1 files changed, 74 insertions, 174 deletions

diff --git a/security/inode.c b/security/inode.c
index acc6cf0d790..43ce6e19015 100644
--- a/security/inode.c
+++ b/security/inode.c
@@ -20,107 +20,11 @@
 #include <linux/init.h>
 #include <linux/namei.h>
 #include <linux/security.h>
-
-#define SECURITYFS_MAGIC	0x73636673
+#include <linux/magic.h>
 
 static struct vfsmount *mount;
 static int mount_count;
 
-/*
- * TODO:
- *   I think I can get rid of these default_file_ops, but not quite sure...
- */
-static ssize_t default_read_file(struct file *file, char __user *buf,
-				 size_t count, loff_t *ppos)
-{
-	return 0;
-}
-
-static ssize_t default_write_file(struct file *file, const char __user *buf,
-				   size_t count, loff_t *ppos)
-{
-	return count;
-}
-
-static int default_open(struct inode *inode, struct file *file)
-{
-	if (inode->i_private)
-		file->private_data = inode->i_private;
-
-	return 0;
-}
-
-static const struct file_operations default_file_ops = {
-	.read =		default_read_file,
-	.write =	default_write_file,
-	.open =		default_open,
-};
-
-static struct inode *get_inode(struct super_block *sb, int mode, dev_t dev)
-{
-	struct inode *inode = new_inode(sb);
-
-	if (inode) {
-		inode->i_mode = mode;
-		inode->i_uid = 0;
-		inode->i_gid = 0;
-		inode->i_blocks = 0;
-		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-		switch (mode & S_IFMT) {
-		default:
-			init_special_inode(inode, mode, dev);
-			break;
-		case S_IFREG:
-			inode->i_fop = &default_file_ops;
-			break;
-		case S_IFDIR:
-			inode->i_op = &simple_dir_inode_operations;
-			inode->i_fop = &simple_dir_operations;
-
-			/* directory inodes start off with i_nlink == 2 (for "." entry) */
-			inc_nlink(inode);
-			break;
-		}
-	}
-	return inode;
-}
-
-/* SMP-safe */
-static int mknod(struct inode *dir, struct dentry *dentry,
-			 int mode, dev_t dev)
-{
-	struct inode *inode;
-	int error = -EPERM;
-
-	if (dentry->d_inode)
-		return -EEXIST;
-
-	inode = get_inode(dir->i_sb, mode, dev);
-	if (inode) {
-		d_instantiate(dentry, inode);
-		dget(dentry);
-		error = 0;
-	}
-	return error;
-}
-
-static int mkdir(struct inode *dir, struct dentry *dentry, int mode)
-{
-	int res;
-
-	mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR;
-	res = mknod(dir, dentry, mode, 0);
-	if (!res)
-		inc_nlink(dir);
-	return res;
-}
-
-static int create(struct inode *dir, struct dentry *dentry, int mode)
-{
-	mode = (mode & S_IALLUGO) | S_IFREG;
-	return mknod(dir, dentry, mode, 0);
-}
-
 static inline int positive(struct dentry *dentry)
 {
 	return dentry->d_inode && !d_unhashed(dentry);
@@ -133,64 +37,27 @@ static int fill_super(struct super_block *sb, void *data, int silent)
 	return simple_fill_super(sb, SECURITYFS_MAGIC, files);
 }
 
-static int get_sb(struct file_system_type *fs_type,
+static struct dentry *get_sb(struct file_system_type *fs_type,
 		  int flags, const char *dev_name,
-		  void *data, struct vfsmount *mnt)
+		  void *data)
 {
-	return get_sb_single(fs_type, flags, data, fill_super, mnt);
+	return mount_single(fs_type, flags, data, fill_super);
 }
 
 static struct file_system_type fs_type = {
 	.owner =	THIS_MODULE,
 	.name =		"securityfs",
-	.get_sb =	get_sb,
+	.mount =	get_sb,
 	.kill_sb =	kill_litter_super,
 };
 
