From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5BF1C433EF for ; Thu, 19 May 2022 01:41:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232572AbiESBl0 (ORCPT ); Wed, 18 May 2022 21:41:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46150 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232535AbiESBlS (ORCPT ); Wed, 18 May 2022 21:41:18 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8FE268321 for ; Wed, 18 May 2022 18:41:15 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 888681F45360 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1652924474; bh=pcjKG6wHiQeuQuzQSULJ4O9VgPD1+aNrTuVsHE/YnG8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZSD/pC83ikVCg8CH8jGR6dE1o5x+opcH6JUV1a9HHvmSKz9Qhi+k70VMqX9FZqM5O 4HiIv6saXrI0ASHjt/wYgrNjWRWDzKaC04/F4WSTZrlsj92L0HWkNfQ8FHG7Hky5YX Or5oZqhonwGarvRvdnHsXMLaWNrZVSWF1dPwWQRWr1uvbhE6ogRCNV4Ht2Hk05ZiDs 5YIXMHIQNvEkUsJPDgZJQueKok6UAfmqWkdouI1rAgru3vNCf+kUkMz1ArwyXidZGp KwQnilR5HKpeRnGQYJj12LTYuRbquBBMibRHtfVlY+7isY14dVlDPte2Og+Pu9njEM qSwQyMIRBITKg== From: Gabriel Krisman Bertazi To: tytso@mit.edu, adilger.kernel@dilger.ca, jaegeuk@kernel.org, ebiggers@kernel.org Cc: linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Gabriel Krisman Bertazi , kernel@collabora.com Subject: [PATCH v6 4/8] ext4: Reuse generic_ci_match for ci comparisons Date: Wed, 18 May 2022 21:40:40 -0400 Message-Id: <20220519014044.508099-5-krisman@collabora.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220519014044.508099-1-krisman@collabora.com> References: <20220519014044.508099-1-krisman@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Instead of reimplementing ext4_match_ci, use the new libfs helper. It should be fine to drop the fname->cf_name in the encrypted directory case for the hash verification optimization because the only two ways for fname->cf_name to be NULL on a case-insensitive lookup is (1) if name under lookup has an invalid encoding and the FS is not in strict mode; or (2) if the directory is encrypted and we don't have the key. For case (1), it doesn't matter, because the lookup hash will be generated with fname->usr_name, the same as the disk (fallback to invalid encoding behavior on !strict mode). Case (2) is caught by the previous check (!IS_ENCRYPTED(parent) || fscrypt_has_encryption_key(parent)), so we never reach this code. Signed-off-by: Gabriel Krisman Bertazi --- fs/ext4/namei.c | 81 +++++++++++-------------------------------------- 1 file changed, 17 insertions(+), 64 deletions(-) diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 206fcf8fdc16..98295b03a57c 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1318,58 +1318,6 @@ static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) } #if IS_ENABLED(CONFIG_UNICODE) -/* - * Test whether a case-insensitive directory entry matches the filename - * being searched for. If quick is set, assume the name being looked up - * is already in the casefolded form. - * - * Returns: 0 if the directory entry matches, more than 0 if it - * doesn't match or less than zero on error. - */ -static int ext4_ci_compare(const struct inode *parent, const struct qstr *name, - u8 *de_name, size_t de_name_len, bool quick) -{ - const struct super_block *sb = parent->i_sb; - const struct unicode_map *um = sb->s_encoding; - struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len); - struct qstr entry = QSTR_INIT(de_name, de_name_len); - int ret; - - if (IS_ENCRYPTED(parent)) { - const struct fscrypt_str encrypted_name = - FSTR_INIT(de_name, de_name_len); - - decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL); - if (!decrypted_name.name) - return -ENOMEM; - ret = fscrypt_fname_disk_to_usr(parent, 0, 0, &encrypted_name, - &decrypted_name); - if (ret < 0) - goto out; - entry.name = decrypted_name.name; - entry.len = decrypted_name.len; - } - - if (quick) - ret = utf8_strncasecmp_folded(um, name, &entry); - else - ret = utf8_strncasecmp(um, name, &entry); - if (ret < 0) { - /* Handle invalid character sequence as either an error - * or as an opaque byte sequence. - */ - if (sb_has_strict_encoding(sb)) - ret = -EINVAL; - else if (name->len != entry.len) - ret = 1; - else - ret = !!memcmp(name->name, entry.name, entry.len); - } -out: - kfree(decrypted_name.name); - return ret; -} - int ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname, struct ext4_filename *name) { @@ -1432,20 +1380,25 @@ static bool ext4_match(struct inode *parent, #if IS_ENABLED(CONFIG_UNICODE) if (parent->i_sb->s_encoding && IS_CASEFOLDED(parent) && (!IS_ENCRYPTED(parent) || fscrypt_has_encryption_key(parent))) { - if (fname->cf_name.name) { - if (IS_ENCRYPTED(parent)) { - if (fname->hinfo.hash != EXT4_DIRENT_HASH(de) || - fname->hinfo.minor_hash != - EXT4_DIRENT_MINOR_HASH(de)) { + int ret; - return false; - } - } - return !ext4_ci_compare(parent, &fname->cf_name, - de->name, de->name_len, true); + if (IS_ENCRYPTED(parent) && + (fname->hinfo.hash != EXT4_DIRENT_HASH(de) || + fname->hinfo.minor_hash != EXT4_DIRENT_MINOR_HASH(de))) + return false; + + ret = generic_ci_match(parent, fname->usr_fname, + &fname->cf_name, de->name, + de->name_len); + if (ret < 0) { + /* + * Treat comparison errors as not a match. The + * only case where it happens is on a disk + * corruption or ENOMEM. + */ + return false; } - return !ext4_ci_compare(parent, fname->usr_fname, de->name, - de->name_len, false); + return ret; } #endif -- 2.36.1