c JJ	174
	175	/**
	176	* securityfs_create_file - create a file in the securityfs filesystem
	177	*
	178	* @name: a pointer to a string containing the name of the file to create.
	179	* @mode: the permission that the file should have
	180	* @parent: a pointer to the parent dentry for this file. This should be a
	181	* directory dentry if set. If this parameter is %NULL, then the
	182	* file will be created in the root of the securityfs filesystem.
	183	* @data: a pointer to something that the caller will want to get to later
	184	* on. The inode.i_private pointer will point to this value on
	185	* the open() call.
	186	* @fops: a pointer to a struct file_operations that should be used for
	187	* this file.
	188	*
	189	* This function creates a file in securityfs with the given @name.
	190	*
	191	* This function returns a pointer to a dentry if it succeeds. This
	192	* pointer must be passed to the securityfs_remove() function when the file is
	193	* to be removed (no automatic cleanup happens if your module is unloaded,
	194	* you are responsible here). If an error occurs, the function will return
	195	* the error value (via ERR_PTR).
	196	*
	197	* If securityfs is not enabled in the kernel, the value %-ENODEV is
	198	* returned.
	199	*/
	200	struct dentry securityfs_create_file(const char name, umode_t mode,
	201	struct dentry parent, void data,
	202	const struct file_operations *fops)
	203	{
	204	return securityfs_create_dentry(name, mode, parent, data, fops, NULL);
	205	}
b67dbf9d GKH	206	EXPORT_SYMBOL_GPL(securityfs_create_file);
	207
	208	/**
	209	* securityfs_create_dir - create a directory in the securityfs filesystem
	210	*
	211	* @name: a pointer to a string containing the name of the directory to
	212	* create.
	213	* @parent: a pointer to the parent dentry for this file. This should be a
3f23d815	214	* directory dentry if set. If this parameter is %NULL, then the
b67dbf9d GKH	215	* directory will be created in the root of the securityfs filesystem.
b67dbf9d GKH	216	*
3f23d815	217	* This function creates a directory in securityfs with the given @name.
b67dbf9d	218	*
3f23d815	219	* This function returns a pointer to a dentry if it succeeds. This
b67dbf9d GKH	220	* pointer must be passed to the securityfs_remove() function when the file is
b67dbf9d GKH	221	* to be removed (no automatic cleanup happens if your module is unloaded,
1b460651 LG	222	* you are responsible here). If an error occurs, the function will return
1b460651 LG	223	* the error value (via ERR_PTR).
b67dbf9d	224	*
3f23d815	225	* If securityfs is not enabled in the kernel, the value %-ENODEV is
1b460651	226	* returned.
b67dbf9d GKH	227	*/
	228	struct dentry securityfs_create_dir(const char name, struct dentry *parent)
	229	{
6623ec7c	230	return securityfs_create_file(name, S_IFDIR \| 0755, parent, NULL, NULL);
b67dbf9d GKH	231	}
	232	EXPORT_SYMBOL_GPL(securityfs_create_dir);
	233
6623ec7c JJ	234	/**
	235	* securityfs_create_symlink - create a symlink in the securityfs filesystem
	236	*
	237	* @name: a pointer to a string containing the name of the symlink to
	238	* create.
	239	* @parent: a pointer to the parent dentry for the symlink. This should be a
	240	* directory dentry if set. If this parameter is %NULL, then the
	241	* directory will be created in the root of the securityfs filesystem.
	242	* @target: a pointer to a string containing the name of the symlink's target.
	243	* If this parameter is %NULL, then the @iops parameter needs to be
	244	* setup to handle .readlink and .get_link inode_operations.
	245	* @iops: a pointer to the struct inode_operations to use for the symlink. If
	246	* this parameter is %NULL, then the default simple_symlink_inode
	247	* operations will be used.
	248	*
	249	* This function creates a symlink in securityfs with the given @name.
