Re: [syzbot] [ocfs2?] kernel BUG in ocfs2_remove_btree_range (2)

[Edward Adam Davis]

#syz test

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 162711cc5b20..570d747a00ca 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -6164,7 +6164,7 @@ static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb,
 	struct buffer_head *bh = NULL;
 	struct ocfs2_dinode *di;
 	struct ocfs2_truncate_log *tl;
-	unsigned int tl_count;
+	unsigned int tl_count, tl_used;
 
 	inode = ocfs2_get_system_file_inode(osb,
 					   TRUNCATE_LOG_SYSTEM_INODE,
@@ -6185,8 +6185,10 @@ static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb,
 	di = (struct ocfs2_dinode *)bh->b_data;
 	tl = &di->id2.i_dealloc;
 	tl_count = le16_to_cpu(tl->tl_count);
+	tl_used = le16_to_cpu(tl->tl_used);
 	if (unlikely(tl_count > ocfs2_truncate_recs_per_inode(osb->sb) ||
-		     tl_count == 0)) {
+		     tl_count == 0) ||
+		     tl_used > tl_count) {
 		status = -EFSCORRUPTED;
 		iput(inode);
 		brelse(bh);