-static int create_by_name(const char *name, mode_t mode,
-			  struct dentry *parent,
-			  struct dentry **dentry)
-{
-	int error = 0;
-
-	*dentry = NULL;
-
-	/* If the parent is not specified, we create it in the root.
-	 * We need the root dentry to do this, which is in the super
-	 * block. A pointer to that is in the struct vfsmount that we
-	 * have around.
-	 */
-	if (!parent ) {
-		if (mount && mount->mnt_sb) {
-			parent = mount->mnt_sb->s_root;
-		}
-	}
-	if (!parent) {
-		pr_debug("securityfs: Ah! can not find a parent!\n");
-		return -EFAULT;
-	}
-
-	mutex_lock(&parent->d_inode->i_mutex);
-	*dentry = lookup_one_len(name, parent, strlen(name));
-	if (!IS_ERR(dentry)) {
-		if ((mode & S_IFMT) == S_IFDIR)
-			error = mkdir(parent->d_inode, *dentry, mode);
-		else
-			error = create(parent->d_inode, *dentry, mode);
-	} else
-		error = PTR_ERR(dentry);
-	mutex_unlock(&parent->d_inode->i_mutex);
-
-	return error;
-}
-
 /**
  * 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 paramater is NULL, then the
+ *          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
@@ -199,49 +66,83 @@ static int create_by_name(const char *name, mode_t mode,
  *        this file.
  *
  * This is the basic "create a file" function for securityfs.  It allows for a
- * wide range of flexibility in createing a file, or a directory (if you
+ * 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.)
+ * recommended to be used instead).
  *
- * This function will return a pointer to a dentry if it succeeds.  This
+ * 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, NULL will be returned.
+ * you are responsible here).  If an error occurs, the function will return
+ * the erorr value (via ERR_PTR).
  *
- * If securityfs is not enabled in the kernel, the value -ENODEV will be
- * returned.  It is not wise to check for this value, but rather, check for
- * NULL or !NULL instead as to eliminate the need for #ifdef in the calling
- * code.
+ * If securityfs is not enabled in the kernel, the value %-ENODEV is
+ * returned.
  */
-struct dentry *securityfs_create_file(const char *name, mode_t mode,
+struct dentry *securityfs_create_file(const char *name, umode_t mode,
 				   struct dentry *parent, void *data,
 				   const struct file_operations *fops)
 {
-	struct dentry *dentry = NULL;
+	struct dentry *dentry;
+	int is_dir = S_ISDIR(mode);
+	struct inode *dir, *inode;
 	int error;
 
+	if (!is_dir) {
+		BUG_ON(!fops);
+		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) {
-		dentry = ERR_PTR(error);
-		goto exit;
+	if (error)
+		return ERR_PTR(error);
+
+	if (!parent)
+		parent = mount->mnt_root;
+
+	dir = parent->d_inode;
+
+	mutex_lock(&dir->i_mutex);
+	dentry = lookup_one_len(name, parent, strlen(name));
+	if (IS_ERR(dentry))
+		goto out;
+
+	if (dentry->d_inode) {
+		error = -EEXIST;
+		goto out1;
 	}
 
-	error = create_by_name(name, mode, parent, &dentry);
-	if (error) {
-		dentry = ERR_PTR(error);
-		simple_release_fs(&mount, &mount_count);
-		goto exit;
+	inode = new_inode(dir->i_sb);
+	if (!inode) {
+		error = -ENOMEM;
+		goto out1;
 	}
 
-	if (dentry->d_inode) {
-		if (fops)
-			dentry->d_inode->i_fop = fops;
-		if (data)
-			dentry->d_inode->i_private = data;
+	inode->i_ino = get_next_ino();
+	inode->i_mode = mode;
+	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+	inode->i_private = data;
+	if (is_dir) {
+		inode->i_op = &simple_dir_inode_operations;
+		inode->i_fop = &simple_dir_operations;
+		inc_nlink(inode);
+		inc_nlink(dir);
+	} else {
+		inode->i_fop = fops;
 	}
-exit:
+	d_instantiate(dentry, inode);
+	dget(dentry);
+	mutex_unlock(&dir->i_mutex);
+	return dentry;
+
+out1:
+	dput(dentry);
+	dentry = ERR_PTR(error);
+out:
+	mutex_unlock(&dir->i_mutex);
+	simple_release_fs(&mount, &mount_count);
 	return dentry;
 }
 EXPORT_SYMBOL_GPL(securityfs_create_file);
@@ -252,19 +153,19 @@ EXPORT_SYMBOL_GPL(securityfs_create_file);
  * @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 paramater is NULL, then the
+ *          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 creates a directory in securityfs with the given @name.
  *
- * This function will return a pointer to a dentry if it succeeds.  This
+ * 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, NULL will be returned.
+ * you are responsible here).  If an error occurs, %NULL will be returned.
  *
- * If securityfs is not enabled in the kernel, the value -ENODEV will be
+ * If securityfs is not enabled in the kernel, the value %-ENODEV is
  * returned.  It is not wise to check for this value, but rather, check for
- * NULL or !NULL instead as to eliminate the need for #ifdef in the calling
+ * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
  * code.
  */
 struct dentry *securityfs_create_dir(const char *name, struct dentry *parent)
@@ -278,22 +179,21 @@ EXPORT_SYMBOL_GPL(securityfs_create_dir);
 /**
  * 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.
+ * @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.
+ * removed. No automatic cleanup of files will happen when a module is
+ * removed; you are responsible here.
  */
 void securityfs_remove(struct dentry *dentry)
 {
 	struct dentry *parent;
 
-	if (!dentry)
+	if (!dentry || IS_ERR(dentry))
 		return;
 
 	parent = dentry->d_parent;