ext4: avoid dividing by 0 in mb_update_avg_fragment_size() when block bitmap corrupt
Determine if bb_fragments is 0 instead of determining bb_free to eliminate
the risk of dividing by zero when the block bitmap is corrupted.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240104142040.2835097-6-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index fa351aa..751e31d 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -842,7 +842,7 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp)
struct ext4_sb_info *sbi = EXT4_SB(sb);
int new_order;
- if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_free == 0)
+ if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_fragments == 0)
return;
new_order = mb_avg_fragment_size_order(sb,
