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Subject: #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git fd57572253bc356330dbe5b233c2e1d8426c66fd
Author: dmantipov@yandex.ru

diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index fcc89856ab95..1b6bdd9d7755 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -1503,6 +1503,23 @@ int ocfs2_validate_inode_block(struct super_block *sb,
 		goto bail;
 	}
 
+	if (le32_to_cpu(di->i_flags) & OCFS2_CHAIN_FL) {
+		struct ocfs2_chain_list *cl = &di->id2.i_chain;
+
+		if (le16_to_cpu(cl->cl_count) != ocfs2_chain_recs_per_inode(sb)) {
+			rc = ocfs2_error(sb, "Invalid dinode %llu: chain list count %u\n",
+					 (unsigned long long)bh->b_blocknr,
+					 le16_to_cpu(cl->cl_count));
+			goto bail;
+		}
+		if (le16_to_cpu(cl->cl_next_free_rec) > le16_to_cpu(cl->cl_count)) {
+			rc = ocfs2_error(sb, "Invalid dinode %llu: chain list index %u\n",
+					 (unsigned long long)bh->b_blocknr,
+					 le16_to_cpu(cl->cl_next_free_rec));
+			goto bail;
+		}
+	}
+
 	rc = 0;
 
 bail: