From: Zhihao Cheng <chengzhihao1@xxxxxxxxxx> [ Upstream commit 25fce616a61fc2f1821e4a9ce212d0e064707093 ] If target inode is a special file (eg. block/char device) with nlink count greater than 1, the inode with ui->data will be re-written on disk. However, UBIFS losts target inode's data_len while doing space budget. Bad space budget may let make_reservation() return with -ENOSPC, which could turn ubifs to read-only mode in do_writepage() process. Fetch a reproducer in [Link]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=216494 Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system") Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx> Signed-off-by: Richard Weinberger <richard@xxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/ubifs/dir.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 15b5664fd5c93..6039943877e10 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -1288,6 +1288,8 @@ static int do_rename(struct inode *old_dir, struct dentry *old_dentry, if (unlink) { ubifs_assert(c, inode_is_locked(new_inode)); + /* Budget for old inode's data when its nlink > 1. */ + req.dirtied_ino_d = ALIGN(ubifs_inode(new_inode)->data_len, 8); err = ubifs_purge_xattrs(new_inode); if (err) return err; -- 2.39.2