[v2] exfat: handle unreconized benign secondary entries

Message ID	20230112140509.11525-1-linkinjeon@kernel.org (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-fsdevel-owner@vger.kernel.org> From: Namjae Jeon <linkinjeon@kernel.org> To: linux-fsdevel@vger.kernel.org Cc: Namjae Jeon <linkinjeon@kernel.org>, Yuezhang Mo <Yuezhang.Mo@sony.com>, Wang Yugui <wangyugui@e16-tech.com>, =?utf-8?b?QmFyw7Njc2kgRMOpbmVz?= <admin@tveger.hu>, Sungjong Seo <sj1557.seo@samsung.com> Subject: [PATCH v2] exfat: handle unreconized benign secondary entries Date: Thu, 12 Jan 2023 23:05:09 +0900 Message-Id: <20230112140509.11525-1-linkinjeon@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	[v2] exfat: handle unreconized benign secondary entries \| expand [v2] exfat: handle unreconized benign secondary entries

diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index 158427e8124e..63c2f09ff93a 100644 --- a/fs/exfat/dir.c +++ b/fs/exfat/dir.c @@ -29,14 +29,15 @@ static int exfat_extract_uni_name(struct exfat_dentry *ep, } -static void exfat_get_uniname_from_ext_entry(struct super_block *sb, +static int exfat_get_uniname_from_ext_entry(struct super_block *sb, struct exfat_chain *p_dir, int entry, unsigned short *uniname) { - int i; + int i, err; struct exfat_entry_set_cache es; - if (exfat_get_dentry_set(&es, sb, p_dir, entry, ES_ALL_ENTRIES)) - return; + err = exfat_get_dentry_set(&es, sb, p_dir, entry, ES_ALL_ENTRIES); + if (err) + return err; /* * First entry : file entry @@ -56,12 +57,13 @@ static void exfat_get_uniname_from_ext_entry(struct super_block *sb, } exfat_put_dentry_set(&es, false); + return 0; } /* read a directory entry from the opened directory */ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_entry *dir_entry) { - int i, dentries_per_clu, num_ext; + int i, dentries_per_clu, num_ext, err; unsigned int type, clu_offset, max_dentries; struct exfat_chain dir, clu; struct exfat_uni_name uni_name; @@ -146,8 +148,12 @@ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_ent 0); *uni_name.name = 0x0; - exfat_get_uniname_from_ext_entry(sb, &clu, i, + err = exfat_get_uniname_from_ext_entry(sb, &clu, i, uni_name.name); + if (err) { + brelse(bh); + continue; + } exfat_utf16_to_nls(sb, &uni_name, dir_entry->namebuf.lfn, dir_entry->namebuf.lfnbuf_len); @@ -375,6 +381,12 @@ unsigned int exfat_get_entry_type(struct exfat_dentry *ep) return TYPE_ACL; return TYPE_CRITICAL_SEC; } + + if (ep->type == EXFAT_VENDOR_EXT) + return TYPE_VENDOR_EXT; + if (ep->type == EXFAT_VENDOR_ALLOC) + return TYPE_VENDOR_ALLOC; + return TYPE_BENIGN_SEC; } @@ -518,6 +530,25 @@ int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir, return ret; } +static void exfat_free_benign_secondary_clusters(struct inode *inode, + struct exfat_dentry *ep) +{ + struct super_block *sb = inode->i_sb; + struct exfat_chain dir; + unsigned int start_clu = + le32_to_cpu(ep->dentry.generic_secondary.start_clu); + u64 size = le64_to_cpu(ep->dentry.generic_secondary.size); + unsigned char flags = ep->dentry.generic_secondary.flags; + + if (!