From patchwork Fri Jun 26 06:09:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tetsuhiro Kohada X-Patchwork-Id: 11626577 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 2B0711392 for ; Fri, 26 Jun 2020 06:10:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 008A82080C for ; Fri, 26 Jun 2020 06:10:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="JINu5zP8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726661AbgFZGKH (ORCPT ); Fri, 26 Jun 2020 02:10:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725306AbgFZGKH (ORCPT ); Fri, 26 Jun 2020 02:10:07 -0400 Received: from mail-pl1-x644.google.com (mail-pl1-x644.google.com [IPv6:2607:f8b0:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 10EDEC08C5C1; Thu, 25 Jun 2020 23:10:07 -0700 (PDT) Received: by mail-pl1-x644.google.com with SMTP id bh7so3877317plb.11; Thu, 25 Jun 2020 23:10:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=0GkhNt6JHaeDg/KOivBzaYViQHGtdYS7S+DIM0YJHQM=; b=JINu5zP8rOsBatZpzUC9YYEKaRUVdkHhBecXaIx5sLHag9CzFXaxcAeACc8Ul2Zoho Wd0zUjz8TP1VPxalHLHf3BaRT6YnUL18iQY3Ijl6TY5yjZJPFdY8caUH9AzZWgSDn+nz ocXhY4SqV4WQtpe2cF5ffOhhICteMWUKjqTxu+LcH5vT34PB49/gP5AyEavFk5k+hTsh pYgRwRooz2L/IQzQXfLVsZm8yq6m1ovq+eBSqTvJKwW0HOW4Ad3mE+ORJCOKm6OEAf+n V7pFSqF7Vgu80H9Y076vUmKOHTcH4iBW20HPdc4+TwUNaFUVBnkOwxxTyR5/U+4skgLT nFCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=0GkhNt6JHaeDg/KOivBzaYViQHGtdYS7S+DIM0YJHQM=; b=qVNZ4lhg7auZ3JXKSkt+/AtJrPIl07fk0/idBE/9Vo/aVkksTlQFKHfVMmiKHt3d8I x1BWBNGX4NrTQwACfMjbz0H6Hhw4zj7S3cUgqsQm+O2p0EZl/5ZpfWI/iVEZkwKJ9KLx peGUB6Ncx8Chor5BvbttSkC9Al6Ffuj3vHGWBE5LIOiglkPZKtO3Xq4fR2Hja+Goddfz Dz6NjX0Ax73ZjVPnXTL6aRGRHQiFTsLZPv++7WROKIp07FCQx87qHhxW4qOCbHRdH+Qz lSqP9/mvIw2p/W9fEJTujIyiKW0bT6liERHh0Z6hRyM/MfWFEa3QjiuMgc5Z8dNdyo8t jYxQ== X-Gm-Message-State: AOAM533SNa5hoKpqoc1oUSm6W9cSLsr2eQbnBDhe1dBUieGVyGNhw54S bV58Yx3JbQFiDrQhqR81dwA= X-Google-Smtp-Source: ABdhPJxPplkerxSavZoPtGoU/OsBxy09QHNZ0xcq1pnmp/zrYb541eigQ4eGxFyMl5+Z8ycB4qtHsA== X-Received: by 2002:a17:90a:ad87:: with SMTP id s7mr1768955pjq.225.1593151806205; Thu, 25 Jun 2020 23:10:06 -0700 (PDT) Received: from dc803.localdomain (FL1-125-199-162-203.hyg.mesh.ad.jp. [125.199.162.203]) by smtp.gmail.com with ESMTPSA id w18sm25017230pfq.121.2020.06.25.23.10.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Jun 2020 23:10:05 -0700 (PDT) From: Tetsuhiro Kohada To: kohada.t2@gmail.com Cc: kohada.tetsuhiro@dc.mitsubishielectric.co.jp, mori.takahiro@ab.mitsubishielectric.co.jp, motai.hirotaka@aj.mitsubishielectric.co.jp, Sungjong Seo , Namjae Jeon , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC]PATCH] exfat: integrates dir-entry getting and validation Date: Fri, 26 Jun 2020 15:09:47 +0900 Message-Id: <20200626060947.24709-1-kohada.t2@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Add validation for num, bh and type on getting dir-entry. ('file' and 'stream-ext' dir-entries are pre-validated to ensure success) Renamed exfat_get_dentry_cached() to exfat_get_validated_dentry() due to a change in functionality. Integrate