path: root/fs
diff options
authorMaarten ter Huurne <>2013-07-01 08:12:08 -0400
committerGreg Kroah-Hartman <>2013-07-21 18:21:23 -0700
commitb6a81140efa3b994f3bde4ea48434cfc6e5d4fe9 (patch)
treee3a2116ad5df6124662a3f15bf15c2d4c4fa5fa4 /fs
parent15f26a4c4820d1fb5f1ba979b4fe4d00a2d38b7d (diff)
ext4: fix corruption when online resizing a fs with 1K block size
commit 6ca792edc13c409e8d4eb9001e048264c6a2eb64 upstream. Subtracting the number of the first data block places the superblock backups one block too early, corrupting the file system. When the block size is larger than 1K, the first data block is 0, so the subtraction has no effect and no corruption occurs. Signed-off-by: Maarten ter Huurne <> Signed-off-by: "Theodore Ts'o" <> Reviewed-by: Jan Kara <> Signed-off-by: Greg Kroah-Hartman <>
Diffstat (limited to 'fs')
1 files changed, 1 insertions, 3 deletions
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index b27c96d01965..49d3c01eabf8 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -1656,12 +1656,10 @@ errout:
err = err2;
if (!err) {
- ext4_fsblk_t first_block;
- first_block = ext4_group_first_block_no(sb, 0);
if (test_opt(sb, DEBUG))
printk(KERN_DEBUG "EXT4-fs: extended group to %llu "
"blocks\n", ext4_blocks_count(es));
- update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr - first_block,
+ update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr,
(char *)es, sizeof(struct ext4_super_block), 0);
return err;