4.19-stable review patch. If anyone has any objections, please let me know.
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From: Kemeng Shi shikemeng@huaweicloud.com
commit 31f13421c004a420c0e9d288859c9ea9259ea0cc upstream.
Commit 0aeaa2559d6d5 ("ext4: fix corruption when online resizing a 1K bigalloc fs") found that primary superblock's offset in its group is not equal to offset of backup superblock in its group when block size is 1K and bigalloc is enabled. As group descriptor blocks are right after superblock, we can't pass block number of gdb to update_backups for the same reason.
The root casue of the issue above is that leading 1K padding block is count as data block offset for primary block while backup block has no padding block offset in its group.
Remove padding data block count to fix the issue for gdb backups.
For meta_bg case, update_backups treat blk_off as block number, do no conversion in this case.
Signed-off-by: Kemeng Shi shikemeng@huaweicloud.com Reviewed-by: Theodore Ts'o tytso@mit.edu Link: https://lore.kernel.org/r/20230826174712.4059355-2-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o tytso@mit.edu Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ext4/resize.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1565,6 +1565,8 @@ exit_journal: int gdb_num_end = ((group + flex_gd->count - 1) / EXT4_DESC_PER_BLOCK(sb)); int meta_bg = ext4_has_feature_meta_bg(sb); + sector_t padding_blocks = meta_bg ? 0 : sbi->s_sbh->b_blocknr - + ext4_group_first_block_no(sb, 0); sector_t old_gdb = 0;
update_backups(sb, ext4_group_first_block_no(sb, 0), @@ -1576,8 +1578,8 @@ exit_journal: gdb_num); if (old_gdb == gdb_bh->b_blocknr) continue; - update_backups(sb, gdb_bh->b_blocknr, gdb_bh->b_data, - gdb_bh->b_size, meta_bg); + update_backups(sb, gdb_bh->b_blocknr - padding_blocks, + gdb_bh->b_data, gdb_bh->b_size, meta_bg); old_gdb = gdb_bh->b_blocknr; } }