diff options
| -rw-r--r-- | security/inode.c | 191 |
1 files changed, 50 insertions, 141 deletions
diff --git a/security/inode.c b/security/inode.c index 90a70a67d83..43ce6e19015 100644 --- a/security/inode.c +++ b/security/inode.c @@ -25,100 +25,6 @@ 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, - .llseek = noop_llseek, -}; - -static struct inode *get_inode(struct super_block *sb, umode_t mode, dev_t dev) -{ - struct inode *inode = new_inode(sb); - - if (inode) { - inode->i_ino = get_next_ino(); - inode->i_mode = mode; - 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, - umode_t mode, dev_t dev) -{ - struct inode *inode; - int error = -ENOMEM; - - 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, umode_t 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, umode_t 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); @@ -145,38 +51,6 @@ static struct file_system_type fs_type = { .kill_sb = kill_litter_super, }; -static int create_by_name(const char *name, umode_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) - parent = mount->mnt_root; - - mutex_lock(&parent->d_inode->i_mutex); - *dentry = lookup_one_len(name, parent, strlen(name)); - if (!IS_ERR(*dentry)) { - if (S_ISDIR(mode)) - error = mkdir(parent->d_inode, *dentry, mode); - else - error = create(parent->d_inode, *dentry, mode); - if (error) - dput(*dentry); - } else - error = PTR_ERR(*dentry); - mutex_unlock(&parent->d_inode->i_mutex); - - return error; -} - /** * securityfs_create_file - create a file in the securityfs filesystem * @@ -209,31 +83,66 @@ 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); |