type-validation with simplified. This will also recognize a dir-entry set that contains 'benign secondary' dir-entries. And, rename TYPE_EXTEND to TYPE_NAME. Suggested-by: Sungjong Seo Signed-off-by: Tetsuhiro Kohada --- fs/exfat/dir.c | 144 ++++++++++++++++++-------------------------- fs/exfat/exfat_fs.h | 15 +++-- fs/exfat/file.c | 4 +- fs/exfat/inode.c | 6 +- fs/exfat/namei.c | 4 +- 5 files changed, 73 insertions(+), 100 deletions(-) diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index f4cea9a7fd02..e029e0986edc 100644 --- a/fs/exfat/dir.c +++ b/fs/exfat/dir.c @@ -33,6 +33,7 @@ static void exfat_get_uniname_from_ext_entry(struct super_block *sb, { int i; struct exfat_entry_set_cache *es; + struct exfat_dentry *ep; es = exfat_get_dentry_set(sb, p_dir, entry, ES_ALL_ENTRIES); if (!es) @@ -44,13 +45,9 @@ static void exfat_get_uniname_from_ext_entry(struct super_block *sb, * Third entry : first file-name entry * So, the index of first file-name dentry should start from 2. */ - for (i = 2; i < es->num_entries; i++) { - struct exfat_dentry *ep = exfat_get_dentry_cached(es, i); - - /* end of name entry */ - if (exfat_get_entry_type(ep) != TYPE_EXTEND) - break; + i = 2; + while ((ep = exfat_get_validated_dentry(es, i++, TYPE_NAME))) { exfat_extract_uni_name(ep, uniname); uniname += EXFAT_FILE_NAME_LEN; } @@ -372,7 +369,7 @@ unsigned int exfat_get_entry_type(struct exfat_dentry *ep) if (ep->type == EXFAT_STREAM) return TYPE_STREAM; if (ep->type == EXFAT_NAME) - return TYPE_EXTEND; + return TYPE_NAME; if (ep->type == EXFAT_ACL) return TYPE_ACL; return TYPE_CRITICAL_SEC; @@ -388,7 +385,7 @@ static void exfat_set_entry_type(struct exfat_dentry *ep, unsigned int type) ep->type &= EXFAT_DELETE; } else if (type == TYPE_STREAM) { ep->type = EXFAT_STREAM; - } else if (type == TYPE_EXTEND) { + } else if (type == TYPE_NAME) { ep->type = EXFAT_NAME; } else if (type == TYPE_BITMAP) { ep->type = EXFAT_BITMAP; @@ -421,7 +418,7 @@ static void exfat_init_name_entry(struct exfat_dentry *ep, { int i; - exfat_set_entry_type(ep, TYPE_EXTEND); + exfat_set_entry_type(ep, TYPE_NAME); ep->dentry.name.flags = 0x0; for (i = 0; i < EXFAT_FILE_NAME_LEN; i++) { @@ -594,12 +591,12 @@ void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es) struct exfat_dentry *ep; for (i = 0; i < es->num_entries; i++) { - ep = exfat_get_dentry_cached(es, i); + ep = exfat_get_validated_dentry(es, i, TYPE_ALL); chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum, chksum_type); chksum_type = CS_DEFAULT; } - ep = exfat_get_dentry_cached(es, 0); + ep = exfat_get_validated_dentry(es, 0, TYPE_FILE); ep->dentry.file.checksum = cpu_to_le16(chksum); es->modified = true; } @@ -741,92 +738,66 @@ struct exfat_dentry *exfat_get_dentry(struct super_block *sb, return (struct exfat_dentry *)((*bh)->b_data + off); } -enum exfat_validate_dentry_mode { - ES_MODE_STARTED, - ES_MODE_GET_FILE_ENTRY, - ES_MODE_GET_STRM_ENTRY, - ES_MODE_GET_NAME_ENTRY, - ES_MODE_GET_CRITICAL_SEC_ENTRY, -}; - -static bool exfat_validate_entry(unsigned