From: Gabriel Krisman Bertazi Subject: [PATCH RFC v2 12/13] ext4: Support charset name matching Date: Thu, 25 Jan 2018 00:53:48 -0200 Message-ID: <20180125025349.31494-13-krisman@collabora.co.uk> References: <20180125025349.31494-1-krisman@collabora.co.uk> Cc: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, alvaro.soliverez@collabora.co.uk, kernel@lists.collabora.co.uk, Gabriel Krisman Bertazi To: tytso@mit.edu, david@fromorbit.com, olaf@sgi.com, viro@zeniv.linux.org.uk Return-path: Received: from bhuna.collabora.co.uk ([46.235.227.227]:52126 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933065AbeAYCze (ORCPT ); Wed, 24 Jan 2018 21:55:34 -0500 In-Reply-To: <20180125025349.31494-1-krisman@collabora.co.uk> Sender: linux-ext4-owner@vger.kernel.org List-ID: Implement generic caseless lookup based on the mount flags using the charset library. Signed-off-by: Gabriel Krisman Bertazi --- fs/ext4/namei.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index e750d68fbcb5..24056172e225 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1255,8 +1255,10 @@ static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) * * Return: %true if the directory entry matches, otherwise %false. */ -static inline bool ext4_match(const struct ext4_filename *fname, - const struct ext4_dir_entry_2 *de) +static inline bool ext4_match(const struct charset *charset, + const struct ext4_filename *fname, + const struct ext4_dir_entry_2 *de, + bool ignorecase) { struct fscrypt_name f; @@ -1268,7 +1270,8 @@ static inline bool ext4_match(const struct ext4_filename *fname, #ifdef CONFIG_EXT4_FS_ENCRYPTION f.crypto_buf = fname->crypto_buf; #endif - return fscrypt_match_name(&f, de->name, de->name_len); + return fscrypt_charset_match_name(&f, charset, de->name, de->name_len, + ignorecase); } /* @@ -1281,6 +1284,8 @@ int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, struct ext4_dir_entry_2 * de; char * dlimit; int de_len; + struct super_block *sb = dir->i_sb; + bool ignorecase = test_opt2(sb, CASE_INSENSITIVE); de = (struct ext4_dir_entry_2 *)search_buf; dlimit = search_buf + buf_size; @@ -1288,7 +1293,7 @@ int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, /* this code is executed quadratically often */ /* do minimal checking `by hand' */ if ((char *) de + de->name_len <= dlimit && - ext4_match(fname, de)) { + ext4_match(EXT4_SB(sb)->encoding, fname, de, ignorecase)) { /* found a match - just to be sure, do * a full check */ if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, @@ -1389,11 +1394,13 @@ static struct buffer_head * ext4_find_entry (struct inode *dir, if (is_dx(dir)) { ret = ext4_dx_find_entry(dir, &fname, res_dir); /* - * On success, or if the error was file not found, - * return. Otherwise, fall back to doing a search the - * old fashioned way. + * On success, or if the file cannot be found, return. + * If an error occurred, or if the file was not found + * but we can do case-insensitive lookups, fall back to + * the linear search. */ - if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) + if ((!IS_ERR(ret) && (ret || !test_opt2(sb, CASE_INSENSITIVE))) || + (IS_ERR(ret) && PTR_ERR(ret) != ERR_BAD_DX_DIR)) goto cleanup_and_exit; dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " "falling back\n")); @@ -1788,6 +1795,8 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode, int nlen, rlen; unsigned int offset = 0; char *top; + struct super_block *sb = dir->i_sb; + bool ignorecase = test_opt2(sb, CASE_INSENSITIVE); de = (struct ext4_dir_entry_2 *)buf; top = buf + buf_size - reclen; @@ -1795,7 +1804,7 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode, if (ext4_check_dir_entry(dir, NULL, de, bh, buf, buf_size, offset)) return -EFSCORRUPTED; - if (ext4_match(fname, de)) + if (ext4_match(EXT4_SB(sb)->encoding, fname, de, ignorecase)) return -EEXIST; nlen = EXT4_DIR_REC_LEN(de->name_len); rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); -- 2.15.1