From patchwork Fri Jan 17 21:42:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Rosenberg X-Patchwork-Id: 11339867 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 29A4017EA for ; Fri, 17 Jan 2020 21:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F269E214AF for ; Fri, 17 Jan 2020 21:43:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CXn4pZxO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729990AbgAQVnT (ORCPT ); Fri, 17 Jan 2020 16:43:19 -0500 Received: from mail-pg1-f201.google.com ([209.85.215.201]:38789 "EHLO mail-pg1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729972AbgAQVnS (ORCPT ); Fri, 17 Jan 2020 16:43:18 -0500 Received: by mail-pg1-f201.google.com with SMTP id l13so15180051pgt.5 for ; Fri, 17 Jan 2020 13:43:18 -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=WxgwVjypClb4wXBEnsFhPs7Md2cufBpre+u9WsKYw7I=; b=CXn4pZxOLuGC69Nz6+VELpBugZtMeU/+bpuehqeDRIvTgJ1+DTEzF6kAnUKvl/kdpv tH1ORxCZV8mfoQdBRjVVDCjzQGKEUzKuC9Fn0wiJOEdN1iK7doyl6jr02pV4L4pRtHY3 JAvZmdteNZl+3GhUhhKfY5puOczHxeAX/ZDHqtyZWovpSgo0ipRlpN3i6DMOWNQEmCxm RgOncLDTBFjfO93fHu0zE2K8yUE6NfrYSwL4N103piqajX4AE55PaR42jGXLnspE1BgQ LLQoLJYHoy/0AY/2poOlEsLlDTYraotXfoLEu85+AhDihvkjSNloELKjuZ0DaF84EHHV PCpw== 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=WxgwVjypClb4wXBEnsFhPs7Md2cufBpre+u9WsKYw7I=; b=F7NUjGVfiQLZr6QS/tzzPWSb6V4LbDUUkZyndQF/s60lyVGw0EKW6+t11nbpJN0xuj oVvNzM/HASC3zLFEJtxEC6TPC+DJfdyxWTCyjxhceAR2M54PTye2OVX8Y514bS/Mkj+d oc6Bq97dWSM/5uzZRqlgxPzmj0iDcEwDIQCrStg2rcAaM5TIGeIyEifXgReEPoWca30s /ce/X4Nb9vV7mEmsgE+5G7lb4kyxpJN0b21FkSzmL/tPjgrgY6L0vC2h2ljDrb5aj1dJ XOZZfMeztPcX28k+Ez3UNNAjIoE/UQRXutRAvZ/KWRuwin2cGNUJRiy+BNczRmwd+7C8 fynQ== X-Gm-Message-State: APjAAAURvswTSQ2wmo2OLkvj6wNvTCv5EjX/GcTiH6QalW2dNTbiLpPT xL2K1slcri4+VhbHAmBrXQavXiFbB3U= X-Google-Smtp-Source: APXvYqxJp/yPu39dSyYifPYGuJFQwiU24dAWTohyAP4bwt0cypS4daC77iVFCfvCJ4uEO0qPJpWRdUpk2tU= X-Received: by 2002:a63:770c:: with SMTP id s12mr49288598pgc.25.1579297398140; Fri, 17 Jan 2020 13:43:18 -0800 (PST) Date: Fri, 17 Jan 2020 13:42:46 -0800 In-Reply-To: <20200117214246.235591-1-drosen@google.com> Message-Id: <20200117214246.235591-10-drosen@google.com> Mime-Version: 1.0 References: <20200117214246.235591-1-drosen@google.com> X-Mailer: git-send-email 2.25.0.341.g760bfbb309-goog Subject: [PATCH v3 9/9] 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 Cc: 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 a70b4db05b745..6755eb30a89b7 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 a5ee76a14e3b7..6b63271978a0b 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); @@ -2036,15 +2044,11 @@ 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); } } @@ -2195,10 +2199,9 @@ 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);