int type, - enum exfat_validate_dentry_mode *mode) -{ - if (type == TYPE_UNUSED || type == TYPE_DELETED) - return false; - - switch (*mode) { - case ES_MODE_STARTED: - if (type != TYPE_FILE && type != TYPE_DIR) - return false; - *mode = ES_MODE_GET_FILE_ENTRY; - return true; - case ES_MODE_GET_FILE_ENTRY: - if (type != TYPE_STREAM) - return false; - *mode = ES_MODE_GET_STRM_ENTRY; - return true; - case ES_MODE_GET_STRM_ENTRY: - if (type != TYPE_EXTEND) - return false; - *mode = ES_MODE_GET_NAME_ENTRY; - return true; - case ES_MODE_GET_NAME_ENTRY: - if (type == TYPE_STREAM) - return false; - if (type != TYPE_EXTEND) { - if (!(type & TYPE_CRITICAL_SEC)) - return false; - *mode = ES_MODE_GET_CRITICAL_SEC_ENTRY; - } - return true; - case ES_MODE_GET_CRITICAL_SEC_ENTRY: - if (type == TYPE_EXTEND || type == TYPE_STREAM) - return false; - if ((type & TYPE_CRITICAL_SEC) != TYPE_CRITICAL_SEC) - return false; - return true; - default: - WARN_ON_ONCE(1); - return false; - } -} - -struct exfat_dentry *exfat_get_dentry_cached( - struct exfat_entry_set_cache *es, int num) +struct exfat_dentry *exfat_get_validated_dentry(struct exfat_entry_set_cache *es, + int num, unsigned int type) { int off = es->start_off + num * DENTRY_SIZE; - struct buffer_head *bh = es->bh[EXFAT_B_TO_BLK(off, es->sb)]; - char *p = bh->b_data + EXFAT_BLK_OFFSET(off, es->sb); + struct buffer_head *bh; + struct exfat_dentry *ep; - return (struct exfat_dentry *)p; + if (num >= es->num_entries) + return NULL; + + bh = es->bh[EXFAT_B_TO_BLK(off, es->sb)]; + if (!bh) + return NULL; + + ep = (struct exfat_dentry *) + (bh->b_data + EXFAT_BLK_OFFSET(off, es->sb)); + + switch (type) { + case TYPE_ALL: /* accept any */ + break; + case TYPE_FILE: + if (ep->type != EXFAT_FILE) + return NULL; + break; + case TYPE_SECONDARY: + if (!(type & exfat_get_entry_type(ep))) + return NULL; + break; + default: + if (type != exfat_get_entry_type(ep)) + return NULL; + } + return ep; } /* * Returns a set of dentries for a file or dir. * - * Note It provides a direct pointer to bh->data via exfat_get_dentry_cached(). + * Note It provides a direct pointer to bh->data via exfat_get_validated_dentry(). * User should call exfat_get_dentry_set() after setting 'modified' to apply * changes made in this entry set to the real device. * * in: * sb+p_dir+entry: indicates a file/dir - * type: specifies how many dentries should be included. + * max_entries: specifies how many dentries should be included. * return: * pointer of entry set on success, * NULL on failure. + * note: + * On success, guarantee the correct 'file' and 'stream-ext' dir-entries. */ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, - struct exfat_chain *p_dir, int entry, unsigned int type) + struct exfat_chain *p_dir, int entry, int max_entries) { int ret, i, num_bh; - unsigned int off, byte_offset, clu = 0; + unsigned int byte_offset, clu = 0; sector_t sec; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct exfat_entry_set_cache *es; struct exfat_dentry *ep; - int