1 files changed, 16 insertions, 8 deletions

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index b00481c475cb..aa52d87985aa 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -184,7 +184,6 @@ static int ext4_init_block_bitmap(struct super_block *sb,
 	unsigned int bit, bit_max;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	ext4_fsblk_t start, tmp;
-	int flex_bg = 0;
 
 	J_ASSERT_BH(bh, buffer_locked(bh));
 
@@ -207,22 +206,19 @@ static int ext4_init_block_bitmap(struct super_block *sb,
 
 	start = ext4_group_first_block_no(sb, block_group);
 
-	if (ext4_has_feature_flex_bg(sb))
-		flex_bg = 1;
-
 	/* Set bits for block and inode bitmaps, and inode table */
 	tmp = ext4_block_bitmap(sb, gdp);
-	if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
+	if (ext4_block_in_group(sb, tmp, block_group))
 		ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
 
 	tmp = ext4_inode_bitmap(sb, gdp);
-	if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
+	if (ext4_block_in_group(sb, tmp, block_group))
 		ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
 
 	tmp = ext4_inode_table(sb, gdp);
 	for (; tmp < ext4_inode_table(sb, gdp) +
 		     sbi->s_itb_per_group; tmp++) {
-		if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
+		if (ext4_block_in_group(sb, tmp, block_group))
 			ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
 	}
 
@@ -372,6 +368,8 @@ static int ext4_validate_block_bitmap(struct super_block *sb,
 		return -EFSCORRUPTED;
 
 	ext4_lock_group(sb, block_group);
+	if (buffer_verified(bh))
+		goto verified;
 	if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group,
 			desc, bh))) {
 		ext4_unlock_group(sb, block_group);
@@ -390,6 +388,7 @@ static int ext4_validate_block_bitmap(struct super_block *sb,
 		return -EFSCORRUPTED;
 	}
 	set_buffer_verified(bh);
+verified:
 	ext4_unlock_group(sb, block_group);
 	return 0;
 }
@@ -442,7 +441,16 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
 		goto verify;
 	}
 	ext4_lock_group(sb, block_group);
-	if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
+	if (ext4_has_group_desc_csum(sb) &&
+	    (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {
+		if (block_group == 0) {
+			ext4_unlock_group(sb, block_group);
+			unlock_buffer(bh);
+			ext4_error(sb, "Block bitmap for bg 0 marked "
+				   "uninitialized");
+			err = -EFSCORRUPTED;
+			goto out;
+		}
 		err = ext4_init_block_bitmap(sb, bh, block_group, desc);
 		set_bitmap_uptodate(bh);
 		set_buffer_uptodate(bh);