From patchwork Wed Feb 3 09:07:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Rosenberg X-Patchwork-Id: 12063821 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19869C433DB for ; Wed, 3 Feb 2021 09:11:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BE74B64F53 for ; Wed, 3 Feb 2021 09:11:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232951AbhBCJKp (ORCPT ); Wed, 3 Feb 2021 04:10:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233280AbhBCJJN (ORCPT ); Wed, 3 Feb 2021 04:09:13 -0500 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0321C061794 for ; Wed, 3 Feb 2021 01:07:53 -0800 (PST) Received: by mail-pf1-x44a.google.com with SMTP id 137so15646080pfw.4 for ; Wed, 03 Feb 2021 01:07:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=aacYYvBrsO89246VG7kwqo+UEXeIJ89FcRhL6OJu++c=; b=pN/zjW9WW+TyD9lbKiOtFxDGJFcLXOUEk8mf4j4LL2nKVCYXWHgvcFMAIDORtfvxjR ab3D51qsSlSJFu8gkhH1ug3grudzV/43vairsH8wHF9Ox8zgf/d4SiVVCBN+3PrNqV0R YB2rujh4TnKXkkIiaDcAWTKoE4FtaH3x9IUUceBso37WVLyA+Rm4352hhfTAcvmLwxil xxmxtYhk/nI96yrAAvcZKKm5Kw7YJWrKOe7oYYPugQEROAh512qFLoJIWgW24rtDPOvL hdiNl7bLuddHHdxG+IQfcVfFT3bO2DKY2gKKdC6Rmc4zWzecF2ZeCFuHP9yYkjLckSk5 CFQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=aacYYvBrsO89246VG7kwqo+UEXeIJ89FcRhL6OJu++c=; b=fbPpHoOeEz1uWkMzZCPFOgdf8UH7zXaqX5jIrtUu8J91ATCQ4ge7dDPr/rLDO1wM6H Ud0A7C7/nzDYiOz7vWrhMutiRW2SE4Kg8dO5LZwM/wUbfUAOu5Qz1/EUx/vS0sfX617U 4URmn1SIe7FvYY7uiIaek7aqKbmXK7F2/6RaWlTVp8zLdZ8TAqkhzEaYfQk7cfl2tf0P VpWAe6DZ+EKFpgFRRkP2KILS2DMp+86QK7YdWOkQOcKFmU2HVj4Zjhe52YQ3+1p4xAe5 Zsc7X/WQoBM46jguols+D/KKAErlel8npWgODF8r4BfYXSvlPyXEWBms1WkfRTkvtwVj 6yWQ== X-Gm-Message-State: AOAM531svvNb2ebjE+zF74rFH/k9Kg4HovUyviDOv0q9NCgoiSShSsG+ aOgoEtjv7Ug/13XAdXHnTRQvXNKRDnA= X-Google-Smtp-Source: ABdhPJw5vmAJE95kY1WlsgmFy7c+dcSAbpT0DRm2voYp9n6Cnu4XTnhuwz73/Pa5zmYCrpk77Md1S67BpU8= Sender: "drosen via sendgmr" X-Received: from drosen.c.googlers.com ([fda3:e722:ac3:10:24:72f4:c0a8:4e6f]) (user=drosen job=sendgmr) by 2002:a17:90a:3b44:: with SMTP id t4mr87542pjf.1.1612343272973; Wed, 03 Feb 2021 01:07:52 -0800 (PST) Date: Wed, 3 Feb 2021 09:07:45 +0000 In-Reply-To: <20210203090745.4103054-1-drosen@google.com> Message-Id: <20210203090745.4103054-3-drosen@google.com> Mime-Version: 1.0 References: <20210203090745.4103054-1-drosen@google.com> X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH 2/2] ext4: Optimize match for casefolded encrypted dirs From: Daniel Rosenberg To: "Theodore Y . Ts'o" , Eric Biggers , Andreas Dilger , linux-ext4@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Gabriel Krisman Bertazi , kernel-team@android.com, Daniel Rosenberg , Paul Lawrence Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@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 Signed-off-by: Paul Lawrence --- 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 90a2c182e4d7..997f80cfe5df 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2637,9 +2637,9 @@ 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 @@ -2670,9 +2670,9 @@ 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, @@ -2689,9 +2689,9 @@ 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) @@ -2716,15 +2716,16 @@ 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 00b0b0cb4600..ff024bb613c0 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -799,7 +799,9 @@ 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; @@ -1364,19 +1366,21 @@ static 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 (!IS_CASEFOLDED(dir) || !dir->i_sb->s_encoding) { 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, @@ -1384,10 +1388,18 @@ 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 @@ -1417,16 +1429,12 @@ 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); @@ -2061,15 +2069,11 @@ 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_DIRENT_HASHES(de)->hash = cpu_to_le32(hinfo.hash); + EXT4_DIRENT_HASHES(de)->hash = cpu_to_le32(hinfo->hash); EXT4_DIRENT_HASHES(de)->minor_hash = - cpu_to_le32(hinfo.minor_hash); + cpu_to_le32(hinfo->minor_hash); } } @@ -2220,10 +2224,9 @@ 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);