num_entries; - enum exfat_validate_dentry_mode mode = ES_MODE_STARTED; struct buffer_head *bh; if (p_dir->dir == DIR_DELETED) { @@ -844,13 +815,13 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, return NULL; es->sb = sb; es->modified = false; + es->num_entries = 1; /* byte offset in cluster */ byte_offset = EXFAT_CLU_OFFSET(byte_offset, sbi); /* byte offset in sector */ - off = EXFAT_BLK_OFFSET(byte_offset, sb); - es->start_off = off; + es->start_off = EXFAT_BLK_OFFSET(byte_offset, sb); /* sector offset in cluster */ sec = EXFAT_B_TO_BLK(byte_offset, sb); @@ -861,15 +832,12 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, goto free_es; es->bh[es->num_bh++] = bh; - ep = exfat_get_dentry_cached(es, 0); - if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode)) + ep = exfat_get_validated_dentry(es, 0, TYPE_FILE); + if (!ep) goto free_es; + es->num_entries = min(ep->dentry.file.num_ext + 1, max_entries); - num_entries = type == ES_ALL_ENTRIES ? - ep->dentry.file.num_ext + 1 : type; - es->num_entries = num_entries; - - num_bh = EXFAT_B_TO_BLK_ROUND_UP(off + num_entries * DENTRY_SIZE, sb); + num_bh = EXFAT_B_TO_BLK_ROUND_UP(es->start_off + es->num_entries * DENTRY_SIZE, sb); for (i = 1; i < num_bh; i++) { /* get the next sector */ if (exfat_is_last_sector_in_cluster(sbi, sec)) { @@ -889,11 +857,13 @@ struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, } /* validiate cached dentries */ - for (i = 1; i < num_entries; i++) { - ep = exfat_get_dentry_cached(es, i); - if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode)) + for (i = 1; i < es->num_entries; i++) { + if (!exfat_get_validated_dentry(es, i, TYPE_SECONDARY)) goto free_es; } + if (!exfat_get_validated_dentry(es, 1, TYPE_STREAM)) + goto free_es; + return es; free_es: @@ -1028,7 +998,7 @@ int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei, } brelse(bh); - if (entry_type == TYPE_EXTEND) { + if (entry_type == TYPE_NAME) { unsigned short entry_uniname[16], unichar; if (step != DIRENT_STEP_NAME) { @@ -1144,7 +1114,7 @@ int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir, type = exfat_get_entry_type(ext_ep); brelse(bh); - if (type == TYPE_EXTEND || type == TYPE_STREAM) + if (type == TYPE_NAME || type == TYPE_STREAM) count++; else break; diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h index 3aed8e22087a..93e11908d28d 100644 --- a/fs/exfat/exfat_fs.h +++ b/fs/exfat/exfat_fs.h @@ -40,7 +40,7 @@ enum { * Type Definitions */ #define ES_2_ENTRIES 2 -#define ES_ALL_ENTRIES 0 +#define ES_ALL_ENTRIES 256 #define DIR_DELETED 0xFFFF0321 @@ -56,7 +56,7 @@ enum { #define TYPE_FILE 0x011F #define TYPE_CRITICAL_SEC 0x0200 #define TYPE_STREAM 0x0201 -#define TYPE_EXTEND 0x0202 +#define TYPE_NAME 0x0202 #define TYPE_ACL 0x0203 #define TYPE_BENIGN_PRI 0x0400 #define TYPE_GUID 0x0401 @@ -65,6 +65,9 @@ enum { #define TYPE_BENIGN_SEC 0x0800 #define TYPE_ALL 0x0FFF +#define TYPE_PRIMARY (TYPE_CRITICAL_PRI | TYPE_BENIGN_PRI) +#define TYPE_SECONDARY (TYPE_CRITICAL_SEC | TYPE_BENIGN_SEC) + #define MAX_CHARSET_SIZE 