1 ext4: fix online resize with a non-standard blocks per group setting
3 The set_flexbg_block_bitmap() function assumed that the number of
4 blocks in a blockgroup was sb->blocksize * 8, which is normally true,
5 but not always! Use EXT4_BLOCKS_PER_GROUP(sb) instead, to fix block
6 bitmap corruption after:
8 mke2fs -t ext4 -g 3072 -i 4096 /dev/vdd 1G
9 mount -t ext4 /dev/vdd /vdd
12 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
13 Reported-by: Jon Bernard <jbernard@tuxion.com>
14 Cc: stable@vger.kernel.org
16 fs/ext4/resize.c | 2 +-
17 1 file changed, 1 insertion(+), 1 deletion(-)
19 diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
20 index 69a6261..f3b84cd 100644
21 --- a/fs/ext4/resize.c
22 +++ b/fs/ext4/resize.c
23 @@ -409,7 +409,7 @@ static int set_flexbg_block_bitmap(struct super_block *sb, handle_t *handle,
24 start = ext4_group_first_block_no(sb, group);
25 group -= flex_gd->groups[0].group;
27 - count2 = sb->s_blocksize * 8 - (block - start);
28 + count2 = EXT4_BLOCKS_PER_GROUP(sb) - (block - start);