From 40da553f5da020931e9cddf02948847a188c5223 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 19 Feb 2024 18:10:33 +0100 Subject: ext4: verify s_clusters_per_group even without bigalloc Currently we ignore s_clusters_per_group field in the on-disk superblock if bigalloc feature is not enabled. However e2fsprogs don't even open the filesystem if s_clusters_per_group is invalid. This results in an odd state where kernel happily works with the filesystem while even e2fsck refuses to touch it. Verify that s_clusters_per_group is valid even if bigalloc feature is not enabled to make things consistent. Due to current e2fsprogs behavior it is unlikely there are filesystems out in the wild (except for intentionally fuzzed ones) with invalid s_clusters_per_group counts. Signed-off-by: Jan Kara Reviewed-by: Zhang Yi Link: https://lore.kernel.org/r/20240219171033.22882-1-jack@suse.cz Signed-off-by: Theodore Ts'o --- fs/ext4/super.c | 30 +++++++++++++----------------- 1 file changed, 13 insertions(+), 17 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 3f595090eb62..91e9f961993d 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4422,22 +4422,6 @@ static int ext4_handle_clustersize(struct super_block *sb) } sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) - le32_to_cpu(es->s_log_block_size); - sbi->s_clusters_per_group = - le32_to_cpu(es->s_clusters_per_group); - if (sbi->s_clusters_per_group > sb->s_blocksize * 8) { - ext4_msg(sb, KERN_ERR, - "#clusters per group too big: %lu", - sbi->s_clusters_per_group); - return -EINVAL; - } - if (sbi->s_blocks_per_group != - (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) { - ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and " - "clusters per group (%lu) inconsistent", - sbi->s_blocks_per_group, - sbi->s_clusters_per_group); - return -EINVAL; - } } else { if (clustersize != sb->s_blocksize) { ext4_msg(sb, KERN_ERR, @@ -4451,9 +4435,21 @@ static int ext4_handle_clustersize(struct super_block *sb) sbi->s_blocks_per_group); return -EINVAL; } - sbi->s_clusters_per_group = sbi->s_blocks_per_group; sbi->s_cluster_bits = 0; } + sbi->s_clusters_per_group = le32_to_cpu(es->s_clusters_per_group); + if (sbi->s_clusters_per_group > sb->s_blocksize * 8) { + ext4_msg(sb, KERN_ERR, "#clusters per group too big: %lu", + sbi->s_clusters_per_group); + return -EINVAL; + } + if (sbi->s_blocks_per_group != + (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) { + ext4_msg(sb, KERN_ERR, + "blocks per group (%lu) and clusters per group (%lu) inconsistent", + sbi->s_blocks_per_group, sbi->s_clusters_per_group); + return -EINVAL; + } sbi->s_cluster_ratio = clustersize / sb->s_blocksize; /* Do we have standard group size of clustersize * 8 blocks ? */ -- cgit v1.2.3