6 /* max size of multi-byte character */ #define MAX_NAME_LENGTH 255 /* max len of file name excluding NULL */ #define MAX_VFSNAME_BUF_SIZE ((MAX_NAME_LENGTH + 1) * MAX_CHARSET_SIZE) @@ -171,7 +174,7 @@ struct exfat_entry_set_cache { unsigned int start_off; int num_bh; struct buffer_head *bh[DIR_CACHE_SIZE]; - unsigned int num_entries; + int num_entries; }; struct exfat_dir_entry { @@ -456,10 +459,10 @@ int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir, struct exfat_dentry *exfat_get_dentry(struct super_block *sb, struct exfat_chain *p_dir, int entry, struct buffer_head **bh, sector_t *sector); -struct exfat_dentry *exfat_get_dentry_cached(struct exfat_entry_set_cache *es, - int num); +struct exfat_dentry *exfat_get_validated_dentry(struct exfat_entry_set_cache *es, + int num, unsigned int type); struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, - struct exfat_chain *p_dir, int entry, unsigned int type); + struct exfat_chain *p_dir, int entry, int max_entries); int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync); int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir); diff --git a/fs/exfat/file.c b/fs/exfat/file.c index 6707f3eb09b5..b6b458e6f5e3 100644 --- a/fs/exfat/file.c +++ b/fs/exfat/file.c @@ -160,8 +160,8 @@ int __exfat_truncate(struct inode *inode, loff_t new_size) ES_ALL_ENTRIES); if (!es) return -EIO; - ep = exfat_get_dentry_cached(es, 0); - ep2 = exfat_get_dentry_cached(es, 1); + ep = exfat_get_validated_dentry(es, 0, TYPE_FILE); + ep2 = exfat_get_validated_dentry(es, 1, TYPE_STREAM); ts = current_time(inode); exfat_set_entry_time(sbi, &ts, diff --git a/fs/exfat/inode.c b/fs/exfat/inode.c index f0160a7892a8..e7bc1ee1761a 100644 --- a/fs/exfat/inode.c +++ b/fs/exfat/inode.c @@ -45,8 +45,8 @@ static int __exfat_write_inode(struct inode *inode, int sync) es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES); if (!es) return -EIO; - ep = exfat_get_dentry_cached(es, 0); - ep2 = exfat_get_dentry_cached(es, 1); + ep = exfat_get_validated_dentry(es, 0, TYPE_FILE); + ep2 = exfat_get_validated_dentry(es, 1, TYPE_STREAM); ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode)); @@ -228,7 +228,7 @@ static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset, if (!es) return -EIO; /* get stream entry */ - ep = exfat_get_dentry_cached(es, 1); + ep = exfat_get_validated_dentry(es, 1, TYPE_STREAM); /* update directory entry */ ep->dentry.stream.flags = ei->flags; diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c index 126ed3ba8f47..47fef6b75f28 100644 --- a/fs/exfat/namei.c +++ b/fs/exfat/namei.c @@ -664,8 +664,8 @@ static int exfat_find(struct inode *dir, struct qstr *qname, es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES); if (!es) return -EIO; - ep = exfat_get_dentry_cached(es, 0); - ep2 = exfat_get_dentry_cached(es, 1); + ep = exfat_get_validated_dentry(es, 0, TYPE_FILE); + ep2 = exfat_get_validated_dentry(es, 1, TYPE_STREAM); info->type = exfat_get_entry_type(ep); info->attr = le16_to_cpu(ep->dentry.file.attr);