1 files changed, 28 insertions, 10 deletions

diff --git a/fs/nilfs2/dat.c b/fs/nilfs2/dat.c
index 9930fa901039..9cf6ba58f585 100644
--- a/fs/nilfs2/dat.c
+++ b/fs/nilfs2/dat.c
@@ -40,8 +40,21 @@ static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
 static int nilfs_dat_prepare_entry(struct inode *dat,
 				   struct nilfs_palloc_req *req, int create)
 {
-	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
-					    create, &req->pr_entry_bh);
+	int ret;
+
+	ret = nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
+					   create, &req->pr_entry_bh);
+	if (unlikely(ret == -ENOENT)) {
+		nilfs_err(dat->i_sb,
+			  "DAT doesn't have a block to manage vblocknr = %llu",
+			  (unsigned long long)req->pr_entry_nr);
+		/*
+		 * Return internal code -EINVAL to notify bmap layer of
+		 * metadata corruption.
+		 */
+		ret = -EINVAL;
+	}
+	return ret;
 }
 
 static void nilfs_dat_commit_entry(struct inode *dat,
@@ -123,11 +136,7 @@ static void nilfs_dat_commit_free(struct inode *dat,
 
 int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
 {
-	int ret;
-
-	ret = nilfs_dat_prepare_entry(dat, req, 0);
-	WARN_ON(ret == -ENOENT);
-	return ret;
+	return nilfs_dat_prepare_entry(dat, req, 0);
 }
 
 void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
@@ -149,19 +158,19 @@ void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
 int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
 {
 	struct nilfs_dat_entry *entry;
+	__u64 start;
 	sector_t blocknr;
 	void *kaddr;
 	int ret;
 
 	ret = nilfs_dat_prepare_entry(dat, req, 0);
-	if (ret < 0) {
-		WARN_ON(ret == -ENOENT);
+	if (ret < 0)
 		return ret;
-	}
 
 	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
 	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
 					     req->pr_entry_bh, kaddr);
+	start = le64_to_cpu(entry->de_start);
 	blocknr = le64_to_cpu(entry->de_blocknr);
 	kunmap_atomic(kaddr);
 
@@ -172,6 +181,15 @@ int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
 			return ret;
 		}
 	}
+	if (unlikely(start > nilfs_mdt_cno(dat))) {
+		nilfs_err(dat->i_sb,
+			  "vblocknr = %llu has abnormal lifetime: start cno (= %llu) > current cno (= %llu)",
+			  (unsigned long long)req->pr_entry_nr,
+			  (unsigned long long)start,
+			  (unsigned long long)nilfs_mdt_cno(dat));
+		nilfs_dat_abort_entry(dat, req);
+		return -EINVAL;
+	}
 
 	return 0;
 }