From: Akira Fujita Subject: [PATCH 1/3] ext4: Fix insertion point of extent in mext_insert_across_blocks() Date: Wed, 03 Mar 2010 15:49:29 +0900 Message-ID: <4B8E0679.8060706@rs.jp.nec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: ext4 development To: Theodore Tso Return-path: Received: from TYO202.gate.nec.co.jp ([202.32.8.206]:57149 "EHLO tyo202.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754542Ab0CCGuc (ORCPT ); Wed, 3 Mar 2010 01:50:32 -0500 Sender: linux-ext4-owner@vger.kernel.org List-ID: ext4: Fix insertion point of extent in mext_insert_across_blocks() From: Akira Fujita If the leaf node has 2 extent space or fewer and EXT4_IOC_MOVE_EXT ioctl is called with the file offset where after the 2nd extent covers, mext_insert_across_blocks() always tries to insert extent into the first extent. As a result, the file gets corrupted because of wrong extent order. The patch fixes this problem. Signed-off-by: Akira Fujita --- fs/ext4/move_extent.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index 1654eb8..9eca1c0 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -252,6 +252,7 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode, } o_start->ee_len = start_ext->ee_len; + eblock = le32_to_cpu(start_ext->ee_block); new_flag = 1; } else if (start_ext->ee_len && new_ext->ee_len && @@ -262,6 +263,7 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode, * orig |------------------------------| */ o_start->ee_len = start_ext->ee_len; + eblock = le32_to_cpu(start_ext->ee_block); new_flag = 1; } else if (!start_ext->ee_len && new_ext->ee_len && @@ -502,6 +504,7 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, le32_to_cpu(oext->ee_block) + oext_alen) { start_ext.ee_len = cpu_to_le16(le32_to_cpu(new_ext.ee_block) - le32_to_cpu(oext->ee_block)); + start_ext.ee_block = oext->ee_block; copy_extent_status(oext, &start_ext); } else if (oext > EXT_FIRST_EXTENT(orig_path[depth].p_hdr)) { prev_ext = oext - 1; @@ -515,6 +518,7 @@ mext_leaf_block(handle_t *handle, struct inode *orig_inode, start_ext.ee_len = cpu_to_le16( ext4_ext_get_actual_len(prev_ext) + new_ext_alen); + start_ext.ee_block = oext->ee_block; copy_extent_status(prev_ext, &start_ext); new_ext.ee_len = 0; }