Re: [PATCH 2/3] xfs: disallow broken ioctls without compat-32-bit-time

From: Christoph Hellwig
Date: Tue Jan 07 2020 - 09:16:38 EST

On Thu, Jan 02, 2020 at 10:07:49AM -0800, Darrick J. Wong wrote:
> > Sorry I missed that comment earlier. I've had a fresh look now, but
> > I think we still need to deprecate XFS_IOC_SWAPEXT and add a
> > v5 version of it, since the comparison will fail as soon as the range
> > of the inode timestamps is extended beyond 2038, otherwise the
> > comparison will always be false, or require comparing the truncated
> > time values which would add yet another representation.
> I prefer we replace the old SWAPEXT with a new version to get rid of
> struct xfs_bstat. Though a SWAPEXT_V5 probably only needs to contain
> the *stat fields that swapext actually needs to check that the file
> hasn't been changed, which would be ino/gen/btime/ctime.
> (Maybe I'd add an offset/length too...)

And most importantly we need to lift it to the VFS instead of all the
crazy fs specific interfaces at the moment.