nilfs2-prevent-warning-in-nilfs_dat_commit_end.patch removed from -mm tree

The quilt patch titled
Subject: nilfs2: prevent WARNING in nilfs_dat_commit_end()
has been removed from the -mm tree. Its filename was
nilfs2-prevent-warning-in-nilfs_dat_commit_end.patch

This patch was dropped because it was merged into the mm-nonmm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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From: Ryusuke Konishi <[email protected]>
Subject: nilfs2: prevent WARNING in nilfs_dat_commit_end()
Date: Fri, 27 Jan 2023 22:22:02 +0900

If nilfs2 reads a corrupted disk image and its DAT metadata file contains invalid lifetime data for a virtual block number, a kernel warning can be generated by the WARN_ON check in nilfs_dat_commit_end() and can panic if the kernel is booted with panic_on_warn.

This patch avoids the issue with a sanity check that treats it as an error.

Since error return is not allowed in the execution phase of nilfs_dat_commit_end(), this inserts that sanity check in nilfs_dat_prepare_end(), which prepares for nilfs_dat_commit_end().

As the error code, -EINVAL is returned to notify bmap layer of the metadata corruption. When the bmap layer sees this code, it handles the abnormal situation and replaces the return code with -EIO as it should.

---

@@ -158,6 +158,7 @@ void nilfs_dat_commit_start(struct inode
 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;

@@ -169,6 +170,7 @@ int nilfs_dat_prepare_end(struct inode *
 	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);
 

@@ -179,6 +181,15 @@ int nilfs_dat_prepare_end(struct inode *
 			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;
 }

_

Patches currently in -mm which might be from [email protected] are