[PATCH 2/3] fs/ntfs3: Reject mount if boot's cluster size < media sector size

[Konstantin Komarov]

If we continue to work in this case, then we can corrupt fs.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
---
 fs/ntfs3/super.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index 7099d9b1f3aa..193f9a98f6ab 100644
--- a/fs/ntfs3/super.c
+++ b/fs/ntfs3/super.c
@@ -763,9 +763,14 @@ static int ntfs_init_from_boot(struct super_block *sb, u32 sector_size,
 	sbi->mft.lbo = mlcn << sbi->cluster_bits;
 	sbi->mft.lbo2 = mlcn2 << sbi->cluster_bits;
 
+	/* Compare boot's cluster and sector. */
 	if (sbi->cluster_size < sbi->sector_size)
 		goto out;
 
+	/* Compare boot's cluster and media sector. */
+	if (sbi->cluster_size < sector_size)
+		goto out; /* No way to use ntfs_get_block in this case. */
+
 	sbi->cluster_mask = sbi->cluster_size - 1;
 	sbi->cluster_mask_inv = ~(u64)sbi->cluster_mask;
 	sbi->record_size = record_size = boot->record_size < 0
-- 
2.33.0