From: Harry Papaxenopoulos Subject: [Resubmit][PATCH 4/5] Secure Deletion and Trash-Bin Support for Ext4 Date: Wed, 31 Jan 2007 09:55:08 -0500 (EST) Message-ID: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: ezk@cs.sunysb.edu, kolya@cs.sunysb.edu To: linux-ext4@vger.kernel.org Return-path: Received: from sbcs.cs.sunysb.edu ([130.245.1.15]:59790 "EHLO sbcs.cs.sunysb.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933318AbXAaOzL (ORCPT ); Wed, 31 Jan 2007 09:55:11 -0500 Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Trash-Bin Functionality for the ext4 filesystem: Signed-off-by: Harry Papaxenopoulos Signed-off-by: Nikolai Joukov Signed-off-by: Erez Zadok Index: sdfs/src/linux-2.6.20-rc6-trashbin/fs/ext4/super.c =================================================================== --- sdfs.orig/src/linux-2.6.20-rc6-trashbin/fs/ext4/super.c +++ sdfs/src/linux-2.6.20-rc6-trashbin/fs/ext4/super.c @@ -35,6 +35,7 @@ #include #include #include +#include #include @@ -1846,6 +1847,11 @@ static int ext4_fill_super (struct super goto failed_mount4; } +#ifdef CONFIG_EXT4DEV_FS_TRASHBIN + if ((sb->s_flags & MNT_TRASHBIN) && vfs_create_trash_bin(sb)) + goto failed_mount4; +#endif + ext4_setup_super (sb, es, sb->s_flags & MS_RDONLY); /* * akpm: core read_super() calls in here with the superblock locked. Index: sdfs/src/linux-2.6.20-rc6-trashbin/fs/ext4/namei.c =================================================================== --- sdfs.orig/src/linux-2.6.20-rc6-trashbin/fs/ext4/namei.c +++ sdfs/src/linux-2.6.20-rc6-trashbin/fs/ext4/namei.c @@ -37,6 +37,8 @@ #include #include #include +#include +#include #include "namei.h" #include "xattr.h" @@ -2077,6 +2079,10 @@ static int ext4_unlink(struct inode * di struct buffer_head * bh; struct ext4_dir_entry_2 * de; handle_t *handle; + int trashed = 0; +#ifdef CONFIG_EXT4DEV_FS_TRASHBIN + struct dentry *user_dentry = NULL; +#endif /* Initialize quotas before so that eventual writes go * in separate transaction */ @@ -2105,13 +2111,41 @@ static int ext4_unlink(struct inode * di inode->i_ino, inode->i_nlink); inode->i_nlink = 1; } - retval = ext4_delete_entry(handle, dir, de, bh); +#ifdef CONFIG_EXT4DEV_FS_TRASHBIN + if ((dentry->d_inode->i_sb->s_flags & MNT_TRASHBIN) && + (EXT4_I(dentry->d_inode)->i_flags & + (EXT4_UNRM_FL | EXT4_SECRM_FL))) { + + /* + * We put this code here to optimize the common case. Since + * lookups are expensive, we try to reserve from making any, + * unless one of the trash-bin flags are set. The cleanest + * way though is to probably move this code outside the + * above if statement. + */ + user_dentry = vfs_get_user_dentry(dir, 1); + if (IS_ERR(user_dentry)) { + retval = PTR_ERR(user_dentry); + user_dentry = NULL; + goto end_unlink; + } + + if (inode->i_nlink == 1 && user_dentry->d_inode && + user_dentry->d_inode->i_ino != dir->i_ino) { + retval = vfs_trash_entry(dir, dentry); + trashed = 1; + } + } +#endif + if (!trashed) + retval = ext4_delete_entry(handle, dir, de, bh); if (retval) goto end_unlink; dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; ext4_update_dx_flag(dir); ext4_mark_inode_dirty(handle, dir); - drop_nlink(inode); + if (!trashed) + drop_nlink(inode); if (!inode->i_nlink) ext4_orphan_add(handle, inode); inode->i_ctime = dir->i_ctime; @@ -2121,6 +2155,10 @@ static int ext4_unlink(struct inode * di end_unlink: ext4_journal_stop(handle); brelse (bh); +#ifdef CONFIG_EXT4DEV_FS_TRASHBIN + if (user_dentry) + dput(user_dentry); +#endif return retval; } Index: sdfs/src/linux-2.6.20-rc6-trashbin/fs/Kconfig =================================================================== --- sdfs.orig/src/linux-2.6.20-rc6-trashbin/fs/Kconfig +++ sdfs/src/linux-2.6.20-rc6-trashbin/fs/Kconfig @@ -227,6 +227,15 @@ config EXT4DEV_FS_SECURITY If you are not using a security module that requires using extended attributes for file security labels, say N. +config EXT4DEV_FS_TRASHBIN + bool "Ext4 trashbin functionality" + depends on TRASHBIN + depends on EXT4DEV_FS + help + Trashbin functionality for the ext4 filesystem + + If unsure, say N. + config JBD tristate help