On Fri, Oct 13, 2023 at 05:40:57PM +0800, cheng.lin130@xxxxxxxxxx wrote: > > On Fri, Oct 13, 2023 at 03:27:30PM +0800, cheng.lin130@xxxxxxxxxx wrote: > > > From: Cheng Lin <cheng.lin130@xxxxxxxxxx> > > > > > > Avoid inode nlink overflow or underflow. > > > > > > Signed-off-by: Cheng Lin <cheng.lin130@xxxxxxxxxx> > > > --- > > I'm very confused. There's no explanation why that's needed. As it > > stands it's not possible to provide a useful review. > > I'm not saying it's wrong. I just don't understand why and even if this > > should please show up in the commit message. > In an xfs issue, there was an nlink underflow of a directory inode. There > is a key information in the kernel messages, that is the WARN_ON from > drop_nlink(). However, VFS did not prevent the underflow. I'm not sure > if this behavior is inadvertent or specifically designed. As an abnormal > situation, perhaps prohibiting nlink overflow or underflow is a better way > to handle it. > Request for your comment. I was trying to steer you towards modifying vfs_rmdir and vfs_unlink to check that i_nlink of the files involved aren't somehow already zero and returning -EFSCORRUPTED if they are. Not messing around with drop_nlink. --D
