From: Tao Ma Subject: [PATCH V5 09/23] ext4: Refactor __ext4_check_dir_entry to accepts start and size. Date: Sat, 30 Jun 2012 23:45:10 +0800 Message-ID: <1341071124-4976-9-git-send-email-tm@tao.ma> References: <1341070917-4889-1-git-send-email-tm@tao.ma> <1341071124-4976-1-git-send-email-tm@tao.ma> To: linux-ext4@vger.kernel.org Return-path: Received: from oproxy5-pub.bluehost.com ([67.222.38.55]:35542 "HELO oproxy5-pub.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755427Ab2F3PsB (ORCPT ); Sat, 30 Jun 2012 11:48:01 -0400 Received: from [221.217.40.18] (port=40170 helo=localhost.localdomain) by box585.bluehost.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.76) (envelope-from ) id 1Skztw-0006eg-2T for linux-ext4@vger.kernel.org; Sat, 30 Jun 2012 09:48:00 -0600 In-Reply-To: <1341071124-4976-1-git-send-email-tm@tao.ma> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Tao Ma __ext4_check_dir_entry is used to check whether the de is over the block boundary. Now with inline data, it could be within the block boundary while exceeds the inode size. So check this function to check the overflow more precisely. Signed-off-by: Tao Ma --- fs/ext4/dir.c | 16 ++++++++-------- fs/ext4/ext4.h | 7 ++++--- fs/ext4/namei.c | 13 +++++++++---- 3 files changed, 21 insertions(+), 15 deletions(-) diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index aa39e60..1b2afca 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -72,7 +72,7 @@ static int is_dx_dir(struct inode *inode) int __ext4_check_dir_entry(const char *function, unsigned int line, struct inode *dir, struct file *filp, struct ext4_dir_entry_2 *de, - struct buffer_head *bh, + struct buffer_head *bh, char *buf, int size, unsigned int offset) { const char *error_msg = NULL; @@ -85,9 +85,8 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, error_msg = "rec_len % 4 != 0"; else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len))) error_msg = "rec_len is too small for name_len"; - else if (unlikely(((char *) de - bh->b_data) + rlen > - dir->i_sb->s_blocksize)) - error_msg = "directory entry across blocks"; + else if (unlikely(((char *) de - buf) + rlen > size)) + error_msg = "directory entry across range"; else if (unlikely(le32_to_cpu(de->inode) > le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count))) error_msg = "inode out of bounds"; @@ -98,14 +97,14 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, ext4_error_file(filp, function, line, bh->b_blocknr, "bad entry in directory: %s - offset=%u(%u), " "inode=%u, rec_len=%d, name_len=%d", - error_msg, (unsigned) (offset % bh->b_size), + error_msg, (unsigned) (offset % size), offset, le32_to_cpu(de->inode), rlen, de->name_len); else ext4_error_inode(dir, function, line, bh->b_blocknr, "bad entry in directory: %s - offset=%u(%u), " "inode=%u, rec_len=%d, name_len=%d", - error_msg, (unsigned) (offset % bh->b_size), + error_msg, (unsigned) (offset % size), offset, le32_to_cpu(de->inode), rlen, de->name_len); @@ -221,8 +220,9 @@ revalidate: while (!error && filp->f_pos < inode->i_size && offset < sb->s_blocksize) { de = (struct ext4_dir_entry_2 *) (bh->b_data + offset); - if (ext4_check_dir_entry(inode, filp, de, - bh, offset)) { + if (ext4_check_dir_entry(inode, filp, de, bh, + bh->b_data, bh->b_size, + offset)) { /* * On error, skip the f_pos to the next block */ diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 7edcd79..5e94632 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1922,10 +1922,11 @@ ext4_fsblk_t ext4_inode_to_goal_block(struct inode *); extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *, struct file *, struct ext4_dir_entry_2 *, - struct buffer_head *, unsigned int); -#define ext4_check_dir_entry(dir, filp, de, bh, offset) \ + struct buffer_head *, char *, int, + unsigned int); +#define ext4_check_dir_entry(dir, filp, de, bh, buf, size, offset) \ unlikely(__ext4_check_dir_entry(__func__, __LINE__, (dir), (filp), \ - (de), (bh), (offset))) + (de), (bh), (buf), (size), (offset))) extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash, __u32 minor_hash, struct ext4_dir_entry_2 *dirent); diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 84f0c78..407e8ca 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -857,6 +857,7 @@ static int htree_dirblock_to_tree(struct file *dir_file, EXT4_DIR_REC_LEN(0)); for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { if (ext4_check_dir_entry(dir, NULL, de, bh, + bh->b_data, bh->b_size, (block<i_sb)) + ((char *)de - bh->b_data))) { /* On error, skip the f_pos to the next block. */ @@ -1095,7 +1096,8 @@ static inline int search_dirblock(struct buffer_head *bh, if ((char *) de + namelen <= dlimit && ext4_match (namelen, name, de)) { /* found a match - just to be sure, do a full check */ - if (ext4_check_dir_entry(dir, NULL, de, bh, offset)) + if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, + bh->b_size, offset)) return -1; *res_dir = de; return 1; @@ -1584,7 +1586,8 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, de = (struct ext4_dir_entry_2 *)bh->b_data; top = bh->b_data + (blocksize - csum_size) - reclen; while ((char *) de <= top) { - if (ext4_check_dir_entry(dir, NULL, de, bh, offset)) + if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, + bh->b_size, offset)) return -EIO; if (ext4_match(namelen, name, de)) return -EEXIST; @@ -2004,7 +2007,8 @@ static int ext4_delete_entry(handle_t *handle, pde = NULL; de = (struct ext4_dir_entry_2 *) bh->b_data; while (i < bh->b_size - csum_size) { - if (ext4_check_dir_entry(dir, NULL, de, bh, i)) + if (ext4_check_dir_entry(dir, NULL, de, bh, + bh->b_data, bh->b_size, i)) return -EIO; if (de == de_del) { BUFFER_TRACE(bh, "get_write_access"); @@ -2349,7 +2353,8 @@ static int empty_dir(struct inode *inode) set_buffer_verified(bh); de = (struct ext4_dir_entry_2 *) bh->b_data; } - if (ext4_check_dir_entry(inode, NULL, de, bh, offset)) { + if (ext4_check_dir_entry(inode, NULL, de, bh, + bh->b_data, bh->b_size, offset)) { de = (struct ext4_dir_entry_2 *)(bh->b_data + sb->s_blocksize); offset = (offset | (sb->s_blocksize - 1)) + 1; -- 1.7.0.4