(flags & ALLOC_FAT_CHAIN) || !start_clu || !size) + return; + + exfat_chain_set(&dir, start_clu, + EXFAT_B_TO_CLU_ROUND_UP(size, EXFAT_SB(sb)), + flags); + exfat_free_cluster(inode, &dir); +} + int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir, int entry, int num_entries, struct exfat_uni_name *p_uniname) { @@ -550,6 +581,9 @@ int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir, if (!ep) return -EIO; + if (exfat_get_entry_type(ep) & TYPE_BENIGN_SEC) + exfat_free_benign_secondary_clusters(inode, ep); + exfat_init_name_entry(ep, uniname); exfat_update_bh(bh, sync); brelse(bh); @@ -573,6 +607,9 @@ int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir, if (!ep) return -EIO; + if (exfat_get_entry_type(ep) & TYPE_BENIGN_SEC) + exfat_free_benign_secondary_clusters(inode, ep); + exfat_set_entry_type(ep, TYPE_DELETED); exfat_update_bh(bh, IS_DIRSYNC(inode)); brelse(bh); @@ -741,6 +778,7 @@ enum exfat_validate_dentry_mode { ES_MODE_GET_STRM_ENTRY, ES_MODE_GET_NAME_ENTRY, ES_MODE_GET_CRITICAL_SEC_ENTRY, + ES_MODE_GET_BENIGN_SEC_ENTRY, }; static bool exfat_validate_entry(unsigned int type, @@ -754,36 +792,33 @@ static bool exfat_validate_entry(unsigned int type, if (type != TYPE_FILE && type != TYPE_DIR) return false; *mode = ES_MODE_GET_FILE_ENTRY; - return true; + break; case ES_MODE_GET_FILE_ENTRY: if (type != TYPE_STREAM) return false; *mode = ES_MODE_GET_STRM_ENTRY; - return true; + break; case ES_MODE_GET_STRM_ENTRY: if (type != TYPE_EXTEND) return false; *mode = ES_MODE_GET_NAME_ENTRY; - return true; + break; case ES_MODE_GET_NAME_ENTRY: - if (type == TYPE_STREAM) + if (type & TYPE_BENIGN_SEC) + *mode = ES_MODE_GET_BENIGN_SEC_ENTRY; + else if (type != TYPE_EXTEND) 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) + break; + case ES_MODE_GET_BENIGN_SEC_ENTRY: + /* Assume unreconized benign secondary entry */ + if (!(type & TYPE_BENIGN_SEC)) return false; - return true; + break; default: - WARN_ON_ONCE(1); return false; } + + return true; } struct exfat_dentry *exfat_get_dentry_cached( @@ -1164,10 +1199,8 @@ 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_CRITICAL_SEC || type & TYPE_BENIGN_SEC) count++; - else - break; } return count; } diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h index 25a5df0fdfe0..8a399e234aab 100644 --- a/fs/exfat/exfat_fs.h +++ b/fs/exfat/exfat_fs.h @@ -71,6 +71,8 @@ enum { #define TYPE_PADDING 0x0402 #define TYPE_ACLTAB 0x0403 #define TYPE_BENIGN_SEC 0x0800 +#define TYPE_VENDOR_EXT 0x0801 +#define TYPE_VENDOR_ALLOC 0x0802 #define MAX_CHARSET_SIZE 6 /* max size of multi-byte character */ #define MAX_NAME_LENGTH 255 /* max len of file name excluding NULL */ diff --git a/fs/exfat/exfat_raw.h b/fs/exfat/exfat_raw.h index 7f39b1c6469c..066df432f38e 100644 --- a/fs/exfat/exfat_raw.h +++ b/fs/exfat/exfat_raw.h @@ -50,6 +50,8 @@ #define EXFAT_STREAM 0xC0 /* stream entry */ #define EXFAT_NAME 0xC1 /* file name entry */ #define EXFAT_ACL 0xC2 /* stream entry */ +#define EXFAT_VENDOR_EXT 0xE0 /* vendor extension entry */ +#define EXFAT_VENDOR_ALLOC 0xE1 /* vendor allocation entry */ #define IS_EXFAT_CRITICAL_PRI(x) (x < 0xA0) #define IS_EXFAT_BENIGN_PRI(x) (x < 0xC0) @@ -155,6 +157,24 @@ struct exfat_dentry { __le32 start_clu; __le64 size; } __packed upcase; /* up-case table directory entry */ + struct { + __u8 flags; + __u8 vendor_guid[16]; + __u8 vendor_defined[14]; + } __packed vendor_ext; /* vendor extension directory entry */ + struct { + __u8 flags; + __u8 vendor_guid[16]; + __u8 vendor_defined[2]; + __le32 start_clu; + __le64 size; + } __packed vendor_alloc; /* vendor allocation directory entry */ + struct { + __u8 flags; + __u8 custom_defined[18]; + __le32 start_clu; + __le64 size; + } __packed generic_secondary; /* generic secondary directory entry */ } __packed dentry; } __packed;

[v2] exfat: handle unreconized benign secondary entries

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