1 files changed, 12 insertions, 2 deletions

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index f525f909b559..fb83750c1a14 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -150,7 +150,16 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
         }
 
         ext4_lock_group(sb, block_group);
-        if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
+        if (ext4_has_group_desc_csum(sb) &&
+            (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT))) {
+                if (block_group == 0) {
+                        ext4_unlock_group(sb, block_group);
+                        unlock_buffer(bh);
+                        ext4_error(sb, "Inode bitmap for bg 0 marked "
+                                   "uninitialized");
+                        err = -EFSCORRUPTED;
+                        goto out;
+                }
                 memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
                 ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb),
                                      sb->s_blocksize * 8, bh->b_data);
@@ -994,7 +1003,8 @@ got:
 
                 /* recheck and clear flag under lock if we still need to */
                 ext4_lock_group(sb, group);
-                if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
+                if (ext4_has_group_desc_csum(sb) &&
+                    (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {
                         gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
                         ext4_free_group_clusters_set(sb, gdp,
                                 ext4_free_clusters_after_init(sb, group, gdp));