| From 3d2660d0c9c2f296837078c189b68a47f6b2e3b5 Mon Sep 17 00:00:00 2001 |
| From: Theodore Ts'o <tytso@mit.edu> |
| Date: Sat, 15 Feb 2014 22:42:25 -0500 |
| Subject: ext4: fix online resize with a non-standard blocks per group setting |
| |
| From: Theodore Ts'o <tytso@mit.edu> |
| |
| commit 3d2660d0c9c2f296837078c189b68a47f6b2e3b5 upstream. |
| |
| The set_flexbg_block_bitmap() function assumed that the number of |
| blocks in a blockgroup was sb->blocksize * 8, which is normally true, |
| but not always! Use EXT4_BLOCKS_PER_GROUP(sb) instead, to fix block |
| bitmap corruption after: |
| |
| mke2fs -t ext4 -g 3072 -i 4096 /dev/vdd 1G |
| mount -t ext4 /dev/vdd /vdd |
| resize2fs /dev/vdd 8G |
| |
| Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> |
| Reported-by: Jon Bernard <jbernard@tuxion.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| fs/ext4/resize.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/fs/ext4/resize.c |
| +++ b/fs/ext4/resize.c |
| @@ -409,7 +409,7 @@ static int set_flexbg_block_bitmap(struc |
| start = ext4_group_first_block_no(sb, group); |
| group -= flex_gd->groups[0].group; |
| |
| - count2 = sb->s_blocksize * 8 - (block - start); |
| + count2 = EXT4_BLOCKS_PER_GROUP(sb) - (block - start); |
| if (count2 > count) |
| count2 = count; |
| |