	250	*
	251	* This function returns a pointer to a dentry if it succeeds. This
	252	* pointer must be passed to the securityfs_remove() function when the file is
	253	* to be removed (no automatic cleanup happens if your module is unloaded,
	254	* you are responsible here). If an error occurs, the function will return
	255	* the error value (via ERR_PTR).
	256	*
	257	* If securityfs is not enabled in the kernel, the value %-ENODEV is
	258	* returned.
	259	*/
	260	struct dentry securityfs_create_symlink(const char name,
	261	struct dentry *parent,
	262	const char *target,
	263	const struct inode_operations *iops)
	264	{
	265	struct dentry *dent;
	266	char *link = NULL;
	267
	268	if (target) {
	269	link = kstrdup(target, GFP_KERNEL);
	270	if (!link)
	271	return ERR_PTR(-ENOMEM);
	272	}
	273	dent = securityfs_create_dentry(name, S_IFLNK \| 0444, parent,
	274	link, NULL, iops);
	275	if (IS_ERR(dent))
	276	kfree(link);
	277
	278	return dent;
	279	}
	280	EXPORT_SYMBOL_GPL(securityfs_create_symlink);
	281
b67dbf9d GKH	282	/**
	283	* securityfs_remove - removes a file or directory from the securityfs filesystem
	284	*
3f23d815	285	* @dentry: a pointer to a the dentry of the file or directory to be removed.
b67dbf9d GKH	286	*
	287	* This function removes a file or directory in securityfs that was previously
	288	* created with a call to another securityfs function (like
	289	* securityfs_create_file() or variants thereof.)
	290	*
	291	* This function is required to be called in order for the file to be
3f23d815 RD	292	* removed. No automatic cleanup of files will happen when a module is
3f23d815 RD	293	* removed; you are responsible here.
b67dbf9d GKH	294	*/
	295	void securityfs_remove(struct dentry *dentry)
	296	{
4093d306	297	struct inode *dir;
b67dbf9d	298
d93e4c94	299	if (!dentry \|\| IS_ERR(dentry))
b67dbf9d GKH	300	return;
b67dbf9d GKH	301
4093d306 AV	302	dir = d_inode(dentry->d_parent);
4093d306 AV	303	inode_lock(dir);
dc3f4198 AV	304	if (simple_positive(dentry)) {
dc3f4198 AV	305	if (d_is_dir(dentry))
4093d306	306	simple_rmdir(dir, dentry);
dc3f4198	307	else
4093d306	308	simple_unlink(dir, dentry);
dc3f4198	309	dput(dentry);
b67dbf9d	310	}
4093d306	311	inode_unlock(dir);
b67dbf9d GKH	312	simple_release_fs(&mount, &mount_count);
	313	}
	314	EXPORT_SYMBOL_GPL(securityfs_remove);
	315
d69dece5 CS	316	#ifdef CONFIG_SECURITY
	317	static struct dentry *lsm_dentry;
	318	static ssize_t lsm_read(struct file filp, char __user buf, size_t count,
	319	loff_t *ppos)
	320	{
	321	return simple_read_from_buffer(buf, count, ppos, lsm_names,
	322	strlen(lsm_names));
	323	}
	324
	325	static const struct file_operations lsm_ops = {
	326	.read = lsm_read,
	327	.llseek = generic_file_llseek,
	328	};
	329	#endif
	330
b67dbf9d GKH	331	static int __init securityfs_init(void)
	332	{
	333	int retval;
	334
f9bb4882 EB	335	retval = sysfs_create_mount_point(kernel_kobj, "security");
	336	if (retval)
	337	return retval;
b67dbf9d GKH	338
b67dbf9d GKH	339	retval = register_filesystem(&fs_type);
d69dece5	340	if (retval) {
f9bb4882	341	sysfs_remove_mount_point(kernel_kobj, "security");
d69dece5 CS	342	return retval;
	343	}
	344	#ifdef CONFIG_SECURITY
	345	lsm_dentry = securityfs_create_file("lsm", 0444, NULL, NULL,
	346	&lsm_ops);
	347	#endif
	348	return 0;
b67dbf9d	349	}
b67dbf9d	350	core_initcall(securityfs_init);