Merge tag 'mm-hotfixes-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc hotfixes from Andrew Morton:
 "Five hotfixes - three for nilfs2, two for MM. For are cc:stable, one
  is not"

* tag 'mm-hotfixes-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  nilfs2: fix leak of nilfs_root in case of writer thread creation failure
  nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level()
  nilfs2: fix use-after-free bug of struct nilfs_root
  mm/damon/core: initialize damon_target->list in damon_new_target()
  mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page

2 files changed, 21 insertions, 5 deletions

diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 67f63cfeade5..232dd7b6cca1 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -328,6 +328,7 @@ struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
 	struct inode *inode;
 	struct nilfs_inode_info *ii;
 	struct nilfs_root *root;
+	struct buffer_head *bh;
 	int err = -ENOMEM;
 	ino_t ino;
 
@@ -343,11 +344,25 @@ struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
 	ii->i_state = BIT(NILFS_I_NEW);
 	ii->i_root = root;
 
-	err = nilfs_ifile_create_inode(root->ifile, &ino, &ii->i_bh);
+	err = nilfs_ifile_create_inode(root->ifile, &ino, &bh);
 	if (unlikely(err))
 		goto failed_ifile_create_inode;
 	/* reference count of i_bh inherits from nilfs_mdt_read_block() */
 
+	if (unlikely(ino < NILFS_USER_INO)) {
+		nilfs_warn(sb,
+			   "inode bitmap is inconsistent for reserved inodes");
+		do {
+			brelse(bh);
+			err = nilfs_ifile_create_inode(root->ifile, &ino, &bh);
+			if (unlikely(err))
+				goto failed_ifile_create_inode;
+		} while (ino < NILFS_USER_INO);
+
+		nilfs_info(sb, "repaired inode bitmap for reserved inodes");
+	}
+	ii->i_bh = bh;
+
 	atomic64_inc(&root->inodes_count);
 	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode->i_ino = ino;
@@ -440,6 +455,8 @@ int nilfs_read_inode_common(struct inode *inode,
 	inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 	inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
 	inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
+	if (nilfs_is_metadata_file_inode(inode) && !S_ISREG(inode->i_mode))
+		return -EIO; /* this inode is for metadata and corrupted */
 	if (inode->i_nlink == 0)
 		return -ESTALE; /* this inode is deleted */
 
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 6e4a7c4228c7..b4cebad21b48 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -2790,10 +2790,9 @@ int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root)
 	inode_attach_wb(nilfs->ns_bdev->bd_inode, NULL);
 
 	err = nilfs_segctor_start_thread(nilfs->ns_writer);
-	if (err) {
-		kfree(nilfs->ns_writer);
-		nilfs->ns_writer = NULL;
-	}
+	if (unlikely(err))
+		nilfs_detach_log_writer(sb);
+
 	return err;
 }