From patchwork Tue Jan 28 23:03:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Rosenberg X-Patchwork-Id: 11355335 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ABE53924 for ; Tue, 28 Jan 2020 23:04:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 80CBC2465B for ; Tue, 28 Jan 2020 23:04:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="p3xievYC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726659AbgA1XEm (ORCPT ); Tue, 28 Jan 2020 18:04:42 -0500 Received: from mail-pf1-f202.google.com ([209.85.210.202]:54360 "EHLO mail-pf1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726671AbgA1XEf (ORCPT ); Tue, 28 Jan 2020 18:04:35 -0500 Received: by mail-pf1-f202.google.com with SMTP id v14so9469948pfm.21 for ; Tue, 28 Jan 2020 15:04:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=lKtpwaZKWL1neBB1NRO1dY7byN6w+Jp1l7lnT/R4Qwg=; b=p3xievYCqztxTXmXD7nJZEAigVvj3Lda/BhlRwqAqO3SHUrWy2KYwJJwqzA8kdttn8 3TIN0DSCPxI/tQj9BFFSLm5x3SCKosBBV/eNJr/2VeRvzqmfRGnotjqSAyndL+8WFt45 FkX3jQVFdZ8y4oYU8mXKWI2R4ERFZgPxktIQWSRfSxxvZ3bo7U6lWkYUiJ4lmO3/H7Rb 0STyMPQ6ZvSaQPRdK8Ao/z1soK7+JoyEfVcC7MSfrhsdalSrG0/9OK1giramiXMhLRQd Cu8SkgQXkfjMz2vFSlGeWDNfUmjVaXeoWo8gBcYGVT7wMS7I8+XCGB2JR4jiyvoKg9ZM o26g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=lKtpwaZKWL1neBB1NRO1dY7byN6w+Jp1l7lnT/R4Qwg=; b=oQhcZfwSrZqf1ylw1snzWyqRYjQbGRmeCsgOE6JH+YYdVS6x1MxN/Y59CuJ8UI36Y1 1gwgwJ7Zpwxo/LMCAgAhGHCZjUAUmC9jFuQ3o81CxmQzqW8Bp9wpjbV61iXwIpuO5/jU db6u2tNNhRWGotO9ViClVj0nOdCn83wY41FwfGxXQuOXJQFHfUiG3rnGyu5cwKsdDhCM z78g5OGxTWf6ZEETneWbV1BAeoXFCz0MmfcHlLp/JUxhjD1GTMgvrYLQOV+kaZ4tp6wE WPFAGhgCdwrecxlWLq2dyTgw0hQ81eY+du5QD/RoL6jgJNQ5D4rxRiiRkhT5MtKF/C+z zfSg== X-Gm-Message-State: APjAAAVCaq9QEw5JYFKzf4ik4GiwyHpe8oR0Upl9XQulQo8+C5UPmw6N qljkgQSqC3U+XojyWyhJFl9XymoFmf0= X-Google-Smtp-Source: APXvYqzwNNdtCy4iCwCQ2KSsoF41ni/QDiHqIzFEGbpe3KPgiI9lT4VFk2Fyd9CKHJyFxrWurF7cknATqZE= X-Received: by 2002:a63:5b0e:: with SMTP id p14mr28473962pgb.315.1580252674948; Tue, 28 Jan 2020 15:04:34 -0800 (PST) Date: Tue, 28 Jan 2020 15:03:28 -0800 In-Reply-To: <20200128230328.183524-1-drosen@google.com> Message-Id: <20200128230328.183524-6-drosen@google.com> Mime-Version: 1.0 References: <20200128230328.183524-1-drosen@google.com> X-Mailer: git-send-email 2.25.0.341.g760bfbb309-goog Subject: [PATCH v6 5/5] ext4: Optimize match for casefolded encrypted dirs From: Daniel Rosenberg To: "Theodore Ts'o" , linux-ext4@vger.kernel.org, Jaegeuk Kim , Chao Yu , linux-f2fs-devel@lists.sourceforge.net, Eric Biggers , linux-fscrypt@vger.kernel.org, Alexander Viro , Richard Weinberger Cc: linux-mtd@lists.infradead.org, Andreas Dilger , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Gabriel Krisman Bertazi , kernel-team@android.com, Daniel Rosenberg Sender: linux-fscrypt-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org Matching names with casefolded encrypting directories requires decrypting entries to confirm case since we are case preserving. We can avoid needing to decrypt if our hash values don't match. Signed-off-by: Daniel Rosenberg --- fs/ext4/ext4.h | 17 ++++++++------- fs/ext4/namei.c | 55 ++++++++++++++++++++++++++----------------------- 2 files changed, 38 insertions(+), 34 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 64c7375bc3f65..c69b2bd66b201 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2393,9 +2393,9 @@ extern unsigned ext4_free_clusters_after_init(struct super_block *sb, ext4_fsblk_t ext4_inode_to_goal_block(struct inode *); #ifdef CONFIG_UNICODE -extern void ext4_fname_setup_ci_filename(struct inode *dir, +extern int ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname, - struct fscrypt_str *fname); + struct ext4_filename *fname); #endif #ifdef CONFIG_FS_ENCRYPTION @@ -2426,9 +2426,9 @@ static inline int ext4_fname_setup_filename(struct inode *dir, ext4_fname_from_fscrypt_name(fname, &name); #ifdef CONFIG_UNICODE - ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name); + err = ext4_fname_setup_ci_filename(dir, iname, fname); #endif - return 0; + return err; } static inline int ext4_fname_prepare_lookup(struct inode *dir, @@ -2445,9 +2445,9 @@ static inline int ext4_fname_prepare_lookup(struct inode *dir, ext4_fname_from_fscrypt_name(fname, &name); #ifdef CONFIG_UNICODE - ext4_fname_setup_ci_filename(dir, &dentry->d_name, &fname->cf_name); + err = ext4_fname_setup_ci_filename(dir, &dentry->d_name, fname); #endif - return 0; + return err; } static inline void ext4_fname_free_filename(struct ext4_filename *fname) @@ -2472,15 +2472,16 @@ static inline int ext4_fname_setup_filename(struct inode *dir, int lookup, struct ext4_filename *fname) { + int err = 0; fname->usr_fname = iname; fname->disk_name.name = (unsigned char *) iname->name; fname->disk_name.len = iname->len; #ifdef CONFIG_UNICODE - ext4_fname_setup_ci_filename(dir, iname, &fname->cf_name); + err = ext4_fname_setup_ci_filename(dir, iname, fname); #endif - return 0; + return err; } static inline int ext4_fname_prepare_lookup(struct inode *dir, diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 4fc543f459aed..25541d08f648b 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -784,7 +784,9 @@ dx_probe(struct ext4_filename *fname, struct inode *dir, if (hinfo->hash_version <= DX_HASH_TEA) hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; - if (fname && fname_name(fname)) + /* hash is already computed for encrypted casefolded directory */ + if (fname && fname_name(fname) && + !(IS_ENCRYPTED(dir) && IS_CASEFOLDED(dir))) ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), hinfo); hash = hinfo->hash; @@ -1352,19 +1354,21 @@ int ext4_ci_compare(const struct inode *parent, const struct qstr *name, return ret; } -void ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname, - struct fscrypt_str *cf_name) +int ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname, + struct ext4_filename *name) { + struct fscrypt_str *cf_name = &name->cf_name; + struct dx_hash_info *hinfo = &name->hinfo; int len; if (!needs_casefold(dir)) { cf_name->name = NULL; - return; + return 0; } cf_name->name = kmalloc(EXT4_NAME_LEN, GFP_NOFS); if (!cf_name->name) - return; + return -ENOMEM; len = utf8_casefold(dir->i_sb->s_encoding, iname, cf_name->name, @@ -1372,10 +1376,18 @@ void ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname, if (len <= 0) { kfree(cf_name->name); cf_name->name = NULL; - return; } cf_name->len = (unsigned) len; + if (!IS_ENCRYPTED(dir)) + return 0; + hinfo->hash_version = DX_HASH_SIPHASH; + hinfo->seed = NULL; + if (cf_name->name) + ext4fs_dirhash(dir, cf_name->name, cf_name->len, hinfo); + else + ext4fs_dirhash(dir, iname->name, iname->len, hinfo); + return 0; } #endif @@ -1405,16 +1417,12 @@ static bool ext4_match(struct inode *parent, struct qstr cf = {.name = fname->cf_name.name, .len = fname->cf_name.len}; if (IS_ENCRYPTED(parent)) { - struct dx_hash_info hinfo; - - hinfo.hash_version = DX_HASH_SIPHASH; - hinfo.seed = NULL; - ext4fs_dirhash(parent, fname->cf_name.name, - fname_len(fname), &hinfo); - if (hinfo.hash != EXT4_DIRENT_HASH(de) || - hinfo.minor_hash != - EXT4_DIRENT_MINOR_HASH(de)) + if (fname->hinfo.hash != EXT4_DIRENT_HASH(de) || + fname->hinfo.minor_hash != + EXT4_DIRENT_MINOR_HASH(de)) { + return 0; + } } return !ext4_ci_compare(parent, &cf, de->name, de->name_len, true); @@ -2037,15 +2045,11 @@ void ext4_insert_dentry(struct inode *dir, de->name_len = fname_len(fname); memcpy(de->name, fname_name(fname), fname_len(fname)); if (ext4_hash_in_dirent(dir)) { - struct dx_hash_info hinfo; + struct dx_hash_info *hinfo = &fname->hinfo; - hinfo.hash_version = DX_HASH_SIPHASH; - hinfo.seed = NULL; - ext4fs_dirhash(dir, fname_usr_name(fname), - fname_len(fname), &hinfo); - EXT4_EXTENDED_DIRENT(de)->hash = cpu_to_le32(hinfo.hash); + EXT4_EXTENDED_DIRENT(de)->hash = cpu_to_le32(hinfo->hash); EXT4_EXTENDED_DIRENT(de)->minor_hash = - cpu_to_le32(hinfo.minor_hash); + cpu_to_le32(hinfo->minor_hash); } } @@ -2196,10 +2200,9 @@ static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, if (fname->hinfo.hash_version <= DX_HASH_TEA) fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; - if (ext4_hash_in_dirent(dir)) - ext4fs_dirhash(dir, fname_usr_name(fname), - fname_len(fname), &fname->hinfo); - else + + /* casefolded encrypted hashes are computed on fname setup */ + if (!ext4_hash_in_dirent(dir)) ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), &fname->hinfo);