From 41e5b7ed3e9597ccc46b6affc81872e6370936d9 Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Mon, 8 Jun 2015 11:18:52 -0400 Subject: ext4: verify block bitmap even after fresh initialization If we want to rely on the buffer_verified() flag of the block bitmap buffer, we have to set it consistently. However currently if we're initializing uninitialized block bitmap in ext4_read_block_bitmap_nowait() we're not going to set buffer verified at all. We can do this by simply setting the flag on the buffer, but I think it's actually better to run ext4_validate_block_bitmap() to make sure that what we did in the ext4_init_block_bitmap() is right. So run ext4_validate_block_bitmap() even after the block bitmap initialization. Also bail out early from ext4_validate_block_bitmap() if we see corrupt bitmap, since we already know it's corrupt and we do not need to verify that. Signed-off-by: Lukas Czerner Signed-off-by: Theodore Ts'o diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 955bf49..cd6ea29 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -369,7 +369,7 @@ static void ext4_validate_block_bitmap(struct super_block *sb, struct ext4_group_info *grp = ext4_get_group_info(sb, block_group); struct ext4_sb_info *sbi = EXT4_SB(sb); - if (buffer_verified(bh)) + if (buffer_verified(bh) || EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) return; ext4_lock_group(sb, block_group); @@ -446,7 +446,7 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) unlock_buffer(bh); if (err) ext4_error(sb, "Checksum bad for grp %u", block_group); - return bh; + goto verify; } ext4_unlock_group(sb, block_group); if (buffer_uptodate(bh)) { -- cgit v0.10.2