ext4: fix big-endian bugs which could cause fs corruptions
authorZheng Liu <wenqing.lz@taobao.com>
Wed, 3 Apr 2013 16:27:18 +0000 (12:27 -0400)
committerTheodore Ts'o <tytso@mit.edu>
Wed, 3 Apr 2013 16:37:17 +0000 (12:37 -0400)
When an extent was zeroed out, we forgot to do convert from cpu to le16.
It could make us hit a BUG_ON when we try to write dirty pages out.  So
fix it.

[ Also fix a bug found by Dmitry Monakhov where we were missing
  le32_to_cpu() calls in the new indirect punch hole code.

  There are a number of other big endian warnings found by static code
  analyzers, but we'll wait for the next merge window to fix them all
  up.  These fixes are designed to be Obviously Correct by code
  inspection, and easy to demonstrate that it won't make any
  difference (and hence, won't introduce any bugs) on little endian
  architectures such as x86.  --tytso ]

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: CAI Qian <caiqian@redhat.com>
Reported-by: Christian Kujau <lists@nerdbynature.de>
Cc: Dmitry Monakhov <dmonakhov@openvz.org>
fs/ext4/extents.c
fs/ext4/indirect.c

index 56efcaadf8485a5887ae04493b9cacf28b5c73ef..9c6d06dcef8bf1f997c0f05bfe443fcde993d72b 100644 (file)
@@ -2999,20 +2999,23 @@ static int ext4_split_extent_at(handle_t *handle,
                        if (split_flag & EXT4_EXT_DATA_VALID1) {
                                err = ext4_ext_zeroout(inode, ex2);
                                zero_ex.ee_block = ex2->ee_block;
-                               zero_ex.ee_len = ext4_ext_get_actual_len(ex2);
+                               zero_ex.ee_len = cpu_to_le16(
+                                               ext4_ext_get_actual_len(ex2));
                                ext4_ext_store_pblock(&zero_ex,
                                                      ext4_ext_pblock(ex2));
                        } else {
                                err = ext4_ext_zeroout(inode, ex);
                                zero_ex.ee_block = ex->ee_block;
-                               zero_ex.ee_len = ext4_ext_get_actual_len(ex);
+                               zero_ex.ee_len = cpu_to_le16(
+                                               ext4_ext_get_actual_len(ex));
                                ext4_ext_store_pblock(&zero_ex,
                                                      ext4_ext_pblock(ex));
                        }
                } else {
                        err = ext4_ext_zeroout(inode, &orig_ex);
                        zero_ex.ee_block = orig_ex.ee_block;
-                       zero_ex.ee_len = ext4_ext_get_actual_len(&orig_ex);
+                       zero_ex.ee_len = cpu_to_le16(
+                                               ext4_ext_get_actual_len(&orig_ex));
                        ext4_ext_store_pblock(&zero_ex,
                                              ext4_ext_pblock(&orig_ex));
                }
@@ -3272,7 +3275,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
                if (err)
                        goto out;
                zero_ex.ee_block = ex->ee_block;
-               zero_ex.ee_len = ext4_ext_get_actual_len(ex);
+               zero_ex.ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex));
                ext4_ext_store_pblock(&zero_ex, ext4_ext_pblock(ex));
 
                err = ext4_ext_get_access(handle, inode, path + depth);
index b505a145a5937a426184d5c289b6825ee62d0e17..a04183127ef049190ad96c0b7052ea4495fd33e9 100644 (file)
@@ -1539,9 +1539,9 @@ static int free_hole_blocks(handle_t *handle, struct inode *inode,
                blk = *i_data;
                if (level > 0) {
                        ext4_lblk_t first2;
-                       bh = sb_bread(inode->i_sb, blk);
+                       bh = sb_bread(inode->i_sb, le32_to_cpu(blk));
                        if (!bh) {
-                               EXT4_ERROR_INODE_BLOCK(inode, blk,
+                               EXT4_ERROR_INODE_BLOCK(inode, le32_to_cpu(blk),
                                                       "Read failure");
                                return -EIO;
                        }